yq/cmd/utils.go
2020-02-03 14:28:38 +11:00

411 lines
12 KiB
Go

package cmd
import (
"bufio"
"fmt"
"io"
"io/ioutil"
"os"
"strconv"
"github.com/mikefarah/yq/v3/pkg/yqlib"
errors "github.com/pkg/errors"
yaml "gopkg.in/yaml.v3"
)
func readYamlFile(filename string, path string, updateAll bool, docIndexInt int) ([]*yqlib.NodeContext, error) {
var matchingNodes []*yqlib.NodeContext
var currentIndex = 0
var errorReadingStream = readStream(filename, func(decoder *yaml.Decoder) error {
for {
var dataBucket yaml.Node
errorReading := decoder.Decode(&dataBucket)
if errorReading == io.EOF {
return handleEOF(updateAll, docIndexInt, currentIndex)
} else if errorReading != nil {
return errorReading
}
var errorParsing error
matchingNodes, errorParsing = appendDocument(matchingNodes, dataBucket, path, updateAll, docIndexInt, currentIndex)
if errorParsing != nil {
return errorParsing
}
if !updateAll && currentIndex == docIndexInt {
log.Debug("all done")
return nil
}
currentIndex = currentIndex + 1
}
})
return matchingNodes, errorReadingStream
}
func handleEOF(updateAll bool, docIndexInt int, currentIndex int) error {
log.Debugf("done %v / %v", currentIndex, docIndexInt)
if !updateAll && currentIndex <= docIndexInt && docIndexInt != 0 {
return fmt.Errorf("Could not process document index %v as there are only %v document(s)", docIndex, currentIndex)
}
return nil
}
func appendDocument(originalMatchingNodes []*yqlib.NodeContext, dataBucket yaml.Node, path string, updateAll bool, docIndexInt int, currentIndex int) ([]*yqlib.NodeContext, error) {
log.Debugf("processing document %v - requested index %v", currentIndex, docIndexInt)
yqlib.DebugNode(&dataBucket)
if !updateAll && currentIndex != docIndexInt {
return originalMatchingNodes, nil
}
log.Debugf("reading %v in document %v", path, currentIndex)
matchingNodes, errorParsing := lib.Get(&dataBucket, path)
if errorParsing != nil {
return nil, errors.Wrapf(errorParsing, "Error reading path in document index %v", currentIndex)
}
return append(originalMatchingNodes, matchingNodes...), nil
}
func printValue(node *yaml.Node, writer io.Writer) error {
if node.Kind == yaml.ScalarNode {
_, errorWriting := writer.Write([]byte(node.Value))
return errorWriting
}
return printNode(node, writer)
}
func printNode(node *yaml.Node, writer io.Writer) error {
var encoder yqlib.Encoder
if outputToJSON {
encoder = yqlib.NewJsonEncoder(writer)
} else {
encoder = yqlib.NewYamlEncoder(writer)
}
return encoder.Encode(node)
}
func setStyle(matchingNodes []*yqlib.NodeContext, style yaml.Style) {
for _, nodeContext := range matchingNodes {
updateStyleOfNode(nodeContext.Node, style)
}
}
func updateStyleOfNode(node *yaml.Node, style yaml.Style) {
node.Style = style
for _, child := range node.Content {
updateStyleOfNode(child, style)
}
}
func writeString(writer io.Writer, txt string) error {
_, errorWriting := writer.Write([]byte(txt))
return errorWriting
}
func printResults(matchingNodes []*yqlib.NodeContext, writer io.Writer) error {
bufferedWriter := bufio.NewWriter(writer)
defer safelyFlush(bufferedWriter)
if len(matchingNodes) == 0 {
log.Debug("no matching results, nothing to print")
if defaultValue != "" {
return writeString(bufferedWriter, defaultValue)
}
return nil
}
var errorWriting error
for index, mappedDoc := range matchingNodes {
switch printMode {
case "p":
errorWriting = writeString(bufferedWriter, lib.PathStackToString(mappedDoc.PathStack))
if errorWriting != nil {
return errorWriting
}
if index < len(matchingNodes)-1 {
errorWriting = writeString(bufferedWriter, "\n")
if errorWriting != nil {
return errorWriting
}
}
case "pv", "vp":
// put it into a node and print that.
