Merge origin/master into benvin/virtual-deb

A puppet remote drops the query string on `/v3/releases`, so `?module=<slug>` reaches the Forge unfiltered and clients get releases of every module instead of the one they asked for.

- forward validated `module`, `limit` (capped at 100) and `offset` on `v3/releases` via `QueryForwarder`
- document the forwarded params and the Forge API `base_url` in `docs/puppet/remote.md`

Reviewed-on: #161
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>

README.md

@@ -29,7 +29,7 @@ Each type's paths, Terraform examples and local/virtual behaviour are in `docs/<
 - `alpine`: [remote](docs/alpine/remote.md), [remote-github](docs/alpine/remote-github.md)
 - `ansible`: [remote](docs/ansible/remote.md), [local](docs/ansible/local.md), [virtual](docs/ansible/virtual.md)
 - `cargo`: [remote](docs/cargo/remote.md)
-- `deb`: [remote](docs/deb/remote.md), [remote-github](docs/deb/remote-github.md)
+- `deb`: [remote](docs/deb/remote.md), [remote-github](docs/deb/remote-github.md), [virtual](docs/deb/virtual.md)
 - `docker`: [remote](docs/docker/remote.md), [local](docs/docker/local.md)
 - `generic`: [remote](docs/generic/remote.md)
 - `gems`: [remote](docs/gems/remote.md), [local](docs/gems/local.md), [virtual](docs/gems/virtual.md)
@@ -37,7 +37,7 @@ Each type's paths, Terraform examples and local/virtual behaviour are in `docs/<
 - `helm`: [remote](docs/helm/remote.md), [local](docs/helm/local.md), [virtual](docs/helm/virtual.md)
 - `npm`: [remote](docs/npm/remote.md), [local](docs/npm/local.md), [virtual](docs/npm/virtual.md)
 - `nuget`: [remote](docs/nuget/remote.md)
-- `puppet`: [remote](docs/puppet/remote.md), [local](docs/puppet/local.md)
+- `puppet`: [remote](docs/puppet/remote.md), [local](docs/puppet/local.md), [virtual](docs/puppet/virtual.md)
 - `pypi`: [remote](docs/pypi/remote.md)
 - `rpm`: [remote](docs/rpm/remote.md), [remote-github](docs/rpm/remote-github.md)
 - `terraform`: [remote](docs/terraform/remote.md), [local](docs/terraform/local.md)

docs/deb/virtual.md

@@ -0,0 +1,32 @@
+# `deb` virtual
+
+A deb virtual serves one apt source over local and remote deb members at
+`/api/v1/virtual/<name>/`, in either the flat (`./`) or `dists/<suite>` layout.
+
+- Packages indexes are merged; on a duplicate (Package, Version, Architecture)
+  the earlier member wins.
+- The Release is generated unsigned with `Acquire-By-Hash: yes`; indexes are
+  served by name and by SHA256 from the current and previous merge.
+- `Filename` points at the virtual (`<member>/<path>`), which 302s to the
+  owning member.
+- All members must share one layout; mixing flat and suite members is
+  unsupported (suite requests fail with 502).
+- A member error fails the request with 502. Merges are cached for 60s per
+  suite, up to 32 suites per virtual.
+
+```hcl
+resource "artifactapi_virtual" "deb" {
+  name         = "deb"
+  package_type = "deb"
+  members      = [artifactapi_local_deb.internal.name, artifactapi_remote_github_deb.tool.name]
+}
+```
+
+```
+# /etc/apt/sources.list.d/artifactapi.list (flat)
+deb [trusted=yes] https://artifactapi.example.com/api/v1/virtual/deb/ ./
+# suite layout
+deb [trusted=yes] https://artifactapi.example.com/api/v1/virtual/debian/ trixie main
+```
+
+Upload to the local member directly; the virtual is read-only.

docs/puppet/remote.md

@@ -5,3 +5,6 @@ Shared classification, TTL and eviction rules: [caching](../common/caching.md).
 | Type | Mutable (auto-detected) | Immutable (auto-detected) |
 |---|---|---|
 | `puppet` | `v3/modules/*`, `v3/releases*` | `.tar.gz` |
+
+`/v3/releases` forwards the `module`, `limit` and `offset` query params
+upstream; set `base_url` to the Forge API root, e.g. `https://forgeapi.puppet.com`.

docs/puppet/virtual.md

@@ -0,0 +1,37 @@
+# `puppet` virtual
+
+A puppet virtual serves one Forge v3 API over local and remote puppet members:
+`puppet module install` and r10k work against `/api/v1/virtual/<name>`, with
+dependencies resolved across members.
+
+- `/v3/releases?module=<slug>` merges member releases; on a duplicate version
+  the earlier member wins. Releases are newest first, paginated with
+  `limit` (up to 100) and `offset`; pagination links and `file_uri` are
+  relative to the Forge root, so downloads route via the virtual.
+- `/v3/modules/<slug>` lists the merged releases with the highest version as
+  `current_release`.
+- `/v3/releases/<slug>-<version>` and `/v3/files/<file>` 302 to the member
+  owning that release.
+- A member error fails the request with 502; a member without the module is
+  skipped. Merges, and modules no member has, are cached for 60s.
+
+```hcl
+resource "artifactapi_virtual" "puppet" {
+  name         = "puppet"
+  package_type = "puppet"
+  members      = [artifactapi_local_puppet.internal.name, artifactapi_remote_puppet.forge.name]
+}
+```
+
+```bash
+puppet module install unkin-hello \
+  --module_repository https://artifactapi.example.com/api/v1/virtual/puppet
+```
+
+```yaml
+# r10k.yaml
+forge:
+  baseurl: https://artifactapi.example.com/api/v1/virtual/puppet
+```
+
+Upload to the local member directly; the virtual is read-only.

e2e-docker/README.md

@@ -40,7 +40,9 @@ already-running stack.
   downloads 302 to the owning member); ansible over two locals via stock
   `ansible-galaxy` (install through the virtual, download 302 to the owner);
   goproxy over two locals via a stock `golang:1.25` client (merged versions,
-  member order wins, version files 302 to the owning member).
+  member order wins, version files 302 to the owning member); puppet over two
+  locals via real `puppet module install` (dependency resolved across members)
+  and `r10k`, downloads 302 to the owning member.
 - **Mirrorlist** — an rpm remote with a `mirrorlist` of extra upstream mirrors
   (pool = `base_url` + `mirrorlist`): round-robin distribution across both mirrors
   (constant-body `mockupstreama` / `mockupstreamb`), failover past a dead primary,

e2e-docker/deb_virtual_test.go

@@ -0,0 +1,115 @@
+//go:build dockere2e
+
+package e2edocker
+
+import (
+	"net/http"
+	"os"
+	"os/exec"
+	"strings"
+	"testing"
+	"time"
+
+	"git.unkin.net/unkin/artifactapi/internal/testsupport"
+)
+
+// TestVirtualDebMerge merges two local deb repos carrying the same package: the
+// first member wins the duplicate, and a real apt sees both members' packages
+// and installs through the virtual.
+func TestVirtualDebMerge(t *testing.T) {
+	createRepo(t, `{"name":"vdeb-a","package_type":"deb","repo_type":"local"}`)
+	createRepo(t, `{"name":"vdeb-b","package_type":"deb","repo_type":"local"}`)
+	defer deleteRepo(t, "vdeb-a")
+	defer deleteRepo(t, "vdeb-b")
+
+	uploadFile(t, "vdeb-a", "vdeb-one_1.0.0_amd64.deb", testsupport.MinimalDeb("vdeb-one", "1.0.0", "amd64"), "application/vnd.debian.binary-package")
+	uploadFile(t, "vdeb-b", "vdeb-one_1.0.0_amd64.deb", testsupport.MinimalDeb("vdeb-one", "1.0.0", "amd64"), "application/vnd.debian.binary-package")
+	uploadFile(t, "vdeb-b", "vdeb-two_2.0.0_amd64.deb", testsupport.MinimalDeb("vdeb-two", "2.0.0", "amd64"), "application/vnd.debian.binary-package")
+
+	// Local indexes regenerate asynchronously; merge only once vdeb-b lists both.
+	deadline := time.Now().Add(15 * time.Second)
+	for {
+		resp, body := doRequest(t, http.MethodGet, api("/api/v1/local/vdeb-b/Packages"), nil, "")
+		if resp.StatusCode == http.StatusOK && strings.Contains(string(body), "vdeb-two") || time.Now().After(deadline) {
+			break
+		}
+		time.Sleep(500 * time.Millisecond)
+	}
+
+	createVirtual(t, `{"name":"vdeb","package_type":"deb","members":["vdeb-a","vdeb-b"]}`)
+	defer deleteVirtual(t, "vdeb")
+
+	_, body := doRequest(t, http.MethodGet, api("/api/v1/virtual/vdeb/Packages"), nil, "")
+	pk := string(body)
+	if strings.Count(pk, "Package: vdeb-one\n") != 1 || !strings.Contains(pk, "Filename: vdeb-a/pool/vdeb-one_1.0.0_amd64.deb") ||
+		!strings.Contains(pk, "Filename: vdeb-b/pool/vdeb-two_2.0.0_amd64.deb") {
+		t.Fatalf("merged Packages should hold vdeb-one from the first member and vdeb-two:\n%s", pk)
+	}
+
+	network := os.Getenv("COMPOSE_NETWORK")
+	internal := os.Getenv("ARTIFACTAPI_INTERNAL")
+	if network == "" || internal == "" {
+		t.Skip("COMPOSE_NETWORK/ARTIFACTAPI_INTERNAL not set; skipping real apt")
+	}
+	if _, err := exec.LookPath("docker"); err != nil {
+		t.Skip("docker not available on the test host")
+	}
+	script := "set -euo pipefail; " +
+		"rm -f /etc/apt/sources.list.d/*; " +
+		"echo \"deb [trusted=yes] $URL ./\" > /etc/apt/sources.list.d/vdeb.list; " +
+		"apt-get update; " +
+		"apt-cache policy vdeb-one vdeb-two | tee /dev/stderr | grep -c virtual/vdeb | grep -qx 2; " +
+		"apt-get install -y vdeb-one vdeb-two; " +
+		"dpkg -s vdeb-one vdeb-two"
+	out, err := exec.Command("docker", "run", "--rm", "--network", network,
+		"-e", "URL="+strings.TrimRight(internal, "/")+"/api/v1/virtual/vdeb/",
+		"debian:13", "bash", "-c", script).CombinedOutput()
+	if err != nil {
+		t.Fatalf("real apt against deb virtual failed: %v\n%s", err, out)
+	}
+}
+
+// TestVirtualDebSuite merges two proxied deb.debian.org remotes and drives a
+// real apt through the virtual's dists/<suite> layout (by-hash indexes).
+func TestVirtualDebSuite(t *testing.T) {
+	network := os.Getenv("COMPOSE_NETWORK")
+	internal := os.Getenv("ARTIFACTAPI_INTERNAL")
+	if network == "" || internal == "" {
+		t.Skip("COMPOSE_NETWORK/ARTIFACTAPI_INTERNAL not set; skipping real apt")
+	}
+	if _, err := exec.LookPath("docker"); err != nil {
+		t.Skip("docker not available on the test host")
+	}
+	for _, n := range []string{"vdebs-a", "vdebs-b"} {
+		createRepo(t, `{"name":"`+n+`","package_type":"deb","repo_type":"remote","base_url":"http://deb.debian.org/debian"}`)
+		defer deleteRepo(t, n)
+	}
+	createVirtual(t, `{"name":"vdebs","package_type":"deb","members":["vdebs-a","vdebs-b"]}`)
+	defer deleteVirtual(t, "vdebs")
+
+	resp, rel := doRequest(t, http.MethodGet, api("/api/v1/virtual/vdebs/dists/trixie-updates/Release"), nil, "")
+	if resp.StatusCode != http.StatusOK || !strings.Contains(string(rel), "Acquire-By-Hash: yes\n") ||
+		!strings.Contains(string(rel), " main/binary-amd64/Packages.gz\n") {
+		t.Fatalf("merged suite Release: status %d:\n%s", resp.StatusCode, rel)
+	}
+
+	script := "set -euo pipefail; " +
+		"rm -f /etc/apt/sources.list.d/*; " +
+		"echo \"deb [trusted=yes] $URL trixie-updates main\" > /etc/apt/sources.list.d/vdebs.list; " +
+		"apt-get update; " +
+		"idx=/tmp/avail; apt-cache dumpavail > $idx; " +
+		"grep -q '^Filename: vdebs-a/pool/' $idx; if grep -q '^Filename: vdebs-b/' $idx; then echo 'vdebs-b not deduped'; exit 1; fi; " +
+		"pkg=$(awk '/^Package:/{p=$2} /^Size:/{if(!m||$2<m){m=$2;b=p}} END{print b}' $idx); " +
+		"cd /tmp && apt-get download $pkg && ls -l /tmp/*.deb"
+	out, err := exec.Command("docker", "run", "--rm", "--network", network,
+		"-e", "URL="+strings.TrimRight(internal, "/")+"/api/v1/virtual/vdebs/",
+		"debian:13", "bash", "-c", script).CombinedOutput()
+	if err != nil {
+		t.Fatalf("real apt against deb virtual suite failed: %v\n%s", err, out)
+	}
+	t.Logf("%s", out)
+	resp, _ = doRequest(t, http.MethodGet, api("/api/v1/remote/vdebs-a/dists/trixie-updates/main/binary-amd64/Packages.xz"), nil, "")
+	if src := resp.Header.Get("X-Artifact-Source"); resp.StatusCode != http.StatusOK || src != "cache" {
+		t.Fatalf("member index the virtual merged should be cached: status %d source %q", resp.StatusCode, src)
+	}
+}

