yq/cmd/evalute_sequence_command.go
Mike Farah 23d3d962e0 Refactored decoder responsibilities
- improved comment handling
- yaml decoder now responsible for leading content work around
2022-10-28 14:05:20 +11:00

142 lines
3.5 KiB
Go

package cmd
import (
"errors"
"fmt"
"github.com/mikefarah/yq/v4/pkg/yqlib"
"github.com/spf13/cobra"
)
func createEvaluateSequenceCommand() *cobra.Command {
var cmdEvalSequence = &cobra.Command{
Use: "eval [expression] [yaml_file1]...",
Aliases: []string{"e"},
Short: "(default) Apply the expression to each document in each yaml file in sequence",
Example: `
# Reads field under the given path for each file
yq e '.a.b' f1.yml f2.yml
# Prints out the file
yq e sample.yaml
# Pipe from STDIN
## use '-' as a filename to pipe from STDIN
cat file2.yml | yq e '.a.b' file1.yml - file3.yml
# Creates a new yaml document
## Note that editing an empty file does not work.
yq e -n '.a.b.c = "cat"'
# Update a file inplace
yq e '.a.b = "cool"' -i file.yaml
`,
Long: `yq is a portable command-line YAML processor (https://github.com/mikefarah/yq/)
See https://mikefarah.gitbook.io/yq/ for detailed documentation and examples.
## Evaluate Sequence ##
This command iterates over each yaml document from each given file, applies the
expression and prints the result in sequence.`,
RunE: evaluateSequence,
}
return cmdEvalSequence
}
func processExpression(expression string) string {
if prettyPrint && expression == "" {
return yqlib.PrettyPrintExp
} else if prettyPrint {
return fmt.Sprintf("%v | %v", expression, yqlib.PrettyPrintExp)
}
return expression
}
func evaluateSequence(cmd *cobra.Command, args []string) (cmdError error) {
// 0 args, read std in
// 1 arg, null input, process expression
// 1 arg, read file in sequence
// 2+ args, [0] = expression, file the rest
out := cmd.OutOrStdout()
var err error
expression, args, err := initCommand(cmd, args)
if err != nil {
return err
}
if writeInplace {
// only use colors if its forced
colorsEnabled = forceColor
writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[0])
out, err = writeInPlaceHandler.CreateTempFile()
if err != nil {
return err
}
// need to indirectly call the function so that completedSuccessfully is
// passed when we finish execution as opposed to now
defer func() {
if cmdError == nil {
cmdError = writeInPlaceHandler.FinishWriteInPlace(completedSuccessfully)
}
}()
}
format, err := yqlib.OutputFormatFromString(outputFormat)
if err != nil {
return err
}
printerWriter, err := configurePrinterWriter(format, out)
if err != nil {
return err
}
encoder := configureEncoder(format)
printer := yqlib.NewPrinter(encoder, printerWriter)
decoder, err := configureDecoder(false)
if err != nil {
return err
}
streamEvaluator := yqlib.NewStreamEvaluator()
if frontMatter != "" {
yqlib.GetLogger().Debug("using front matter handler")
frontMatterHandler := yqlib.NewFrontMatterHandler(args[0])
err = frontMatterHandler.Split()
if err != nil {
return err
}
args[0] = frontMatterHandler.GetYamlFrontMatterFilename()
if frontMatter == "process" {
reader := frontMatterHandler.GetContentReader()
printer.SetAppendix(reader)
defer yqlib.SafelyCloseReader(reader)
}
defer frontMatterHandler.CleanUp()
}
switch len(args) {
case 0:
if nullInput {
err = streamEvaluator.EvaluateNew(processExpression(expression), printer)
} else {
cmd.Println(cmd.UsageString())
return nil
}
default:
err = streamEvaluator.EvaluateFiles(processExpression(expression), args, printer, decoder)
}
completedSuccessfully = err == nil
if err == nil && exitStatus && !printer.PrintedAnything() {
return errors.New("no matches found")
}
return err
}