minio/pkg/quick/errorutil.go

141 lines
3.6 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"
"errors"
"fmt"
"io"
"github.com/cheggaaa/pb"
"github.com/tidwall/gjson"
)
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:])
}
// doCheckDupJSONKeys recursively detects duplicate json keys
func doCheckDupJSONKeys(key, value gjson.Result) error {
// Key occurrences map of the current scope to count
// if there is any duplicated json key.
keysOcc := make(map[string]int)
// Holds the found error
var checkErr error
// Iterate over keys in the current json scope
value.ForEach(func(k, v gjson.Result) bool {
// If current key is not null, check if its
// value contains some duplicated keys.
if k.Type != gjson.Null {
keysOcc[k.String()]++
checkErr = doCheckDupJSONKeys(k, v)
}
return checkErr == nil
})
// Check found err
if checkErr != nil {
return errors.New(key.String() + " => " + checkErr.Error())
}
// Check for duplicated keys
for k, v := range keysOcc {
if v > 1 {
return errors.New(key.String() + " => `" + k + "` entry is duplicated")
}
}
return nil
}
// Check recursively if a key is duplicated in the same json scope
// e.g.:
// `{ "key" : { "key" ..` is accepted
// `{ "key" : { "subkey" : "val1", "subkey": "val2" ..` throws subkey duplicated error
func checkDupJSONKeys(json string) error {
// Parse config with gjson library
config := gjson.Parse(json)
// Create a fake rootKey since root json doesn't seem to have representation
// in gjson library.
rootKey := gjson.Result{Type: gjson.String, Str: "config.json"}
// Check if loaded json contains any duplicated keys
return doCheckDupJSONKeys(rootKey, config)
}
// CheckDuplicateKeys - checks for duplicate entries in a JSON file
func CheckDuplicateKeys(json string) error {
return checkDupJSONKeys(json)
}