mysql.*mysqlConn.handleInFileRequest - Code Metrics - Inspection of "ISSUE-22: Add support for sqlite" - fraenky8/tables-to-go - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#23)

by Frank

created 2019-11-18 14:52 UTC

mysql.*mysqlConn.handleInFileRequest F

↳ Parent: vendor/github.com/go-sql-driver/mysql/infile.go

Complexity

Conditions

Size

Total Lines	86
Code Lines	54

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	22
eloc	54
nop	1
dl	0
loc	86
rs	0
c	0
b	0
f	0

How to fix Long Method Complexity

// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
//
// Copyright 2013 The Go-MySQL-Driver Authors. All rights reserved.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at http://mozilla.org/MPL/2.0/.

package mysql

import (
	"fmt"
	"io"
	"os"
	"strings"
	"sync"
)

var (
	fileRegister       map[string]bool
	fileRegisterLock   sync.RWMutex
	readerRegister     map[string]func() io.Reader
	readerRegisterLock sync.RWMutex
)

// RegisterLocalFile adds the given file to the file whitelist,
// so that it can be used by "LOAD DATA LOCAL INFILE <filepath>".
// Alternatively you can allow the use of all local files with
// the DSN parameter 'allowAllFiles=true'
//
//  filePath := "/home/gopher/data.csv"
//  mysql.RegisterLocalFile(filePath)
//  err := db.Exec("LOAD DATA LOCAL INFILE '" + filePath + "' INTO TABLE foo")
//  if err != nil {
//  ...
//
func RegisterLocalFile(filePath string) {
	fileRegisterLock.Lock()
	// lazy map init
	if fileRegister == nil {
		fileRegister = make(map[string]bool)
	}

	fileRegister[strings.Trim(filePath, `"`)] = true
	fileRegisterLock.Unlock()
}

// DeregisterLocalFile removes the given filepath from the whitelist.
func DeregisterLocalFile(filePath string) {
	fileRegisterLock.Lock()
	delete(fileRegister, strings.Trim(filePath, `"`))
	fileRegisterLock.Unlock()
}

// RegisterReaderHandler registers a handler function which is used
// to receive a io.Reader.
// The Reader can be used by "LOAD DATA LOCAL INFILE Reader::<name>".
// If the handler returns a io.ReadCloser Close() is called when the
// request is finished.
//
//  mysql.RegisterReaderHandler("data", func() io.Reader {
//  	var csvReader io.Reader // Some Reader that returns CSV data
//  	... // Open Reader here
//  	return csvReader
//  })
//  err := db.Exec("LOAD DATA LOCAL INFILE 'Reader::data' INTO TABLE foo")
//  if err != nil {
//  ...
//
func RegisterReaderHandler(name string, handler func() io.Reader) {
	readerRegisterLock.Lock()
	// lazy map init
	if readerRegister == nil {
		readerRegister = make(map[string]func() io.Reader)
	}

	readerRegister[name] = handler
	readerRegisterLock.Unlock()
}

// DeregisterReaderHandler removes the ReaderHandler function with
// the given name from the registry.
func DeregisterReaderHandler(name string) {
	readerRegisterLock.Lock()
	delete(readerRegister, name)
	readerRegisterLock.Unlock()
}

func deferredClose(err *error, closer io.Closer) {
	closeErr := closer.Close()
	if *err == nil {
		*err = closeErr
	}
}

func (mc *mysqlConn) handleInFileRequest(name string) (err error) {
	var rdr io.Reader
	var data []byte
	packetSize := 16 * 1024 // 16KB is small enough for disk readahead and large enough for TCP
	if mc.maxWriteSize < packetSize {
		packetSize = mc.maxWriteSize
	}

	if idx := strings.Index(name, "Reader::"); idx == 0 || (idx > 0 && name[idx-1] == '/') { // io.Reader
		// The server might return an an absolute path. See issue #355.
		name = name[idx+8:]

		readerRegisterLock.RLock()
		handler, inMap := readerRegister[name]
		readerRegisterLock.RUnlock()

