Commit d4ea40c36c
d4ea40c36cabc17bcc6881eaef769bffba821e97
parent: 03e34fb24d
Verified · cmc
cmc <hello@cleberg.net> · 2026-09-29 16:45 UTC
httpd: a command a limiter turned away is 503 with Retry-After on the API
Ref #308
Layout: unified · split
internal/control/control.go
+3
| @@ -71,6 +71,9 @@ type Ctx struct { |
| 71 | 71 | // Packs is the pack-generation limiter a command that runs git to |
| 72 | 72 | // produce an archive takes a slot from; nil is no limit. |
| 73 | 73 | Packs *packlimit.Limiter |
| 74 | // Busy is set when a limiter turned the command away, so the API |
| 75 | // can answer 503 with Retry-After rather than a failure. |
| 76 | Busy bool |
| 74 | 77 | } |
| 75 | 78 | |
| 76 | 79 | // SourceWeb is Ctx.Source for a request from a browser session. Its |
internal/control/explore.go
+1
| @@ -130,6 +130,7 @@ func runRepoDownload(c *Ctx, args []string) int { |
| 130 | 130 | transport = "api" |
| 131 | 131 | } |
| 132 | 132 | c.Packs.Refused(transport, principal, err) |
| 133 | c.Busy = true |
| 133 | 134 | if errors.Is(err, packlimit.ErrBusy) { |
| 134 | 135 | return c.fail(protocol.ExitFailure, "the server is busy: it is at its limit of concurrent clones and fetches; try again in a minute") |
| 135 | 136 | } |
internal/httpd/api.go
+8
| @@ -97,12 +97,20 @@ func (s *Server) apiCmd(w http.ResponseWriter, r *http.Request) { |
| 97 | 97 | body["stderr"] = msg |
| 98 | 98 | } |
| 99 | 99 | w.Header().Set("Content-Type", "application/json") |
| 100 | if ctx.Busy { |
| 101 | status = http.StatusServiceUnavailable |
| 102 | w.Header().Set("Retry-After", busyRetryAfter) |
| 103 | } |
| 100 | 104 | w.WriteHeader(status) |
| 101 | 105 | json.NewEncoder(w).Encode(body) |
| 102 | 106 | } |
| 103 | 107 | |
| 104 | 108 | // statusForExit maps a command's exit code onto an HTTP status, shared by |
| 105 | 109 | // both API surfaces so they cannot answer the same failure differently. |
| 110 | // busyRetryAfter is the Retry-After on a 503 for a command a limiter |
| 111 | // turned away. |
| 112 | const busyRetryAfter = "60" |
| 113 | |
| 106 | 114 | func statusForExit(code int) int { |
| 107 | 115 | switch code { |
| 108 | 116 | case protocol.ExitOK: |
internal/httpd/apibusy_test.go
added
+52
| @@ -0,0 +1,52 @@ |
| 1 | package httpd |
| 2 | |
| 3 | import ( |
| 4 | "net/http" |
| 5 | "net/http/httptest" |
| 6 | "strings" |
| 7 | "testing" |
| 8 | |
| 9 | "gitbay.org/gitbay/internal/control" |
| 10 | "gitbay.org/gitbay/internal/gitutil" |
| 11 | "gitbay.org/gitbay/internal/store" |
| 12 | ) |
| 13 | |
| 14 | // repo download turned away by a full pack limit is 503 with |
| 15 | // Retry-After on both API endpoints, not a 500. |
| 16 | func TestAPIBusyDownloadIs503(t *testing.T) { |
| 17 | s := busyServer(t) |
| 18 | s.apiLimit = newAPILimiter(0) |
| 19 | if err := gitutil.InitBare(control.RepoDir(s.cfg.Server.Root, "alice", "app"), "main", t.TempDir()); err != nil { |
| 20 | t.Fatal(err) |
| 21 | } |
| 22 | seed(t, s, 10) |
| 23 | alice, err := s.st.UserByUsername("alice") |
| 24 | if err != nil { |
| 25 | t.Fatal(err) |
| 26 | } |
| 27 | if err := s.st.CreateAPIToken(alice.ID, "t", store.HashToken("secret"), "full", nil, 0); err != nil { |
| 28 | t.Fatal(err) |
| 29 | } |
| 30 | check := func(what string, w *httptest.ResponseRecorder) { |
| 31 | t.Helper() |
| 32 | if w.Code != http.StatusServiceUnavailable || w.Header().Get("Retry-After") != "60" || |
| 33 | !strings.Contains(w.Body.String(), "busy") { |
| 34 | t.Fatalf("%s: status %d, Retry-After %q, body %s", what, w.Code, w.Header().Get("Retry-After"), w.Body.String()) |
| 35 | } |
| 36 | if w.Header().Get("ETag") != "" { |
| 37 | t.Fatalf("%s: a busy answer carries an ETag", what) |
| 38 | } |
| 39 | } |
| 40 | |
| 41 | r := httptest.NewRequest("POST", "/api/v1/cmd", strings.NewReader(`{"argv":["repo","download","alice/app"]}`)) |
| 42 | r.Header.Set("Authorization", "Bearer secret") |
| 43 | w := httptest.NewRecorder() |
| 44 | s.apiCmd(w, r) |
| 45 | check("POST", w) |
| 46 | |
| 47 | r = httptest.NewRequest("GET", "/api/v1/read?argv=repo&argv=download&argv=alice/app", nil) |
| 48 | r.Header.Set("Authorization", "Bearer secret") |
| 49 | w = httptest.NewRecorder() |
| 50 | s.apiRead(w, r) |
| 51 | check("GET", w) |
| 52 | } |
internal/httpd/apiread.go
+9
| @@ -82,6 +82,15 @@ func (s *Server) apiRead(w http.ResponseWriter, r *http.Request) { |
| 82 | 82 | return |
| 83 | 83 | } |
| 84 | 84 | |
| 85 | if ctx.Busy { |
| 86 | // Not cacheable: the next try may succeed. |
| 87 | w.Header().Set("Content-Type", "application/json") |
| 88 | w.Header().Set("Retry-After", busyRetryAfter) |
| 89 | w.WriteHeader(http.StatusServiceUnavailable) |
| 90 | w.Write(payload) |
| 91 | return |
| 92 | } |
| 93 | |
| 85 | 94 | // Responses are authorized per account, so the ETag is salted with the |
| 86 | 95 | // caller: two users asking the same question may get different answers, |
| 87 | 96 | // and neither should ever be served the other's. |