Fin.

pkg/yqlib/decode_xml_test.go

@@ -88,7 +88,11 @@ func documentXmlScenario(t *testing.T, w *bufio.Writer, i interface{}) {
 
 	node := decodeXml(t, s.inputXml)
 
-	printer.PrintResults(node.AsList())
+	err := printer.PrintResults(node.AsList())
+	if err != nil {
+		t.Error(err)
+		return
+	}
 
 	writeOrPanic(w, fmt.Sprintf("```yaml\n%v```\n\n", output.String()))
 

pkg/yqlib/doc/operators/encode-decode.md

@@ -271,3 +271,19 @@ cat	thing1,thing2	true	3.40
 dog	thing3	false	12
 ```
 
+## Decode a xml encoded string
+Given a sample.yml file of:
+```yaml
+a: <foo>bar</foo>
+```
+then
+```bash
+yq eval '.b = (.a | from_xml)' sample.yml
+```
+will output
+```yaml
+a: <foo>bar</foo>
+b:
+  foo: bar
+```
+

pkg/yqlib/doc/operators/headers/encode-decode.md

@@ -14,6 +14,7 @@ These operators are useful to process yaml documents that have stringified embed
 | Properties |  | to_props/@props |
 | CSV |  | to_csv/@csv |
 | TSV |  | to_tsv/@tsv |
+| XML | from_xml |  |
 
 
 CSV and TSV format both accept either a single array or scalars (representing a single row), or an array of array of scalars (representing multiple rows). 

pkg/yqlib/expression_tokeniser.go

@@ -346,11 +346,13 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`to_tsv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: TsvOutputFormat}))
 	lexer.Add([]byte(`@tsv`), opTokenWithPrefs(encodeOpType, nil, encoderPreferences{format: TsvOutputFormat}))
 
-	lexer.Add([]byte(`fromyaml`), opToken(decodeOpType))
-	lexer.Add([]byte(`fromjson`), opToken(decodeOpType))
+	lexer.Add([]byte(`fromyaml`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: YamlInputFormat}))
+	lexer.Add([]byte(`fromjson`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: YamlInputFormat}))
+	lexer.Add([]byte(`fromxml`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: XmlInputFormat}))
 
-	lexer.Add([]byte(`from_yaml`), opToken(decodeOpType))
-	lexer.Add([]byte(`from_json`), opToken(decodeOpType))
+	lexer.Add([]byte(`from_yaml`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: YamlInputFormat}))
+	lexer.Add([]byte(`from_json`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: YamlInputFormat}))
+	lexer.Add([]byte(`from_xml`), opTokenWithPrefs(decodeOpType, nil, decoderPreferences{format: XmlInputFormat}))
 
 	lexer.Add([]byte(`sortKeys`), opToken(sortKeysOpType))
 	lexer.Add([]byte(`sort_keys`), opToken(sortKeysOpType))

pkg/yqlib/operator_encoder_decoder.go

@@ -68,9 +68,23 @@ func encodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 	return context.ChildContext(results), nil
 }
 
+type decoderPreferences struct {
+	format InputFormat
+}
+
 /* takes a string and decodes it back into an object */
 func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
 
+	preferences := expressionNode.Operation.Preferences.(decoderPreferences)
+
+	var decoder Decoder
+	switch preferences.format {
+	case YamlInputFormat:
+		decoder = NewYamlDecoder()
+	case XmlInputFormat:
+		decoder = NewXmlDecoder("+a", "+content")
+	}
+
 	var results = list.New()
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
@@ -79,7 +93,9 @@ func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 
 		var dataBucket yaml.Node
 		log.Debugf("got: [%v]", candidate.Node.Value)
-		decoder := yaml.NewDecoder(strings.NewReader(unwrapDoc(candidate.Node).Value))
+
+		decoder.Init(strings.NewReader(unwrapDoc(candidate.Node).Value))
+
 		errorReading := decoder.Decode(&dataBucket)
 		if errorReading != nil {
 			return Context{}, errorReading

pkg/yqlib/operator_encoder_decoder_test.go

@@ -168,6 +168,14 @@ var encoderDecoderOperatorScenarios = []expressionScenario{
 			"D0, P[], (doc)::a: \"foo:\\n  a: frog\"\n",
 		},
 	},
+	{
+		description: "Decode a xml encoded string",
+		document:    `a: "<foo>bar</foo>"`,
+		expression:  `.b = (.a | from_xml)`,
+		expected: []string{
+			"D0, P[], (doc)::a: \"<foo>bar</foo>\"\nb:\n    foo: bar\n",
+		},
+	},
 }
 
 func TestEncoderDecoderOperatorScenarios(t *testing.T) {

scripts/copy-docs.sh

@@ -1,4 +1,5 @@
 #!/bin/bash
 
 cp how-it-works.md ../yq-gitbook/.
-cp pkg/yqlib/doc/*.md ../yq-gitbook/operators/.
+cp pkg/yqlib/doc/operators/*.md ../yq-gitbook/operators/.
+cp pkg/yqlib/doc/usage/*.md ../yq-gitbook/usage/.