github.com/jonsyu1/godel@v0.0.0-20171017211503-64567a0cf169/apps/distgo/pkg/script/script.go (about)

     1  // Copyright 2016 Palantir Technologies, Inc.
     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  package script
    16  
    17  import (
    18  	"bytes"
    19  	"fmt"
    20  	"io"
    21  	"io/ioutil"
    22  	"os"
    23  	"os/exec"
    24  	"strings"
    25  
    26  	"github.com/pkg/errors"
    27  
    28  	"github.com/palantir/godel/apps/distgo/params"
    29  )
    30  
    31  func Write(buildSpec params.ProductBuildSpec, script string) (name string, cleanup func() error, rErr error) {
    32  	tmpFile, err := ioutil.TempFile(buildSpec.ProjectDir, "")
    33  	if err != nil {
    34  		return "", nil, errors.Wrapf(err, "Failed to create script file")
    35  	}
    36  	cleanup = func() error {
    37  		return os.Remove(tmpFile.Name())
    38  	}
    39  	// clean up unless everything below succeeds
    40  	runCleanup := true
    41  	defer func() {
    42  		if runCleanup {
    43  			if err := cleanup(); err != nil && rErr == nil {
    44  				rErr = errors.Wrapf(err, "failed to remove script file %s", tmpFile.Name())
    45  			}
    46  		}
    47  	}()
    48  
    49  	if _, err := tmpFile.WriteString(fmt.Sprintf("#!/bin/bash\n%v", script)); err != nil {
    50  		return "", nil, errors.Wrapf(err, "Failed to write script file")
    51  	}
    52  
    53  	if err := tmpFile.Close(); err != nil {
    54  		return "", nil, errors.Wrapf(err, "Failed to close %v", tmpFile.Name())
    55  	}
    56  
    57  	if err := os.Chmod(tmpFile.Name(), 0755); err != nil {
    58  		return "", nil, errors.Wrapf(err, "Failed to set file mode of %v to 0755", tmpFile.Name())
    59  	}
    60  
    61  	runCleanup = false
    62  	return tmpFile.Name(), cleanup, nil
    63  }
    64  
    65  func WriteAndExecute(buildSpec params.ProductBuildSpec, script string, stdOut, stdErr io.Writer, additionalEnvVars map[string]string) (rErr error) {
    66  	// if script exists, write it as a temporary file and execute it
    67  	if script != "" {
    68  		tmpFile, cleanup, err := Write(buildSpec, script)
    69  		if err != nil {
    70  			return err
    71  		}
    72  		defer func() {
    73  			if err := cleanup(); err != nil && rErr == nil {
    74  				rErr = errors.Wrapf(err, "failed to remove script file %s", tmpFile)
    75  			}
    76  		}()
    77  
    78  		currEnv := os.Environ()
    79  		distEnvVars := additionalEnvVars
    80  		env := make([]string, len(currEnv), len(currEnv)+len(distEnvVars))
    81  		copy(env, currEnv)
    82  		for k, v := range distEnvVars {
    83  			env = append(env, fmt.Sprintf("%v=%v", k, v))
    84  		}
    85  
    86  		cmd := exec.Command(tmpFile)
    87  		cmd.Env = env
    88  		cmd.Dir = buildSpec.ProjectDir
    89  		cmd.Stdout = stdOut
    90  		cmd.Stderr = stdErr
    91  		if err := cmd.Run(); err != nil {
    92  			return errors.Wrapf(err, "Dist script for %v failed", buildSpec.ProductName)
    93  		}
    94  	}
    95  	return nil
    96  }
    97  
    98  func GetBuildArgs(buildSpec params.ProductBuildSpec, script string) ([]string, error) {
    99  	stdoutBuf := bytes.Buffer{}
   100  	stderrBuf := bytes.Buffer{}
   101  	combinedBuf := bytes.Buffer{}
   102  	stdoutMW := io.MultiWriter(&stdoutBuf, &combinedBuf)
   103  	stderrMW := io.MultiWriter(&stderrBuf, &combinedBuf)
   104  	if err := WriteAndExecute(buildSpec, script, stdoutMW, stderrMW, nil); err != nil || stderrBuf.String() != "" {
   105  		return nil, errors.Wrapf(err, "failed to execute build args script for %v: %v", buildSpec.ProductName, combinedBuf.String())
   106  	}
   107  
   108  	buildArgsString := strings.TrimSpace(stdoutBuf.String())
   109  	if buildArgsString == "" {
   110  		return nil, nil
   111  	}
   112  	return strings.Split(buildArgsString, "\n"), nil
   113  }