var parentNode = yaml.Node{Kind: yaml.MappingNode}
parentNode.Content = make([]*yaml.Node, 2)
parentNode.Content[0] = &yaml.Node{Kind: yaml.ScalarNode, Value: lib.PathStackToString(mappedDoc.PathStack)}
parentNode.Content[1] = mappedDoc.Node
if err := printValue(&parentNode, bufferedWriter); err != nil {
return err
}
default:
if err := printValue(mappedDoc.Node, bufferedWriter); err != nil {
return err
}
// Printing our Scalars does not print a new line at the end
// we only want to do that if there are more values (so users can easily script extraction of values in the yaml)
if index < len(matchingNodes)-1 && mappedDoc.Node.Kind == yaml.ScalarNode {
errorWriting = writeString(bufferedWriter, "\n")
if errorWriting != nil {
return errorWriting
}
}
}
}
return nil
}
func parseDocumentIndex() (bool, int, error) {
if docIndex == "*" {
return true, -1, nil
}
docIndexInt64, err := strconv.ParseInt(docIndex, 10, 32)
if err != nil {
return false, -1, errors.Wrapf(err, "Document index %v is not a integer or *", docIndex)
}
return false, int(docIndexInt64), nil
}
type updateDataFn func(dataBucket *yaml.Node, currentIndex int) error
func mapYamlDecoder(updateData updateDataFn, encoder yqlib.Encoder) yamlDecoderFn {
return func(decoder *yaml.Decoder) error {
var dataBucket yaml.Node
var errorReading error
var errorWriting error
var errorUpdating error
var currentIndex = 0
var updateAll, docIndexInt, errorParsingDocIndex = parseDocumentIndex()
if errorParsingDocIndex != nil {
return errorParsingDocIndex
}
for {
log.Debugf("Read doc %v", currentIndex)
errorReading = decoder.Decode(&dataBucket)
if errorReading == io.EOF {
if !updateAll && currentIndex <= docIndexInt {
return fmt.Errorf("asked to process document index %v but there are only %v document(s)", docIndex, currentIndex)
}
return nil
} else if errorReading != nil {
return errors.Wrapf(errorReading, "Error reading document at index %v, %v", currentIndex, errorReading)
}
errorUpdating = updateData(&dataBucket, currentIndex)
if errorUpdating != nil {
return errors.Wrapf(errorUpdating, "Error updating document at index %v", currentIndex)
}
errorWriting = encoder.Encode(&dataBucket)
if errorWriting != nil {
return errors.Wrapf(errorWriting, "Error writing document at index %v, %v", currentIndex, errorWriting)
}
currentIndex = currentIndex + 1
}
}
}
func prefixDocument(updateAll bool, docIndexInt int, currentIndex int, dataBucket *yaml.Node, updateCommand yqlib.UpdateCommand) error {
if updateAll || currentIndex == docIndexInt {
log.Debugf("Prefixing document %v", currentIndex)
yqlib.DebugNode(dataBucket)
updateCommand.Value = dataBucket.Content[0]
dataBucket.Content = make([]*yaml.Node, 1)
newNode := lib.New(updateCommand.Path)
dataBucket.Content[0] = &newNode
errorUpdating := lib.Update(dataBucket, updateCommand, true)
if errorUpdating != nil {
return errorUpdating
}
}
return nil
}
func updateDoc(inputFile string, updateCommands []yqlib.UpdateCommand, writer io.Writer) error {
var updateAll, docIndexInt, errorParsingDocIndex = parseDocumentIndex()
if errorParsingDocIndex != nil {
return errorParsingDocIndex
}
var updateData = func(dataBucket *yaml.Node, currentIndex int) error {
if updateAll || currentIndex == docIndexInt {
log.Debugf("Updating doc %v", currentIndex)
for _, updateCommand := range updateCommands {
log.Debugf("Processing update to Path %v", updateCommand.Path)
errorUpdating := lib.Update(dataBucket, updateCommand, autoCreateFlag)
if errorUpdating != nil {
return errorUpdating
}
}
}
return nil
}
return readAndUpdate(writer, inputFile, updateData)
}
func readAndUpdate(stdOut io.Writer, inputFile string, updateData updateDataFn) error {
var destination io.Writer
var destinationName string
if writeInplace {
info, err := os.Stat(inputFile)
if err != nil {
return err
}
tempFile, err := ioutil.TempFile("", "temp")
if err != nil {
return err
}
destinationName = tempFile.Name()
err = os.Chmod(destinationName, info.Mode())
if err != nil {
return err
}
