frostfs-s3-gw/pkg/quick/errorutil.go

82 lines
2 KiB
Go

/*
* Quick - Quick key value store for config files and persistent state files
*
* Quick (C) 2015 MinIO, Inc.
*
* 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package quick
import (
"bufio"
"bytes"
"fmt"
"io"
"github.com/cheggaaa/pb"
)
const errorFmt = "%5d: %s <<<<"
// FormatJSONSyntaxError generates a pretty printed json syntax error since
// golang doesn't provide an easy way to report the location of the error
func FormatJSONSyntaxError(data io.Reader, offset int64) (highlight string) {
var readLine bytes.Buffer
var errLine = 1
var readBytes int64
bio := bufio.NewReader(data)
// termWidth is set to a default one to use when we are
// not able to calculate terminal width via OS syscalls
termWidth := 25
// errorShift is the length of the minimum needed place for
// error msg accessories, like <--, etc.. We calculate it
// dynamically to avoid an eventual bug after modifying errorFmt
errorShift := len(fmt.Sprintf(errorFmt, 1, ""))
if width, err := pb.GetTerminalWidth(); err == nil {
termWidth = width
}
for {
b, err := bio.ReadByte()
if err != nil {
break
}
readBytes++
if readBytes > offset {
break
}
if b == '\n' {
readLine.Reset()
errLine++
continue
} else if b == '\t' {
readLine.WriteByte(' ')
} else if b == '\r' {
break
}
readLine.WriteByte(b)
}
lineLen := readLine.Len()
idx := lineLen - termWidth + errorShift
if idx < 0 || idx > lineLen-1 {
idx = 0
}
return fmt.Sprintf(errorFmt, errLine, readLine.String()[idx:])
}