Setup gometalinter + fix lint

.travis.yml

@@ -4,9 +4,12 @@ install:
 - go get github.com/Masterminds/glide
 - wget https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/.travis/install-protoc.sh && chmod +x install-protoc.sh && ./install-protoc.sh 3.2.0
 - go get -u github.com/golang/protobuf/protoc-gen-go
+- go get -u github.com/alecthomas/gometalinter
+- gometalinter --install
 script:
 - make install
 - make test
+- make lint
 cache:
   directories:
   - $HOME/local

Makefile

@@ -29,3 +29,7 @@ docker.build:
 .PHONY: docker.push
 docker.push: docker.build
 	docker push moul/protoc-gen-gotemplate
+
+.PHONY: lint
+lint:
+	gometalinter --disable-all --enable=errcheck --enable=vet --enable=vetshadow --enable=golint --enable=gas --enable=ineffassign --enable=goconst --enable=goimports --enable=gofmt --exclude="Binds to all network interfaces" --exclude="should have comment" --enable=staticcheck --enable=gosimple --enable=misspell --deadline=120s . ./cmd/... ./helpers/...

cmd/web-editor/main.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"net/http"
 	"os"
 	"os/exec"
@@ -32,18 +33,23 @@ func generate(w http.ResponseWriter, r *http.Request) {
 	if err != nil {
 		returnError(w, err)
 	}
-	defer os.RemoveAll(dir) // clean up
-	if err := ioutil.WriteFile(filepath.Join(dir, "example.proto"), []byte(input.Protobuf), 0644); err != nil {
+	// clean up
+	defer func() {
+		if err = os.RemoveAll(dir); err != nil {
+			log.Printf("error: failed to remove temporary directory: %v", err)
+		}
+	}()
+	if err = ioutil.WriteFile(filepath.Join(dir, "example.proto"), []byte(input.Protobuf), 0644); err != nil {
 		returnError(w, err)
 		return
 	}
-	if err := ioutil.WriteFile(filepath.Join(dir, "example.output.tmpl"), []byte(input.Template), 0644); err != nil {
+	if err = ioutil.WriteFile(filepath.Join(dir, "example.output.tmpl"), []byte(input.Template), 0644); err != nil {
 		returnError(w, err)
 		return
 	}
 
 	// generate
-	cmd := exec.Command("protoc", "-I"+dir, "--gotemplate_out=template_dir="+dir+",debug=true:"+dir, filepath.Join(dir, "example.proto"))
+	cmd := exec.Command("protoc", "-I"+dir, "--gotemplate_out=template_dir="+dir+",debug=true:"+dir, filepath.Join(dir, "example.proto")) // #nosec
 	out, err := cmd.CombinedOutput()
 	if err != nil {
 		returnError(w, errors.New(string(out)))
@@ -64,20 +70,32 @@ func returnContent(w http.ResponseWriter, output interface{}) {
 	payload := map[string]interface{}{
 		"output": fmt.Sprintf("%s", output),
 	}
-	response, _ := json.Marshal(payload)
+	response, err := json.Marshal(payload)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
-	w.Write(response)
+	if _, err := w.Write(response); err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
 }
 
 func returnError(w http.ResponseWriter, err error) {
 	payload := map[string]interface{}{
 		"error": fmt.Sprintf("%v", err),
 	}
-	response, _ := json.Marshal(payload)
+	response, err := json.Marshal(payload)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusInternalServerError)
-	w.Write(response)
+	if _, err := w.Write(response); err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
 }
 
 func main() {
@@ -94,5 +112,7 @@ func main() {
 	h := handlers.LoggingHandler(os.Stderr, r)
 	h = handlers.CompressHandler(h)
 	h = handlers.RecoveryHandler()(h)
-	http.ListenAndServe(addr, r)
+	if err := http.ListenAndServe(addr, h); err != nil {
+		panic(err)
+	}
 }

encoder.go

@@ -100,11 +100,20 @@ func (e *GenericTemplateBasedEncoder) templates() ([]string, error) {
 
 func (e *GenericTemplateBasedEncoder) genAst(templateFilename string) (*Ast, error) {
 	// prepare the ast passed to the template engine
-	hostname, _ := os.Hostname()
-	pwd, _ := os.Getwd()
+	hostname, err := os.Hostname()
+	if err != nil {
+		return nil, err
+	}
+	pwd, err := os.Getwd()
+	if err != nil {
+		return nil, err
+	}
 	goPwd := ""
 	if os.Getenv("GOPATH") != "" {
-		goPwd, _ = filepath.Rel(os.Getenv("GOPATH")+"/src", pwd)
+		goPwd, err = filepath.Rel(os.Getenv("GOPATH")+"/src", pwd)
+		if err != nil {
+			return nil, err
+		}
 		if strings.Contains(goPwd, "../") {
 			goPwd = ""
 		}
@@ -170,7 +179,8 @@ func (e *GenericTemplateBasedEncoder) Files() []*plugin_go.CodeGeneratorResponse
 	resultChan := make(chan *plugin_go.CodeGeneratorResponse_File, length)
 	for _, templateFilename := range templates {
 		go func(tmpl string) {
-			content, translatedFilename, err := e.buildContent(tmpl)
+			var translatedFilename, content string
+			content, translatedFilename, err = e.buildContent(tmpl)
 			if err != nil {
 				errChan <- err
 				return

helpers/helpers.go

@@ -15,7 +15,7 @@ import (
 	options "google.golang.org/genproto/googleapis/api/annotations"
 )
 