e2e-docker/puppet_local_test.go

@@ -17,13 +17,18 @@ import (
 const puppetHelloMetadata = `{"name":"unkin-hello","version":"0.1.0","author":"unkin","summary":"e2e","license":"Apache-2.0","source":"https://example.invalid","dependencies":[{"name":"puppetlabs/stdlib","version_requirement":">= 4.0.0 < 10.0.0"}]}`
 
 func puppetModuleTarball(t *testing.T) []byte {
+	t.Helper()
+	return puppetTarball(t, "unkin-hello-0.1.0", puppetHelloMetadata)
+}
+
+func puppetTarball(t *testing.T, dir, metadata string) []byte {
 	t.Helper()
 	var buf bytes.Buffer
 	zw := gzip.NewWriter(&buf)
 	tw := tar.NewWriter(zw)
 	for name, body := range map[string]string{
-		"unkin-hello-0.1.0/metadata.json":     puppetHelloMetadata,
+		dir + "/metadata.json":     metadata,
-		"unkin-hello-0.1.0/manifests/init.pp": "class hello {}\n",
+		dir + "/manifests/init.pp": "class stub {}\n",
 	} {
 		if err := tw.WriteHeader(&tar.Header{Name: name, Mode: 0o644, Size: int64(len(body)), ModTime: time.Now()}); err != nil {
 			t.Fatal(err)

e2e-docker/puppet_virtual_test.go

@@ -0,0 +1,83 @@
+//go:build dockere2e
+
+package e2edocker
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"os/exec"
+	"strings"
+	"testing"
+	"time"
+)
+
+// TestVirtualPuppetInstall puts unkin-hello and its stdlib dependency on two
+// puppet locals and installs through a virtual over both with the real puppet
+// module tool (dependencies resolved) and r10k, downloads 302ing to each owner.
+func TestVirtualPuppetInstall(t *testing.T) {
+	network := os.Getenv("COMPOSE_NETWORK")
+	internal := strings.TrimRight(os.Getenv("ARTIFACTAPI_INTERNAL"), "/")
+	if network == "" || internal == "" {
+		t.Skip("COMPOSE_NETWORK/ARTIFACTAPI_INTERNAL not set; run via scripts/docker-e2e.sh")
+	}
+	if _, err := exec.LookPath("docker"); err != nil {
+		t.Skip("docker not available on the test host")
+	}
+
+	id := time.Now().UnixNano()
+	a, b, virt := fmt.Sprintf("e2e-puppet-a-%d", id), fmt.Sprintf("e2e-puppet-b-%d", id), fmt.Sprintf("e2e-puppet-v-%d", id)
+	modules := map[string]struct{ file, dir, meta string }{
+		a: {"unkin-hello-0.1.0.tar.gz", "unkin-hello-0.1.0", puppetHelloMetadata},
+		b: {"puppetlabs-stdlib-9.6.0.tar.gz", "puppetlabs-stdlib-9.6.0", `{"name":"puppetlabs-stdlib","version":"9.6.0","author":"puppetlabs","summary":"stub","license":"Apache-2.0","source":"https://example.invalid","dependencies":[]}`},
+	}
+	for repo, m := range modules {
+		createRepo(t, fmt.Sprintf(`{"name":%q,"package_type":"puppet","repo_type":"local"}`, repo))
+		defer deleteRepo(t, repo)
+		if resp, body := doRequest(t, http.MethodPut, api("/api/v2/remotes/"+repo+"/files/"+m.file), puppetTarball(t, m.dir, m.meta), "application/gzip"); resp.StatusCode != http.StatusCreated {
+			t.Fatalf("upload %s: %d %s", m.file, resp.StatusCode, body)
+		}
+		defer doRequest(t, http.MethodDelete, api("/api/v2/remotes/"+repo+"/files/v3/files/"+m.file), nil, "")
+		if resp, body := getEventually(t, api("/api/v1/local/"+repo+"/v3/releases/"+strings.TrimSuffix(m.file, ".tar.gz")), 15*time.Second); resp.StatusCode != http.StatusOK {
+			t.Fatalf("%s never indexed: %d %s", m.file, resp.StatusCode, body)
+		}
+	}
+	createVirtual(t, fmt.Sprintf(`{"name":%q,"package_type":"puppet","members":[%q,%q]}`, virt, a, b))
+	defer deleteVirtual(t, virt)
+
+	forge := internal + "/api/v1/virtual/" + virt
+	run := func(image, script string) string {
+		t.Helper()
+		out, err := exec.Command("docker", "run", "--rm", "--network", network, "--entrypoint", "sh", image, "-c", "set -eu; "+script).CombinedOutput()
+		if err != nil {
+			t.Fatalf("%s failed: %v\n%s", image, err, out)
+		}
+		return string(out)
+	}
+
+	out := run("ghcr.io/openvoxproject/openvoxagent:latest", "export PATH=/opt/puppetlabs/bin:$PATH; puppet module install unkin-hello --module_repository "+forge+" --target-dir /tmp/mods && puppet module list --color=false --modulepath /tmp/mods")
+	for _, want := range []string{"unkin-hello (v0.1.0)", "puppetlabs-stdlib (v9.6.0)"} {
+		if !strings.Contains(out, want) {
+			t.Fatalf("puppet module install missing %q:\n%s", want, out)
+		}
+	}
+
+	out = run("ghcr.io/voxpupuli/r10k:latest", "cd /tmp && printf 'forge:\\n  baseurl: "+forge+"\\n' > r10k.yaml && "+
+		"printf \"mod 'unkin-hello', '0.1.0'\\nmod 'puppetlabs-stdlib', '9.6.0'\\n\" > Puppetfile && "+
+		"r10k puppetfile install -c r10k.yaml && cat modules/hello/metadata.json modules/stdlib/metadata.json")
+	if !strings.Contains(out, `"unkin-hello"`) || !strings.Contains(out, `"puppetlabs-stdlib"`) {
+		t.Fatalf("r10k did not install both modules:\n%s", out)
+	}
+
+	noRedirect := &http.Client{CheckRedirect: func(*http.Request, []*http.Request) error { return http.ErrUseLastResponse }}
+	for repo, m := range modules {
+		resp, err := noRedirect.Get(api("/api/v1/virtual/" + virt + "/v3/files/" + m.file))
+		if err != nil {
+			t.Fatal(err)
+		}
+		_ = resp.Body.Close()
+		if loc := resp.Header.Get("Location"); resp.StatusCode != http.StatusFound || !strings.HasSuffix(loc, "/api/v1/local/"+repo+"/v3/files/"+m.file) {
+			t.Errorf("%s = %d %q, want 302 to %s", m.file, resp.StatusCode, loc, repo)
+		}
+	}
+}

internal/api/v1/proxy.go

@@ -215,6 +215,10 @@ func (h *ProxyHandler) handleVirtual(w http.ResponseWriter, r *http.Request) {
 		h.serveVirtualAnsible(w, r, *virt, path, proxyBaseURL)
 		return
 	}
+	if virt.PackageType == models.PackagePuppet {
+		h.serveVirtualPuppet(w, r, *virt, path, proxyBaseURL)
+		return
+	}
 	if virt.PackageType == models.PackageGoProxy {
 		h.serveVirtualGoProxy(w, r, *virt, path)
 		return

internal/api/v1/puppet_virtual.go

@@ -0,0 +1,77 @@
+package v1
+
+import (
+	"encoding/json"
+	"errors"
+	"log/slog"
+	"net/http"
+	"strings"
+
+	"git.unkin.net/unkin/artifactapi/internal/provider/puppet"
+	"git.unkin.net/unkin/artifactapi/internal/virtual"
+	"git.unkin.net/unkin/artifactapi/pkg/models"
+)
+
+// serveVirtualPuppet serves the merged Forge v3 module and release listings
+// and 302s release details and downloads to the member owning that release.
+func (h *ProxyHandler) serveVirtualPuppet(w http.ResponseWriter, r *http.Request, virt models.Virtual, path, proxyBaseURL string) {
+	var doc any
+	var err error
+	switch {
+	case path == "v3/releases":
+		q := r.URL.Query()
+		slug := puppet.NormalizeSlug(q.Get("module"))
+		if !puppet.ValidSlug(slug) {
+			forgeError(w, http.StatusBadRequest, "module is required")
+			return
+		}
+		var d *virtual.PuppetDoc
+		d, err = h.virtualEngine.PuppetReleases(r.Context(), virt, slug)
+		releases := []any{}
+		if errors.Is(err, virtual.ErrNotFound) {
+			err = nil
+		} else if err == nil {
+			for _, rel := range d.Releases {
+				releases = append(releases, rel)
+			}
+		}
+		doc = puppet.ReleasesPage(slug, releases, q)
+	case strings.HasPrefix(path, "v3/modules/"):
+		slug := puppet.NormalizeSlug(strings.TrimPrefix(path, "v3/modules/"))
+		if !puppet.ValidSlug(slug) {
+			puppet.NotFound(w)
+			return
+		}
+		var d *virtual.PuppetDoc
+		if d, err = h.virtualEngine.PuppetReleases(r.Context(), virt, slug); err == nil {
+			doc, err = virtual.PuppetModule(d)
+		}
+	default:
+		var loc string
+		loc, err = h.virtualEngine.PuppetRedirect(r.Context(), virt, path, proxyBaseURL)
+		if err == nil {
+			w.Header().Set("Cache-Control", "no-store")
+			w.Header().Set("Vary", "Host, X-Forwarded-Proto")
+			http.Redirect(w, r, loc, http.StatusFound)
+			return
+		}
+	}
+	switch {
+	case errors.Is(err, virtual.ErrNotFound):
+		puppet.NotFound(w)
+	case errors.Is(err, virtual.ErrBadPath):
+		forgeError(w, http.StatusBadRequest, err.Error())
+	case err != nil:
+		slog.Error("virtual puppet fetch failed", "virtual", virt.Name, "path", path, "error", err)
+		forgeError(w, http.StatusBadGateway, "bad gateway")
+	default:
+		w.Header().Set("X-Artifact-Source", "virtual")
+		puppet.WriteJSON(w, doc)
+	}
+}
+
+func forgeError(w http.ResponseWriter, code int, msg string) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(code)
+	_ = json.NewEncoder(w).Encode(map[string]any{"message": http.StatusText(code), "errors": []string{msg}})
+}

