Merge pull request #623 from TheThingsNetwork/feature/headers-check

Use config file for headers check

.mage/header.yml

@@ -0,0 +1,21 @@
+rules:
+- include: [.go,.js,.make,Makefile,.styl,.proto]
+  exclude: [.snap,.json,.goreleaser.yml]
+  header:
+    |
+    Copyright © 2019 The Things Network Foundation, The Things Industries B.V.
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+  prefix: '// '
+- include: [.make,Makefile]
+  prefix: '# '

.mage/headers.go

@@ -16,63 +16,89 @@ package ttnmage
 
 import (
 	"bufio"
+	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 
 	"github.com/magefile/mage/mg"
+	"gopkg.in/yaml.v2"
 )
 
 // Headers namespace.
 type Headers mg.Namespace
 
-var fileCommentPrefix = map[string]string{
-	".go":    "// ",
-	".js":    "// ",
-	".make":  "# ",
-	".styl":  "// ",
-	".proto": "// ",
+// HeaderRule in the header config file.
+type HeaderRule struct {
+	Include     []string `yaml:"include"`
+	Exclude     []string `yaml:"exclude"`
+	Header      string   `yaml:"header"`
+	headerLines [][]byte
+	Prefix      string `yaml:"prefix"`
 }
 
-type fileFilter struct {
-	exclude []string
-	include []string
+func (r *HeaderRule) split() {
+	r.headerLines = bytes.Split([]byte(strings.TrimSpace(r.Header)), []byte("\n"))
 }
 
-func (f fileFilter) match(search string) (match bool) {
-	if len(f.include) > 0 {
-		for _, item := range f.include {
-			if strings.Contains(search, item) {
+func (r *HeaderRule) match(path string) (match bool) {
+	if len(r.Include) > 0 {
+		for _, item := range r.Include {
+			if strings.Contains(path, item) {
 				match = true
 			}
 		}
 	} else {
 		match = true
 	}
-	for _, item := range f.exclude {
-		if strings.Contains(search, item) {
+	for _, item := range r.Exclude {
+		if strings.Contains(path, item) {
 			return false
 		}
 	}
 	return
 }
 
+// HeaderConfig is the format of the header configuration file.
+type HeaderConfig struct {
+	Rules []*HeaderRule `yaml:"rules"`
+}
+
+func (c *HeaderConfig) split() {
+	for _, rule := range c.Rules {
+		rule.split()
+	}
+}
+
+func (c *HeaderConfig) get(filename string) (r *HeaderRule) {
+	for _, rule := range c.Rules {
+		if !rule.match(filename) {
+			continue
+		}
+		if r == nil {
+			r = &HeaderRule{}
+		}
+		if rule.Header != "" {
+			r.Header, r.headerLines = rule.Header, rule.headerLines
+		}
+		if rule.Prefix != "" {
+			r.Prefix = rule.Prefix
+		}
+	}
+	return r
+}
+
 var (
-	headerFilter fileFilter
 	headerFile   string
-	headerLines  []string
+	headerConfig HeaderConfig
 )
 
 func init() {
-	headerFilter = fileFilter{
-		exclude: strings.Fields(os.Getenv("HEADER_EXCLUDE")),
-		include: strings.Fields(os.Getenv("HEADER_INCLUDE")),
-	}
 	headerFile = os.Getenv("HEADER_FILE")
 	if headerFile == "" {
-		headerFile = ".mage/header.txt"
+		headerFile = ".mage/header.yml"
 	}
 }
 
@@ -81,7 +107,10 @@ func (Headers) loadFile() error {
 	if err != nil {
 		return err
 	}
-	headerLines = strings.Split(strings.TrimSpace(string(headerBytes)), "\n")
+	if err = yaml.Unmarshal(headerBytes, &headerConfig); err != nil {
+		return err
+	}
+	headerConfig.split()
 	return nil
 }
 
@@ -94,27 +123,30 @@ func (err checkErr) Error() string {
 	return fmt.Sprintf("%s %s", err.Path, err.Reason)
 }
 
-func (h Headers) check(path, commentPrefix string) error {
+func (h Headers) check(path string) error {
+	rule := headerConfig.get(path)
+	if rule == nil {
+		return nil
+	}
 	f, err := os.Open(path)
 	if err != nil {
 		return err
 	}
 	defer f.Close()
 	s := bufio.NewScanner(f)
-	for i, expected := range headerLines {
-		expected = strings.TrimSpace(commentPrefix + expected)
+	for i, expected := range rule.headerLines {
 		if !s.Scan() {
 			return &checkErr{Path: path, Reason: "has less lines than expected header"}
 		}
-		line := s.Text()
-		if i == 0 && strings.Contains(line, "generated") {
+		line := s.Bytes()
+		if i == 0 && bytes.Contains(line, []byte("generated")) {
 			return nil // Skip generated files.
 		}
-		if s.Text() != expected {
-			return &checkErr{Path: path, Reason: fmt.Sprintf("did not contain expected line: %s", expected)}
+		if !bytes.Equal(bytes.TrimPrefix(line, []byte(rule.Prefix)), expected) && !bytes.Equal(line, bytes.TrimSpace([]byte(rule.Prefix))) {
+			return &checkErr{Path: path, Reason: fmt.Sprintf("did not contain expected header line: %s", string(expected))}
 		}
 	}
-	if s.Scan() && s.Text() != "" {
+	if s.Scan() && len(s.Bytes()) != 0 {
 		return &checkErr{Path: path, Reason: "does not have empty line after header"}
 	}
 	return nil
@@ -153,13 +185,8 @@ func (h Headers) Check() error {
 		if selectedFiles != nil && !selectedFiles[path] {
 			return nil
 		}
-		if !headerFilter.match(path) {
-			return nil
-		}
-		if prefix, ok := fileCommentPrefix[filepath.Ext(path)]; ok {
-			if checkErr := h.check(path, prefix); checkErr != nil {
-				checkErrs = append(checkErrs, checkErr)
-			}
+		if checkErr := h.check(path); checkErr != nil {
+			checkErrs = append(checkErrs, checkErr)
 		}
 		return nil
 	})