destination = tempFile
defer func() {
safelyCloseFile(tempFile)
safelyRenameFile(tempFile.Name(), inputFile)
}()
} else {
destination = stdOut
destinationName = "Stdout"
}
log.Debugf("Writing to %v from %v", destinationName, inputFile)
bufferedWriter := bufio.NewWriter(destination)
defer safelyFlush(bufferedWriter)
var encoder yqlib.Encoder
if outputToJSON {
encoder = yqlib.NewJsonEncoder(bufferedWriter)
} else {
encoder = yqlib.NewYamlEncoder(bufferedWriter)
}
return readStream(inputFile, mapYamlDecoder(updateData, encoder))
}
type updateCommandParsed struct {
Command string
Path string
Value yaml.Node
}
func readUpdateCommands(args []string, expectedArgs int, badArgsMessage string) ([]yqlib.UpdateCommand, error) {
var updateCommands []yqlib.UpdateCommand = make([]yqlib.UpdateCommand, 0)
if writeScript != "" {
var parsedCommands = make([]updateCommandParsed, 0)
err := readData(writeScript, 0, &parsedCommands)
if err != nil && err != io.EOF {
return nil, err
}
log.Debugf("Read write commands file '%v'", parsedCommands)
for index := range parsedCommands {
parsedCommand := parsedCommands[index]
updateCommand := yqlib.UpdateCommand{Command: parsedCommand.Command, Path: parsedCommand.Path, Value: &parsedCommand.Value, Overwrite: true}
updateCommands = append(updateCommands, updateCommand)
}
log.Debugf("Read write commands file '%v'", updateCommands)
} else if len(args) < expectedArgs {
return nil, errors.New(badArgsMessage)
} else {
updateCommands = make([]yqlib.UpdateCommand, 1)
log.Debug("args %v", args)
log.Debug("path %v", args[expectedArgs-2])
log.Debug("Value %v", args[expectedArgs-1])
updateCommands[0] = yqlib.UpdateCommand{Command: "update", Path: args[expectedArgs-2], Value: valueParser.Parse(args[expectedArgs-1], customTag), Overwrite: true}
}
return updateCommands, nil
}
func safelyRenameFile(from string, to string) {
if renameError := os.Rename(from, to); renameError != nil {
log.Debugf("Error renaming from %v to %v, attempting to copy contents", from, to)
log.Debug(renameError.Error())
// can't do this rename when running in docker to a file targeted in a mounted volume,
// so gracefully degrade to copying the entire contents.
if copyError := copyFileContents(from, to); copyError != nil {
log.Errorf("Failed copying from %v to %v", from, to)
log.Error(copyError.Error())
} else {
removeErr := os.Remove(from)
if removeErr != nil {
log.Errorf("failed removing original file: %s", from)
}
}
}
}
// thanks https://stackoverflow.com/questions/21060945/simple-way-to-copy-a-file-in-golang
func copyFileContents(src, dst string) (err error) {
in, err := os.Open(src) // nolint gosec
if err != nil {
return err
}
defer safelyCloseFile(in)
out, err := os.Create(dst)
if err != nil {
return err
}
defer safelyCloseFile(out)
if _, err = io.Copy(out, in); err != nil {
return err
}
return out.Sync()
}
func safelyFlush(writer *bufio.Writer) {
if err := writer.Flush(); err != nil {
log.Error("Error flushing writer!")
log.Error(err.Error())
}
}
func safelyCloseFile(file *os.File) {
err := file.Close()
if err != nil {
log.Error("Error closing file!")
log.Error(err.Error())
}
}
type yamlDecoderFn func(*yaml.Decoder) error
func readStream(filename string, yamlDecoder yamlDecoderFn) error {
if filename == "" {
return errors.New("Must provide filename")
}
var stream io.Reader
if filename == "-" {
stream = bufio.NewReader(os.Stdin)
} else {
file, err := os.Open(filename) // nolint gosec
if err != nil {
return err
}
defer safelyCloseFile(file)
stream = file
}
return yamlDecoder(yaml.NewDecoder(stream))
}
func readData(filename string, indexToRead int, parsedData interface{}) error {
return readStream(filename, func(decoder *yaml.Decoder) error {
for currentIndex := 0; currentIndex < indexToRead; currentIndex++ {
errorSkipping := decoder.Decode(parsedData)
if errorSkipping != nil {
return errors.Wrapf(errorSkipping, "Error processing document at index %v, %v", currentIndex, errorSkipping)
}
}
return decoder.Decode(parsedData)
})
}