fix(deps): bump x/text past GO-2026-5970

govulncheck reported GO-2026-5970 as called via golang.org/x/text v0.31.0
(reached through the DB driver). Bump to v0.39.0; x/sync moves to v0.21.0
as its required minimum. govulncheck ./...: 0 vulnerabilities.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

go.mod

@@ -33,9 +33,9 @@ require (
 	github.com/rogpeppe/go-internal v1.15.0 // indirect
 	github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8 // indirect
 	go.yaml.in/yaml/v2 v2.4.2 // indirect
-	golang.org/x/sync v0.18.0 // indirect
+	golang.org/x/sync v0.21.0 // indirect
 	golang.org/x/sys v0.41.0 // indirect
-	golang.org/x/text v0.31.0 // indirect
+	golang.org/x/text v0.39.0 // indirect
 	google.golang.org/protobuf v1.36.8 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -113,12 +113,12 @@ go.yaml.in/yaml/v2 v2.4.2 h1:DzmwEr2rDGHl7lsFgAHxmNz/1NlQ7xLIrlN2h5d1eGI=
 go.yaml.in/yaml/v2 v2.4.2/go.mod h1:081UH+NErpNdqlCXm3TtEran0rJZGxAYx9hb/ELlsPU=
 golang.org/x/oauth2 v0.36.0 h1:peZ/1z27fi9hUOFCAZaHyrpWG5lwe0RJEEEeH0ThlIs=
 golang.org/x/oauth2 v0.36.0/go.mod h1:YDBUJMTkDnJS+A4BP4eZBjCqtokkg1hODuPjwiGPO7Q=
-golang.org/x/sync v0.18.0 h1:kr88TuHDroi+UVf+0hZnirlk8o8T+4MrK6mr60WkH/I=
+golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
-golang.org/x/sync v0.18.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
 golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
 golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
-golang.org/x/text v0.31.0 h1:aC8ghyu4JhP8VojJ2lEHBnochRno1sgL6nEi9WGFGMM=
+golang.org/x/text v0.39.0 h1:UbZz4pLOvn600D6Oh6GGEI6VAmndrEBLv8/6BEXzyus=
-golang.org/x/text v0.31.0/go.mod h1:tKRAlv61yKIjGGHX/4tP1LTbc13YSec1pxVEWXzfoeM=
+golang.org/x/text v0.39.0/go.mod h1:3UwRclnC2g0TU9x8PZiyfOajCd1zaUNHF9cvqcQZ+ZM=
 golang.org/x/time v0.15.0 h1:bbrp8t3bGUeFOx08pvsMYRTCVSMk89u4tKbNOZbp88U=
 golang.org/x/time v0.15.0/go.mod h1:Y4YMaQmXwGQZoFaVFk4YpCt4FLQMYKZe9oeV/f4MSno=
 google.golang.org/protobuf v1.36.8 h1:xHScyCOEuuwZEc6UtSOvPbAT4zRh0xcNRYekJwfqyMc=

internal/web/oidc/discovery_retry_test.go

@@ -0,0 +1,61 @@
+package oidc_test
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+
+	"git.d-ma.be/mathias/tapir/internal/web/oidc"
+)
+
+func testConfig(issuer string) oidc.Config {
+	return oidc.Config{
+		Issuer:        issuer,
+		ClientID:      testClientID,
+		ClientSecret:  "test-client-secret",
+		RedirectURL:   "http://tapir.test/auth/callback",
+		SessionSecret: "test-session-secret-please-change",
+	}
+}
+
+// #59: a discovery 503 at start-up is retried instead of failing New.
+func TestNewRetriesDiscoveryAfter503UntilIssuerAnswers(t *testing.T) {
+	f := newFakeIssuer(t)
+	f.unavailableFor = 2
+
+	auth, err := oidc.New(context.Background(), testConfig(f.server.URL),
+		oidc.WithDiscoveryRetry(5, time.Millisecond))
+
+	require.NoError(t, err)
+	require.NotNil(t, auth)
+	require.Equal(t, int32(3), f.discoveryHits.Load())
+}
+
+func TestNewReturnsDiscoveryErrorAfterAttemptsExhausted(t *testing.T) {
+	f := newFakeIssuer(t)
+	f.unavailableFor = 1000
+
+	_, err := oidc.New(context.Background(), testConfig(f.server.URL),
+		oidc.WithDiscoveryRetry(3, time.Millisecond))
+
+	require.ErrorContains(t, err, "503")
+	require.Equal(t, int32(3), f.discoveryHits.Load())
+}
+
+func TestNewStopsDiscoveryBackoffWhenContextCancelled(t *testing.T) {
+	f := newFakeIssuer(t)
+	f.unavailableFor = 1000
+	ctx, cancel := context.WithTimeout(context.Background(), 50*time.Millisecond)
+	defer cancel()
+
+	start := time.Now()
+	_, err := oidc.New(ctx, testConfig(f.server.URL),
+		oidc.WithDiscoveryRetry(5, time.Hour))
+
+	require.True(t, errors.Is(err, context.DeadlineExceeded), "err = %v", err)
+	require.Less(t, time.Since(start), 5*time.Second)
+	require.Equal(t, int32(1), f.discoveryHits.Load())
+}

internal/web/oidc/oidc.go

@@ -57,6 +57,10 @@ const (
 	pendingTTL        = 10 * time.Minute
 	sessionCookie     = "tapir_session"
 	loginPath         = "/auth/login"
+
+	// Discovery retry (#59): 5 tries, 2+4+8+16 s back-off ≈ 30 s, then fail.
+	defaultDiscoveryAttempts = 5
+	defaultDiscoveryDelay    = 2 * time.Second
 )
 
