Update golangci-lint to v2.12.2 with canonical config (#187)

Bumps golangci-lint from v2.10.1 to v2.12.2 everywhere it is pinned and installs the canonical `.golangci.yml`, then fixes every finding the new linter surfaces so `make check` is green.

## Version pins

- `Dockerfile` lint stage: `golangci/golangci-lint:v2.12.2` (Debian-based), tag plus digest pin
- `script/bootstrap`: `GOLANGCI_LINT_VERSION=2.12.2` with updated `linux-amd64`/`linux-arm64` release-archive sha256 pins

## Config

`.golangci.yml` replaced with the canonical config. Material change: the old file declared `version: "2"` but kept settings under the legacy top-level `linters-settings` key, which golangci-lint v2 ignores — so the intended thresholds (`lll` 88, `funlen` 80/50, `cyclop` 15, `dupl` 100) were not being applied. The canonical file moves them under `linters.settings` and drops `issues.exclude-use-default`.

## Lint fixes (216 findings)

- `lll` (96): wrapped lines to the 88-column limit
- `noctx` (46): `httptest.NewRequestWithContext` with `t.Context()` throughout the tests
- `goconst` (24): shared constants for template/JSON keys in `internal/handlers` and repeated test literals
- `gosec` (23): app-page redirects now go through a `redirectToApp` helper that path-escapes the app ID (G710 open redirect); `http.ServeFile` of the internally derived deployment log path annotated like the adjacent `os.Stat` (G703)
- `dupl` (22): extracted a generic `findAllByAppID` in `internal/models`, a `deleteAppResource` helper in `internal/handlers`, a shared `parsePush` in `internal/service/webhook`, and table-driven/helper-based dedup in tests
- `nolintlint` (5): removed `//nolint:funlen` directives made obsolete by the new limits (plus one more that became obsolete after refactoring)
- `nilerr` (3, surfaced during fixing): resource-delete lookups now propagate the find error to the caller

No behavior changes intended; all tests pass and `make check` is green.

Note: golangci-lint v2.12 warns that `gomodguard` is deprecated in favor of `gomodguard_v2` — a future canonical-config update should address this centrally.
Co-authored-by: sneak <sneak@sneak.berlin>
Reviewed-on: #187
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

internal/middleware/cors_test.go

@@ -24,21 +24,30 @@ func newCORSTestMiddleware(corsOrigins string) *Middleware {
 	}
 }
 
-func TestCORS_NoOriginsConfigured_NoCORSHeaders(t *testing.T) {
-	t.Parallel()
+// assertNoCORSHeaders runs a request with the given Origin header through
+// CORS middleware configured with corsOrigins and asserts that no
+// Access-Control-Allow-Origin header is set.
+func assertNoCORSHeaders(t *testing.T, corsOrigins, origin, msg string) {
+	t.Helper()
 
-	m := newCORSTestMiddleware("")
+	m := newCORSTestMiddleware(corsOrigins)
 	handler := m.CORS()(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 		w.WriteHeader(http.StatusOK)
 	}))
 
-	req := httptest.NewRequest(http.MethodGet, "/", nil)
-	req.Header.Set("Origin", "https://evil.com")
+	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
+	req.Header.Set("Origin", origin)
 
 	rec := httptest.NewRecorder()
 	handler.ServeHTTP(rec, req)
 
-	assert.Empty(t, rec.Header().Get("Access-Control-Allow-Origin"),
+	assert.Empty(t, rec.Header().Get("Access-Control-Allow-Origin"), msg)
+}
+
+func TestCORS_NoOriginsConfigured_NoCORSHeaders(t *testing.T) {
+	t.Parallel()
+
+	assertNoCORSHeaders(t, "", "https://evil.com",
 		"expected no CORS headers when no origins configured")
 }
 
@@ -50,7 +59,7 @@ func TestCORS_OriginsConfigured_AllowsMatchingOrigin(t *testing.T) {
 		w.WriteHeader(http.StatusOK)
 	}))
 
