| // Copyright 2012 Aryan Naraghi ([email protected]) |
| // |
| // 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. |
| |
| // A demo for difflib. This program accepts the paths to two files and |
| // launches a web server at port 8080 that serves the diff results. |
| package main |
| |
| import ( |
| "fmt" |
| "github.com/aryann/difflib" |
| "html" |
| "html/template" |
| "io/ioutil" |
| "net/http" |
| "os" |
| "strings" |
| ) |
| |
| var hostPort = "localhost:8080" |
| |
| var templateString = ` |
| <!doctype html> |
| <html> |
| <head> |
| <meta charset="utf-8" /> |
| <title>difflib results</title> |
| <style type="text/css"> |
| table { |
| background-color: lightgrey; |
| border-spacing: 1px; |
| } |
| |
| tr { |
| background-color: white; |
| border-bottom: 1px solid black; |
| } |
| |
| .line-num { |
| width: 50px; |
| } |
| |
| .added { |
| background-color: green; |
| } |
| |
| .deleted { |
| background-color: red; |
| } |
| </style> |
| </head> |
| <body> |
| <table> |
| <tr> |
| <th></th> |
| <th><em>{{.Filename1}}</em></th> |
| <th><em>{{.Filename2}}</em></th> |
| <th></th> |
| </tr> |
| {{.Diff}} |
| </table> |
| </body> |
| </html> |
| ` |
| |
| func main() { |
| if len(os.Args) != 3 { |
| fmt.Fprintf(os.Stderr, "USAGE: %s <file-1> <file-2>\n", os.Args[0]) |
| os.Exit(1) |
| } |
| http.HandleFunc("/", diffHandler(os.Args[1], os.Args[2])) |
| fmt.Printf("Starting server at %s.\n", hostPort) |
| err := http.ListenAndServe(hostPort, nil) |
| if err != nil { |
| panic(err) |
| } |
| } |
| |
| // diffHandler returns an http.HandlerFunc that serves the diff of the |
| // two given files. |
| func diffHandler(filename1, filename2 string) http.HandlerFunc { |
| diff := difflib.HTMLDiff(fileToLines(filename1), fileToLines(filename2)) |
| tmpl, _ := template.New("diffTemplate").Parse(templateString) |
| return func(w http.ResponseWriter, r *http.Request) { |
| err := tmpl.Execute(w, map[string]interface{}{ |
| "Diff": template.HTML(diff), |
| "Filename1": filename1, |
| "Filename2": filename2, |
| }) |
| if err != nil { |
| http.Error(w, err.Error(), http.StatusInternalServerError) |
| } |
| } |
| } |
| |
| // filesToLines takes a path to a file and returns a string array of |
| // the lines in the file. Any HTML in the file is escaped. |
| func fileToLines(filename string) []string { |
| contents, _ := ioutil.ReadFile(filename) |
| return strings.Split(html.EscapeString(string(contents)), "\n") |
| } |