internal/api/v1/puppet_virtual_test.go

@@ -0,0 +1,90 @@
+package v1
+
+import (
+	"context"
+	"net/http"
+	"strings"
+	"testing"
+
+	"git.unkin.net/unkin/artifactapi/internal/provider"
+	"git.unkin.net/unkin/artifactapi/internal/virtual"
+	"git.unkin.net/unkin/artifactapi/pkg/models"
+)
+
+func TestPuppetVirtualOverLocals(t *testing.T) {
+	h, srv := npmTestServer(t)
+	h.virtualEngine = virtual.NewEngine(h.db, nil)
+	a, b := npmRepo(t, h, models.PackagePuppet), npmRepo(t, h, models.PackagePuppet)
+	for _, p := range []struct{ repo, version string }{{a, "0.1.0"}, {b, "0.1.0"}, {b, "0.2.0"}} {
+		file := "v3/files/unkin-hello-" + p.version + ".tar.gz"
+		meta := &provider.PuppetMetadata{RepoName: p.repo, FilePath: file, ContentHash: "sha256:00", Slug: "unkin-hello", Version: p.version, MetadataJSON: `{"name":"unkin-hello","version":"` + p.version + `"}`}
+		if err := h.db.InsertPuppetMetadata(context.Background(), meta); err != nil {
+			t.Fatal(err)
+		}
+	}
+	virt := "v" + a
+	if err := h.db.CreateVirtual(context.Background(), &models.Virtual{Name: virt, PackageType: models.PackagePuppet, Members: []string{a, b}}); err != nil {
+		t.Fatal(err)
+	}
+	base := srv.URL + "/api/v1/virtual/" + virt
+
+	var page struct {
+		Pagination struct {
+			Total int
+			Next  *string
+		}
+		Results []struct {
+			Version string
+			FileURI string `json:"file_uri"`
+		}
+	}
+	getJSON(t, base+"/v3/releases?module=unkin/hello&limit=1", &page)
+	if page.Pagination.Total != 2 || len(page.Results) != 1 || page.Results[0].Version != "0.2.0" || page.Pagination.Next == nil {
+		t.Fatalf("page 1 = %+v", page)
+	}
+	if *page.Pagination.Next != "/v3/releases?limit=1&module=unkin-hello&offset=1" || page.Results[0].FileURI != "/v3/files/unkin-hello-0.2.0.tar.gz" {
+		t.Fatalf("links not relative to the forge root: next %q file_uri %q", *page.Pagination.Next, page.Results[0].FileURI)
+	}
+	getJSON(t, base+*page.Pagination.Next, &page)
+	if len(page.Results) != 1 || page.Results[0].Version != "0.1.0" || page.Pagination.Next != nil {
+		t.Fatalf("page 2 = %+v", page)
+	}
+
+	var mod struct {
+		CurrentRelease struct{ Version string } `json:"current_release"`
+		Releases       []struct{ Version string }
+	}
+	getJSON(t, base+"/v3/modules/unkin-hello", &mod)
+	if mod.CurrentRelease.Version != "0.2.0" || len(mod.Releases) != 2 {
+		t.Fatalf("module = %+v", mod)
+	}
+
+	noRedirect := &http.Client{CheckRedirect: func(*http.Request, []*http.Request) error { return http.ErrUseLastResponse }}
+	for p, want := range map[string]string{
+		"/v3/files/unkin-hello-0.1.0.tar.gz": "/api/v1/local/" + a + "/v3/files/unkin-hello-0.1.0.tar.gz",
+		"/v3/releases/unkin-hello-0.2.0":     "/api/v1/local/" + b + "/v3/releases/unkin-hello-0.2.0",
+	} {
+		resp, err := noRedirect.Get(base + p)
+		if err != nil {
+			t.Fatal(err)
+		}
+		_ = resp.Body.Close()
+		if resp.StatusCode != http.StatusFound || resp.Header.Get("Location") != srv.URL+want || resp.Header.Get("Cache-Control") != "no-store" {
+			t.Errorf("%s = %d %q %q, want 302 to %s", p, resp.StatusCode, resp.Header.Get("Location"), resp.Header.Get("Cache-Control"), want)
+		}
+	}
+
+	getJSON(t, base+"/v3/releases?module=unkin-absent", &page)
+	if page.Pagination.Total != 0 || len(page.Results) != 0 {
+		t.Fatalf("absent module = %+v", page)
+	}
+	for p, want := range map[string]int{
+		"/v3/releases":                       http.StatusBadRequest,
+		"/v3/modules/unkin-absent":           http.StatusNotFound,
+		"/v3/files/unkin-hello-0.9.0.tar.gz": http.StatusNotFound,
+	} {
+		if code, body := npmDo(t, http.MethodGet, base+p, ""); code != want || !strings.Contains(body, `"errors"`) {
+			t.Errorf("%s = %d %s, want %d", p, code, body, want)
+		}
+	}
+}

internal/provider/puppet/local.go

@@ -29,7 +29,7 @@ const filesPrefix = "v3/files/"
 // tarball basename that `puppet module build` produces.
 var releaseRe = regexp.MustCompile(`^([a-z0-9]+)-([a-z][a-z0-9_]*)-(\d+\.\d+\.\d+(?:-[0-9a-z.-]+)?(?:\+[0-9a-z.-]+)?)$`)
 
-func parseRelease(s string) (slug, version string, ok bool) {
+func ParseRelease(s string) (slug, version string, ok bool) {
 	m := releaseRe.FindStringSubmatch(strings.ToLower(s))
 	if m == nil {
 		return "", "", false
@@ -37,7 +37,12 @@ func parseRelease(s string) (slug, version string, ok bool) {
 	return m[1] + "-" + m[2], m[3], true
 }
 
-func normalizeSlug(s string) string {
+var slugRe = regexp.MustCompile(`^[a-z0-9]+-[a-z][a-z0-9_]*$`)
+
+// ValidSlug reports whether s is a normalized <owner>-<name> module slug.
+func ValidSlug(s string) bool { return slugRe.MatchString(s) }
+
+func NormalizeSlug(s string) string {
 	return strings.ToLower(strings.ReplaceAll(s, "/", "-"))
 }
 
@@ -45,7 +50,7 @@ func normalizeSlug(s string) string {
 // resolve straight to the stored file.
 func (p *Provider) ValidateUpload(filePath string) (storagePath, contentType string, err error) {
 	filename := strings.ToLower(path.Base(path.Clean("/" + filePath)))
-	if _, _, ok := parseRelease(strings.TrimSuffix(filename, ".tar.gz")); !ok || !strings.HasSuffix(filename, ".tar.gz") {
+	if _, _, ok := ParseRelease(strings.TrimSuffix(filename, ".tar.gz")); !ok || !strings.HasSuffix(filename, ".tar.gz") {
 		return "", "", fmt.Errorf("file must be named <owner>-<module>-<version>.tar.gz")
 	}
 	return filesPrefix + filename, "application/gzip", nil
@@ -82,7 +87,7 @@ func (p *Provider) AfterUpload(ctx context.Context, repoName, storagePath, conte
 		slog.Error("puppet metadata: read failed", "repo", repoName, "path", storagePath, "error", err)
 		return
 	}
-	slug, version, _ := parseRelease(strings.TrimSuffix(path.Base(storagePath), ".tar.gz"))
+	slug, version, _ := ParseRelease(strings.TrimSuffix(path.Base(storagePath), ".tar.gz"))
 	if meta.Slug != slug || meta.Version != version {
 		slog.Error("puppet metadata: metadata.json does not match filename", "repo", repoName, "path", storagePath, "name", meta.Slug, "version", meta.Version)
 		return
@@ -158,7 +163,7 @@ func parseModule(r io.Reader) (*provider.PuppetMetadata, error) {
 		if md.Name == "" || md.Version == "" {
 			return nil, errors.New("metadata.json missing name or version")
 		}
-		return &provider.PuppetMetadata{Slug: normalizeSlug(md.Name), Version: md.Version, MetadataJSON: string(body)}, nil
+		return &provider.PuppetMetadata{Slug: NormalizeSlug(md.Name), Version: md.Version, MetadataJSON: string(body)}, nil
 	}
 }
 
@@ -181,9 +186,9 @@ func (p *Provider) ServeLocalIndex(w http.ResponseWriter, r *http.Request, files
 	case clean == "v3/releases":
 		serveReleaseList(w, r, list)
 	case strings.HasPrefix(clean, "v3/releases/"):
-		slug, version, ok := parseRelease(strings.TrimPrefix(clean, "v3/releases/"))
+		slug, version, ok := ParseRelease(strings.TrimPrefix(clean, "v3/releases/"))
 		if !ok {
-			notFound(w)
+			NotFound(w)
 			return true
 		}
 		metas, err := list(slug)
@@ -193,23 +198,23 @@ func (p *Provider) ServeLocalIndex(w http.ResponseWriter, r *http.Request, files
 		}
 		for _, m := range metas {
 			if m.Version == version {
-				writeJSON(w, releaseObject(m))
+				WriteJSON(w, releaseObject(m))
 				return true
 			}
 		}
-		notFound(w)
+		NotFound(w)
 	case strings.HasPrefix(clean, "v3/modules/"):
-		slug := normalizeSlug(strings.TrimPrefix(clean, "v3/modules/"))
+		slug := NormalizeSlug(strings.TrimPrefix(clean, "v3/modules/"))
 		metas, err := list(slug)
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return true
 		}
 		if len(metas) == 0 {
-			notFound(w)
+			NotFound(w)
 			return true
 		}
-		writeJSON(w, moduleObject(metas))
+		WriteJSON(w, moduleObject(metas))
 	default:
 		return false
 	}
@@ -222,7 +227,22 @@ func (p *Provider) GenerateLocalIndex(ctx context.Context, files provider.FileSt
 
 func serveReleaseList(w http.ResponseWriter, r *http.Request, list func(string) ([]provider.PuppetMetadata, error)) {
 	q := r.URL.Query()
-	slug := normalizeSlug(q.Get("module"))
+	slug := NormalizeSlug(q.Get("module"))
+	metas, err := list(slug)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	releases := make([]any, len(metas))
+	for i, m := range metas {
+		releases[i] = releaseObject(m)
+	}
+	WriteJSON(w, ReleasesPage(slug, releases, q))
+}
+
+// ReleasesPage is one limit/offset page of a /v3/releases listing, with
+// pagination links relative to the Forge root.
+func ReleasesPage(slug string, releases []any, q url.Values) map[string]any {
 	limit, err := strconv.Atoi(q.Get("limit"))
 	if err != nil || limit <= 0 {
 		limit = 20
@@ -232,20 +252,10 @@ func serveReleaseList(w http.ResponseWriter, r *http.Request, list func(string)
 	if err != nil || offset < 0 {
 		offset = 0
 	}
-
+	offset = min(offset, len(releases))
-	metas, err := list(slug)
-	if err != nil {
-		http.Error(w, err.Error(), http.StatusInternalServerError)
-		return
-	}
-	offset = min(offset, len(metas))
-	results := []map[string]any{}
-	for _, m := range metas[offset : offset+min(limit, len(metas)-offset)] {
-		results = append(results, releaseObject(m))
-	}
 
 	page := func(off int) any {
-		if off < 0 || off >= len(metas) && off != 0 {
+		if off < 0 || off >= len(releases) && off != 0 {
 			return nil
 		}
 		v := url.Values{"limit": {strconv.Itoa(limit)}, "offset": {strconv.Itoa(off)}}
@@ -258,7 +268,7 @@ func serveReleaseList(w http.ResponseWriter, r *http.Request, list func(string)
 	if offset > 0 {
 		previous = page(max(offset-limit, 0))
 	}
-	writeJSON(w, map[string]any{
+	return map[string]any{
 		"pagination": map[string]any{
 			"limit":    limit,
 			"offset":   offset,
@@ -266,10 +276,10 @@ func serveReleaseList(w http.ResponseWriter, r *http.Request, list func(string)
 			"previous": previous,
 			"current":  page(offset),
 			"next":     page(offset + limit),
-			"total":    len(metas),
+			"total":    len(releases),
 		},
-		"results": results,
+		"results": releases[offset : offset+min(limit, len(releases)-offset)],
-	})
+	}
 }
 
 func owner(slug string) map[string]any {
@@ -329,7 +339,7 @@ func moduleObject(metas []provider.PuppetMetadata) map[string]any {
 	return obj
 }
 
