fix: use errcheck exclusions instead of noisy suppressions

Configure golangci-lint to exclude errcheck for idiomatic Go patterns
where errors are unactionable (ResponseWriter.Write, fmt.Fprint,
json.Encode, Flush, Close in test files). Revert _, _ = suppressions
back to clean idiomatic Go.

Author: ravisuhag

.golangci.yml

@@ -14,6 +14,17 @@ linters:
     - unused
     - whitespace
     - misspell
+  exclusions:
+    rules:
+      # Don't require error checks on HTTP response writes, fmt prints,
+      # JSON encoding, buffer flushes, and response body closes — these
+      # are idiomatic Go patterns where errors are unactionable.
+      - linters: [errcheck]
+        path: '.*\.go'
+        text: '(ResponseWriter|Fprint|Fprintln|Fprintf|Encode|\.Flush|\.Close|\.Start)\b'
+    # Don't lint test helpers for errcheck in test files
+      - linters: [errcheck]
+        path: '_test\.go'
 linters-settings:
   revive:
     ignore-generated-header: true

app/app_test.go

@@ -59,7 +59,7 @@ func TestAppStartAndShutdown(t *testing.T) {
 
 		resp, err := http.Get("http://127.0.0.1:18950/ping")
 		require.NoError(t, err)
-		defer func() { _ = resp.Body.Close() }()
+		defer resp.Body.Close()
 		assert.Equal(t, http.StatusOK, resp.StatusCode)
 
 		cancel()
@@ -124,19 +124,19 @@ func TestAppStartAndShutdown(t *testing.T) {
 			app.WithLogger(logger.NewNoop()),
 			app.WithAddr("127.0.0.1:18953"),
 			app.WithHandler("/hello", http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-				_, _ = fmt.Fprint(w, "world")
+				fmt.Fprint(w, "world")
 			})),
 			app.WithHealthCheck("/ping"),
 			app.WithH2C(),
 		)
 		require.NoError(t, err)
 
-		go func() { _ = a.Start(ctx) }()
+		go a.Start(ctx)
 		time.Sleep(100 * time.Millisecond)
 
 		resp, err := http.Get("http://127.0.0.1:18953/hello")
 		require.NoError(t, err)
-		defer func() { _ = resp.Body.Close() }()
+		defer resp.Body.Close()
 
 		body, _ := io.ReadAll(resp.Body)
 		assert.Equal(t, "world", string(body))

logger/logrus_test.go

@@ -22,7 +22,7 @@ func TestLogrus(t *testing.T) {
 			DisableTimestamp: true,
 		}))
 		logger.Info("hello world")
-		_ = foo.Flush()
+		foo.Flush()
 
 		assert.Equal(t, "level=info msg=\"hello world\"\n", b.String())
 	})
@@ -34,7 +34,7 @@ func TestLogrus(t *testing.T) {
 			DisableTimestamp: true,
 		}))
 		logger.Debug("hello world")
-		_ = foo.Flush()
+		foo.Flush()
 
 		assert.Equal(t, "", b.String())
 	})
@@ -46,7 +46,7 @@ func TestLogrus(t *testing.T) {
 			DisableTimestamp: true,
 		}))
 		logger.Debug("current values", "day", 11, "month", "aug")
-		_ = foo.Flush()
+		foo.Flush()
 
 		assert.Equal(t, "level=debug msg=\"current values\" day=11 month=aug\n", b.String())
 	})
@@ -59,7 +59,7 @@ func TestLogrus(t *testing.T) {
 		}))
 		var err = fmt.Errorf("request failed")
 		logger.Error(err.Error(), "hello", "world")
-		_ = foo.Flush()
+		foo.Flush()
 		assert.Equal(t, "level=error msg=\"request failed\" hello=world\n", b.String())
 	})
 	t.Run("should ignore params if malformed", func(t *testing.T) {
@@ -71,7 +71,7 @@ func TestLogrus(t *testing.T) {
 		}))
 		var err = fmt.Errorf("request failed")
 		logger.Error(err.Error(), "hello", "world", "!")
-		_ = foo.Flush()
+		foo.Flush()
 		assert.Equal(t, "level=error msg=\"request failed\"\n", b.String())
 	})
 }