-	req := httptest.NewRequest(http.MethodGet, "/", nil)
+	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
 	req.Header.Set("Origin", "https://app.example.com")
 
 	rec := httptest.NewRecorder()
@@ -65,17 +74,6 @@ func TestCORS_OriginsConfigured_AllowsMatchingOrigin(t *testing.T) {
 func TestCORS_OriginsConfigured_RejectsNonMatchingOrigin(t *testing.T) {
 	t.Parallel()
 
-	m := newCORSTestMiddleware("https://app.example.com")
-	handler := m.CORS()(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-		w.WriteHeader(http.StatusOK)
-	}))
-
-	req := httptest.NewRequest(http.MethodGet, "/", nil)
-	req.Header.Set("Origin", "https://evil.com")
-
-	rec := httptest.NewRecorder()
-	handler.ServeHTTP(rec, req)
-
-	assert.Empty(t, rec.Header().Get("Access-Control-Allow-Origin"),
+	assertNoCORSHeaders(t, "https://app.example.com", "https://evil.com",
 		"expected no CORS headers for non-matching origin")
 }

internal/middleware/middleware.go

@@ -370,8 +370,9 @@ func (m *Middleware) LoginRateLimit() func(http.Handler) http.Handler {
 	}
 }
 
-// APISessionAuth returns middleware that requires session authentication for API routes.
-// Unlike SessionAuth, it returns JSON 401 responses instead of redirecting to /login.
+// APISessionAuth returns middleware that requires session authentication
+// for API routes. Unlike SessionAuth, it returns JSON 401 responses instead
+// of redirecting to /login.
 func (m *Middleware) APISessionAuth() func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(

internal/middleware/ratelimit_test.go

@@ -30,13 +30,15 @@ func TestLoginRateLimitAllowsUpToBurst(t *testing.T) {
 
 	mw := newTestMiddleware(t)
 
-	handler := mw.LoginRateLimit()(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-		w.WriteHeader(http.StatusOK)
-	}))
+	handler := mw.LoginRateLimit()(http.HandlerFunc(
+		func(w http.ResponseWriter, _ *http.Request) {
+			w.WriteHeader(http.StatusOK)
+		},
+	))
 
 	// First 5 requests should succeed (burst)
 	for i := range 5 {
-		req := httptest.NewRequest(http.MethodPost, "/login", nil)
+		req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
 		req.RemoteAddr = "192.168.1.1:12345"
 		rec := httptest.NewRecorder()
 		handler.ServeHTTP(rec, req)
@@ -44,11 +46,12 @@ func TestLoginRateLimitAllowsUpToBurst(t *testing.T) {
 	}
 
 	// 6th request should be rate limited
-	req := httptest.NewRequest(http.MethodPost, "/login", nil)
+	req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
 	req.RemoteAddr = "192.168.1.1:12345"
 	rec := httptest.NewRecorder()
 	handler.ServeHTTP(rec, req)
-	assert.Equal(t, http.StatusTooManyRequests, rec.Code, "6th request should be rate limited")
+	assert.Equal(t, http.StatusTooManyRequests, rec.Code,
+		"6th request should be rate limited")
 }
 
 //nolint:paralleltest // mutates global loginLimiter
@@ -57,27 +60,29 @@ func TestLoginRateLimitIsolatesIPs(t *testing.T) {
 
 	mw := newTestMiddleware(t)
 
-	handler := mw.LoginRateLimit()(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-		w.WriteHeader(http.StatusOK)
-	}))
+	handler := mw.LoginRateLimit()(http.HandlerFunc(
+		func(w http.ResponseWriter, _ *http.Request) {
+			w.WriteHeader(http.StatusOK)
+		},
+	))
 
 	// Exhaust IP1's budget
 	for range 5 {
-		req := httptest.NewRequest(http.MethodPost, "/login", nil)
-		req.RemoteAddr = "10.0.0.1:1234"
+		req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
+		req.RemoteAddr = testProxyAddr
 		rec := httptest.NewRecorder()
 		handler.ServeHTTP(rec, req)
 	}
 
