chore: Remove revive:unhandled-error - errcheck is more flexible (i…

…nfluxdata#13008)

.golangci.yml

@@ -76,6 +76,13 @@ linters-settings:
       - "**/testutil/**"
       - "**/tools/**"
       - "**/*_test.go"
+  errcheck:
+    # List of functions to exclude from checking, where each entry is a single function to exclude.
+    # See https://github.com/kisielk/errcheck#excluding-functions for details.
+    exclude-functions:
+      - "(*hash/maphash.Hash).Write"
+      - "(*hash/maphash.Hash).WriteByte"
+      - "(*hash/maphash.Hash).WriteString"
   gosec:
     # To select a subset of rules to run.
     # Available rules: https://github.com/securego/gosec#available-rules
@@ -153,8 +160,6 @@ linters-settings:
       - name: time-naming
       - name: unconditional-recursion
       - name: unexported-naming
-      - name: unhandled-error
-        arguments: [ "fmt.Printf", "fmt.Println", "fmt.Print", "fmt.Fprintf", "fmt.Fprint", "fmt.Fprintln" ]
       - name: unnecessary-stmt
       - name: unreachable-code
       - name: unused-parameter
@@ -213,7 +218,6 @@ issues:
     - don't use an underscore in package name
     # EXC0001 errcheck: Almost all programs ignore errors on these functions and in most cases it's ok
     - Error return value of .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*print(f|ln)?|os\.(Un)?Setenv). is not checked
-    - Unhandled error in call to function ((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*print(f|ln)?|os\.(Un)?Setenv)
     # EXC0013 revive: Annoying issue about not having a comment. The rare codebase has such comments
     - package comment should be of the form "(.+)...
     # EXC0015 revive: Annoying issue about not having a comment. The rare codebase has such comments

metric/metric.go

@@ -262,13 +262,13 @@ func (m *metric) Copy() telegraf.Metric {
 
 func (m *metric) HashID() uint64 {
 	h := fnv.New64a()
-	h.Write([]byte(m.name)) //nolint:revive // all Write() methods for hash in fnv.go returns nil err
-	h.Write([]byte("\n"))   //nolint:revive // all Write() methods for hash in fnv.go returns nil err
+	h.Write([]byte(m.name))
+	h.Write([]byte("\n"))
 	for _, tag := range m.tags {
-		h.Write([]byte(tag.Key))   //nolint:revive // all Write() methods for hash in fnv.go returns nil err
-		h.Write([]byte("\n"))      //nolint:revive // all Write() methods for hash in fnv.go returns nil err
-		h.Write([]byte(tag.Value)) //nolint:revive // all Write() methods for hash in fnv.go returns nil err
-		h.Write([]byte("\n"))      //nolint:revive // all Write() methods for hash in fnv.go returns nil err
+		h.Write([]byte(tag.Key))
+		h.Write([]byte("\n"))
+		h.Write([]byte(tag.Value))
+		h.Write([]byte("\n"))
 	}
 	return h.Sum64()
 }

metric/series_grouper.go

@@ -87,20 +87,20 @@ func groupID(seed maphash.Seed, measurement string, taglist []*telegraf.Tag, tm
 	var mh maphash.Hash
 	mh.SetSeed(seed)
 
-	mh.WriteString(measurement) //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
-	mh.WriteByte(0)             //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
+	mh.WriteString(measurement)
+	mh.WriteByte(0)
 
 	for _, tag := range taglist {
-		mh.WriteString(tag.Key)   //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
-		mh.WriteByte(0)           //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
-		mh.WriteString(tag.Value) //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
-		mh.WriteByte(0)           //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
+		mh.WriteString(tag.Key)
+		mh.WriteByte(0)
+		mh.WriteString(tag.Value)
+		mh.WriteByte(0)
 	}
-	mh.WriteByte(0) //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
+	mh.WriteByte(0)
 
 	var tsBuf [8]byte
 	binary.BigEndian.PutUint64(tsBuf[:], uint64(tm.UnixNano()))
-	mh.Write(tsBuf[:]) //nolint:errcheck,revive // all Write***() methods for hash in maphash.go returns nil err
+	mh.Write(tsBuf[:])
 
 	return mh.Sum64()
 }

models/running_output_test.go

@@ -40,7 +40,7 @@ func BenchmarkRunningOutputAddWrite(b *testing.B) {
 
 	for n := 0; n < b.N; n++ {
 		ro.AddMetric(testutil.TestMetric(101, "metric1"))
-		ro.Write() //nolint: errcheck,revive // skip checking err for benchmark tests
+		ro.Write() //nolint: errcheck // skip checking err for benchmark tests
 	}
 }
 