		if inMap {
			rdr = handler()
			if rdr != nil {
				if cl, ok := rdr.(io.Closer); ok {
					defer deferredClose(&err, cl)
				}
			} else {
				err = fmt.Errorf("Reader '%s' is <nil>", name)
			}
		} else {
			err = fmt.Errorf("Reader '%s' is not registered", name)
		}
	} else { // File
		name = strings.Trim(name, `"`)
		fileRegisterLock.RLock()
		fr := fileRegister[name]
		fileRegisterLock.RUnlock()
		if mc.cfg.AllowAllFiles || fr {
			var file *os.File
			var fi os.FileInfo

			if file, err = os.Open(name); err == nil {
				defer deferredClose(&err, file)

				// get file size
				if fi, err = file.Stat(); err == nil {
					rdr = file
					if fileSize := int(fi.Size()); fileSize < packetSize {
						packetSize = fileSize
					}
				}
			}
		} else {
			err = fmt.Errorf("local file '%s' is not registered", name)
		}
	}

	// send content packets
	// if packetSize == 0, the Reader contains no data
	if err == nil && packetSize > 0 {
		data := make([]byte, 4+packetSize)
		var n int
		for err == nil {
			n, err = rdr.Read(data[4:])
			if n > 0 {
				if ioErr := mc.writePacket(data[:4+n]); ioErr != nil {
					return ioErr
				}
			}
		}
		if err == io.EOF {
			err = nil
		}
	}

	// send empty packet (termination)
	if data == nil {
		data = make([]byte, 4)
	}
	if ioErr := mc.writePacket(data[:4]); ioErr != nil {
		return ioErr
	}

