1// Copyright (C) MongoDB, Inc. 2014-present.
2//
3// Licensed under the Apache License, Version 2.0 (the "License"); you may
4// not use this file except in compliance with the License. You may obtain
5// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
6
7// Main package for the mongoexport tool.
8package main
9
10import (
11	"os"
12
13	"github.com/mongodb/mongo-tools-common/log"
14	"github.com/mongodb/mongo-tools-common/signals"
15	"github.com/mongodb/mongo-tools-common/util"
16	"github.com/mongodb/mongo-tools/mongoexport"
17)
18
19var (
20	VersionStr = "built-without-version-string"
21	GitCommit  = "build-without-git-commit"
22)
23
24func main() {
25	opts, err := mongoexport.ParseOptions(os.Args[1:], VersionStr, GitCommit)
26	if err != nil {
27		log.Logvf(log.Always, "error parsing command line options: %v", err)
28		log.Logvf(log.Always, util.ShortUsage("mongoexport"))
29		os.Exit(util.ExitFailure)
30	}
31
32	signals.Handle()
33
34	// print help, if specified
35	if opts.PrintHelp(false) {
36		return
37	}
38
39	// print version, if specified
40	if opts.PrintVersion() {
41		return
42	}
43
44	exporter, err := mongoexport.New(opts)
45	if err != nil {
46		log.Logvf(log.Always, "%v", err)
47
48		if se, ok := err.(util.SetupError); ok && se.Message != "" {
49			log.Logv(log.Always, se.Message)
50		}
51
52		os.Exit(util.ExitFailure)
53	}
54	defer exporter.Close()
55
56	writer, err := exporter.GetOutputWriter()
57	if err != nil {
58		log.Logvf(log.Always, "error opening output stream: %v", err)
59		os.Exit(util.ExitFailure)
60	}
61	if writer == nil {
62		writer = os.Stdout
63	} else {
64		defer writer.Close()
65	}
66
67	numDocs, err := exporter.Export(writer)
68	if err != nil {
69		log.Logvf(log.Always, "Failed: %v", err)
70		os.Exit(util.ExitFailure)
71	}
72
73	if numDocs == 1 {
74		log.Logvf(log.Always, "exported %v record", numDocs)
75	} else {
76		log.Logvf(log.Always, "exported %v records", numDocs)
77	}
78
79}
80