logger/zap_test.go

@@ -66,7 +66,7 @@ func TestZap(t *testing.T) {
 
 		zapper := logger.NewZap(buildBufferedZapOption(bWriter, mockedTime, randomString(10)))
 		zapper.Info("hello", "wor", "ld")
-		_ = bWriter.Flush()
+		bWriter.Flush()
 
 		assert.Equal(t, mockedTime.Format("2006-01-02T15:04:05.000Z0700")+"\tINFO\thello\t{\"wor\": \"ld\"}\n", b.String())
 	})
@@ -79,7 +79,7 @@ func TestZap(t *testing.T) {
 		ctx := zapper.NewContext(context.Background())
 		contextualLog := logger.ZapFromContext(ctx)
 		contextualLog.Info("hello", "wor", "ld")
-		_ = bWriter.Flush()
+		bWriter.Flush()
 
 		assert.Equal(t, mockedTime.Format("2006-01-02T15:04:05.000Z0700")+"\tINFO\thello\t{\"wor\": \"ld\"}\n", b.String())
 	})
@@ -93,7 +93,7 @@ func TestZap(t *testing.T) {
 		ctx = logger.ZapContextWithFields(ctx, zap.Int("one", 1))
 		ctx = logger.ZapContextWithFields(ctx, zap.String("two", "two"))
 		logger.ZapFromContext(ctx).Info("hello", "wor", "ld")
-		_ = bWriter.Flush()
+		bWriter.Flush()
 
 		assert.Equal(t, mockedTime.Format("2006-01-02T15:04:05.000Z0700")+"\tINFO\thello\t{\"one\": 1, \"two\": \"two\", \"wor\": \"ld\"}\n", b.String())
 	})

middleware/middleware_test.go

@@ -78,7 +78,7 @@ func TestRequestIDHTTP(t *testing.T) {
 	chain := middleware.DefaultHTTP(logger.NewNoop())
 	handler := chain(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		id := requestid.FromContext(r.Context())
-		_, _ = w.Write([]byte(id))
+		w.Write([]byte(id))
 	}))
 
 	t.Run("generates ID when missing", func(t *testing.T) {

server/server.go

@@ -95,5 +95,5 @@ func (s *Server) Start(ctx context.Context) error {
 func healthHandler(w http.ResponseWriter, _ *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
-	_ = json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
+	json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
 }

server/server_test.go

@@ -36,7 +36,7 @@ func TestServer(t *testing.T) {
 			cancel()
 			t.Skip("cannot determine random port from outside; covered by other tests")
 		}
-		defer func() { _ = resp.Body.Close() }()
+		defer resp.Body.Close()
 
 		assert.Equal(t, http.StatusOK, resp.StatusCode)
 		cancel()
@@ -48,7 +48,7 @@ func TestServer(t *testing.T) {
 
 		handler := http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 			w.WriteHeader(http.StatusOK)
-			_, _ = fmt.Fprint(w, "hello")
+			fmt.Fprint(w, "hello")
 		})
 
 		srv := server.New(
@@ -100,12 +100,12 @@ func TestServer(t *testing.T) {
 			server.WithHealthCheck("/healthz"),
 		)
 
-		go func() { _ = srv.Start(ctx) }()
+		go srv.Start(ctx)
 		time.Sleep(100 * time.Millisecond)
 
 		resp, err := http.Get("http://127.0.0.1:18923/healthz")
 		require.NoError(t, err)
-		defer func() { _ = resp.Body.Close() }()
+		defer resp.Body.Close()
 
 		assert.Equal(t, http.StatusOK, resp.StatusCode)
 		assert.Equal(t, "application/json", resp.Header.Get("Content-Type"))
@@ -129,12 +129,12 @@ func TestServer(t *testing.T) {
 			server.WithHealthCheck("/ping"),
 		)
 
-		go func() { _ = srv.Start(ctx) }()
+		go srv.Start(ctx)
 		time.Sleep(100 * time.Millisecond)
 
 		resp, err := http.Get("http://127.0.0.1:18924/ping")
 		require.NoError(t, err)
-		defer func() { _ = resp.Body.Close() }()
+		defer resp.Body.Close()
 
 		assert.Equal(t, http.StatusOK, resp.StatusCode)