@@ -56,7 +56,7 @@ func BenchmarkRunningOutputAddWriteEvery100(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		ro.AddMetric(testutil.TestMetric(101, "metric1"))
 		if n%100 == 0 {
-			ro.Write() //nolint: errcheck,revive // skip checking err for benchmark tests
+			ro.Write() //nolint: errcheck // skip checking err for benchmark tests
 		}
 	}
 }

plugins/common/opcua/input/input_client.go

@@ -198,11 +198,11 @@ func newMP(n *NodeMetricMapping) metricParts {
 	var sb strings.Builder
 	for i, key := range keys {
 		if i != 0 {
-			sb.WriteString(", ") //nolint:revive // writes to a string-builder will always succeed
+			sb.WriteString(", ")
 		}
-		sb.WriteString(key)               //nolint:revive // writes to a string-builder will always succeed
-		sb.WriteString("=")               //nolint:revive // writes to a string-builder will always succeed
-		sb.WriteString(n.MetricTags[key]) //nolint:revive // writes to a string-builder will always succeed
+		sb.WriteString(key)
+		sb.WriteString("=")
+		sb.WriteString(n.MetricTags[key])
 	}
 	x := metricParts{
 		metricName: n.metricName,

plugins/common/starlark/field_dict.go

@@ -19,17 +19,17 @@ type FieldDict struct {
 
 func (d FieldDict) String() string {
 	buf := new(strings.Builder)
-	buf.WriteString("{") //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+	buf.WriteString("{")
 	sep := ""
 	for _, item := range d.Items() {
 		k, v := item[0], item[1]
-		buf.WriteString(sep)        //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(k.String()) //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(": ")       //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(v.String()) //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+		buf.WriteString(sep)
+		buf.WriteString(k.String())
+		buf.WriteString(": ")
+		buf.WriteString(v.String())
 		sep = ", "
 	}
-	buf.WriteString("}") //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+	buf.WriteString("}")
 	return buf.String()
 }
 

plugins/common/starlark/metric.go

@@ -37,15 +37,15 @@ func (m *Metric) Unwrap() telegraf.Metric {
 // it behaves more like the repr function would in Python.
 func (m *Metric) String() string {
 	buf := new(strings.Builder)
-	buf.WriteString("Metric(")           //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(m.Name().String())   //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(", tags=")           //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(m.Tags().String())   //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(", fields=")         //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(m.Fields().String()) //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(", time=")           //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(m.Time().String())   //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-	buf.WriteString(")")                 //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+	buf.WriteString("Metric(")
+	buf.WriteString(m.Name().String())
+	buf.WriteString(", tags=")
+	buf.WriteString(m.Tags().String())
+	buf.WriteString(", fields=")
+	buf.WriteString(m.Fields().String())
+	buf.WriteString(", time=")
+	buf.WriteString(m.Time().String())
+	buf.WriteString(")")
 	return buf.String()
 }
 

plugins/common/starlark/tag_dict.go

@@ -18,17 +18,17 @@ type TagDict struct {
 
 func (d TagDict) String() string {
 	buf := new(strings.Builder)
-	buf.WriteString("{") //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+	buf.WriteString("{")
 	sep := ""
 	for _, item := range d.Items() {
 		k, v := item[0], item[1]
-		buf.WriteString(sep)        //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(k.String()) //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(": ")       //nolint:revive // from builder.go: "It returns the length of r and a nil error."
-		buf.WriteString(v.String()) //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+		buf.WriteString(sep)
+		buf.WriteString(k.String())
+		buf.WriteString(": ")
+		buf.WriteString(v.String())
 		sep = ", "
 	}
-	buf.WriteString("}") //nolint:revive // from builder.go: "It returns the length of r and a nil error."
+	buf.WriteString("}")
 	return buf.String()
 }
 

plugins/inputs/burrow/burrow_test.go

@@ -37,7 +37,7 @@ func getHTTPServer() *httptest.Server {
 		body, code := getResponseJSON(r.RequestURI)
 		w.WriteHeader(code)
 		w.Header().Set("Content-Type", "application/json")
-		w.Write(body) //nolint:errcheck,revive // ignore the returned error as the test will fail anyway
+		w.Write(body) //nolint:errcheck // ignore the returned error as the test will fail anyway
 	}))
 }
 