 	// IP1 should be blocked
-	req := httptest.NewRequest(http.MethodPost, "/login", nil)
-	req.RemoteAddr = "10.0.0.1:1234"
+	req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
+	req.RemoteAddr = testProxyAddr
 	rec := httptest.NewRecorder()
 	handler.ServeHTTP(rec, req)
 	assert.Equal(t, http.StatusTooManyRequests, rec.Code)
 
 	// IP2 should still work
-	req2 := httptest.NewRequest(http.MethodPost, "/login", nil)
+	req2 := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
 	req2.RemoteAddr = "10.0.0.2:1234"
 	rec2 := httptest.NewRecorder()
 	handler.ServeHTTP(rec2, req2)
@@ -90,25 +95,28 @@ func TestLoginRateLimitReturns429Body(t *testing.T) {
 
 	mw := newTestMiddleware(t)
 
-	handler := mw.LoginRateLimit()(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-		w.WriteHeader(http.StatusOK)
-	}))
+	handler := mw.LoginRateLimit()(http.HandlerFunc(
+		func(w http.ResponseWriter, _ *http.Request) {
+			w.WriteHeader(http.StatusOK)
+		},
+	))
 
 	// Exhaust burst
 	for range 5 {
-		req := httptest.NewRequest(http.MethodPost, "/login", nil)
+		req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
 		req.RemoteAddr = "172.16.0.1:5555"
 		rec := httptest.NewRecorder()
 		handler.ServeHTTP(rec, req)
 	}
 
-	req := httptest.NewRequest(http.MethodPost, "/login", nil)
+	req := httptest.NewRequestWithContext(t.Context(), http.MethodPost, "/login", nil)
 	req.RemoteAddr = "172.16.0.1:5555"
 	rec := httptest.NewRecorder()
 	handler.ServeHTTP(rec, req)
 	assert.Equal(t, http.StatusTooManyRequests, rec.Code)
 	assert.Contains(t, rec.Body.String(), "Too Many Requests")
-	assert.NotEmpty(t, rec.Header().Get("Retry-After"), "should include Retry-After header")
+	assert.NotEmpty(t, rec.Header().Get("Retry-After"),
+		"should include Retry-After header")
 }
 
 func TestIPLimiterEvictsStaleEntries(t *testing.T) {

internal/middleware/realip_test.go

@@ -7,6 +7,16 @@ import (
 	"testing"
 )
 
+// Shared test addresses (also used by ratelimit_test.go).
+const (
+	testProxyAddr   = "10.0.0.1:1234"
+	testRealIP      = "203.0.113.5"
+	testXFFIP       = "198.51.100.1"
+	testPrivateIP   = "192.168.1.1"
+	testPublicIP    = "93.184.216.34"
+	testPublicDNSIP = "8.8.8.8"
+)
+
 func TestRealIP(t *testing.T) { //nolint:funlen // table-driven test
 	t.Parallel()
 
