appview: relax auth requirement on artifact download

Signed-off-by: oppiliappan <[e-mail]>

appview/repo/artifact.go

···
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"net/url"
···
 	})
 }
 
-// TODO: proper statuses here on early exit
 func (rp *Repo) DownloadArtifact(w http.ResponseWriter, r *http.Request) {
-	tagParam := chi.URLParam(r, "tag")
-	filename := chi.URLParam(r, "file")
 	f, err := rp.repoResolver.Resolve(r)
 	if err != nil {
 		log.Println("failed to get repo and knot", err)
+		http.Error(w, "failed to resolve repo", http.StatusInternalServerError)
 		return
 	}
+
+	tagParam := chi.URLParam(r, "tag")
+	filename := chi.URLParam(r, "file")
 
 	tag, err := rp.resolveTag(r.Context(), f, tagParam)
 	if err != nil {
···
 		return
 	}
 
-	client, err := rp.oauth.AuthorizedClient(r)
-	if err != nil {
-		log.Println("failed to get authorized client", err)
-		return
-	}
-
 	artifacts, err := db.GetArtifact(
 		rp.db,
 		db.FilterEq("repo_at", f.RepoAt()),
···
 	)
 	if err != nil {
 		log.Println("failed to get artifacts", err)
+		http.Error(w, "failed to get artifact", http.StatusInternalServerError)
 		return
 	}
+
 	if len(artifacts) != 1 {
-		log.Printf("too many or too little artifacts found")
+		log.Printf("too many or too few artifacts found")
+		http.Error(w, "artifact not found", http.StatusNotFound)
 		return
 	}
 
 	artifact := artifacts[0]
 
-	getBlobResp, err := client.SyncGetBlob(r.Context(), artifact.BlobCid.String(), artifact.Did)
+	ownerPds := f.OwnerId.PDSEndpoint()
+	url, _ := url.Parse(fmt.Sprintf("%s/xrpc/com.atproto.sync.getBlob", ownerPds))
+	q := url.Query()
+	q.Set("cid", artifact.BlobCid.String())
+	q.Set("did", artifact.Did)
+	url.RawQuery = q.Encode()
+
+	req, err := http.NewRequest(http.MethodGet, url.String(), nil)
+	if err != nil {
+		log.Println("failed to create request", err)
+		http.Error(w, "failed to create request", http.StatusInternalServerError)
+		return
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
-		log.Println("failed to get blob from pds", err)
+		log.Println("failed to make request", err)
+		http.Error(w, "failed to make request to PDS", http.StatusInternalServerError)
 		return
 	}
+	defer resp.Body.Close()
 
-	w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=%q", filename))
-	w.Write(getBlobResp)
+	// copy status code and relevant headers from upstream response
+	w.WriteHeader(resp.StatusCode)
+	for key, values := range resp.Header {
+		for _, v := range values {
+			w.Header().Add(key, v)
+		}
+	}
+
+	// stream the body directly to the client
+	if _, err := io.Copy(w, resp.Body); err != nil {
+		log.Println("error streaming response to client:", err)
+	}
 }
 
 // TODO: proper statuses here on early exit

appview/repo/router.go

···
 	r.Route("/tags", func(r chi.Router) {
 		r.Get("/", rp.RepoTags)
 		r.Route("/{tag}", func(r chi.Router) {
-			r.Use(middleware.AuthMiddleware(rp.oauth))
-			// require auth to download for now
 			r.Get("/download/{file}", rp.DownloadArtifact)
 
 			// require repo:push to upload or delete artifacts
···
 			// additionally: only the uploader can truly delete an artifact
 			// (record+blob will live on their pds)
 			r.Group(func(r chi.Router) {
-				r.With(mw.RepoPermissionMiddleware("repo:push"))
+				r.Use(middleware.AuthMiddleware(rp.oauth))
+				r.Use(mw.RepoPermissionMiddleware("repo:push"))
 				r.Post("/upload", rp.AttachArtifact)
 				r.Delete("/{file}", rp.DeleteArtifact)
 			})