@@ -61,7 +61,7 @@ func getHTTPServerBasicAuth() *httptest.Server {
 		body, code := getResponseJSON(r.RequestURI)
 		w.WriteHeader(code)
 		w.Header().Set("Content-Type", "application/json")
-		w.Write(body) //nolint:errcheck,revive // ignore the returned error as the test will fail anyway
+		w.Write(body) //nolint:errcheck // ignore the returned error as the test will fail anyway
 	}))
 }
 

plugins/inputs/ceph/ceph.go

@@ -222,9 +222,9 @@ func (m *metric) name() string {
 	buf := bytes.Buffer{}
 	for i := len(m.pathStack) - 1; i >= 0; i-- {
 		if buf.Len() > 0 {
-			buf.WriteString(".") //nolint:revive // should never return an error
+			buf.WriteString(".")
 		}
-		buf.WriteString(m.pathStack[i]) //nolint:revive // should never return an error
+		buf.WriteString(m.pathStack[i])
 	}
 	return buf.String()
 }

plugins/inputs/cloud_pubsub_push/cloud_pubsub_push.go

@@ -136,8 +136,7 @@ func (p *PubSubPush) Start(acc telegraf.Accumulator) error {
 // Stop cleans up all resources
 func (p *PubSubPush) Stop() {
 	p.cancel()
-	//nolint:errcheck,revive // we cannot do anything if the shutdown fails
-	p.server.Shutdown(p.ctx)
+	p.server.Shutdown(p.ctx) //nolint:errcheck // we cannot do anything if the shutdown fails
 	p.wg.Wait()
 }
 

plugins/inputs/diskio/diskio_linux.go

@@ -83,10 +83,10 @@ func (d *DiskIO) diskInfo(devName string) (map[string]string, error) {
 		}
 		if l[:2] == "S:" {
 			if devlinks.Len() > 0 {
-				devlinks.WriteString(" ") //nolint:revive // this will never fail
+				devlinks.WriteString(" ")
 			}
-			devlinks.WriteString("/dev/") //nolint:revive // this will never fail
-			devlinks.WriteString(l[2:])   //nolint:revive // this will never fail
+			devlinks.WriteString("/dev/")
+			devlinks.WriteString(l[2:])
 			continue
 		}
 		if l[:2] != "E:" {

plugins/inputs/exec/exec.go

@@ -111,7 +111,7 @@ func (c CommandRunner) truncate(buf bytes.Buffer) bytes.Buffer {
 		buf.Truncate(i)
 	}
 	if didTruncate {
-		buf.WriteString("...") //nolint:revive // will always return nil or panic
+		buf.WriteString("...")
 	}
 	return buf
 }

plugins/inputs/haproxy/haproxy_test.go

@@ -34,8 +34,7 @@ func (s statServer) serverSocket(l net.Listener) {
 
 			data := buf[:n]
 			if string(data) == "show stat\n" {
-				//nolint:errcheck,revive // we return anyway
-				c.Write(csvOutputSample)
+				c.Write(csvOutputSample) //nolint:errcheck // we return anyway
 			}
 		}(conn)
 	}

plugins/inputs/http_response/http_response_test.go

@@ -99,7 +99,7 @@ func setUpTestMux() http.Handler {
 		fmt.Fprintf(w, "hit the good page!")
 	})
 	mux.HandleFunc("/invalidUTF8", func(w http.ResponseWriter, req *http.Request) {
-		w.Write([]byte{0xff, 0xfe, 0xfd}) //nolint:errcheck,revive // ignore the returned error as the test will fail anyway
+		w.Write([]byte{0xff, 0xfe, 0xfd}) //nolint:errcheck // ignore the returned error as the test will fail anyway
 	})
 	mux.HandleFunc("/noheader", func(w http.ResponseWriter, req *http.Request) {
 		fmt.Fprintf(w, "hit the good page!")

plugins/inputs/jenkins/jenkins_test.go

@@ -98,7 +98,7 @@ func (h mockHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	w.Write(b) //nolint:errcheck,revive // ignore the returned error as the tests will fail anyway
+	w.Write(b) //nolint:errcheck // ignore the returned error as the tests will fail anyway
 }
 
 func TestGatherNodeData(t *testing.T) {

plugins/inputs/mesos/mesos_test.go

@@ -288,15 +288,15 @@ func TestMain(m *testing.M) {
 	masterRouter.HandleFunc("/metrics/snapshot", func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(masterMetrics) //nolint:errcheck,revive // ignore the returned error as we cannot do anything about it anyway
+		json.NewEncoder(w).Encode(masterMetrics) //nolint:errcheck // ignore the returned error as we cannot do anything about it anyway
 	})
 	masterTestServer = httptest.NewServer(masterRouter)
 
 	slaveRouter := http.NewServeMux()
 	slaveRouter.HandleFunc("/metrics/snapshot", func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(slaveMetrics) //nolint:errcheck,revive // ignore the returned error as we cannot do anything about it anyway
+		json.NewEncoder(w).Encode(slaveMetrics) //nolint:errcheck // ignore the returned error as we cannot do anything about it anyway
 	})
 	slaveTestServer = httptest.NewServer(slaveRouter)
 