-var jsReservedRe *regexp.Regexp = regexp.MustCompile(`(^|[^A-Za-z])(do|if|in|for|let|new|try|var|case|else|enum|eval|false|null|this|true|void|with|break|catch|class|const|super|throw|while|yield|delete|export|import|public|return|static|switch|typeof|default|extends|finally|package|private|continue|debugger|function|arguments|interface|protected|implements|instanceof)($|[^A-Za-z])`)
+var jsReservedRe = regexp.MustCompile(`(^|[^A-Za-z])(do|if|in|for|let|new|try|var|case|else|enum|eval|false|null|this|true|void|with|break|catch|class|const|super|throw|while|yield|delete|export|import|public|return|static|switch|typeof|default|extends|finally|package|private|continue|debugger|function|arguments|interface|protected|implements|instanceof)($|[^A-Za-z])`)
 
 var (
 	registry *ggdescriptor.Registry // some helpers need access to registry
@@ -32,11 +32,17 @@ var ProtoHelpersFuncMap = template.FuncMap{
 		return i.String()
 	},
 	"json": func(v interface{}) string {
-		a, _ := json.Marshal(v)
+		a, err := json.Marshal(v)
+		if err != nil {
+			return err.Error()
+		}
 		return string(a)
 	},
 	"prettyjson": func(v interface{}) string {
-		a, _ := json.MarshalIndent(v, "", "  ")
+		a, err := json.MarshalIndent(v, "", "  ")
+		if err != nil {
+			return err.Error()
+		}
 		return string(a)
 	},
 	"splitArray": func(sep string, s string) []interface{} {
@@ -315,7 +321,7 @@ func goType(pkg string, f *descriptor.FieldDescriptorProto) string {
 
 func jsType(f *descriptor.FieldDescriptorProto) string {
 	template := "%s"
-	if isFieldRepeated(f) == true {
+	if isFieldRepeated(f) {
 		template = "Array<%s>"
 	}
 

main.go

@@ -18,6 +18,11 @@ var (
 	registry *ggdescriptor.Registry // some helpers need access to registry
 )
 
+const (
+	boolTrue  = "true"
+	boolFalse = "false"
+)
+
 func main() {
 	g := generator.New()
 
@@ -26,7 +31,7 @@ func main() {
 		g.Error(err, "reading input")
 	}
 
-	if err := proto.Unmarshal(data, g.Request); err != nil {
+	if err = proto.Unmarshal(data, g.Request); err != nil {
 		g.Error(err, "parsing input proto")
 	}
 
@@ -54,37 +59,32 @@ func main() {
 			switch parts[0] {
 			case "template_dir":
 				templateDir = parts[1]
-				break
 			case "destination_dir":
 				destinationDir = parts[1]
-				break
 			case "single-package-mode":
 				switch strings.ToLower(parts[1]) {
-				case "true", "t":
+				case boolTrue, "t":
 					singlePackageMode = true
-				case "false", "f":
+				case boolFalse, "f":
 				default:
 					log.Printf("Err: invalid value for single-package-mode: %q", parts[1])
 				}
-				break
 			case "debug":
 				switch strings.ToLower(parts[1]) {
-				case "true", "t":
+				case boolTrue, "t":
 					debug = true
-				case "false", "f":
+				case boolFalse, "f":
 				default:
 					log.Printf("Err: invalid value for debug: %q", parts[1])
 				}
-				break
 			case "all":
 				switch strings.ToLower(parts[1]) {
-				case "true", "t":
+				case boolTrue, "t":
 					all = true
-				case "false", "f":
+				case boolFalse, "f":
 				default:
 					log.Printf("Err: invalid value for debug: %q", parts[1])
 				}
-				break
 			default:
 				log.Printf("Err: unknown parameter: %q", param)
 			}
@@ -104,7 +104,7 @@ func main() {
 	if singlePackageMode {
 		registry = ggdescriptor.NewRegistry()
 		pgghelpers.SetRegistry(registry)
-		if err := registry.Load(g.Request); err != nil {
+		if err = registry.Load(g.Request); err != nil {
 			g.Error(err, "registry: failed to load the request")
 		}
 	}
@@ -113,7 +113,7 @@ func main() {
 	for _, file := range g.Request.GetProtoFile() {
 		if all {
 			if singlePackageMode {
-				if _, err := registry.LookupFile(file.GetName()); err != nil {
+				if _, err = registry.LookupFile(file.GetName()); err != nil {
 					g.Error(err, "registry: failed to lookup file %q", file.GetName())
 				}
 			}