Added csv, tsv output formats

examples/data1.yaml

@@ -1,2 +1 @@
-a:
-  include: 'data2.yaml'
+["a a", "b		thing", 1, true]

pkg/yqlib/encoder_csv.go

@@ -0,0 +1,38 @@
+package yqlib
+
+import (
+	"encoding/csv"
+	"fmt"
+	"io"
+
+	yaml "gopkg.in/yaml.v3"
+)
+
+type csvEncoder struct {
+	destination csv.Writer
+}
+
+func NewCsvEncoder(destination io.Writer, separator rune) Encoder {
+	csvWriter := *csv.NewWriter(destination)
+	csvWriter.Comma = separator
+	return &csvEncoder{csvWriter}
+}
+
+func (e *csvEncoder) Encode(originalNode *yaml.Node) error {
+	// node must be a sequence
+	node := unwrapDoc(originalNode)
+	if node.Kind != yaml.SequenceNode {
+		return fmt.Errorf("csv encoding only works for arrays of scalars (string/numbers/booleans), got: %v", node.Tag)
+	}
+
+	stringValues := make([]string, len(node.Content))
+
+	for i, child := range node.Content {
+
+		if child.Kind != yaml.ScalarNode {
+			return fmt.Errorf("csv encoding only works for arrays of scalars (string/numbers/booleans), child[%v] is a %v", i, child.Tag)
+		}
+		stringValues[i] = child.Value
+	}
+	return e.destination.Write(stringValues)
+}

pkg/yqlib/expression_tokeniser.go

@@ -325,11 +325,21 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`to_json\([0-9]+\)`), encodeWithIndent(JsonOutputFormat))
 
 	lexer.Add([]byte(`toyaml`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: YamlOutputFormat, indent: 2}))
+	lexer.Add([]byte(`@yaml`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: YamlOutputFormat, indent: 0}))
+
 	lexer.Add([]byte(`tojson`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: JsonOutputFormat, indent: 2}))
 	lexer.Add([]byte(`toprops`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: PropsOutputFormat, indent: 2}))
 
 	lexer.Add([]byte(`to_yaml`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: YamlOutputFormat, indent: 2}))
 	lexer.Add([]byte(`to_json`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: JsonOutputFormat, indent: 2}))
+	lexer.Add([]byte(`@json`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: JsonOutputFormat, indent: 0}))
+
+	lexer.Add([]byte(`to_csv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: CsvOutputFormat}))
+	lexer.Add([]byte(`@csv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: CsvOutputFormat}))
+
+	lexer.Add([]byte(`to_tsv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: TsvOutputFormat}))
+	lexer.Add([]byte(`@tsv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: TsvOutputFormat}))
+
 	lexer.Add([]byte(`to_props`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: PropsOutputFormat, indent: 2}))
 
 	lexer.Add([]byte(`fromyaml`), opToken(decodeOpType))

pkg/yqlib/printer.go

@@ -23,6 +23,8 @@ const (
 	YamlOutputFormat = 1 << iota
 	JsonOutputFormat
 	PropsOutputFormat
+	CsvOutputFormat
+	TsvOutputFormat
 )
 
 func OutputFormatFromString(format string) (PrinterOutputFormat, error) {
@@ -33,8 +35,12 @@ func OutputFormatFromString(format string) (PrinterOutputFormat, error) {
 		return JsonOutputFormat, nil
 	case "props", "p":
 		return PropsOutputFormat, nil
+	case "csv", "c":
+		return CsvOutputFormat, nil
+	case "tsv", "t":
+		return TsvOutputFormat, nil
 	default:
-		return 0, fmt.Errorf("Unknown fromat '%v' please use [yaml|json|props]", format)
+		return 0, fmt.Errorf("unknown format '%v' please use [yaml|json|props|csv|tsv]", format)
 	}
 }
 
@@ -87,13 +93,19 @@ func (p *resultsPrinter) printNode(node *yaml.Node, writer io.Writer) error {
 		return writeString(writer, node.Value+"\n")
 	}
 
-	if p.outputFormat == JsonOutputFormat {
+	switch p.outputFormat {
+	case JsonOutputFormat:
 		encoder = NewJsonEncoder(writer, p.indent)
-	} else if p.outputFormat == PropsOutputFormat {
+	case PropsOutputFormat:
 		encoder = NewPropertiesEncoder(writer)
-	} else {
+	case CsvOutputFormat:
+		encoder = NewCsvEncoder(writer, ',')
+	case TsvOutputFormat:
+		encoder = NewCsvEncoder(writer, '\t')
+	case YamlOutputFormat:
 		encoder = NewYamlEncoder(writer, p.indent, p.colorsEnabled)
 	}
+
 	return encoder.Encode(node)
 }
 

test.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+# load array into a bash array
+# need to output each entry as a single line
+# readarray identityMappings < <(./yq e -o=j -I=0 '.identitymappings[]' test.yml )
+
+# for identityMapping in "${identityMappings[@]}"; do
+#     # identity mapping is a yaml snippet representing a single entry
+#     roleArn=$(echo "$identityMapping" | yq e '.arn' -)
+#     echo "roleArn: $roleArn"
+# done
+
+
+
+
+while IFS=$'\t' read -r roleArn group user _; do
+  echo "Role:  $roleArn"
+  echo "Group: $group"
+  echo "User:  $user"
+done < <(yq -j read test.yaml \
+         | jq -r '.identitymappings[] | [.arn, .group, .user] | @tsv')