-func writeJSON(w http.ResponseWriter, v any) {
+func WriteJSON(w http.ResponseWriter, v any) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
 	enc := json.NewEncoder(w)
@@ -337,7 +347,7 @@ func writeJSON(w http.ResponseWriter, v any) {
 	_ = enc.Encode(v)
 }
 
-func notFound(w http.ResponseWriter) {
+func NotFound(w http.ResponseWriter) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusNotFound)
 	_, _ = io.WriteString(w, `{"message":"404 Not Found","errors":["The requested resource could not be found"]}`)
@@ -349,11 +359,11 @@ func sortReleases(metas []provider.PuppetMetadata) {
 		if c := strings.Compare(a.Slug, b.Slug); c != 0 {
 			return c
 		}
-		return compareSemver(b.Version, a.Version)
+		return CompareSemver(b.Version, a.Version)
 	})
 }
 
-func compareSemver(a, b string) int {
+func CompareSemver(a, b string) int {
 	a, _, _ = strings.Cut(a, "+")
 	b, _, _ = strings.Cut(b, "+")
 	aCore, aPre, aHasPre := strings.Cut(a, "-")

internal/provider/puppet/local_test.go

@@ -291,11 +291,11 @@ func TestFilesFallThrough(t *testing.T) {
 func TestCompareSemver(t *testing.T) {
 	ordered := []string{"0.1.0", "0.2.0", "0.10.0", "1.0.0-alpha", "1.0.0-alpha.1", "1.0.0-beta", "1.0.0-beta.2", "1.0.0-beta.11", "1.0.0", "1.0.1+build"}
 	for i := 1; i < len(ordered); i++ {
-		if compareSemver(ordered[i-1], ordered[i]) >= 0 || compareSemver(ordered[i], ordered[i-1]) <= 0 {
+		if CompareSemver(ordered[i-1], ordered[i]) >= 0 || CompareSemver(ordered[i], ordered[i-1]) <= 0 {
 			t.Errorf("%s should sort before %s", ordered[i-1], ordered[i])
 		}
 	}
-	if compareSemver("1.0.0+a", "1.0.0+b") != 0 {
+	if CompareSemver("1.0.0+a", "1.0.0+b") != 0 {
 		t.Error("build metadata must not affect precedence")
 	}
 }

internal/provider/puppet/puppet.go

@@ -3,6 +3,7 @@ package puppet
 import (
 	"context"
 	"net/http"
+	"strconv"
 	"strings"
 
 	"git.unkin.net/unkin/artifactapi/internal/auth"
@@ -39,6 +40,32 @@ func (p *Provider) UpstreamURL(remote models.Remote, path string) string {
 	return strings.TrimRight(remote.BaseURL, "/") + "/" + strings.TrimLeft(path, "/")
 }
 
+// ForwardedQuery keeps the module filter and pagination on release listings.
+func (p *Provider) ForwardedQuery(path string) map[string]provider.QueryValidator {
+	if path != "v3/releases" {
+		return nil
+	}
+	return map[string]provider.QueryValidator{"module": moduleParam, "limit": pageLimit, "offset": pageOffset}
+}
+
+func moduleParam(v string) (string, bool) {
+	v = NormalizeSlug(v)
+	return v, ValidSlug(v)
+}
+
+func pageLimit(v string) (string, bool) {
+	n, err := strconv.ParseUint(v, 10, 32)
+	if err != nil || n == 0 {
+		return "", false
+	}
+	return strconv.FormatUint(min(n, 100), 10), true
+}
+
+func pageOffset(v string) (string, bool) {
+	n, err := strconv.ParseUint(v, 10, 32)
+	return strconv.FormatUint(n, 10), err == nil
+}
+
 func (p *Provider) RewritesResponse() {}
 
 func (p *Provider) RewriteResponse(body []byte, remote models.Remote, proxyBaseURL string) ([]byte, error) {

internal/provider/puppet/puppet_test.go

@@ -76,3 +76,28 @@ func TestAuthHeaders(t *testing.T) {
 		t.Error("no credentials, no header")
 	}
 }
+
+func TestForwardedQuery(t *testing.T) {
+	p := &Provider{}
+	if p.ForwardedQuery("v3/files/a-b-1.0.0.tar.gz") != nil || p.ForwardedQuery("v3/modules/a-b") != nil {
+		t.Fatal("only release listings forward a query")
+	}
+	f := p.ForwardedQuery("v3/releases")
+	for name, c := range map[string]struct {
+		in, want string
+		ok       bool
+	}{
+		"module": {"Puppetlabs/stdlib", "puppetlabs-stdlib", true},
+		"limit":  {"500", "100", true},
+		"offset": {"40", "40", true},
+	} {
+		if got, ok := f[name](c.in); got != c.want || ok != c.ok {
+			t.Errorf("%s(%q) = %q %v, want %q %v", name, c.in, got, ok, c.want, c.ok)
+		}
+	}
+	for name, bad := range map[string]string{"module": "../x", "limit": "0", "offset": "-1"} {
+		if _, ok := f[name](bad); ok {
+			t.Errorf("%s(%q) accepted", name, bad)
+		}
+	}
+}

internal/virtual/deb_merger.go

@@ -0,0 +1,245 @@
+package virtual
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/hex"
+	"fmt"
+	"path"
+	"regexp"
+	"slices"
+	"strings"
+	"time"
+)
+
+// debIndexRe matches the binary Packages indexes a virtual merges: the flat
+// repo's root Packages and a suite's <component>/binary-<arch>/Packages.
+var debIndexRe = regexp.MustCompile(`^([^/]+/binary-[^/]+/)?Packages(\.[a-z0-9]+)?$`)
+
+// debByHashRe matches an index requested by its SHA256 (Acquire-By-Hash).
+var debByHashRe = regexp.MustCompile(`^([^/]+/binary-[^/]+/)?by-hash/SHA256/[0-9a-f]{64}$`)
+
+// debCompressions is the order a member's index variants are fetched in.
+var debCompressions = []string{".xz", ".gz", ".zst", ".bz2", ""}
+
+// DebMember is one member's Release plus its decompressed Packages indexes,
+// keyed by index directory relative to the Release ("" for a flat repo).
+type DebMember struct {
+	RemoteName string
+	Release    []byte
+	Packages   map[string][]byte
+}
+
+// DebRepo is a merged apt repo: Release plus the indexes it lists, keyed by
+// their path relative to the Release.
+type DebRepo struct {
+	Release []byte
+	Files   map[string][]byte
+}
+
+type debRelease struct {
+	fields map[string]string
+	files  []string
+}
+
+// parseDebRelease reads a Release file's single-line fields and the names
+// listed in its checksum sections.
+func parseDebRelease(body []byte) debRelease {
+	rel := debRelease{fields: map[string]string{}}
+	inSums := false
+	seen := map[string]bool{}
+	for line := range strings.SplitSeq(string(body), "\n") {
+		line = strings.TrimRight(line, "\r")
+		if line == "" {
+			continue
+		}
+		if line[0] == ' ' || line[0] == '\t' {
+			if f := strings.Fields(line); inSums && len(f) == 3 && !seen[f[2]] {
+				seen[f[2]] = true
+				rel.files = append(rel.files, f[2])
+			}
+			continue
+		}
+		k, v, _ := strings.Cut(line, ":")
+		v = strings.TrimSpace(v)
+		inSums = v == "" && (k == "MD5Sum" || strings.HasPrefix(k, "SHA"))
+		if _, ok := rel.fields[k]; !ok {
+			rel.fields[k] = v
+		}
+	}
+	return rel
+}
+
+// debIndexFiles returns, per index directory, the variant of its Packages file
+// to fetch from a member's Release listing.
+func debIndexFiles(rel debRelease) map[string]string {
+	listed := map[string]bool{}
+	for _, f := range rel.files {
+		listed[f] = true
+	}
+	out := map[string]string{}
+	for _, f := range rel.files {
+		m := debIndexRe.FindStringSubmatch(f)
+		if m == nil || out[m[1]] != "" {
+			continue
+		}
+		for _, c := range debCompressions {
+			if listed[m[1]+"Packages"+c] {
+				out[m[1]] = m[1] + "Packages" + c
+				break
+			}
+		}
+	}
+	return out
+}
+
+func splitStanzas(body []byte) []string {
+	var out []string
+	for s := range strings.SplitSeq(strings.ReplaceAll(string(body), "\r\n", "\n"), "\n\n") {
+		if s = strings.Trim(s, "\n"); s != "" {
+			out = append(out, s)
+		}
+	}
+	return out
+}
+
+func stanzaField(stanza, key string) string {
+	for line := range strings.SplitSeq(stanza, "\n") {
+		if k, v, ok := strings.Cut(line, ":"); ok && k == key {
+			return strings.TrimSpace(v)
+		}
+	}
+	return ""
+}
+
+func unionFields(dst []string, field string) []string {
+	for f := range strings.FieldsSeq(field) {
+		if !slices.Contains(dst, f) {
+			dst = append(dst, f)
+		}
+	}
+	return dst
+}
+
+func parseDebDate(s string) (time.Time, bool) {
+	for _, layout := range []string{time.RFC1123Z, time.RFC1123} {
+		if t, err := time.Parse(layout, s); err == nil {
+			return t, true
+		}
+	}
+	return time.Time{}, false
+}
+
+// MergeDeb merges members into one apt repo. Members are in priority order: the
+// first member to carry a (Package, Version, Architecture) in an index wins;
+// stanzas missing any of those are always kept. Filename is prefixed with the
+// owning member's name so the virtual can route downloads back to it.
+func MergeDeb(members []DebMember) *DebRepo {
+	var suite, codename string
+	var arches, comps, dirs []string
+	date := time.Unix(0, 0)
+	for _, m := range members {
+		rel := parseDebRelease(m.Release)
+		if suite == "" {
+			suite, codename = rel.fields["Suite"], rel.fields["Codename"]
+		}
+		arches = unionFields(arches, rel.fields["Architectures"])
+		comps = unionFields(comps, rel.fields["Components"])
+		if t, ok := parseDebDate(rel.fields["Date"]); ok && t.After(date) {
+			date = t
+		}
+		for d := range m.Packages {
+			if !slices.Contains(dirs, d) {
+				dirs = append(dirs, d)
+			}
+		}
+	}
+	slices.Sort(dirs)
+
+	repo := &DebRepo{Files: map[string][]byte{}}
+	for _, d := range dirs {
+		seen := map[string]bool{}
+		var b bytes.Buffer
+		for _, m := range members {
+			for _, s := range splitStanzas(m.Packages[d]) {
+				pkg, ver, arch := stanzaField(s, "Package"), stanzaField(s, "Version"), stanzaField(s, "Architecture")
+				if pkg != "" && ver != "" && arch != "" {
+					key := pkg + "\x00" + ver + "\x00" + arch
+					if seen[key] {
+						continue
+					}
+					seen[key] = true
+				}
+				if fn := stanzaField(s, "Filename"); fn != "" {
+					s = rewriteFilename(s, m.RemoteName+"/"+strings.TrimPrefix(path.Clean("/"+fn), "/"))
+				}
+				b.WriteString(s)
+				b.WriteString("\n\n")
+			}
+		}
+		gz := gzipDeterministic(b.Bytes())
+		repo.Files[d+"Packages"] = b.Bytes()
+		repo.Files[d+"Packages.gz"] = gz
+		repo.Files[d+"by-hash/SHA256/"+sha256Hex(b.Bytes())] = b.Bytes()
+		repo.Files[d+"by-hash/SHA256/"+sha256Hex(gz)] = gz
+	}
+
+	var r bytes.Buffer
+	if suite != "" {
+		fmt.Fprintf(&r, "Suite: %s\n", suite)
+	}
+	if codename != "" {
+		fmt.Fprintf(&r, "Codename: %s\n", codename)
+	}
+	fmt.Fprintf(&r, "Date: %s\n", date.UTC().Format(time.RFC1123Z))
+	fmt.Fprintf(&r, "Architectures: %s\n", strings.Join(arches, " "))
+	if len(comps) > 0 {
+		fmt.Fprintf(&r, "Components: %s\n", strings.Join(comps, " "))
+	}
+	r.WriteString("Acquire-By-Hash: yes\n")
+	for _, sec := range []struct {
+		name string
+		sum  func([]byte) string
+	}{{"MD5Sum", md5Hex}, {"SHA256", sha256Hex}} {
+		r.WriteString(sec.name + ":\n")
+		for _, d := range dirs {
+			for _, n := range []string{d + "Packages", d + "Packages.gz"} {
+				fmt.Fprintf(&r, " %s %d %s\n", sec.sum(repo.Files[n]), len(repo.Files[n]), n)
+			}
+		}
+	}
+	repo.Release = r.Bytes()
+	return repo
+}
+
+func rewriteFilename(stanza, fn string) string {
+	lines := strings.Split(stanza, "\n")
+	for i, l := range lines {
+		if strings.HasPrefix(l, "Filename:") {
+			lines[i] = "Filename: " + fn
+			break
+		}
+	}
+	return strings.Join(lines, "\n")
+}
+
+// debIndexPath splits an index request into its Release directory and the file
+// under it. ok is false for anything a deb virtual does not merge.
+func debIndexPath(p string) (base, name string, ok bool) {
+	if rest, found := strings.CutPrefix(p, "dists/"); found {
+		suite, n, found := strings.Cut(rest, "/")
+		if !found || suite == "" {
+			return "", "", false
+		}
+		base, p = "dists/"+suite+"/", n
+	}
+	if p != "Release" && !debIndexRe.MatchString(p) && !debByHashRe.MatchString(p) {
+		return "", "", false
+	}
+	return base, p, true
+}
+
+func md5Hex(data []byte) string {
+	h := md5.Sum(data)
+	return hex.EncodeToString(h[:])
+}

