fix(gmail): stop hiding why it failed, twice over

Reported from use: "Fetch now" said "something went wrong" and the error log was
empty. Both halves were the same bug wearing two hats.

`handleGmailSyncNow` answered 502 with the code `internal_error`, which the
interface maps to a generic sentence — so Google's own words, which are the whole
diagnosis, were replaced by one that says nothing. And `writeError` records
nothing; only `s.internal` does. So there was no message to read and nowhere to
look it up afterwards.

`s.upstream()` is the answer: 502 because this is somebody else's service saying
no rather than this server breaking, a code of its own so the interface can quote
what was said, and a row in the error log — which is the entire reason that log
exists. A Gmail sync failing quietly for a week is otherwise invisible: the
background job writes a line the next restart erases.

The same connection also left the mailbox unnamed. The address is learned at
connect time and that call can fail; a warning went to the log and an empty string
to the database, so the page said "an unknown account" and kept saying it. The only
way back was to disconnect and reconnect, which nobody would guess. The status
endpoint asks again when it finds none, so a wrong answer lasts until the next look
rather than until somebody reconnects.

Ten Danish strings were hiding in `confirm()` and `app.toast()` calls, including
every destructive confirmation in the app — the worst possible set to leave in one
language, since it is what somebody reads in the half-second before agreeing to
lose something. The i18n guard reads markup and attributes, and a string argument
lives in the script block. It reads those now, and found four my own grep missed.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

internal/httpapi/auth_handlers.go

@@ -573,6 +573,34 @@ func inboxName(locale string) string {
 // 11:49" long after the line explaining it has gone, which tells an operator that
 // something broke and gives them no way to find out what. The row outlives the
 // container; Indstillinger → Fejl is where it is read.
+// upstream reports a failure that came from somebody else's service.
+//
+// Separate from `internal` because the cause is different and so is the fix: a 500
+// is this server broken, and this is Google — or whoever — saying no. The status
+// says so (502), and the message is passed through rather than replaced, because
+// "invalid_grant" or "insufficient authentication scopes" is the whole diagnosis
+// and a generic sentence in its place throws it away.
+//
+// It is recorded like a 500 for exactly the reason the error log exists: a Gmail
+// sync that has been failing for a week is invisible otherwise. The background job
+// writes a log line the next restart erases, and nobody is watching the one screen
+// that would have said so.
+func (s *Server) upstream(w http.ResponseWriter, r *http.Request, code, what string, err error) {
+	s.log.Warn(what, "err", err)
+
+	userID := ""
+	if u := userFrom(r.Context()); u != nil {
+		userID = u.ID
+	}
+	s.db.RecordError(r.Context(), store.ServerError{
+		Method: r.Method, Path: r.URL.Path, Status: http.StatusBadGateway,
+		What: what, Message: err.Error(), UserID: userID,
+		RequestID: middleware.GetReqID(r.Context()),
+	})
+
+	writeError(w, http.StatusBadGateway, code, err.Error())
+}
+
 func (s *Server) internal(w http.ResponseWriter, r *http.Request, what string, err error) {
 	s.log.Error(what, "err", err)
 

internal/httpapi/errors.go

@@ -51,6 +51,13 @@ const (
 	// is not "that already exists" either, and it is the one refusal on the user
 	// page that a person needs explained rather than merely reported.
 	CodeLastAdmin = "last_admin"
+
+	// Gmail said no. Its own words are the diagnosis — "invalid_grant",
+	// "insufficient authentication scopes" — and they are useless behind a generic
+	// sentence, which is what `internal_error` gave: a person clicked Fetch now,
+	// read "something went wrong", and had nowhere to go. The interface wraps the
+	// message in one that says where it came from.
+	CodeGmailFailed = "gmail_failed"
 )
 
