test: comprehensive dockerised end-to-end suite (#97)

Adds a black-box e2e suite that runs against the **built container image** via docker-compose (complementing the in-process `e2e/` testcontainers suite).

## What it does
`make docker-e2e` → `scripts/docker-e2e.sh`: builds the image, brings up the full stack (postgres, redis, minio, artifactapi) plus a static nginx **mock upstream** for hermetic caching, waits for `/health`, runs `go test -tags=dockere2e ./e2e-docker/...`, and tears everything down.

## Coverage
- **Repository lifecycle** — add / change / delete for remote, local and virtual repos.
- **Caching** — one immutable artifact for **each of the 10 remote package types** (generic, docker, helm, pypi, npm, rpm, alpine, puppet, terraform, goproxy) proxied through the mock upstream: first fetch `X-Artifact-Source: remote`, second `cache`, bytes verified against the origin fixture.
- **Local uploads** — generic (upload/download), pypi (wheel + generated `simple/` index), rpm (real package + **automatic repodata** generation).
- **Virtual repositories** — pypi simple-index merge and helm `index.yaml` merge across two members.

## Notes
- The artifactapi host port is parameterised (`ARTIFACTAPI_PORT`, default `8000`; the e2e run uses `8001`) so it does not collide with a locally-running instance. This is the only change to the production `docker-compose.yml`.
- Fixtures under `e2e-docker/fixtures/` are real package files (incl. a real RPM so repodata parsing works); a `.gitignore` negation tracks them over the global ignore of those extensions.

## Validation
Ran `make docker-e2e` locally: **all suites pass** against the containerised product.

---------

Co-authored-by: BenVincent <benvin@main.unkin.net>
Reviewed-on: #97
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>

e2e-docker/local_test.go

@@ -0,0 +1,93 @@
+//go:build dockere2e
+
+package e2edocker
+
+import (
+	"bytes"
+	"net/http"
+	"strings"
+	"testing"
+	"time"
+)
+
+func uploadFile(t *testing.T, repo, filePath string, body []byte, contentType string) {
+	t.Helper()
+	url := api("/api/v2/remotes/" + repo + "/files/" + filePath)
+	resp, respBody := doRequest(t, http.MethodPut, url, body, contentType)
+	if resp.StatusCode != http.StatusCreated {
+		t.Fatalf("upload %s: status %d: %s", filePath, resp.StatusCode, respBody)
+	}
+}
+
+// TestLocalGenericUpload uploads a generic file and downloads it back.
+func TestLocalGenericUpload(t *testing.T) {
+	createRepo(t, `{"name":"local-generic","package_type":"generic","repo_type":"local"}`)
+	defer deleteRepo(t, "local-generic")
+
+	content := []byte("artifactapi local generic upload payload")
+	uploadFile(t, "local-generic", "data/hello.bin", content, "application/octet-stream")
+
+	resp, body := doRequest(t, http.MethodGet, api("/api/v1/local/local-generic/data/hello.bin"), nil, "")
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("download: status %d: %s", resp.StatusCode, body)
+	}
+	if !bytes.Equal(body, content) {
+		t.Fatalf("downloaded content mismatch")
+	}
+}
+
+// TestLocalPyPIUpload uploads a wheel and validates the generated simple index.
+func TestLocalPyPIUpload(t *testing.T) {
+	createRepo(t, `{"name":"local-pypi","package_type":"pypi","repo_type":"local"}`)
+	defer deleteRepo(t, "local-pypi")
+
+	wheel := fixtureBytes(t, "packages/foo-1.0-py3-none-any.whl")
+	uploadFile(t, "local-pypi", "foo-1.0-py3-none-any.whl", wheel, "application/zip")
+
+	// Root index lists the package.
+	resp, body := doRequest(t, http.MethodGet, api("/api/v1/local/local-pypi/simple/"), nil, "")
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("simple index: status %d: %s", resp.StatusCode, body)
+	}
+	if !strings.Contains(string(body), "foo") {
+		t.Fatalf("simple index missing package 'foo': %s", body)
+	}
+
+	// Per-package index lists the wheel file.
+	resp, body = doRequest(t, http.MethodGet, api("/api/v1/local/local-pypi/simple/foo/"), nil, "")
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("package index: status %d: %s", resp.StatusCode, body)
+	}
+	if !strings.Contains(string(body), "foo-1.0-py3-none-any.whl") {
+		t.Fatalf("package index missing wheel: %s", body)
+	}
+
+	// The wheel downloads back byte-identical.
+	resp, body = doRequest(t, http.MethodGet, api("/api/v1/local/local-pypi/foo/foo-1.0-py3-none-any.whl"), nil, "")
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("download wheel: status %d: %s", resp.StatusCode, body)
+	}
+	if !bytes.Equal(body, wheel) {
+		t.Fatalf("wheel content mismatch")
+	}
+}
+
+// TestLocalRPMRepodata uploads a real RPM and validates that repodata is
+// generated automatically (the special rpm-local feature).
+func TestLocalRPMRepodata(t *testing.T) {
+	createRepo(t, `{"name":"local-rpm","package_type":"rpm","repo_type":"local"}`)
+	defer deleteRepo(t, "local-rpm")
+
+	rpm := fixtureBytes(t, "rpmrepo/Packages/e2e-testpkg-1.0-1.noarch.rpm")
+	uploadFile(t, "local-rpm", "e2e-testpkg-1.0-1.noarch.rpm", rpm, "application/x-rpm")
+
+	// repodata is generated asynchronously after upload; poll for it.
+	resp, body := getEventually(t, api("/api/v1/local/local-rpm/repodata/repomd.xml"), 15*time.Second)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("repomd.xml: status %d: %s", resp.StatusCode, body)
+	}
+	s := string(body)
+	if !strings.Contains(s, "<repomd") || !strings.Contains(s, "primary") {
+		t.Fatalf("repomd.xml not a valid repodata document: %s", s)
+	}
+}