internal/virtual/deb_merger_test.go

@@ -0,0 +1,179 @@
+package virtual
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/hex"
+	"fmt"
+	"maps"
+	"path"
+	"slices"
+	"strings"
+	"testing"
+)
+
+func debStanza(pkg, ver, arch, filename string) string {
+	return fmt.Sprintf("Package: %s\nVersion: %s\nArchitecture: %s\nDescription: test\n multi-line body\nFilename: %s\nSize: 1\n", pkg, ver, arch, filename)
+}
+
+func flatDebMember(name, date string, stanzas ...string) DebMember {
+	rel := "Date: " + date + "\nArchitectures: amd64\nAcquire-By-Hash: no\nSHA256:\n x 1 Packages\n x 1 Packages.gz\n"
+	return DebMember{RemoteName: name, Release: []byte(rel), Packages: map[string][]byte{"": []byte(strings.Join(stanzas, "\n"))}}
+}
+
+func TestMergeDebDedupesByMemberOrder(t *testing.T) {
+	repo := MergeDeb([]DebMember{
+		flatDebMember("a", "Mon, 05 Oct 2026 10:00:00 +0000",
+			debStanza("foo", "1.0", "amd64", "pool/foo_1.0_amd64.deb"),
+			debStanza("bar", "2.0", "amd64", "/pool/bar.deb"),
+			debStanza("dot", "1.0", "amd64", "./dot.deb"),
+			"Package: noversion\nFilename: nv1.deb\n",
+			"Package: noversion\nFilename: nv2.deb\n"),
+		flatDebMember("b", "Tue, 06 Oct 2026 10:00:00 UTC",
+			debStanza("foo", "1.0", "amd64", "pool/foo-from-b.deb"),
+			debStanza("foo", "1.0", "arm64", "pool/foo_arm64.deb"),
+			debStanza("foo", "1.1", "amd64", "o/r/releases/download/v1/foo.deb")),
+	})
+	pk := string(repo.Files["Packages"])
+	stanzas := splitStanzas(repo.Files["Packages"])
+	if len(stanzas) != 7 {
+		t.Fatalf("want 7 stanzas (one duplicate dropped), got %d:\n%s", len(stanzas), pk)
+	}
+	for _, want := range []string{
+		"Filename: a/pool/foo_1.0_amd64.deb",
+		"Filename: a/pool/bar.deb",
+		"Filename: a/dot.deb",
+		"Filename: a/nv1.deb",
+		"Filename: a/nv2.deb",
+		"Filename: b/pool/foo_arm64.deb",
+		"Filename: b/o/r/releases/download/v1/foo.deb",
+		" multi-line body",
+	} {
+		if !strings.Contains(pk, want) {
+			t.Errorf("merged Packages missing %q:\n%s", want, pk)
+		}
+	}
+	if strings.Contains(pk, "foo-from-b") {
+		t.Fatalf("second member's duplicate must lose:\n%s", pk)
+	}
+	if !bytes.Equal(gunzip(t, repo.Files["Packages.gz"]), repo.Files["Packages"]) {
+		t.Fatal("Packages.gz does not match Packages")
+	}
+	if !strings.Contains(string(repo.Release), "Date: Tue, 06 Oct 2026 10:00:00 +0000\n") {
+		t.Fatalf("Date should be the newest member date:\n%s", repo.Release)
+	}
+}
+
+func TestMergeDebReleaseHashesFiles(t *testing.T) {
+	repo := MergeDeb([]DebMember{flatDebMember("a", "", debStanza("foo", "1", "amd64", "pool/foo.deb"))})
+	rel := parseDebRelease(repo.Release)
+	if got := slices.Sorted(slices.Values(rel.files)); !slices.Equal(got, []string{"Packages", "Packages.gz"}) {
+		t.Fatalf("Release lists %v", got)
+	}
+	inSHA := false
+	checked := 0
+	for line := range strings.SplitSeq(string(repo.Release), "\n") {
+		if !strings.HasPrefix(line, " ") {
+			inSHA = line == "SHA256:"
+			continue
+		}
+		var sum, name string
+		var size int
+		if _, err := fmt.Sscan(line, &sum, &size, &name); err != nil {
+			t.Fatal(err)
+		}
+		body := repo.Files[name]
+		want := sha256Hex(body)
+		if !inSHA {
+			h := md5.Sum(body)
+			want = hex.EncodeToString(h[:])
+		}
+		if sum != want || size != len(body) {
+			t.Errorf("%s: Release has %s %d, file is %s %d", name, sum, size, want, len(body))
+		}
+		checked++
+	}
+	if checked != 4 {
+		t.Fatalf("checked %d Release entries, want 4:\n%s", checked, repo.Release)
+	}
+	if !bytes.Equal(MergeDeb([]DebMember{flatDebMember("a", "", debStanza("foo", "1", "amd64", "pool/foo.deb"))}).Release, repo.Release) {
+		t.Fatal("merge must be deterministic")
+	}
+}
+
+func TestMergeDebSuiteLayout(t *testing.T) {
+	rel := func(comps string) []byte {
+		return []byte("Suite: stable\nCodename: trixie\nArchitectures: amd64 arm64\nComponents: " + comps + "\nSHA256:\n x 1 main/binary-amd64/Packages.xz\n")
+	}
+	repo := MergeDeb([]DebMember{
+		{RemoteName: "deb1", Release: rel("main"), Packages: map[string][]byte{"main/binary-amd64/": []byte(debStanza("foo", "1", "amd64", "pool/main/f/foo.deb"))}},
+		{RemoteName: "deb2", Release: rel("main contrib"), Packages: map[string][]byte{
+			"main/binary-amd64/":    []byte(debStanza("bar", "1", "amd64", "pool/main/b/bar.deb")),
+			"contrib/binary-amd64/": []byte(debStanza("baz", "1", "amd64", "pool/contrib/b/baz.deb")),
+		}},
+	})
+	for _, want := range []string{"Suite: stable\n", "Codename: trixie\n", "Components: main contrib\n", "Architectures: amd64 arm64\n"} {
+		if !strings.Contains(string(repo.Release), want) {
+			t.Errorf("Release missing %q:\n%s", want, repo.Release)
+		}
+	}
+	want := []string{"contrib/binary-amd64/Packages", "contrib/binary-amd64/Packages.gz", "main/binary-amd64/Packages", "main/binary-amd64/Packages.gz"}
+	if got := slices.Sorted(slices.Values(parseDebRelease(repo.Release).files)); !slices.Equal(got, want) {
+		t.Fatalf("Release lists %v, want %v", got, want)
+	}
+	if !strings.Contains(string(repo.Release), "Acquire-By-Hash: yes\n") {
+		t.Fatalf("Release must advertise by-hash:\n%s", repo.Release)
+	}
+	for _, n := range want {
+		byHash := path.Dir(n) + "/by-hash/SHA256/" + sha256Hex(repo.Files[n])
+		if !bytes.Equal(repo.Files[byHash], repo.Files[n]) {
+			t.Errorf("%s not served at %s", n, byHash)
+		}
+	}
+	if len(repo.Files) != 2*len(want) {
+		t.Fatalf("files %v, want each index plus its by-hash copy", slices.Sorted(maps.Keys(repo.Files)))
+	}
+	if n := len(splitStanzas(repo.Files["main/binary-amd64/Packages"])); n != 2 {
+		t.Fatalf("main/binary-amd64 should merge both members, got %d stanzas", n)
+	}
+}
+
+func TestDebIndexFiles(t *testing.T) {
+	rel := parseDebRelease([]byte("Origin: Debian\nMD5Sum:\n a 1 main/binary-amd64/Packages\n a 1 main/binary-amd64/Packages.gz\nSHA256:\n" +
+		" a 1 main/binary-amd64/Packages\n a 1 main/binary-amd64/Packages.xz\n a 1 main/binary-amd64/Packages.gz\n" +
+		" a 1 main/debian-installer/binary-amd64/Packages.xz\n a 1 main/i18n/Translation-en.xz\n a 1 contrib/binary-all/Packages\n"))
+	got := debIndexFiles(rel)
+	want := map[string]string{"main/binary-amd64/": "main/binary-amd64/Packages.xz", "contrib/binary-all/": "contrib/binary-all/Packages"}
+	if !maps.Equal(got, want) {
+		t.Fatalf("got %v, want %v", got, want)
+	}
+	if flat := debIndexFiles(parseDebRelease([]byte("SHA256:\n a 1 Packages\n a 1 Packages.gz\n"))); flat[""] != "Packages.gz" {
+		t.Fatalf("flat repo should fetch Packages.gz, got %v", flat)
+	}
+}
+
+func TestDebIndexPath(t *testing.T) {
+	for _, tc := range []struct {
+		in, base, name string
+		ok             bool
+	}{
+		{"Release", "", "Release", true},
+		{"Packages.gz", "", "Packages.gz", true},
+		{"dists/trixie/Release", "dists/trixie/", "Release", true},
+		{"dists/trixie/main/binary-amd64/Packages", "dists/trixie/", "main/binary-amd64/Packages", true},
+		{"by-hash/SHA256/abababababababababababababababababababababababababababababababab", "", "by-hash/SHA256/abababababababababababababababababababababababababababababababab", true},
+		{"dists/trixie/main/binary-amd64/by-hash/SHA256/abababababababababababababababababababababababababababababababab", "dists/trixie/", "main/binary-amd64/by-hash/SHA256/abababababababababababababababababababababababababababababababab", true},
+		{"dists/trixie/main/binary-amd64/by-hash/MD5Sum/abababababababababababababababab", "", "", false},
+		{"InRelease", "", "", false},
+		{"Release.gpg", "", "", false},
+		{"dists/trixie/InRelease", "", "", false},
+		{"dists/trixie/main/i18n/Translation-en", "", "", false},
+		{"dists/Release", "", "", false},
+		{"pool/foo.deb", "", "", false},
+	} {
+		base, name, ok := debIndexPath(tc.in)
+		if base != tc.base || name != tc.name || ok != tc.ok {
+			t.Errorf("%s: got (%q, %q, %v), want (%q, %q, %v)", tc.in, base, name, ok, tc.base, tc.name, tc.ok)
+		}
+	}
+}

internal/virtual/engine.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"path"
 	"slices"
 	"strings"
 	"sync"
@@ -26,6 +27,7 @@ type Engine struct {
 	proxyEngine *proxy.Engine
 	getRemote   func(context.Context, string) (*models.Remote, error)
 	rpmMember   func(context.Context, string) (*RPMMember, error)
+	debMember   func(ctx context.Context, name, base string) (*DebMember, error)
 	npmMember   func(ctx context.Context, name, pkg string) (*NPMMember, error)
 