 // errLastAdmin is returned to the caller that already wrote the response, so it

internal/httpapi/gmail_handlers.go

@@ -150,6 +150,9 @@ func (s *Server) handleGmailCallback(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Best effort: a mailbox that connects but cannot name itself is still
+	// connected, and the status endpoint asks again when it finds no address —
+	// so this failing is a delay rather than a dead end.
 	email, err := gmail.NewClient(token.AccessToken).Profile(r.Context())
 	if err != nil {
 		s.log.Warn("gmail profile", "err", err)
@@ -184,7 +187,7 @@ func (s *Server) handleGmailSyncNow(w http.ResponseWriter, r *http.Request) {
 
 	created, err := s.SyncGmail(r.Context(), user)
 	if err != nil {
-		writeError(w, http.StatusBadGateway, CodeInternal, err.Error())
+		s.upstream(w, r, CodeGmailFailed, "sync gmail", err)
 		return
 	}
 	writeJSON(w, http.StatusOK, map[string]int{"created": created})
@@ -425,3 +428,39 @@ func (s *Server) handleSetGmailClient(w http.ResponseWriter, r *http.Request) {
 	}
 	w.WriteHeader(http.StatusNoContent)
 }
+
+// gmailProfile fetches the mailbox address and stores it, refreshing the access
+// token first if it has expired.
+//
+// Shared by the connect callback and the status endpoint. The callback is the
+// natural place to learn the address, and it is also the one moment that cannot be
+// retried — so the status endpoint asks again when it finds nothing, and the answer
+// corrects itself on the next look.
+func (s *Server) gmailProfile(ctx context.Context, user *store.User, settings map[string]any) (string, error) {
+	str := func(key string) string {
+		v, _ := settings[key].(string)
+		return v
+	}
+
+	access := str("access_token")
+	expires, _ := settings["expires_at"].(float64)
+	if access == "" || int64(expires) <= time.Now().Unix() {
+		token, err := s.gmailConfig(ctx).Refresh(ctx, str("refresh_token"))
+		if err != nil {
+			return "", err
+		}
+		access = token.AccessToken
+		settings["access_token"] = access
+		settings["expires_at"] = token.ExpiresAt.Unix()
+	}
+
+	email, err := gmail.NewClient(access).Profile(ctx)
+	if err != nil {
+		return "", err
+	}
+	settings["email"] = email
+	if err := s.db.SetUserSettings(ctx, user.ID, "gmail", settings); err != nil {
+		return "", err
+	}
+	return email, nil
+}

internal/httpapi/gmail_test.go

@@ -0,0 +1,70 @@
+package httpapi
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/kristianwind/verdande/internal/config"
+)
+
+// A Gmail failure has to survive being reported.
+//
+// It used to be hidden twice over. The handler answered 502 with the code
+// `internal_error`, which the interface maps to "something went wrong" — so
+// Google's own words, the only thing that says what to do, were replaced by a
+// sentence that says nothing. And `writeError` records nothing, so the error log
+// was empty: a person clicked Fetch now, read a generic failure, and there was
+// nowhere to look it up afterwards.
+func TestAGmailFailureSaysWhatGmailSaidAndIsRecorded(t *testing.T) {
+	// A Gmail that refuses, the way an expired grant does.
+	google := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, `{"error":"invalid_grant"}`, http.StatusBadRequest)
+	}))
+	defer google.Close()
+
+	ts := newTestServerWith(t, func(cfg *config.Config) {
+		cfg.GmailClientID = "test-client"
+		cfg.GmailClientSecret = "test-secret"
+	})
+	ts.bootstrap(t)
+
+	user, err := ts.db.UserByEmail(t.Context(), "kristian@example.dk")
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Connected, with a refresh token that will be refused.
+	if err := ts.db.SetUserSettings(t.Context(), user.ID, "gmail", map[string]any{
+		"refresh_token": "spent", "trigger": "starred",
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	resp, body := ts.do(t, "POST", "/api/v1/gmail/sync", nil)
+	if resp.StatusCode != http.StatusBadGateway {
+		t.Fatalf("sync: status %d, want 502 — this is Gmail saying no, not this server breaking",
+			resp.StatusCode)
+	}
+	if body["code"] != "gmail_failed" {
+		t.Errorf("code = %v, want gmail_failed — `internal_error` is mapped to a generic "+
+			"sentence, which throws the diagnosis away", body["code"])
+	}
+	if msg, _ := body["error"].(string); msg == "" {
+		t.Error("the message is empty; Gmail's own words are the whole diagnosis")
+	}
+
+	// And it is in the error log, which is the point of having one: a sync that has
+	// been failing for a week is invisible otherwise.
+	_, logged := ts.do(t, "GET", "/api/v1/errors", nil)
+	rows, _ := logged["errors"].([]any)
+	if len(rows) == 0 {
+		t.Fatal("nothing was recorded; the failure is as invisible as it was before")
+	}
+	row := rows[0].(map[string]any)
+	if row["what"] != "sync gmail" {
+		t.Errorf("what = %v, want \"sync gmail\"", row["what"])
+	}
+	if row["status"] != float64(http.StatusBadGateway) {
+		t.Errorf("status = %v, want 502", row["status"])
+	}
+}

