appview/repo: allow viewing unreachable repos

instead of showing a 503 indiscriminately, we now indicate that the knot
is unreachable and display a warning. the user is still free to browse
issues and pulls.

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

appview/pages/pages.go

···
 	Languages        []types.RepoLanguageDetails
 	Pipelines        map[string]models.Pipeline
 	NeedsKnotUpgrade bool
+	KnotUnreachable  bool
 	types.RepoIndexResponse
 }
 
···
 
 	if params.NeedsKnotUpgrade {
 		return p.executeRepo("repo/needsUpgrade", w, params)
+	}
+
+	if params.KnotUnreachable {
+		return p.executeRepo("repo/knotUnreachable", w, params)
 	}
 
 	p.rctx.RepoInfo = params.RepoInfo

appview/pages/templates/repo/knotUnreachable.html

···
+{{ define "title" }}{{ .RepoInfo.FullName }}{{ end }}
+{{ define "extrameta" }}
+    {{ template "repo/fragments/meta" . }}
+    {{ template "repo/fragments/og" (dict "RepoInfo" .RepoInfo) }}
+{{ end }}
+{{ define "repoContent" }}
+  <main>
+    <div class="relative w-full h-96 flex items-center justify-center">
+      <div class="absolute inset-0 flex items-center justify-center py-12 text-red-500 dark:text-red-400 backdrop-blur">
+        <div class="text-center">
+          {{ i "triangle-alert" "size-5 inline-flex items-center align-middle" }}
+          The knot hosting this repository is unreachable.
+        </div>
+      </div>
+    </div>
+  </main>
+{{ end }}
+

appview/repo/index.go

···
 				RepoInfo:         rp.repoResolver.GetRepoInfo(r, user),
 			})
 			return
+		} else {
+			l.Error("failed to build index response", "err", err)
+			rp.pages.RepoIndexPage(w, pages.RepoIndexParams{
+				LoggedInUser:    user,
+				KnotUnreachable: true,
+				RepoInfo:        rp.repoResolver.GetRepoInfo(r, user),
+			})
+			return
 		}
-
-		rp.pages.Error503(w)
-		l.Error("failed to build index response", "err", err)
-		return
 	}
 
 	tagMap := make(map[string][]string)
···
 	)
 
 	// tags
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		tagsBytes, err := tangled.RepoTags(ctx, xrpcc, "", 0, didSlashRepo)
 		if err != nil {
 			errs = errors.Join(errs, fmt.Errorf("failed to call repoTags: %w", err))
···
 		if err := json.Unmarshal(tagsBytes, &tagsResp); err != nil {
 			errs = errors.Join(errs, fmt.Errorf("failed to unmarshal repoTags: %w", err))
 		}
-	}()
+	})
 
 	// tree/files
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		resp, err := tangled.RepoTree(ctx, xrpcc, "", ref, didSlashRepo)
 		if err != nil {
 			errs = errors.Join(errs, fmt.Errorf("failed to call repoTree: %w", err))
 			return
 		}
 		treeResp = resp
-	}()
+	})
 
 	// commits
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		logBytes, err := tangled.RepoLog(ctx, xrpcc, "", 50, "", ref, didSlashRepo)
 		if err != nil {
 			errs = errors.Join(errs, fmt.Errorf("failed to call repoLog: %w", err))
···
 		if err := json.Unmarshal(logBytes, &logResp); err != nil {
 			errs = errors.Join(errs, fmt.Errorf("failed to unmarshal repoLog: %w", err))
 		}
-	}()
+	})
 
 	wg.Wait()
 

appview/repo/settings.go

···
 
 	repo := fmt.Sprintf("%s/%s", f.Did, f.Name)
 	xrpcBytes, err := tangled.RepoBranches(r.Context(), xrpcc, "", 0, repo)
+	var result types.RepoBranchesResponse
 	if xrpcerr := xrpcclient.HandleXrpcErr(err); xrpcerr != nil {
 		l.Error("failed to call XRPC repo.branches", "err", xrpcerr)
-		rp.pages.Error503(w)
-		return
-	}
-
-	var result types.RepoBranchesResponse
-	if err := json.Unmarshal(xrpcBytes, &result); err != nil {
+	} else if err := json.Unmarshal(xrpcBytes, &result); err != nil {
 		l.Error("failed to decode XRPC response", "err", err)
 		rp.pages.Error503(w)
 		return