Add Github workflows for unit tests, go tidiness and code linters (#3)

The static code checkers revealed a lot of issues, some of them quite
"interesting". I fixed them, even though there is still room for
improvement in terms of code quality.

Signed-off-by: Antonin Bas <[email protected]>

.github/workflows/go.yml

@@ -0,0 +1,44 @@
+name: Go
+on:
+  pull_request:
+    branches:
+    - main
+  push:
+    branches:
+    - main
+
+jobs:
+  test:
+    runs-on: [ubuntu-latest]
+    steps:
+    - name: Set up Go 1.15
+      uses: actions/setup-go@v1
+      with:
+        go-version: 1.15
+    - name: Check-out code
+      uses: actions/checkout@v2
+    - name: Run unit tests
+      run: |
+        make test
+
+  tidy:
+    runs-on: [ubuntu-latest]
+    steps:
+    - name: Set up Go 1.15
+      uses: actions/setup-go@v1
+      with:
+        go-version: 1.15
+    - name: Check-out code
+      uses: actions/checkout@v2
+    - name: Check tidiness
+      run: |
+        ./ci/check-tidy.sh
+
+  golangci:
+    runs-on: [ubuntu-latest]
+    steps:
+    - name: Check-out code
+      uses: actions/checkout@v2
+    - name: Run code linters
+      run: |
+        make golangci

.gitignore

@@ -0,0 +1,13 @@
+.cache
+.golangci-bin
+
+.DS_Store
+
+# VIM
+.*.swp
+
+# Emacs
+*~
+
+.idea/
+.vscode/

.golangci.yml

@@ -0,0 +1,24 @@
+run:
+  tests: true
+  timeout: 5m
+  skip-files:
+    - ".*\\.pb\\.go"
+  skip-dirs-use-default: true
+
+linters-settings:
+  goimports:
+    local-prefixes: antrea-io/libOpenflow
+
+linters:
+  disable-all: true
+  enable: # see https://golangci-lint.run/usage/linters/
+    - deadcode
+    - staticcheck
+    - govet
+    - gofmt
+    - goimports
+    - gosec
+    - misspell
+
+run:
+  deadline: 5m

Makefile

@@ -0,0 +1,22 @@
+GO                 ?= go
+
+all: test
+
+.PHONY: test
+test:
+	$(GO) test -v ./...
+
+# code linting
+.golangci-bin:
+	@echo "===> Installing Golangci-lint <==="
+	@curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $@ v1.41.1
+
+.PHONY: golangci
+golangci: .golangci-bin
+	@echo "===> Running golangci <==="
+	@GOOS=linux .golangci-bin/golangci-lint run -c .golangci.yml
+
+.PHONY: golangci-fix
+golangci-fix: .golangci-bin
+	@echo "===> Running golangci-fix <==="
+	@GOOS=linux .golangci-bin/golangci-lint run -c .golangci.yml --fix

ci/check-tidy.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+set -e
+
+: "${GO:=go}"
+
+goversion=$($GO version)
+
+$GO mod tidy
+
+rc=0
+diff=$(git diff --exit-code -- go.mod go.sum) || rc=$?
+
+if [ $rc -ne 0 ]; then
+    echo "Found some differences when running 'go mod tidy'"
+    echo "**********"
+    echo "$diff"
+    echo "**********"
+    echo "Please ensure you are using the correct version of go ($goversion), run 'go mod tidy', and commit the changes"
+fi
+
+exit $rc

common/header.go

@@ -64,7 +64,7 @@ func (h *Header) UnmarshalBinary(data []byte) error {
 }
 
 const (
-	reserved = iota
+	reserved = iota //nolint:deadcode
 	HelloElemType_VersionBitmap
 )
 
@@ -136,10 +136,12 @@ func (h *HelloElemVersionBitmap) Len() (n uint16) {
 
 func (h *HelloElemVersionBitmap) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(h.Len()))
-	bytes := make([]byte, 0)
+	var bytes []byte
 	next := 0
 
-	bytes, err = h.HelloElemHeader.MarshalBinary()
+	if bytes, err = h.HelloElemHeader.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[next:], bytes)
 	next += len(bytes)
 
@@ -202,11 +204,13 @@ func (h *Hello) Len() (n uint16) {
 
 func (h *Hello) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(h.Len()))
-	bytes := make([]byte, 0)
+	var bytes []byte
 	next := 0
 
 	h.Header.Length = h.Len()
-	bytes, err = h.Header.MarshalBinary()
+	if bytes, err = h.Header.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[next:], bytes)
 	next += len(bytes)
 

openflow13/action.go

@@ -154,10 +154,12 @@ func (a *ActionOutput) Len() (n uint16) {
 
 func (a *ActionOutput) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(a.Len()))
-	b := make([]byte, 0)
+	var b []byte
 	n := 0
 
-	b, err = a.ActionHeader.MarshalBinary()
+	if b, err = a.ActionHeader.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[n:], b)
 	n += len(b)
 	binary.BigEndian.PutUint32(data[n:], a.Port)
@@ -243,10 +245,12 @@ func (a *ActionGroup) Len() (n uint16) {
 
 func (a *ActionGroup) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(a.Len()))
-	b := make([]byte, 0)
+	var b []byte
 	n := 0
 