	// read OK packet
	if err == nil {
		return mc.readResultOK()
	}

	mc.readPacket()
	return err
}


1			// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
2			//
3			// Copyright 2013 The Go-MySQL-Driver Authors. All rights reserved.
4			//
5			// This Source Code Form is subject to the terms of the Mozilla Public
6			// License, v. 2.0. If a copy of the MPL was not distributed with this file,
7			// You can obtain one at http://mozilla.org/MPL/2.0/.
8
9			package mysql
10
11			import (
12			"fmt"
13			"io"
14			"os"
15			"strings"
16			"sync"
17			)
18
19			var (
20			fileRegister map[string]bool
21			fileRegisterLock sync.RWMutex
22			readerRegister map[string]func() io.Reader
23			readerRegisterLock sync.RWMutex
24			)
25
26			// RegisterLocalFile adds the given file to the file whitelist,
27			// so that it can be used by "LOAD DATA LOCAL INFILE <filepath>".
28			// Alternatively you can allow the use of all local files with
29			// the DSN parameter 'allowAllFiles=true'
30			//
31			// filePath := "/home/gopher/data.csv"
32			// mysql.RegisterLocalFile(filePath)
33			// err := db.Exec("LOAD DATA LOCAL INFILE '" + filePath + "' INTO TABLE foo")
34			// if err != nil {
35			// ...
36			//
37			func RegisterLocalFile(filePath string) {
38			fileRegisterLock.Lock()
39			// lazy map init
40			if fileRegister == nil {
41			fileRegister = make(map[string]bool)
42			}
43
44			fileRegister[strings.Trim(filePath, `"`)] = true
45			fileRegisterLock.Unlock()
46			}
47
48			// DeregisterLocalFile removes the given filepath from the whitelist.
49			func DeregisterLocalFile(filePath string) {
50			fileRegisterLock.Lock()
51			delete(fileRegister, strings.Trim(filePath, `"`))
52			fileRegisterLock.Unlock()
53			}
54
55			// RegisterReaderHandler registers a handler function which is used
56			// to receive a io.Reader.
57			// The Reader can be used by "LOAD DATA LOCAL INFILE Reader::<name>".
58			// If the handler returns a io.ReadCloser Close() is called when the
59			// request is finished.
60			//
61			// mysql.RegisterReaderHandler("data", func() io.Reader {
62			// var csvReader io.Reader // Some Reader that returns CSV data
63			// ... // Open Reader here
64			// return csvReader
65			// })
66			// err := db.Exec("LOAD DATA LOCAL INFILE 'Reader::data' INTO TABLE foo")
67			// if err != nil {
68			// ...
69			//
70			func RegisterReaderHandler(name string, handler func() io.Reader) {
71			readerRegisterLock.Lock()
72			// lazy map init
73			if readerRegister == nil {
74			readerRegister = make(map[string]func() io.Reader)
75			}
76
77			readerRegister[name] = handler
78			readerRegisterLock.Unlock()
79			}
80
81			// DeregisterReaderHandler removes the ReaderHandler function with
82			// the given name from the registry.
83			func DeregisterReaderHandler(name string) {
84			readerRegisterLock.Lock()
85			delete(readerRegister, name)
86			readerRegisterLock.Unlock()
87			}
88
89			func deferredClose(err *error, closer io.Closer) {
90			closeErr := closer.Close()
91			if *err == nil {
92			*err = closeErr
93			}
94			}
95
96			func (mc *mysqlConn) handleInFileRequest(name string) (err error) {
97			var rdr io.Reader
98			var data []byte
99			packetSize := 16 * 1024 // 16KB is small enough for disk readahead and large enough for TCP
100			if mc.maxWriteSize < packetSize {
101			packetSize = mc.maxWriteSize
102			}
103
104			if idx := strings.Index(name, "Reader::"); idx == 0 \|\| (idx > 0 && name[idx-1] == '/') { // io.Reader
105			// The server might return an an absolute path. See issue #355.
106			name = name[idx+8:]
107
108			readerRegisterLock.RLock()
109			handler, inMap := readerRegister[name]
110			readerRegisterLock.RUnlock()
111
112			if inMap {
113			rdr = handler()
114			if rdr != nil {
115			if cl, ok := rdr.(io.Closer); ok {
116			defer deferredClose(&err, cl)
117			}
118			} else {
119			err = fmt.Errorf("Reader '%s' is <nil>", name)
120			}
121			} else {
122			err = fmt.Errorf("Reader '%s' is not registered", name)
123			}
124			} else { // File
125			name = strings.Trim(name, `"`)
126			fileRegisterLock.RLock()
127			fr := fileRegister[name]
128			fileRegisterLock.RUnlock()
129			if mc.cfg.AllowAllFiles \|\| fr {
130			var file *os.File
131			var fi os.FileInfo
132
133			if file, err = os.Open(name); err == nil {
134			defer deferredClose(&err, file)
135
136			// get file size
137			if fi, err = file.Stat(); err == nil {
138			rdr = file
139			if fileSize := int(fi.Size()); fileSize < packetSize {
140			packetSize = fileSize
141			}
142			}
143			}
144			} else {
145			err = fmt.Errorf("local file '%s' is not registered", name)
146			}
147			}
148
149			// send content packets
150			// if packetSize == 0, the Reader contains no data
151			if err == nil && packetSize > 0 {
152			data := make([]byte, 4+packetSize)
153			var n int
154			for err == nil {
155			n, err = rdr.Read(data[4:])
156			if n > 0 {
157			if ioErr := mc.writePacket(data[:4+n]); ioErr != nil {
158			return ioErr
159			}
160			}
161			}
162			if err == io.EOF {
163			err = nil
164			}
165			}
166
167			// send empty packet (termination)
168			if data == nil {
169			data = make([]byte, 4)
170			}
171			if ioErr := mc.writePacket(data[:4]); ioErr != nil {
172			return ioErr
173			}
174
175			// read OK packet
176			if err == nil {
177			return mc.readResultOK()
178			}
179
180			mc.readPacket()
181			return err
182			}
183

fraenky8 / tables-to-go

Pull Request — master (#23)

mysql.*mysqlConn.handleInFileRequest F

Complexity

Size

Duplication

Importance

How to fix Long Method Complexity

Long Method

Complexity

Duplication Side-by-Side

Filter issues like