github.com/afking/bazel-gazelle@v0.0.0-20180301150245-c02bc0f529e8/internal/packages/fileinfo_proto.go (about) 1 /* Copyright 2017 The Bazel Authors. All rights reserved. 2 3 Licensed under the Apache License, Version 2.0 (the "License"); 4 you may not use this file except in compliance with the License. 5 You may obtain a copy of the License at 6 7 http://www.apache.org/licenses/LICENSE-2.0 8 9 Unless required by applicable law or agreed to in writing, software 10 distributed under the License is distributed on an "AS IS" BASIS, 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 See the License for the specific language governing permissions and 13 limitations under the License. 14 */ 15 16 package packages 17 18 import ( 19 "bytes" 20 "io/ioutil" 21 "log" 22 "path" 23 "regexp" 24 "sort" 25 "strconv" 26 "strings" 27 "unicode" 28 29 "github.com/bazelbuild/bazel-gazelle/internal/config" 30 ) 31 32 var protoRe = buildProtoRegexp() 33 34 const ( 35 importSubexpIndex = 1 36 packageSubexpIndex = 2 37 goPackageSubexpIndex = 3 38 serviceSubexpIndex = 4 39 ) 40 41 func protoFileInfo(c *config.Config, dir, rel, name string) fileInfo { 42 info := fileNameInfo(dir, rel, name) 43 content, err := ioutil.ReadFile(info.path) 44 if err != nil { 45 log.Printf("%s: error reading proto file: %v", info.path, err) 46 return info 47 } 48 49 for _, match := range protoRe.FindAllSubmatch(content, -1) { 50 switch { 51 case match[importSubexpIndex] != nil: 52 imp := unquoteProtoString(match[importSubexpIndex]) 53 info.imports = append(info.imports, imp) 54 55 case match[packageSubexpIndex] != nil: 56 pkg := string(match[packageSubexpIndex]) 57 if info.packageName == "" { 58 info.packageName = strings.Replace(pkg, ".", "_", -1) 59 } 60 61 case match[goPackageSubexpIndex] != nil: 62 gopkg := unquoteProtoString(match[goPackageSubexpIndex]) 63 // If there's no / in the package option, then it's just a 64 // simple package name, not a full import path. 65 if strings.LastIndexByte(gopkg, '/') == -1 { 66 info.packageName = gopkg 67 } else { 68 if i := strings.LastIndexByte(gopkg, ';'); i != -1 { 69 info.importPath = gopkg[:i] 70 info.packageName = gopkg[i+1:] 71 } else { 72 info.importPath = gopkg 73 info.packageName = path.Base(gopkg) 74 } 75 } 76 77 case match[serviceSubexpIndex] != nil: 78 info.hasServices = true 79 80 default: 81 // Comment matched. Nothing to extract. 82 } 83 } 84 sort.Strings(info.imports) 85 86 if info.packageName == "" { 87 stem := strings.TrimSuffix(name, ".proto") 88 fs := strings.FieldsFunc(stem, func(r rune) bool { 89 return !(unicode.IsLetter(r) || unicode.IsNumber(r) || r == '_') 90 }) 91 info.packageName = strings.Join(fs, "_") 92 } 93 94 return info 95 } 96 97 // Based on https://developers.google.com/protocol-buffers/docs/reference/proto3-spec 98 func buildProtoRegexp() *regexp.Regexp { 99 hexEscape := `\\[xX][0-9a-fA-f]{2}` 100 octEscape := `\\[0-7]{3}` 101 charEscape := `\\[abfnrtv'"\\]` 102 charValue := strings.Join([]string{hexEscape, octEscape, charEscape, "[^\x00\\'\\\"\\\\]"}, "|") 103 strLit := `'(?:` + charValue + `|")*'|"(?:` + charValue + `|')*"` 104 ident := `[A-Za-z][A-Za-z0-9_]*` 105 fullIdent := ident + `(?:\.` + ident + `)*` 106 importStmt := `\bimport\s*(?:public|weak)?\s*(?P<import>` + strLit + `)\s*;` 107 packageStmt := `\bpackage\s*(?P<package>` + fullIdent + `)\s*;` 108 goPackageStmt := `\boption\s*go_package\s*=\s*(?P<go_package>` + strLit + `)\s*;` 109 serviceStmt := `(?P<service>service)` 110 comment := `//[^\n]*` 111 protoReSrc := strings.Join([]string{importStmt, packageStmt, goPackageStmt, serviceStmt, comment}, "|") 112 return regexp.MustCompile(protoReSrc) 113 } 114 115 func unquoteProtoString(q []byte) string { 116 // Adjust quotes so that Unquote is happy. We need a double quoted string 117 // without unescaped double quote characters inside. 118 noQuotes := bytes.Split(q[1:len(q)-1], []byte{'"'}) 119 if len(noQuotes) != 1 { 120 for i := 0; i < len(noQuotes)-1; i++ { 121 if len(noQuotes[i]) == 0 || noQuotes[i][len(noQuotes[i])-1] != '\\' { 122 noQuotes[i] = append(noQuotes[i], '\\') 123 } 124 } 125 q = append([]byte{'"'}, bytes.Join(noQuotes, []byte{'"'})...) 126 q = append(q, '"') 127 } 128 if q[0] == '\'' { 129 q[0] = '"' 130 q[len(q)-1] = '"' 131 } 132 133 s, err := strconv.Unquote(string(q)) 134 if err != nil { 135 log.Panicf("unquoting string literal %s from proto: %v", q, err) 136 } 137 return s 138 }