 	// NPMLocal returns a local npm repo's packument with tarball paths relative
@@ -45,6 +47,8 @@ type Engine struct {
 
 	goMember func(ctx context.Context, name, path string) (*GoMember, error)
 
+	puppetDoc func(ctx context.Context, remote models.Remote, path string) ([]byte, error)
+
 	mergeTTL time.Duration
 
 	sf   singleflight.Group
@@ -60,29 +64,39 @@ type mergedRepo interface {
 
 func (r *RPMRepo) index() []byte            { return r.Repomd }
 func (r *RPMRepo) files() map[string][]byte { return r.Files }
+func (r *DebRepo) index() []byte            { return r.Release }
+func (r *DebRepo) files() map[string][]byte { return r.Files }
 
 // repoGen holds a virtual's current merge plus the previous one, so a client
 // holding the previous index can still fetch the files it references.
 type repoGen struct {
 	cur, prev mergedRepo
-	at        time.Time
+	at, used  time.Time
 }
 
 const rpmMergeTTL = 60 * time.Second
 
+// maxDebSuites bounds the client-chosen suites cached per deb virtual.
+const maxDebSuites = 32
+
 func NewEngine(db *database.DB, proxyEngine *proxy.Engine) *Engine {
 	e := &Engine{db: db, proxyEngine: proxyEngine, getRemote: db.GetRemote, mergeTTL: rpmMergeTTL}
 	e.rpmMember = e.fetchRPMMember
+	e.debMember = e.fetchDebMember
 	e.npmMember = e.fetchNPMMember
 	e.gemsMember = e.fetchGemsMember
 	e.ansibleDoc = e.ansibleMemberDoc
 	e.goMember = e.fetchGoMember
+	e.puppetDoc = e.fetchMemberPath
 	return e
 }
 
 func (e *Engine) Fetch(ctx context.Context, virt models.Virtual, path string, proxyBaseURL string) ([]byte, string, error) {
-	if virt.PackageType == models.PackageRPM {
+	switch virt.PackageType {
+	case models.PackageRPM:
 		return e.fetchRPM(ctx, virt, path)
+	case models.PackageDeb:
+		return e.fetchDeb(ctx, virt, path)
 	}
 
 	merger, err := GetMerger(virt.PackageType)
@@ -201,16 +215,22 @@ var (
 	ErrBadPath  = errors.New("invalid path")
 )
 
-// MemberRedirect maps an rpm, npm or ansible virtual package path
+// MemberRedirect maps an rpm, deb, npm or ansible virtual package path
-// (<member>/<href>, as written by MergeRPM/MergeNPM/AnsibleVersion) to the
+// (<member>/<href>, as written by MergeRPM/MergeDeb/MergeNPM/AnsibleVersion)
-// owning member's route. ok is false for any other path; ErrBadPath means the
+// to the owning member's route. ok is false for any other path; ErrBadPath
-// path is absolute or escapes the member.
+// means the path is absolute or escapes the member.
 func (e *Engine) MemberRedirect(ctx context.Context, virt models.Virtual, path, rawQuery, proxyBaseURL string) (string, bool, error) {
 	switch virt.PackageType {
 	case models.PackageRPM:
 		if strings.HasPrefix(path, "repodata/") {
 			return "", false, nil
 		}
+	case models.PackageDeb:
+		// apt requests a flat repo's files under its "./" dist verbatim.
+		path = strings.TrimPrefix(path, "./")
+		if strings.HasPrefix(path, "dists/") {
+			return "", false, nil
+		}
 	case models.PackageNPM, models.PackageAnsible:
 	default:
 		return "", false, nil
@@ -291,6 +311,7 @@ func (e *Engine) merged(ctx context.Context, key string, merge func(context.Cont
 	e.mu.Lock()
 	g := e.gens[key]
 	if g != nil && time.Since(g.at) < e.mergeTTL {
+		g.used = time.Now()
 		e.mu.Unlock()
 		return g.cur, nil
 	}
@@ -309,12 +330,12 @@ func (e *Engine) merged(ctx context.Context, key string, merge func(context.Cont
 		g := e.gens[key]
 		switch {
 		case g == nil:
-			e.gens[key] = &repoGen{cur: repo, at: time.Now()}
+			e.gens[key] = &repoGen{cur: repo, at: time.Now(), used: time.Now()}
 		case string(g.cur.index()) == string(repo.index()):
-			g.at = time.Now()
+			g.at, g.used = time.Now(), time.Now()
 			repo = g.cur
 		default:
-			g.prev, g.cur, g.at = g.cur, repo, time.Now()
+			g.prev, g.cur, g.at, g.used = g.cur, repo, time.Now(), time.Now()
 		}
 		return repo, nil
 	})
@@ -361,6 +382,85 @@ func fetchMembers[T any](virt models.Virtual, fetch func(name string) (*T, error
 	return members, nil
 }
 
+func (e *Engine) fetchDeb(ctx context.Context, virt models.Virtual, reqPath string) ([]byte, string, error) {
+	base, name, ok := debIndexPath(strings.TrimPrefix(path.Clean("/"+reqPath), "/"))
+	if !ok {
+		return nil, "", ErrNotFound
+	}
+	key := "deb\x00" + virt.Name + "\x00" + base
+	if name != "Release" {
+		if body, ok := e.cachedFile(key, name); ok {
+			return body, debContentType(name), nil
+		}
+	}
+
+	repo, err := e.merged(ctx, key, func(ctx context.Context) (mergedRepo, error) {
+		members, err := fetchMembers(virt, func(name string) (*DebMember, error) { return e.debMember(ctx, name, base) })
+		if err != nil {
+			return nil, err
+		}
+		return MergeDeb(members), nil
+	})
+	if err != nil {
+		return nil, "", err
+	}
+	e.evictLRU("deb\x00"+virt.Name+"\x00", maxDebSuites)
+	if name == "Release" {
+		return repo.index(), "text/plain", nil
+	}
+	if body, ok := repo.files()[name]; ok {
+		return body, debContentType(name), nil
+	}
+	return nil, "", ErrNotFound
+}
+
+func debContentType(name string) string {
+	if strings.HasSuffix(name, ".gz") {
+		return "application/gzip"
+	}
+	return "text/plain"
+}
+
+// fetchDebMember reads a member's Release under base and each binary Packages
+// index it lists.
+func (e *Engine) fetchDebMember(ctx context.Context, name, base string) (*DebMember, error) {
+	remote, err := e.getRemote(ctx, name)
+	if err != nil {
+		return nil, fmt.Errorf("remote %q: %w", name, err)
+	}
+	rel, err := e.fetchMemberPath(ctx, *remote, base+"Release")
+	if err != nil {
+		return nil, err
+	}
+	m := &DebMember{RemoteName: name, Release: rel, Packages: map[string][]byte{}}
+	for dir, file := range debIndexFiles(parseDebRelease(rel)) {
+		raw, err := e.fetchMemberPath(ctx, *remote, base+file)
+		if err != nil {
+			return nil, err
+		}
+		if m.Packages[dir], err = decompress(file, raw); err != nil {
+			return nil, fmt.Errorf("decompress %s: %w", file, err)
+		}
+	}
+	return m, nil
+}
+
+// evictLRU drops the least recently used merges under prefix beyond keep.
+func (e *Engine) evictLRU(prefix string, keep int) {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	var keys []string
+	for k := range e.gens {
+		if strings.HasPrefix(k, prefix) {
+			keys = append(keys, k)
+		}
+	}
+	slices.SortFunc(keys, func(a, b string) int { return e.gens[b].used.Compare(e.gens[a].used) })
+	for _, k := range keys[min(len(keys), keep):] {
+		delete(e.gens, k)
+	}
+}
+
 func (e *Engine) cachedFile(key, path string) ([]byte, bool) {
 	e.mu.Lock()
 	defer e.mu.Unlock()
@@ -373,6 +473,7 @@ func (e *Engine) cachedFile(key, path string) ([]byte, bool) {
 			continue
 		}
 		if body, ok := r.files()[path]; ok {
+			g.used = time.Now()
 			return body, true
 		}
 	}
@@ -419,8 +520,9 @@ func (e *Engine) fetchMemberPath(ctx context.Context, remote models.Remote, path
 		if !ok {
 			return nil, fmt.Errorf("provider %q does not serve a local index", remote.PackageType)
 		}
+		reqPath, _, _ := strings.Cut(path, "?")
 		serve = func(w http.ResponseWriter, r *http.Request) bool {
-			return indexer.ServeLocalIndex(w, r, e.db, remote.Name, path)
+			return indexer.ServeLocalIndex(w, r, e.db, remote.Name, reqPath)
 		}
 	} else if rs, ok := prov.(provider.RemoteServer); ok {
 		serve = func(w http.ResponseWriter, r *http.Request) bool {

internal/virtual/engine_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"regexp"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"testing"
@@ -157,6 +158,97 @@ func TestMemberRedirect(t *testing.T) {
 	}
 }
 