 // DexAuth implements web.Auth against Dex.
@@ -70,6 +74,9 @@ type DexAuth struct {
 	sessionTTL time.Duration
 	now        func() time.Time
 	insecure   bool // tests only: drop the Secure attribute so cookies flow over http
+
+	discoveryAttempts int
+	discoveryDelay    time.Duration
 }
 
 var _ web.Auth = (*DexAuth)(nil)
@@ -96,14 +103,55 @@ func WithSessionTTL(ttl time.Duration) Option {
 	}
 }
 
+// WithDiscoveryRetry overrides the discovery attempt count and the initial
+// back-off delay (doubled after each failed attempt).
+func WithDiscoveryRetry(attempts int, delay time.Duration) Option {
+	return func(d *DexAuth) {
+		if attempts > 0 {
+			d.discoveryAttempts = attempts
+		}
+		if delay > 0 {
+			d.discoveryDelay = delay
+		}
+	}
+}
+
 // WithInsecureCookies drops the Secure cookie attribute. TEST ONLY — it lets
 // the session cookie travel over plain http; never use it in production.
 func WithInsecureCookies() Option {
 	return func(d *DexAuth) { d.insecure = true }
 }
 
-// New discovers the issuer and returns a configured DexAuth. ctx bounds the
+// discover runs OIDC discovery up to attempts times, doubling delay between
-// discovery request only.
+// tries (#59: an issuer briefly unavailable behind its proxy answered 503 and
+// serve exited). A cancelled ctx ends the back-off immediately with ctx's error.
+func discover(ctx context.Context, issuer string, attempts int, delay time.Duration) (*oidc.Provider, error) {
+	var lastErr error
+	for i := range attempts {
+		if i > 0 {
+			t := time.NewTimer(delay)
+			select {
+			case <-ctx.Done():
+				t.Stop()
+				return nil, fmt.Errorf("after %d attempts (last: %v): %w", i, lastErr, ctx.Err())
+			case <-t.C:
+			}
+			delay *= 2
+		}
+		p, err := oidc.NewProvider(ctx, issuer)
+		if err == nil {
+			return p, nil
+		}
+		lastErr = err
+		if ctx.Err() != nil {
+			return nil, fmt.Errorf("after %d attempts: %w", i+1, ctx.Err())
+		}
+	}
+	return nil, fmt.Errorf("after %d attempts: %w", attempts, lastErr)
+}
+
+// New discovers the issuer and returns a configured DexAuth. ctx bounds discovery,
+// including its retry back-off.
 func New(ctx context.Context, cfg Config, opts ...Option) (*DexAuth, error) {
 	for name, val := range map[string]string{
 		"issuer":         cfg.Issuer,
@@ -117,29 +165,31 @@ func New(ctx context.Context, cfg Config, opts ...Option) (*DexAuth, error) {
 		}
 	}
 
-	provider, err := oidc.NewProvider(ctx, cfg.Issuer)
-	if err != nil {
-		return nil, fmt.Errorf("oidc: discover issuer: %w", err)
-	}
-
 	d := &DexAuth{
-		cfg:      cfg,
+		cfg:               cfg,
-		verifier: provider.Verifier(&oidc.Config{ClientID: cfg.ClientID}),
+		pending:           newPendingStore(),
-		oauth: &oauth2.Config{
+		secret:            []byte(cfg.SessionSecret),
-			ClientID:     cfg.ClientID,
+		sessionTTL:        defaultSessionTTL,
-			ClientSecret: cfg.ClientSecret,
+		now:               time.Now,
-			Endpoint:     provider.Endpoint(),
+		discoveryAttempts: defaultDiscoveryAttempts,
-			RedirectURL:  cfg.RedirectURL,
+		discoveryDelay:    defaultDiscoveryDelay,
-			Scopes:       []string{oidc.ScopeOpenID, "profile", "email"},
-		},
-		pending:    newPendingStore(),
-		secret:     []byte(cfg.SessionSecret),
-		sessionTTL: defaultSessionTTL,
-		now:        time.Now,
 	}
 	for _, o := range opts {
 		o(d)
 	}
+
+	provider, err := discover(ctx, cfg.Issuer, d.discoveryAttempts, d.discoveryDelay)
+	if err != nil {
+		return nil, fmt.Errorf("oidc: discover issuer: %w", err)
+	}
+	d.verifier = provider.Verifier(&oidc.Config{ClientID: cfg.ClientID})
+	d.oauth = &oauth2.Config{
+		ClientID:     cfg.ClientID,
+		ClientSecret: cfg.ClientSecret,
+		Endpoint:     provider.Endpoint(),
+		RedirectURL:  cfg.RedirectURL,
+		Scopes:       []string{oidc.ScopeOpenID, "profile", "email"},
+	}
 	return d, nil
 }
 

internal/web/oidc/oidc_test.go

@@ -8,6 +8,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -34,6 +35,11 @@ type fakeIssuer struct {
 	sub   string
 	email string
 	nonce string
+
+	// discoveryHits counts requests to the discovery document; the first
+	// unavailableFor of them answer 503 (issuer briefly down behind its proxy).
+	discoveryHits  atomic.Int32
+	unavailableFor int32
 }
 
 const testKID = "test-key"
@@ -47,6 +53,10 @@ func newFakeIssuer(t *testing.T) *fakeIssuer {
 
 	mux := http.NewServeMux()
 	mux.HandleFunc("/.well-known/openid-configuration", func(w http.ResponseWriter, _ *http.Request) {
+		if f.discoveryHits.Add(1) <= f.unavailableFor {
+			http.Error(w, "no available server", http.StatusServiceUnavailable)
+			return
+		}
 		writeJSON(t, w, map[string]any{
 			"issuer":                                f.server.URL,
 			"authorization_endpoint":                f.server.URL + "/authorize",