internal/httpapi/integrations_handlers.go

@@ -379,9 +379,27 @@ func (s *Server) handleGetGmail(w http.ResponseWriter, r *http.Request) {
 		v, _ := values[key].(string)
 		return v
 	}
+	// The mailbox address, fetched again if it is missing.
+	//
+	// It is stored at connect time, and the call that fetches it can fail — a
+	// slow token, a scope Google had not applied yet. That failure used to be a
+	// log line and an empty string, so the page said "an unknown account" and went
+	// on saying it forever: the only way back was to disconnect and reconnect,
+	// which nobody would guess. Asking again here costs one request on a page
+	// nobody opens often, and it means the wrong answer lasts until the next look
+	// rather than until somebody reconnects.
+	email := str("email")
+	if email == "" && str("refresh_token") != "" {
+		if fetched, err := s.gmailProfile(r.Context(), userFrom(r.Context()), values); err == nil {
+			email = fetched
+		} else {
+			s.log.Warn("gmail profile", "err", err)
+		}
+	}
+
 	writeJSON(w, http.StatusOK, gmailSettings{
 		Connected: str("refresh_token") != "",
-		Email:     str("email"),
+		Email:     email,
 		Trigger:   str("trigger"),
 		Label:     str("label"),
 	})

internal/i18n/untranslated_test.go

@@ -20,6 +20,56 @@ import (
 // away whatever letters it happens to use. A word list rather than a language
 // detector: this repository ships one static binary, and a list of thirty common
 // words catches the sentences a person would actually write.
+// The same words, inside the code rather than the markup.
+//
+// `confirm()`, `alert()` and `app.toast()` take a string argument, and a string
+// argument lives in the script block where the scanner above never looks. Six of
+// them survived the whole i18n sweep that way — every destructive confirmation in
+// the app, which is the worst possible set to leave in one language, because it is
+// the text somebody reads in the half-second before they agree to lose something.
+func TestNoDanishProseInDialogsAndToasts(t *testing.T) {
+	// The argument of one of the three, quoted or backticked. Deliberately narrow:
+	// a general scan of every string literal in a Svelte script block would drown
+	// in class names, keys and query fragments.
+	call := regexp.MustCompile(`(?:confirm|alert|app\.toast)\(\s*['` + "`" + `]([^'` + "`" + `]{4,})['` + "`" + `]`)
+	danish := regexp.MustCompile(`(?i)\b(og|er|ikke|det|den|der|til|kan|som|har|med|af|en|et|du|din|dine|vises|ingen|nyere|fundet|ude|valgt|slettet|gemt|opgave|projekt|indstillinger|fjern|opret|vælg|luk|tilføj|ryd|gem|slet|omdøb|bliver|holder|alle)\b`)
+
+	var found []string
+	root := filepath.Join("..", "..", "web", "src")
+	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
+		if err != nil || info.IsDir() {
+			return err
+		}
+		if !strings.HasSuffix(path, ".svelte") && !strings.HasSuffix(path, ".js") {
+			return nil
+		}
+		if strings.Contains(path, "locales") {
+			return nil
+		}
+		body, err := os.ReadFile(path)
+		if err != nil {
+			return err
+		}
+		rel, _ := filepath.Rel(root, path)
+		for _, m := range call.FindAllStringSubmatch(string(body), -1) {
+			if danish.MatchString(m[1]) {
+				found = append(found, rel+": "+m[1])
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("walk %s: %v", root, err)
+	}
+
+	if len(found) > 0 {
+		t.Errorf("%d dialog or toast string(s) are written in Danish inside the code. "+
+			"They are what somebody reads before agreeing to lose something, and an "+
+			"English interface shows them in Danish:\n  %s",
+			len(found), strings.Join(found, "\n  "))
+	}
+}
+
 func TestNoDanishProseOutsideTheDictionaries(t *testing.T) {
 	// Text nodes of three characters or more, and the three attributes a person
 	// reads. Anything inside {…} is already an expression — usually a t() call —