kythe.io@v0.0.68-0.20240422202219-7225dbc01741/kythe/go/extractors/cmd/bazel/copy_kzip/copy_kzip.go (about)

     1  /*
     2   * Copyright 2020 The Kythe Authors. All rights reserved.
     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  // Program copy_kzip implements a Bazel extra action that directly copies a Kythe
    18  // compilation record produced by a "spawn" action.
    19  package main
    20  
    21  import (
    22  	"context"
    23  	"flag"
    24  	"io"
    25  	"time"
    26  
    27  	"kythe.io/kythe/go/extractors/bazel"
    28  	"kythe.io/kythe/go/platform/vfs"
    29  	"kythe.io/kythe/go/util/log"
    30  )
    31  
    32  var (
    33  	outputPath  = flag.String("output", "", "Path of output index file (required)")
    34  	extraAction = flag.String("extra_action", "", "Path of the SpawnAction file (required)")
    35  )
    36  
    37  func main() {
    38  	flag.Parse()
    39  
    40  	// Verify that required flags are set.
    41  	if *outputPath == "" {
    42  		log.Fatal("You must provide a non-empty --output file path")
    43  	}
    44  	if *extraAction == "" {
    45  		log.Fatal("You must provide a non-empty --extra_action file path")
    46  	}
    47  
    48  	info, err := bazel.LoadAction(*extraAction)
    49  	if err != nil {
    50  		log.Fatalf("Unable to load extra action: %v", err)
    51  	}
    52  	start := time.Now()
    53  	ai, err := bazel.SpawnAction(info)
    54  	if err != nil {
    55  		log.Fatalf("Unable to read SpawnInfo: %v", err)
    56  	}
    57  	if len(ai.Outputs) != 1 {
    58  		log.Fatalf("Can only copy a single output kzip, not %d", len(ai.Outputs))
    59  	}
    60  
    61  	if err := copyFile(ai.Outputs[0], *outputPath); err != nil {
    62  		log.Fatalf("Unable to copy input to output: %v", err)
    63  	}
    64  
    65  	log.Infof("Finished extracting [%v elapsed]", time.Since(start))
    66  }
    67  
    68  func copyFile(input, output string) error {
    69  	ctx := context.Background()
    70  	f, err := vfs.Open(ctx, input)
    71  	if err != nil {
    72  		return err
    73  	}
    74  	defer f.Close()
    75  
    76  	o, err := vfs.Create(ctx, output)
    77  	if err != nil {
    78  		return err
    79  	}
    80  
    81  	if _, err := io.Copy(o, f); err != nil {
    82  		o.Close()
    83  		return err
    84  	}
    85  
    86  	return o.Close()
    87  }