Adding lint github action

.github/workflows/ci.yml

@@ -22,6 +22,21 @@ jobs:
     - name: Test
       run: make test
 
+  lint:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.14.x
+      - uses: actions/checkout@v2
+      - name: Install golangci-lint
+        run: |
+          curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.38.0
+          golangci-lint --version
+      - name: Lint
+        run: make lint
+
 
   generated-files-integrity:
     runs-on: ubuntu-20.04

code/go/0chain.net/blobbercore/allocation/allocationchange.go

@@ -169,5 +169,4 @@ func (a *AllocationChangeCollector) DeleteChanges(ctx context.Context) {
 			logging.Logger.Error("AllocationChangeProcessor_DeleteTempFile", zap.Error(err))
 		}
 	}
-	return
 }

code/go/0chain.net/blobbercore/handler/grpcMiddleware.go

@@ -45,7 +45,9 @@ func unaryDatabaseTransactionInjector() grpc.UnaryServerInterceptor {
 func unaryTimeoutInterceptor() grpc.UnaryServerInterceptor {
 	return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
 		deadline := time.Now().Add(time.Duration(TIMEOUT_SECONDS * time.Second))
-		ctx, _ = context.WithDeadline(ctx, deadline)
+		ctx, canceler := context.WithDeadline(ctx, deadline)
+		defer canceler()
+
 		return handler(ctx, req)
 	}
 }

code/go/0chain.net/blobbercore/handler/handler.go

@@ -3,17 +3,18 @@
 package handler
 
 import (
-	"0chain.net/blobbercore/config"
-	"0chain.net/blobbercore/constants"
-	"0chain.net/blobbercore/datastore"
-	"0chain.net/blobbercore/stats"
-	"0chain.net/core/common"
 	"context"
 	"net/http"
 	"os"
 	"runtime/pprof"
 	"time"
 
+	"0chain.net/blobbercore/config"
+	"0chain.net/blobbercore/constants"
+	"0chain.net/blobbercore/datastore"
+	"0chain.net/blobbercore/stats"
+	"0chain.net/core/common"
+
 	. "0chain.net/core/logging"
 	"go.uber.org/zap"
 
@@ -204,7 +205,9 @@ func CommitHandler(ctx context.Context, r *http.Request) (interface{}, error) {
 }
 
 func ReferencePathHandler(ctx context.Context, r *http.Request) (interface{}, error) {
-	ctx, _ = context.WithTimeout(ctx, time.Second*10)
+	ctx, canceler := context.WithTimeout(ctx, time.Second*10)
+	defer canceler()
+
 	ctx = setupHandlerContext(ctx, r)
 
 	response, err := storageHandler.GetReferencePath(ctx, r)

code/go/0chain.net/blobbercore/handler/helper.go

@@ -30,7 +30,7 @@ func RegisterGRPCServices(r *mux.Router, server *grpc.Server) {
 	blobberService := newGRPCBlobberService(&storageHandler, packHandler)
 	mux := runtime.NewServeMux()
 	blobbergrpc.RegisterBlobberServer(server, blobberService)
-	blobbergrpc.RegisterBlobberHandlerServer(context.Background(), mux, blobberService)
+	_ = blobbergrpc.RegisterBlobberHandlerServer(context.Background(), mux, blobberService)
 	r.PathPrefix("/").Handler(mux)
 }
 

code/go/0chain.net/blobbercore/handler/storage_handler.go

@@ -1,14 +1,15 @@
 package handler
 
 import (
-	"0chain.net/core/encryption"
 	"context"
 	"encoding/json"
-	"github.com/gorilla/mux"
 	"net/http"
 	"strconv"
 	"strings"
 
+	"0chain.net/core/encryption"
+	"github.com/gorilla/mux"
+
 	"0chain.net/blobbercore/stats"
 	"go.uber.org/zap"
 
@@ -537,7 +538,6 @@ func (fsh *StorageHandler) getReferencePath(ctx context.Context, r *http.Request
 	}
 
 	resCh <- &refPathResult
-	return
 }
 
 func (fsh *StorageHandler) GetObjectPath(ctx context.Context, r *http.Request) (*ObjectPathResult, error) {

code/go/0chain.net/blobbercore/util/json.go

@@ -2,9 +2,8 @@ package util
 
 import (
 	"fmt"
-	"strings"
 	"reflect"
-	"errors"
+	"strings"
 )
 
 // Validate unmarshalled data with tag-based rules
@@ -20,7 +19,7 @@ func UnmarshalValidation(v interface{}) error {
 		if strings.Contains(validation, "required") && fields.Field(i).IsZero() {
 			// todo: better try this first:
 			// jsonFieldName := fields.Type().Field(i).Tag.Get("json")
-			return errors.New(fmt.Sprintf("The '%s' field is required", fields.Type().Field(i).Name))
+			return fmt.Errorf("The '%s' field is required", fields.Type().Field(i).Name)
 		}
 	}