-	b, err = a.ActionHeader.MarshalBinary()
+	if b, err = a.ActionHeader.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[n:], b)
 	n += len(b)
 	binary.BigEndian.PutUint32(data[n:], a.GroupId)
@@ -447,22 +451,31 @@ func (a *ActionSetField) Len() (n uint16) {
 
 func (a *ActionSetField) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(a.Len()))
+	var b []byte
 	n := 0
-	b, err := a.ActionHeader.MarshalBinary()
+	if b, err = a.ActionHeader.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data, b)
 	n += int(a.ActionHeader.Len())
 
-	b, err = a.Field.MarshalBinary()
+	if b, err = a.Field.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[n:], b)
 
 	return
 }
 func (a *ActionSetField) UnmarshalBinary(data []byte) error {
 	n := 0
-	err := a.ActionHeader.UnmarshalBinary(data[n:])
+	if err := a.ActionHeader.UnmarshalBinary(data[n:]); err != nil {
+		return err
+	}
 	n += int(a.ActionHeader.Len())
-	err = a.Field.UnmarshalBinary(data[n:])
+	if err := a.Field.UnmarshalBinary(data[n:]); err != nil {
+		return err
+	}
 	n += int(a.Field.Len())
 
-	return err
+	return nil
 }

openflow13/bundles.go

@@ -263,9 +263,12 @@ func (e *VendorError) Len() uint16 {
 
 func (e *VendorError) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(e.Len()))
+	var headerBytes []byte
 	n := 0
 
-	headerBytes, err := e.Header.MarshalBinary()
+	if headerBytes, err = e.Header.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[n:], headerBytes)
 	n += len(headerBytes)
 	binary.BigEndian.PutUint16(data[n:], e.Type)
@@ -274,7 +277,9 @@ func (e *VendorError) MarshalBinary() (data []byte, err error) {
 	n += 2
 	binary.BigEndian.PutUint32(data[n:], e.ExperimenterID)
 	n += 4
-	headerBytes, err = e.Data.MarshalBinary()
+	if headerBytes, err = e.Data.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[n:], headerBytes)
 	n += len(headerBytes)
 	return

openflow13/flowmod.go

@@ -3,8 +3,9 @@ package openflow13
 import (
 	"encoding/binary"
 
-	"antrea-io/libOpenflow/common"
 	log "github.com/sirupsen/logrus"
+
+	"antrea-io/libOpenflow/common"
 )
 
 // ofp_flow_mod     1.3
@@ -76,7 +77,9 @@ func (f *FlowMod) Len() (n uint16) {
 
 func (f *FlowMod) MarshalBinary() (data []byte, err error) {
 	f.Header.Length = f.Len()
-	data, err = f.Header.MarshalBinary()
+	if data, err = f.Header.MarshalBinary(); err != nil {
+		return
+	}
 
 	bytes := make([]byte, 40)
 	n := 0
@@ -105,11 +108,15 @@ func (f *FlowMod) MarshalBinary() (data []byte, err error) {
 	n += 2 // for pad
 	data = append(data, bytes...)
 
-	bytes, err = f.Match.MarshalBinary()
+	if bytes, err = f.Match.MarshalBinary(); err != nil {
+		return
+	}
 	data = append(data, bytes...)
 
 	for _, instr := range f.Instructions {
-		bytes, err = instr.MarshalBinary()
+		if bytes, err = instr.MarshalBinary(); err != nil {
+			return
+		}
 		data = append(data, bytes...)
 		log.Debugf("flowmod instr: %v", bytes)
 	}
@@ -212,9 +219,12 @@ func (f *FlowRemoved) Len() (n uint16) {
 
 func (f *FlowRemoved) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(f.Len()))
+	var bytes []byte
 	next := 0
 
-	bytes, err := f.Header.MarshalBinary()
+	if bytes, err = f.Header.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[next:], bytes)
 	next += int(f.Header.Len())
 
@@ -241,16 +251,19 @@ func (f *FlowRemoved) MarshalBinary() (data []byte, err error) {
 	binary.BigEndian.PutUint64(data[next:], f.ByteCount)
 	next += 8
 
-	bytes, err = f.Match.MarshalBinary()
+	if bytes, err = f.Match.MarshalBinary(); err != nil {
+		return
+	}
 	copy(data[next:], bytes)
 	next += int(f.Match.Len())
 	return
 }
 
 func (f *FlowRemoved) UnmarshalBinary(data []byte) error {
 	next := 0
-	var err error
-	err = f.Header.UnmarshalBinary(data[next:])
+	if err := f.Header.UnmarshalBinary(data[next:]); err != nil {
+		return err
+	}
 	next += int(f.Header.Len())
 
 	f.Cookie = binary.BigEndian.Uint64(data[next:])
@@ -274,10 +287,12 @@ func (f *FlowRemoved) UnmarshalBinary(data []byte) error {
 	f.ByteCount = binary.BigEndian.Uint64(data[next:])
 	next += 8
 
-	err = f.Match.UnmarshalBinary(data[next:])
+	if err := f.Match.UnmarshalBinary(data[next:]); err != nil {
+		return err
+	}
 	next += int(f.Match.Len())
 
-	return err
+	return nil
 }
 
 // ofp_flow_removed_reason 1.3

openflow13/group.go

@@ -5,8 +5,9 @@ package openflow13
 import (
 	"encoding/binary"
 
-	"antrea-io/libOpenflow/common"
 	log "github.com/sirupsen/logrus"
+
+	"antrea-io/libOpenflow/common"
 )
 
 const (