github.com/olivere/camlistore@v0.0.0-20140121221811-1b7ac2da0199/dev/update_closure_compiler.go (about)

     1  /*
     2  Copyright 2013 The Camlistore Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8       http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  // update_closure_compiler downloads a new version
    18  // of the closure compiler if the one in tmp/closure-compiler
    19  // doesn't exist or is older than the requested version.
    20  package main
    21  
    22  import (
    23  	"archive/zip"
    24  	"io"
    25  	"log"
    26  	"net/http"
    27  	"os"
    28  	"os/exec"
    29  	"path/filepath"
    30  	"regexp"
    31  
    32  	"camlistore.org/pkg/osutil"
    33  )
    34  
    35  const (
    36  	compilerDirURL  = "http://closure-compiler.googlecode.com/files/"
    37  	compilerVersion = "20121212"
    38  )
    39  
    40  var rgxVersion = regexp.MustCompile(`.*Version: (.*) \(revision.*`)
    41  
    42  func main() {
    43  
    44  	// check JRE presence
    45  	_, err := exec.LookPath("java")
    46  	if err != nil {
    47  		log.Fatal("Didn't find 'java' in $PATH. The Java Runtime Environment is needed to run the closure compiler.\n")
    48  	}
    49  
    50  	camliRootPath, err := osutil.GoPackagePath("camlistore.org")
    51  	if err != nil {
    52  		log.Fatal("Package camlistore.org not found in $GOPATH (or $GOPATH not defined).")
    53  	}
    54  	destDir := filepath.Join(camliRootPath, "tmp", "closure-compiler")
    55  	// check if compiler already exists
    56  	jarFile := filepath.Join(destDir, "compiler.jar")
    57  	_, err = os.Stat(jarFile)
    58  	if err == nil {
    59  		// if compiler exists, check version
    60  		cmd := exec.Command("java", "-jar", jarFile, "--version", "--help", "2>&1")
    61  		output, _ := cmd.CombinedOutput()
    62  		m := rgxVersion.FindStringSubmatch(string(output))
    63  		if m == nil {
    64  			log.Fatalf("Could not find compiler version in %q", output)
    65  		}
    66  		if m[1] == compilerVersion {
    67  			log.Printf("compiler already at version %v , nothing to do.", compilerVersion)
    68  			os.Exit(0)
    69  		}
    70  		if err := os.Remove(jarFile); err != nil {
    71  			log.Fatalf("Could not remove %v: %v", jarFile, err)
    72  		}
    73  	} else {
    74  		if !os.IsNotExist(err) {
    75  			log.Fatalf("Could not stat %v: %v", jarFile, err)
    76  		}
    77  	}
    78  
    79  	// otherwise, download compiler
    80  	log.Printf("Getting closure compiler version %s.\n", compilerVersion)
    81  	if err := os.MkdirAll(destDir, 0755); err != nil {
    82  		log.Fatal(err)
    83  	}
    84  	if err := os.Chdir(destDir); err != nil {
    85  		log.Fatal(err)
    86  	}
    87  	zipFilename := "compiler-" + compilerVersion + ".zip"
    88  	compilerURL := compilerDirURL + zipFilename
    89  	resp, err := http.Get(compilerURL)
    90  	if err != nil {
    91  		log.Fatal(err)
    92  	}
    93  	defer resp.Body.Close()
    94  	f, err := os.Create(zipFilename)
    95  	if err != nil {
    96  		log.Fatal(err)
    97  	}
    98  	if _, err := io.Copy(f, resp.Body); err != nil {
    99  		log.Fatal(err)
   100  	}
   101  	if err := f.Close(); err != nil {
   102  		log.Fatal(err)
   103  	}
   104  
   105  	r, err := zip.OpenReader(zipFilename)
   106  	if err != nil {
   107  		log.Fatal(err)
   108  	}
   109  	for x, f := range r.File {
   110  		if f.FileHeader.Name != "compiler.jar" {
   111  			if x == len(r.File)-1 {
   112  				log.Fatal("compiler.jar was not found in the zip archive")
   113  			}
   114  			continue
   115  		}
   116  		rc, err := f.Open()
   117  		if err != nil {
   118  			log.Fatal(err)
   119  		}
   120  		g, err := os.Create(jarFile)
   121  		if err != nil {
   122  			log.Fatal(err)
   123  		}
   124  		defer g.Close()
   125  		if _, err = io.Copy(g, rc); err != nil {
   126  			log.Fatal(err)
   127  		}
   128  		rc.Close()
   129  		break
   130  	}
   131  
   132  	if err := r.Close(); err != nil {
   133  		log.Fatal(err)
   134  	}
   135  	if err := os.Remove(zipFilename); err != nil {
   136  		log.Fatal(err)
   137  	}
   138  	log.Printf("Success. Installed at %v", jarFile)
   139  }