yq/pkg/yqlib/operator_encoder_decoder.go
2021-10-30 10:04:41 +11:00

92 lines
2.9 KiB
Go

package yqlib
import (
"bufio"
"bytes"
"container/list"
"regexp"
"strings"
"gopkg.in/yaml.v3"
)
func yamlToString(candidate *CandidateNode, prefs encoderPreferences) (string, error) {
var output bytes.Buffer
log.Debug("printing with indent: %v", prefs.indent)
printer := NewPrinterWithSingleWriter(bufio.NewWriter(&output), prefs.format, true, false, prefs.indent, true)
err := printer.PrintResults(candidate.AsList())
return output.String(), err
}
type encoderPreferences struct {
format PrinterOutputFormat
indent int
}
/* encodes object as yaml string */
func encodeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
preferences := expressionNode.Operation.Preferences.(encoderPreferences)
var results = list.New()
hasOnlyOneNewLine := regexp.MustCompile("[^\n].*\n$")
endWithNewLine := regexp.MustCompile(".*\n$")
chomper := regexp.MustCompile("\n+$")
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
stringValue, err := yamlToString(candidate, preferences)
if err != nil {
return Context{}, err
}
// remove trailing newlines if needed.
// check if we originally decoded this path, and the original thing had a single line.
originalList := context.GetVariable("decoded: " + candidate.GetKey())
if originalList != nil && originalList.Len() > 0 && hasOnlyOneNewLine.MatchString(stringValue) {
original := originalList.Front().Value.(*CandidateNode)
originalNode := unwrapDoc(original.Node)
// original block did not have a new line at the end, get rid of this one too
if !endWithNewLine.MatchString(originalNode.Value) {
stringValue = chomper.ReplaceAllString(stringValue, "")
}
}
// dont print a new line when printing json on a single line.
if preferences.format == JsonOutputFormat && preferences.indent == 0 {
stringValue = chomper.ReplaceAllString(stringValue, "")
}
stringContentNode := &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!str", Value: stringValue}
results.PushBack(candidate.CreateChild(nil, stringContentNode))
}
return context.ChildContext(results), nil
}
/* takes a string and decodes it back into an object */
func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
context.SetVariable("decoded: "+candidate.GetKey(), candidate.AsList())
var dataBucket yaml.Node
log.Debugf("got: [%v]", candidate.Node.Value)
decoder := yaml.NewDecoder(strings.NewReader(unwrapDoc(candidate.Node).Value))
errorReading := decoder.Decode(&dataBucket)
if errorReading != nil {
return Context{}, errorReading
}
//first node is a doc
node := unwrapDoc(&dataBucket)
results.PushBack(candidate.CreateChild(nil, node))
}
return context.ChildContext(results), nil
}