yq/cmd/evalute_sequence_command.go
2021-04-19 10:27:01 +10:00

125 lines
3.2 KiB
Go

package cmd
import (
"errors"
"fmt"
"os"
"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: "Apply expression to each document in each yaml file given in sequence",
Example: `
# runs the expression against each file, in series
yq e '.a.b | length' f1.yml f2.yml
# prints out the file
yq e sample.yaml
# use '-' as a filename to read from STDIN
cat file2.yml | yq e '.a.b' file1.yml - file3.yml
# prints a new yaml document
yq e -n '.a.b.c = "cat"'
# updates file.yaml directly
yq e '.a.b = "cool"' -i file.yaml
`,
Long: "Evaluate Sequence:\nIterate over each yaml document, apply the expression and print the results, in sequence.",
RunE: evaluateSequence,
}
return cmdEvalSequence
}
func processExpression(expression string) string {
if prettyPrint && expression == "" {
return `... style=""`
} else if prettyPrint {
return fmt.Sprintf("%v | ... style= \"\"", expression)
}
return expression
}
func evaluateSequence(cmd *cobra.Command, args []string) error {
cmd.SilenceUsage = true
// 0 args, read std in
// 1 arg, null input, process expression
// 1 arg, read file in sequence
// 2+ args, [0] = expression, file the rest
var err error
stat, _ := os.Stdin.Stat()
pipingStdIn := (stat.Mode() & os.ModeCharDevice) == 0
out := cmd.OutOrStdout()
fileInfo, _ := os.Stdout.Stat()
if forceColor || (!forceNoColor && (fileInfo.Mode()&os.ModeCharDevice) != 0) {
colorsEnabled = true
}
firstFileIndex := -1
if !nullInput && len(args) == 1 {
firstFileIndex = 0
} else if len(args) > 1 {
firstFileIndex = 1
}
if writeInplace && (firstFileIndex == -1) {
return fmt.Errorf("Write inplace flag only applicable when giving an expression and at least one file")
}
if writeInplace {
// only use colors if its forced
colorsEnabled = forceColor
writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[firstFileIndex])
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() { writeInPlaceHandler.FinishWriteInPlace(completedSuccessfully) }()
}
printer := yqlib.NewPrinter(out, outputToJSON, unwrapScalar, colorsEnabled, indent, !noDocSeparators)
streamEvaluator := yqlib.NewStreamEvaluator()
if nullInput && len(args) > 1 {
return errors.New("Cannot pass files in when using null-input flag")
}
switch len(args) {
case 0:
if pipingStdIn {
err = streamEvaluator.EvaluateFiles(processExpression(""), []string{"-"}, printer)
} else {
cmd.Println(cmd.UsageString())
return nil
}
case 1:
if nullInput {
err = streamEvaluator.EvaluateNew(processExpression(args[0]), printer)
} else {
err = streamEvaluator.EvaluateFiles(processExpression(""), []string{args[0]}, printer)
}
default:
err = streamEvaluator.EvaluateFiles(processExpression(args[0]), args[1:], printer)
}
completedSuccessfully = err == nil
if err == nil && exitStatus && !printer.PrintedAnything() {
return errors.New("no matches found")
}
return err
}