plugins/inputs/phpfpm/child.go

@@ -291,7 +291,7 @@ func (c *child) serveRequest(req *request, body io.ReadCloser) {
 	// some sort of abort request to the host, so the host
 	// can properly cut off the client sending all the data.
 	// For now just bound it a little and
-	io.CopyN(io.Discard, body, 100<<20) //nolint:errcheck,revive // ignore the returned error as we cannot do anything about it anyway
+	io.CopyN(io.Discard, body, 100<<20) //nolint:errcheck // ignore the returned error as we cannot do anything about it anyway
 	body.Close()
 
 	if !req.keepConn {

plugins/inputs/powerdns/powerdns_linux_test.go

@@ -28,7 +28,7 @@ func (s statServer) serverSocket(l net.Listener) {
 
 			data := buf[:n]
 			if string(data) == "show * \n" {
-				c.Write([]byte(metrics)) //nolint:errcheck,revive // ignore the returned error as we need to close the socket anyway
+				c.Write([]byte(metrics)) //nolint:errcheck // ignore the returned error as we need to close the socket anyway
 				c.Close()
 			}
 		}(conn)

plugins/inputs/powerdns_recursor/powerdns_recursor_test.go

@@ -127,7 +127,7 @@ func TestV1PowerdnsRecursorGeneratesMetrics(t *testing.T) {
 
 			data := buf[:n]
 			if string(data) == "get-all\n" {
-				socket.WriteToUnix([]byte(metrics), remote) //nolint:errcheck,revive // ignore the returned error as we need to close the socket anyway
+				socket.WriteToUnix([]byte(metrics), remote) //nolint:errcheck // ignore the returned error as we need to close the socket anyway
 				socket.Close()
 			}
 
@@ -189,8 +189,8 @@ func TestV2PowerdnsRecursorGeneratesMetrics(t *testing.T) {
 
 			data := buf[:n]
 			if string(data) == "get-all" {
-				socket.WriteToUnix([]byte{0, 0, 0, 0}, remote) //nolint:errcheck,revive // ignore the returned error as we need to close the socket anyway
-				socket.WriteToUnix([]byte(metrics), remote)    //nolint:errcheck,revive // ignore the returned error as we need to close the socket anyway
+				socket.WriteToUnix([]byte{0, 0, 0, 0}, remote) //nolint:errcheck // ignore the returned error as we need to close the socket anyway
+				socket.WriteToUnix([]byte(metrics), remote)    //nolint:errcheck // ignore the returned error as we need to close the socket anyway
 				socket.Close()
 			}
 
@@ -258,10 +258,10 @@ func TestV3PowerdnsRecursorGeneratesMetrics(t *testing.T) {
 			}
 
 			if string(buf) == "get-all" {
-				conn.Write([]byte{0, 0, 0, 0}) //nolint:errcheck,revive // ignore the returned error as we need to close the socket anyway
+				conn.Write([]byte{0, 0, 0, 0}) //nolint:errcheck // ignore the returned error as we need to close the socket anyway
 				metrics := []byte(metrics)
-				writeNativeUIntToConn(conn, uint(len(metrics))) //nolint:errcheck,revive // ignore the returned error as we cannot do anything about it anyway
-				conn.Write(metrics)                             //nolint:errcheck,revive // ignore the returned error as we cannot do anything about it anyway
+				writeNativeUIntToConn(conn, uint(len(metrics))) //nolint:errcheck // ignore the returned error as we cannot do anything about it anyway
+				conn.Write(metrics)                             //nolint:errcheck // ignore the returned error as we cannot do anything about it anyway
 				socket.Close()
 			}
 

plugins/inputs/statsd/statsd.go

@@ -900,8 +900,8 @@ func (s *Statsd) handler(conn *net.TCPConn, id string) {
 
 			b := s.bufPool.Get().(*bytes.Buffer)
 			b.Reset()
-			b.Write(scanner.Bytes()) //nolint:revive // Writes to a bytes buffer always succeed, so do not check the errors here
-			b.WriteByte('\n')        //nolint:revive // Writes to a bytes buffer always succeed, so do not check the errors here
+			b.Write(scanner.Bytes())
+			b.WriteByte('\n')
 
 			select {
 			case s.in <- input{Buffer: b, Time: time.Now(), Addr: remoteIP}:

plugins/inputs/zipkin/zipkin.go

@@ -120,7 +120,7 @@ func (z *Zipkin) Stop() {
 	defer z.waitGroup.Wait()
 	defer cancel()
 
-	z.server.Shutdown(ctx) //nolint:errcheck,revive // Ignore the returned error as we cannot do anything about it anyway
+	z.server.Shutdown(ctx) //nolint:errcheck // Ignore the returned error as we cannot do anything about it anyway
 }
 
 // Listen creates an http server on the zipkin instance it is called with, and