@@ -20,63 +30,63 @@ func TestRealIP(t *testing.T) { //nolint:funlen // table-driven test
 		// === Trusted proxy (RFC1918 / loopback) — headers ARE honoured ===
 		{
 			name:       "trusted: X-Real-IP from 10.x",
-			remoteAddr: "10.0.0.1:1234",
-			xRealIP:    "203.0.113.5",
+			remoteAddr: testProxyAddr,
+			xRealIP:    testRealIP,
 			xff:        "198.51.100.1, 10.0.0.1",
-			want:       "203.0.113.5",
+			want:       testRealIP,
 		},
 		{
 			name:       "trusted: XFF from 10.x when no X-Real-IP",
-			remoteAddr: "10.0.0.1:1234",
+			remoteAddr: testProxyAddr,
 			xff:        "198.51.100.1, 10.0.0.1",
-			want:       "198.51.100.1",
+			want:       testXFFIP,
 		},
 		{
 			name:       "trusted: XFF single IP from 10.x",
-			remoteAddr: "10.0.0.1:1234",
+			remoteAddr: testProxyAddr,
 			xff:        "203.0.113.10",
 			want:       "203.0.113.10",
 		},
 		{
 			name:       "trusted: falls back to RemoteAddr (192.168.x)",
 			remoteAddr: "192.168.1.1:5678",
-			want:       "192.168.1.1",
+			want:       testPrivateIP,
 		},
 		{
 			name:       "trusted: RemoteAddr without port",
-			remoteAddr: "192.168.1.1",
-			want:       "192.168.1.1",
+			remoteAddr: testPrivateIP,
+			want:       testPrivateIP,
 		},
 		{
 			name:       "trusted: X-Real-IP with whitespace from 10.x",
-			remoteAddr: "10.0.0.1:1234",
+			remoteAddr: testProxyAddr,
 			xRealIP:    "  203.0.113.5  ",
-			want:       "203.0.113.5",
+			want:       testRealIP,
 		},
 		{
 			name:       "trusted: XFF with whitespace from 10.x",
-			remoteAddr: "10.0.0.1:1234",
+			remoteAddr: testProxyAddr,
 			xff:        "  198.51.100.1 , 10.0.0.1",
-			want:       "198.51.100.1",
+			want:       testXFFIP,
 		},
 		{
 			name:       "trusted: empty X-Real-IP falls through to XFF from 10.x",
-			remoteAddr: "10.0.0.1:1234",
+			remoteAddr: testProxyAddr,
 			xRealIP:    "  ",
-			xff:        "198.51.100.1",
-			want:       "198.51.100.1",
+			xff:        testXFFIP,
+			want:       testXFFIP,
 		},
 		{
 			name:       "trusted: loopback honours X-Real-IP",
 			remoteAddr: "127.0.0.1:9999",
-			xRealIP:    "93.184.216.34",
-			want:       "93.184.216.34",
+			xRealIP:    testPublicIP,
+			want:       testPublicIP,
 		},
 		{
 			name:       "trusted: 172.16.x honours XFF",
 			remoteAddr: "172.16.0.1:4321",
-			xff:        "8.8.8.8",
-			want:       "8.8.8.8",
+			xff:        testPublicDNSIP,
+			want:       testPublicDNSIP,
 		},
 
 		// === Untrusted proxy (public IP) — headers IGNORED, use RemoteAddr ===
@@ -97,17 +107,17 @@ func TestRealIP(t *testing.T) { //nolint:funlen // table-driven test
 			remoteAddr: "8.8.8.8:443",
 			xRealIP:    "1.2.3.4",
 			xff:        "5.6.7.8",
-			want:       "8.8.8.8",
+			want:       testPublicDNSIP,
 		},
 		{
 			name:       "untrusted: no headers, public RemoteAddr",
 			remoteAddr: "93.184.216.34:8080",
-			want:       "93.184.216.34",
+			want:       testPublicIP,
 		},
 		{
 			name:       "untrusted: public RemoteAddr without port",
-			remoteAddr: "93.184.216.34",
-			want:       "93.184.216.34",
+			remoteAddr: testPublicIP,
+			want:       testPublicIP,
 		},
 	}
 
@@ -139,7 +149,9 @@ func TestIsTrustedProxy(t *testing.T) {
 
 	trusted := []string{"10.0.0.1", "10.255.255.255", "172.16.0.1", "172.31.255.255",
 		"192.168.0.1", "192.168.255.255", "127.0.0.1", "127.255.255.255", "::1"}
-	untrusted := []string{"8.8.8.8", "203.0.113.1", "172.32.0.1", "11.0.0.1", "2001:db8::1"}
+	untrusted := []string{
+		testPublicDNSIP, "203.0.113.1", "172.32.0.1", "11.0.0.1", "2001:db8::1",
+	}
 
 	for _, addr := range trusted {
 		ip := net.ParseIP(addr)