+func debEngine(members map[string]*DebMember) *Engine {
+	e := fakeEngine(nil)
+	e.debMember = func(_ context.Context, name, base string) (*DebMember, error) {
+		if m := members[name]; m != nil && base == "" {
+			return m, nil
+		}
+		return nil, errors.New("upstream down")
+	}
+	return e
+}
+
+func debVirt(members ...string) models.Virtual {
+	return models.Virtual{Name: "v", PackageType: models.PackageDeb, Members: members}
+}
+
+func TestFetchDebFailsClosed(t *testing.T) {
+	a := flatDebMember("a", "", debStanza("foo", "1", "amd64", "pool/foo.deb"))
+	e := debEngine(map[string]*DebMember{"a": &a})
+	for _, p := range []string{"Release", "./Packages.gz", "dists/trixie/Release"} {
+		if _, _, err := e.Fetch(context.Background(), debVirt("a", "b"), p, ""); err == nil || errors.Is(err, ErrNotFound) {
+			t.Errorf("%s: want upstream error with a member down, got %v", p, err)
+		}
+	}
+	for _, p := range []string{"InRelease", "./Release.gpg", "Packages.xz"} {
+		if _, _, err := e.Fetch(context.Background(), debVirt("a"), p, ""); !errors.Is(err, ErrNotFound) {
+			t.Errorf("%s: want not found, got %v", p, err)
+		}
+	}
+}
+
+func TestFetchDebRemergesAfterTTL(t *testing.T) {
+	a := flatDebMember("a", "", debStanza("foo", "1", "amd64", "pool/foo_1.deb"))
+	e := debEngine(map[string]*DebMember{"a": &a})
+	virt := debVirt("a")
+
+	rel, _, err := e.Fetch(context.Background(), virt, "./Release", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	a.Packages[""] = []byte(debStanza("foo", "2", "amd64", "pool/foo_2.deb"))
+	e.mergeTTL = 0
+	newRel, _, err := e.Fetch(context.Background(), virt, "Release", "")
+	if err != nil || string(newRel) == string(rel) {
+		t.Fatalf("Release should reflect the member change (err %v)", err)
+	}
+	pk, ct, err := e.Fetch(context.Background(), virt, "./Packages", "")
+	if err != nil || ct != "text/plain" || !strings.Contains(string(pk), "Version: 2") {
+		t.Fatalf("Packages should be the current merge (ct %q, err %v):\n%s", ct, err, pk)
+	}
+}
+
+func TestFetchDebMergeIsSharedPerSuite(t *testing.T) {
+	var calls atomic.Int32
+	e := fakeEngine(nil)
+	e.mergeTTL = time.Minute
+	e.debMember = func(_ context.Context, name, base string) (*DebMember, error) {
+		calls.Add(1)
+		m := flatDebMember(name, "", debStanza("foo", "1", "amd64", "pool/foo.deb"))
+		return &m, nil
+	}
+	for _, p := range []string{"Release", "Packages", "Packages.gz", "./Release", "dists/a/Release", "dists/b/Release"} {
+		if _, _, err := e.Fetch(context.Background(), debVirt("a"), p, ""); err != nil && !errors.Is(err, ErrNotFound) {
+			t.Fatal(err)
+		}
+	}
+	if n := calls.Load(); n != 3 {
+		t.Fatalf("member fetched %d times, want once per Release dir (3)", n)
+	}
+}
+
+func TestMemberRedirectDeb(t *testing.T) {
+	e := fakeEngine(nil)
+	virt := debVirt("gh", "loc")
+	for _, tc := range []struct {
+		path, want string
+		ok         bool
+		err        error
+	}{
+		{path: "gh/o/r/releases/download/v1/foo_1.0_amd64.deb", ok: true, want: "http://h/api/v1/remote/gh/o/r/releases/download/v1/foo_1.0_amd64.deb"},
+		{path: "./gh/pool/a+b.deb", ok: true, want: "http://h/api/v1/remote/gh/pool/a+b.deb"},
+		{path: "gh/../loc/x.deb", err: ErrBadPath},
+		{path: "dists/trixie/Release"},
+		{path: "Packages"},
+	} {
+		got, ok, err := e.MemberRedirect(context.Background(), virt, tc.path, "", "http://h/")
+		if got != tc.want || ok != tc.ok || !errors.Is(err, tc.err) {
+			t.Errorf("%s: got (%q, %v, %v), want (%q, %v, %v)", tc.path, got, ok, err, tc.want, tc.ok, tc.err)
+		}
+	}
+}
+
 type fakeRepo struct {
 	idx string
 	fs  map[string][]byte
@@ -206,3 +298,72 @@ func TestMergedReusesWithinTTLAndIsolatesKeys(t *testing.T) {
 		t.Error("unknown key served a file")
 	}
 }
+
+func suiteDebMember(name, version string) *DebMember {
+	return &DebMember{RemoteName: name, Release: []byte("Suite: s\nSHA256:\n x 1 main/binary-amd64/Packages.gz\n"),
+		Packages: map[string][]byte{"main/binary-amd64/": []byte(debStanza("foo", version, "amd64", "pool/foo_"+version+".deb"))}}
+}
+
+func TestFetchDebByHashSurvivesRemerge(t *testing.T) {
+	version := "1"
+	e := fakeEngine(nil)
+	e.debMember = func(_ context.Context, name, _ string) (*DebMember, error) { return suiteDebMember(name, version), nil }
+	virt := debVirt("a")
+	fetch := func(p string) []byte {
+		body, _, err := e.Fetch(context.Background(), virt, p, "")
+		if err != nil {
+			t.Fatalf("%s: %v", p, err)
+		}
+		return body
+	}
+	byHash := func(rel []byte) string {
+		m := regexp.MustCompile(`(?m)^SHA256:\n(?: .*\n)*? ([0-9a-f]{64}) \d+ main/binary-amd64/Packages.gz$`).FindSubmatch(rel)
+		if m == nil {
+			t.Fatalf("no Packages.gz SHA256 in Release:\n%s", rel)
+		}
+		return "dists/trixie/main/binary-amd64/by-hash/SHA256/" + string(m[1])
+	}
+
+	oldRel := fetch("dists/trixie/Release")
+	version, e.mergeTTL = "2", 0
+	if newRel := fetch("dists/trixie/Release"); string(newRel) == string(oldRel) {
+		t.Fatal("Release should reflect the member change")
+	}
+	if got := string(gunzip(t, fetch(byHash(oldRel)))); !strings.Contains(got, "Version: 1\n") {
+		t.Fatalf("by-hash from the previous Release served the wrong index:\n%s", got)
+	}
+	if got := string(fetch("dists/trixie/main/binary-amd64/Packages")); !strings.Contains(got, "Version: 2\n") {
+		t.Fatalf("fixed-name Packages should be the current merge:\n%s", got)
+	}
+}
+
+func TestFetchDebBoundsSuitesPerVirtual(t *testing.T) {
+	e := fakeEngine(nil)
+	e.mergeTTL = time.Minute
+	e.debMember = func(_ context.Context, name, _ string) (*DebMember, error) { return suiteDebMember(name, "1"), nil }
+	other := models.Virtual{Name: "other", PackageType: models.PackageDeb, Members: []string{"a"}}
+	if _, _, err := e.Fetch(context.Background(), other, "dists/keep/Release", ""); err != nil {
+		t.Fatal(err)
+	}
+	for i := range maxDebSuites + 5 {
+		if _, _, err := e.Fetch(context.Background(), debVirt("a"), fmt.Sprintf("dists/s%d/Release", i), ""); err != nil {
+			t.Fatal(err)
+		}
+		time.Sleep(time.Microsecond)
+	}
+	n := 0
+	for k := range e.gens {
+		if strings.HasPrefix(k, "deb\x00v\x00") {
+			n++
+		}
+	}
+	if n != maxDebSuites {
+		t.Fatalf("virtual v caches %d suites, want %d", n, maxDebSuites)
+	}
+	if e.gens["deb\x00v\x00dists/s0/"] != nil || e.gens["deb\x00v\x00dists/s4/"] != nil {
+		t.Fatal("least recently used suites should be evicted first")
+	}
+	if e.gens["deb\x00other\x00dists/keep/"] == nil {
+		t.Fatal("another virtual's suites must not be evicted")
+	}
+}

internal/virtual/puppet_merger.go

@@ -0,0 +1,210 @@
+package virtual
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"maps"
+	"net/http"
+	"net/url"
+	"path"
+	"slices"
+	"strconv"
+	"strings"
+
+	"git.unkin.net/unkin/artifactapi/internal/provider/puppet"
+	"git.unkin.net/unkin/artifactapi/internal/proxy"
+	"git.unkin.net/unkin/artifactapi/pkg/models"
+)
+
+const (
+	maxPuppetModules     = 1024
+	puppetMemberPage     = 100
+	maxPuppetMemberPages = 100
+)
+
+// PuppetMember is one member's releases of a module; Found is false when the
+// member does not have it.
+type PuppetMember struct {
+	RemoteName string
+	Found      bool
+	Releases   []map[string]any
+}
+
+// PuppetDoc is a module's merged releases, newest version first, with
+// file_uri routed via the virtual; Owners maps each version to its member;
+// missing caches that no member has the module.
+type PuppetDoc struct {
+	Releases []map[string]any
+	Owners   map[string]string
+	body     []byte
+	missing  bool
+}
+
+func (d *PuppetDoc) index() []byte            { return d.body }
+func (d *PuppetDoc) files() map[string][]byte { return nil }
+
+// MergePuppetReleases merges member releases of slug; the earlier member wins
+// a duplicate version. A release whose file is not <slug>-<version>.tar.gz is
+// dropped, since its download could not be routed. ErrNotFound means no
+// member has the module.
+func MergePuppetReleases(slug string, members []PuppetMember) (*PuppetDoc, error) {
+	d := &PuppetDoc{Releases: []map[string]any{}, Owners: map[string]string{}}
+	found := false
+	for _, m := range members {
+		found = found || m.Found
+		for _, r := range m.Releases {
+			v, _ := r["version"].(string)
+			file, _ := r["file_uri"].(string)
+			name := path.Base(file)
+			s, fv, ok := puppet.ParseRelease(strings.TrimSuffix(name, ".tar.gz"))
+			if !ok || s != slug || fv != v || !strings.HasSuffix(name, ".tar.gz") {
+				continue
+			}
+			if _, dup := d.Owners[v]; dup {
+				continue
+			}
+			d.Owners[v] = m.RemoteName
+			r["file_uri"] = "/v3/files/" + name
+			d.Releases = append(d.Releases, r)
+		}
+	}
+	if !found {
+		return nil, ErrNotFound
+	}
+	slices.SortStableFunc(d.Releases, func(a, b map[string]any) int {
+		return puppet.CompareSemver(b["version"].(string), a["version"].(string))
+	})
+	var err error
+	d.body, err = json.Marshal(d.Releases)
+	return d, err
+}
+
+// PuppetModule is the /v3/modules/<slug> document for d: the newest release
+// as current_release and every release listed.
+func PuppetModule(d *PuppetDoc) (map[string]any, error) {
+	if len(d.Releases) == 0 {
+		return nil, ErrNotFound
+	}
+	top := d.Releases[0]
+	ref, ok := top["module"].(map[string]any)
+	if !ok {
+		return nil, fmt.Errorf("release %v has no module", top["slug"])
+	}
+	mod := maps.Clone(ref)
+	releases := make([]map[string]any, len(d.Releases))
+	for i, r := range d.Releases {
+		releases[i] = map[string]any{}
+		for _, k := range []string{"uri", "slug", "version", "file_uri", "file_size", "supported", "created_at", "deleted_at"} {
+			releases[i][k] = r[k]
+		}
+	}
+	mod["current_release"] = top
+	mod["releases"] = releases
+	return mod, nil
+}
+
+// PuppetReleases returns the merged releases of slug across members.
+func (e *Engine) PuppetReleases(ctx context.Context, virt models.Virtual, slug string) (*PuppetDoc, error) {
+	prefix := "puppet\x00" + virt.Name + "\x00"
+	inserted := false
+	repo, err := e.merged(ctx, prefix+slug, func(ctx context.Context) (mergedRepo, error) {
+		inserted = true
+		members, err := fetchMembers(virt, func(m string) (*PuppetMember, error) { return e.puppetMember(ctx, m, slug) })
+		if err != nil {
+			return nil, err
+		}
+		d, err := MergePuppetReleases(slug, members)
+		if errors.Is(err, ErrNotFound) {
+			return &PuppetDoc{missing: true}, nil
+		}
+		return d, err
+	})
+	if err != nil {
+		return nil, err
+	}
+	if inserted {
+		e.evictOldest(prefix, maxPuppetModules)
+	}
+	if d := repo.(*PuppetDoc); !d.missing {
+		return d, nil
+	}
+	return nil, ErrNotFound
+}
+
+// PuppetRedirect maps v3/releases/<slug>-<version> or v3/files/<file> to the
+// route of the member owning that release.
+func (e *Engine) PuppetRedirect(ctx context.Context, virt models.Virtual, p, proxyBaseURL string) (string, error) {
+	rel, ok := strings.CutPrefix(p, "v3/releases/")
+	if !ok {
+		file, isFile := strings.CutPrefix(p, "v3/files/")
+		if rel, ok = strings.CutSuffix(file, ".tar.gz"); !isFile || !ok {
+			return "", ErrNotFound
+		}
+	}
+	slug, version, ok := puppet.ParseRelease(rel)
+	if !ok {
+		return "", ErrNotFound
+	}
+	d, err := e.PuppetReleases(ctx, virt, slug)
+	if err != nil {
+		return "", err
+	}
+	owner, ok := d.Owners[version]
+	if !ok {
+		return "", ErrNotFound
+	}
+	loc, ok, err := e.memberLocation(ctx, owner, p, "", proxyBaseURL)
+	if err != nil {
+		return "", err
+	}
+	if !ok {
+		return "", fmt.Errorf("member %q not found", owner)
+	}
+	return loc, nil
+}
+
+// puppetMember reads every release a member lists for slug, following its
+// pagination.
+func (e *Engine) puppetMember(ctx context.Context, member, slug string) (*PuppetMember, error) {
+	remote, err := e.getRemote(ctx, member)
+	if err != nil {
+		return nil, fmt.Errorf("remote %q: %w", member, err)
+	}
+	m := &PuppetMember{RemoteName: member}
+	q := url.Values{"module": {slug}, "limit": {strconv.Itoa(puppetMemberPage)}, "exclude_fields": {"readme changelog license reference"}}
+	for page := 0; page < maxPuppetMemberPages; page++ {
+		if page > 0 {
+			q.Set("offset", strconv.Itoa(len(m.Releases)))
+		}
+		p := "v3/releases?" + q.Encode()
+		body, err := e.puppetDoc(ctx, *remote, p)
+		var pe *proxy.ProxyError
+		if errors.Is(err, ErrNotFound) || errors.As(err, &pe) && pe.Status == http.StatusNotFound {
+			return m, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		var doc struct {
+			Pagination struct{ Total int }
+			Results    []map[string]any
+		}
+		dec := json.NewDecoder(bytes.NewReader(body))
+		dec.UseNumber()
+		if err := dec.Decode(&doc); err != nil {
+			return nil, fmt.Errorf("%s/%s: %v", member, p, err)
+		}
+		m.Found = m.Found || doc.Pagination.Total > 0
+		m.Releases = append(m.Releases, doc.Results...)
+		if len(m.Releases) >= doc.Pagination.Total {
+			return m, nil
+		}
+		if len(doc.Results) == 0 {
+			return nil, fmt.Errorf("%s/%s: empty page after %d of %d releases", member, p, len(m.Releases), doc.Pagination.Total)
+		}
+	}
+	return nil, fmt.Errorf("%s: more than %d pages of %s releases", member, maxPuppetMemberPages, slug)
+}

