Add npm virtual repositories

internal/api/v1/npm_virtual.go

@@ -0,0 +1,26 @@
+package v1
+
+import (
+	"context"
+	"encoding/json"
+
+	"git.unkin.net/unkin/artifactapi/internal/virtual"
+)
+
+// LocalNPMPackument serves a local npm repo's packument to npm virtuals, with
+// tarball paths relative to the repo.
+func (h *ProxyHandler) LocalNPMPackument(ctx context.Context, repo, pkg string) ([]byte, error) {
+	files, err := h.db.ListLocalFilesByPrefix(ctx, repo, pkg+"/-/")
+	if err != nil {
+		return nil, err
+	}
+	read := func(hash string) ([]byte, error) { return h.readLocalBlob(ctx, hash) }
+	doc, err := buildNPMPackument(pkg, files, read, "")
+	if err != nil {
+		return nil, err
+	}
+	if doc == nil {
+		return nil, virtual.ErrNotFound
+	}
+	return json.Marshal(doc)
+}

internal/api/v1/proxy.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"log/slog"
 	"net/http"
+	"strings"
 
 	"github.com/go-chi/chi/v5"
 
@@ -186,7 +187,14 @@ func (h *ProxyHandler) handleVirtual(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	body, contentType, err := h.virtualEngine.Fetch(r.Context(), *virt, path, proxyBaseURL)
+	var body []byte
+	var contentType string
+	if virt.PackageType == models.PackageNPM {
+		abbreviated := strings.Contains(r.Header.Get("Accept"), virtual.NPMAbbreviatedType)
+		body, contentType, err = h.virtualEngine.FetchNPM(r.Context(), *virt, path, proxyBaseURL, abbreviated)
+	} else {
+		body, contentType, err = h.virtualEngine.Fetch(r.Context(), *virt, path, proxyBaseURL)
+	}
 	if errors.Is(err, virtual.ErrNotFound) {
 		http.Error(w, "not found", http.StatusNotFound)
 		return