1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
// Copyright (C) MongoDB, Inc. 2014-present.
//
// 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
package mongoimport
import (
"bufio"
"fmt"
"io"
"strings"
"go.mongodb.org/mongo-driver/bson"
)
const (
entryDelimiter = '\n'
tokenSeparator = "\t"
)
// TSVInputReader is a struct that implements the InputReader interface for a
// TSV input source.
type TSVInputReader struct {
// colSpecs is a list of column specifications in the BSON documents to be imported
colSpecs []ColumnSpec
// tsvReader is the underlying reader used to read data in from the TSV
// or TSV file
tsvReader *bufio.Reader
// tsvRejectWriter is where coercion-failed rows are written, if applicable
tsvRejectWriter io.Writer
// tsvRecord stores each line of input we read from the underlying reader
tsvRecord string
// numProcessed tracks the number of TSV records processed by the underlying reader
numProcessed uint64
// numDecoders is the number of concurrent goroutines to use for decoding
numDecoders int
// embedded sizeTracker exposes the Size() method to check the number of bytes read so far
sizeTracker
// ignoreBlanks is whether empty fields should be ignored
ignoreBlanks bool
}
// TSVConverter implements the Converter interface for TSV input.
type TSVConverter struct {
colSpecs []ColumnSpec
data string
index uint64
ignoreBlanks bool
rejectWriter io.Writer
}
// NewTSVInputReader returns a TSVInputReader configured to read input from the
// given io.Reader, extracting the specified columns only.
func NewTSVInputReader(colSpecs []ColumnSpec, in io.Reader, rejects io.Writer, numDecoders int, ignoreBlanks bool) *TSVInputReader {
szCount := newSizeTrackingReader(newBomDiscardingReader(in))
return &TSVInputReader{
colSpecs: colSpecs,
tsvReader: bufio.NewReader(szCount),
tsvRejectWriter: rejects,
numProcessed: uint64(0),
numDecoders: numDecoders,
sizeTracker: szCount,
ignoreBlanks: ignoreBlanks,
}
}
// ReadAndValidateHeader reads the header from the underlying reader and validates
// the header fields. It sets err if the read/validation fails.
func (r *TSVInputReader) ReadAndValidateHeader() (err error) {
header, err := r.tsvReader.ReadString(entryDelimiter)
if err != nil {
return err
}
for _, field := range strings.Split(header, tokenSeparator) {
r.colSpecs = append(r.colSpecs, ColumnSpec{
Name: strings.TrimRight(field, "\r\n"),
Parser: new(FieldAutoParser),
})
}
return validateReaderFields(ColumnNames(r.colSpecs))
}
// ReadAndValidateTypedHeader reads the header from the underlying reader and validates
// the header fields. It sets err if the read/validation fails.
func (r *TSVInputReader) ReadAndValidateTypedHeader(parseGrace ParseGrace) (err error) {
header, err := r.tsvReader.ReadString(entryDelimiter)
if err != nil {
return err
}
var headerFields []string
for _, field := range strings.Split(header, tokenSeparator) {
headerFields = append(headerFields, strings.TrimRight(field, "\r\n"))
}
r.colSpecs, err = ParseTypedHeaders(headerFields, parseGrace)
if err != nil {
return err
}
return validateReaderFields(ColumnNames(r.colSpecs))
}
// StreamDocument takes a boolean indicating if the documents should be streamed
// in read order and a channel on which to stream the documents processed from
// the underlying reader. Returns a non-nil error if streaming fails.
func (r *TSVInputReader) StreamDocument(ordered bool, readDocs chan bson.D) (retErr error) {
tsvRecordChan := make(chan Converter, r.numDecoders)
tsvErrChan := make(chan error)
// begin reading from source
go func() {
var err error
for {
r.tsvRecord, err = r.tsvReader.ReadString(entryDelimiter)
if err != nil {
close(tsvRecordChan)
if err == io.EOF {
tsvErrChan <- nil
} else {
r.numProcessed++
tsvErrChan <- fmt.Errorf("read error on entry #%v: %v", r.numProcessed, err)
}
return
}
tsvRecordChan <- TSVConverter{
colSpecs: r.colSpecs,
data: r.tsvRecord,
index: r.numProcessed,
ignoreBlanks: r.ignoreBlanks,
rejectWriter: r.tsvRejectWriter,
}
r.numProcessed++
}
}()
// begin processing read bytes
go func() {
tsvErrChan <- streamDocuments(ordered, r.numDecoders, tsvRecordChan, readDocs)
}()
return channelQuorumError(tsvErrChan, 2)
}
// Convert implements the Converter interface for TSV input. It converts a
// TSVConverter struct to a BSON document.
func (c TSVConverter) Convert() (b bson.D, err error) {
b, err = tokensToBSON(
c.colSpecs,
strings.Split(strings.TrimRight(c.data, "\r\n"), tokenSeparator),
c.index,
c.ignoreBlanks,
)
if _, ok := err.(coercionError); ok {
c.Print()
err = nil
}
return
}
func (c TSVConverter) Print() {
c.rejectWriter.Write([]byte(c.data + "\n"))
}
|