internal/virtual/puppet_merger_test.go

@@ -0,0 +1,205 @@
+package virtual
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/url"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"git.unkin.net/unkin/artifactapi/internal/proxy"
+	"git.unkin.net/unkin/artifactapi/pkg/models"
+)
+
+func puppetRel(slug, version string) map[string]any {
+	return map[string]any{
+		"slug": slug + "-" + version, "version": version,
+		"file_uri": "/v3/files/" + slug + "-" + version + ".tar.gz",
+		"module":   map[string]any{"slug": slug, "uri": "/v3/modules/" + slug},
+	}
+}
+
+func versionsOf(rs []map[string]any) string {
+	var out []string
+	for _, r := range rs {
+		out = append(out, r["version"].(string))
+	}
+	return strings.Join(out, ",")
+}
+
+func TestMergePuppetReleases(t *testing.T) {
+	absolute := puppetRel("unkin-hello", "0.3.0")
+	absolute["file_uri"] = "https://forge.example/api/v1/remote/forge/v3/files/unkin-hello-0.3.0.tar.gz"
+	internalDup := puppetRel("unkin-hello", "0.2.0")
+	internalDup["tag"] = "internal"
+	wrongFile := puppetRel("unkin-hello", "9.0.0")
+	wrongFile["file_uri"] = "/v3/files/unkin-other-9.0.0.tar.gz"
+
+	d, err := MergePuppetReleases("unkin-hello", []PuppetMember{
+		{RemoteName: "internal", Found: true, Releases: []map[string]any{puppetRel("unkin-hello", "0.1.0"), internalDup}},
+		{RemoteName: "missing"},
+		{RemoteName: "forge", Found: true, Releases: []map[string]any{absolute, puppetRel("unkin-hello", "0.2.0"), puppetRel("unkin-hello", "0.10.0"), wrongFile, puppetRel("unkin-other", "1.0.0")}},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := versionsOf(d.Releases); got != "0.10.0,0.3.0,0.2.0,0.1.0" {
+		t.Fatalf("merged = %s, want newest semver first without foreign or misnamed releases", got)
+	}
+	for v, owner := range map[string]string{"0.1.0": "internal", "0.2.0": "internal", "0.3.0": "forge", "0.10.0": "forge"} {
+		if d.Owners[v] != owner {
+			t.Errorf("owner of %s = %q, want %q", v, d.Owners[v], owner)
+		}
+	}
+	if d.Releases[2]["tag"] != "internal" {
+		t.Errorf("duplicate 0.2.0 not taken from the first member: %v", d.Releases[2])
+	}
+	if d.Releases[1]["file_uri"] != "/v3/files/unkin-hello-0.3.0.tar.gz" {
+		t.Errorf("file_uri = %v, want routed via the virtual", d.Releases[1]["file_uri"])
+	}
+
+	mod, err := PuppetModule(d)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if mod["slug"] != "unkin-hello" || mod["current_release"].(map[string]any)["version"] != "0.10.0" || len(mod["releases"].([]map[string]any)) != 4 {
+		t.Fatalf("module = %v", mod)
+	}
+
+	if _, err := MergePuppetReleases("unkin-hello", []PuppetMember{{RemoteName: "a"}, {RemoteName: "b"}}); !errors.Is(err, ErrNotFound) {
+		t.Fatalf("no member has it: want ErrNotFound, got %v", err)
+	}
+}
+
+// forgePages answers a member's /v3/releases like the Forge, two per page.
+func forgePages(slug string, versions []string, p string) ([]byte, error) {
+	_, raw, _ := strings.Cut(p, "?")
+	q, _ := url.ParseQuery(raw)
+	offset, _ := strconv.Atoi(q.Get("offset"))
+	end := min(offset+2, len(versions))
+	var results []map[string]any
+	for _, v := range versions[min(offset, end):end] {
+		results = append(results, puppetRel(slug, v))
+	}
+	return json.Marshal(map[string]any{"pagination": map[string]int{"total": len(versions)}, "results": results})
+}
+
+func puppetEngine(doc func(remote models.Remote, path string) ([]byte, error)) *Engine {
+	return &Engine{
+		mergeTTL: time.Minute,
+		getRemote: func(_ context.Context, name string) (*models.Remote, error) {
+			rt := models.RepoTypeRemote
+			if name == "internal" {
+				rt = models.RepoTypeLocal
+			}
+			return &models.Remote{Name: name, RepoType: rt}, nil
+		},
+		puppetDoc: func(_ context.Context, remote models.Remote, path string) ([]byte, error) { return doc(remote, path) },
+	}
+}
+
+func TestPuppetReleasesFollowsMemberPages(t *testing.T) {
+	var mu sync.Mutex
+	var asked []string
+	e := puppetEngine(func(remote models.Remote, p string) ([]byte, error) {
+		mu.Lock()
+		asked = append(asked, remote.Name+" "+p)
+		mu.Unlock()
+		switch remote.Name {
+		case "internal":
+			return forgePages("puppetlabs-stdlib", []string{"9.6.0"}, p)
+		case "gone":
+			return nil, &proxy.ProxyError{Status: 404}
+		}
+		return forgePages("puppetlabs-stdlib", []string{"9.6.0", "9.5.0", "9.4.0", "8.0.0", "7.0.0"}, p)
+	})
+	virt := models.Virtual{Name: "puppet", PackageType: models.PackagePuppet, Members: []string{"internal", "gone", "forge"}}
+	d, err := e.PuppetReleases(context.Background(), virt, "puppetlabs-stdlib")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if versionsOf(d.Releases) != "9.6.0,9.5.0,9.4.0,8.0.0,7.0.0" || d.Owners["9.6.0"] != "internal" || d.Owners["7.0.0"] != "forge" {
+		t.Fatalf("merged = %s %v", versionsOf(d.Releases), d.Owners)
+	}
+	if len(asked) != 5 {
+		t.Fatalf("want 1 internal + 1 gone + 3 forge pages, asked %v", asked)
+	}
+	for _, a := range asked {
+		if strings.HasPrefix(a, "forge ") && !strings.Contains(a, "module=puppetlabs-stdlib") {
+			t.Errorf("member page without module filter: %q", a)
+		}
+	}
+	if _, err := e.PuppetReleases(context.Background(), virt, "puppetlabs-stdlib"); err != nil || len(asked) != 5 {
+		t.Fatalf("merge not cached: %v, %d fetches", err, len(asked))
+	}
+}
+
+func TestPuppetReleasesFailsClosed(t *testing.T) {
+	for name, doc := range map[string]func(models.Remote, string) ([]byte, error){
+		"member error": func(r models.Remote, p string) ([]byte, error) {
+			if r.Name == "forge" {
+				return nil, &proxy.ProxyError{Status: 503}
+			}
+			return forgePages("unkin-hello", []string{"0.1.0"}, p)
+		},
+		"short member list": func(models.Remote, string) ([]byte, error) {
+			return []byte(`{"pagination":{"total":3},"results":[]}`), nil
+		},
+	} {
+		e := puppetEngine(doc)
+		virt := models.Virtual{Name: "puppet", PackageType: models.PackagePuppet, Members: []string{"internal", "forge"}}
+		if _, err := e.PuppetReleases(context.Background(), virt, "unkin-hello"); err == nil || errors.Is(err, ErrNotFound) {
+			t.Errorf("%s: want a non-404 error, got %v", name, err)
+		}
+	}
+}
+
+func TestPuppetRedirect(t *testing.T) {
+	e := puppetEngine(func(r models.Remote, p string) ([]byte, error) {
+		if r.Name == "internal" {
+			return forgePages("unkin-hello", []string{"0.1.0"}, p)
+		}
+		return forgePages("unkin-hello", []string{"0.2.0", "0.1.0"}, p)
+	})
+	virt := models.Virtual{Name: "puppet", PackageType: models.PackagePuppet, Members: []string{"internal", "forge"}}
+	for p, want := range map[string]string{
+		"v3/files/unkin-hello-0.1.0.tar.gz": "https://a.example/api/v1/local/internal/v3/files/unkin-hello-0.1.0.tar.gz",
+		"v3/releases/unkin-hello-0.2.0":     "https://a.example/api/v1/remote/forge/v3/releases/unkin-hello-0.2.0",
+	} {
+		if loc, err := e.PuppetRedirect(context.Background(), virt, p, "https://a.example"); err != nil || loc != want {
+			t.Errorf("%s -> %q %v, want %q", p, loc, err, want)
+		}
+	}
+	for _, p := range []string{"v3/files/unkin-hello-0.3.0.tar.gz", "v3/files/unkin-hello-0.1.0.zip", "v3/releases/nope", "v3/users/unkin"} {
+		if _, err := e.PuppetRedirect(context.Background(), virt, p, "https://a.example"); !errors.Is(err, ErrNotFound) {
+			t.Errorf("%s: want ErrNotFound, got %v", p, err)
+		}
+	}
+}
+
+func TestPuppetReleasesCachesMissingModule(t *testing.T) {
+	var mu sync.Mutex
+	asked := map[string]int{}
+	e := puppetEngine(func(r models.Remote, p string) ([]byte, error) {
+		mu.Lock()
+		asked[r.Name]++
+		mu.Unlock()
+		if r.Name == "internal" {
+			return nil, &proxy.ProxyError{Status: 404}
+		}
+		return forgePages("unkin-nope", nil, p)
+	})
+	virt := models.Virtual{Name: "puppet", PackageType: models.PackagePuppet, Members: []string{"internal", "forge"}}
+	for range 2 {
+		if _, err := e.PuppetReleases(context.Background(), virt, "unkin-nope"); !errors.Is(err, ErrNotFound) {
+			t.Fatalf("want ErrNotFound, got %v", err)
+		}
+	}
+	if asked["internal"] != 1 || asked["forge"] != 1 {
+		t.Fatalf("a module no member has must be cached, asked %v", asked)
+	}
+}