Env Ops!

pkg/yqlib/doc/Env Variable Operators.md

@@ -1,21 +1,76 @@
 
+## Read string environment variable
+Running
+```bash
+myenv="cat meow" yq eval --null-input '.a = env(myenv)'
+```
+will output
+```yaml
+a: cat meow
+```
+
+## Read boolean environment variable
+Running
+```bash
+myenv="true" yq eval --null-input '.a = env(myenv)'
+```
+will output
+```yaml
+a: true
+```
+
+## Read numeric environment variable
+Running
+```bash
+myenv="12" yq eval --null-input '.a = env(myenv)'
+```
+will output
+```yaml
+a: 12
+```
+
+## Read yaml environment variable
+Running
+```bash
+myenv="{b: fish}" yq eval --null-input '.a = env(myenv)'
+```
+will output
+```yaml
+a: {b: fish}
+```
+
 ## Read boolean environment variable as a string
 Running
 ```bash
-myenv="true" yq eval --null-input 'strenv(myenv)'
+myenv="true" yq eval --null-input '.a = strenv(myenv)'
 ```
 will output
 ```yaml
-12
+a: "true"
 ```
 
 ## Read numeric environment variable as a string
 Running
 ```bash
-myenv="12" yq eval --null-input 'strenv(myenv)'
+myenv="12" yq eval --null-input '.a = strenv(myenv)'
 ```
 will output
 ```yaml
-12
+a: "12"
+```
+
+## Dynamic key lookup with environment variable
+Given a sample.yml file of:
+```yaml
+cat: meow
+dog: woof
+```
+then
+```bash
+myenv="cat" yq eval '.[env(myenv)]' sample.yml
+```
+will output
+```yaml
+meow
 ```
 

pkg/yqlib/doc/Traverse.md

@@ -48,6 +48,24 @@ will output
 frog
 ```
 
+## Dynamic keys
+Expressions within [] can be used to dynamically lookup / calculate keys
+
+Given a sample.yml file of:
+```yaml
+b: apple
+apple: crispy yum
+banana: soft yum
+```
+then
+```bash
+yq eval '.[.b]' sample.yml
+```
+will output
+```yaml
+crispy yum
+```
+
 ## Children don't exist
 Nodes are added dynamically while traversing
 

pkg/yqlib/operator_env.go

@@ -3,13 +3,14 @@ package yqlib
 import (
 	"container/list"
 	"os"
+	"strings"
 
 	yaml "gopkg.in/yaml.v3"
 )
 
-// type EnvOpPreferences struct {
-// 	StringValue bool
-// }
+type EnvOpPreferences struct {
+	StringValue bool
+}
 
 func EnvOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *PathTreeNode) (*list.List, error) {
 	envName := pathNode.Operation.CandidateNode.Node.Value
@@ -17,15 +18,34 @@ func EnvOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *PathTreeNo
 
 	rawValue := os.Getenv(envName)
 
+	preferences := pathNode.Operation.Preferences.(*EnvOpPreferences)
+
+	var node *yaml.Node
+	if preferences.StringValue {
+		node = &yaml.Node{
+			Kind:  yaml.ScalarNode,
+			Tag:   "!!str",
+			Value: rawValue,
+		}
+	} else {
+		var dataBucket yaml.Node
+		decoder := yaml.NewDecoder(strings.NewReader(rawValue))
+		errorReading := decoder.Decode(&dataBucket)
+		if errorReading != nil {
+			return nil, errorReading
+		}
+		//first node is a doc
+		node = UnwrapDoc(&dataBucket)
+	}
+	log.Debug("ENV tag", node.Tag)
+	log.Debug("ENV value", node.Value)
+	log.Debug("ENV Kind", node.Kind)
+
 	target := &CandidateNode{
 		Path:     make([]interface{}, 0),
 		Document: 0,
 		Filename: "",
-		Node: &yaml.Node{
-			Kind:  yaml.ScalarNode,
-			Tag:   "!!str",
-			Value: rawValue,
-		},
+		Node:     node,
 	}
 
 	return nodeToMap(target), nil

pkg/yqlib/operator_env_test.go

@@ -5,20 +5,61 @@ import (
 )
 
 var envOperatorScenarios = []expressionScenario{
+	{
+		description:         "Read string environment variable",
+		environmentVariable: "cat meow",
+		expression:          `.a = env(myenv)`,
+		expected: []string{
+			"D0, P[], ()::a: cat meow\n",
+		},
+	},
+	{
+		description:         "Read boolean environment variable",
+		environmentVariable: "true",
+		expression:          `.a = env(myenv)`,
+		expected: []string{
+			"D0, P[], ()::a: true\n",
+		},
+	},
+	{
+		description:         "Read numeric environment variable",
+		environmentVariable: "12",
+		expression:          `.a = env(myenv)`,
+		expected: []string{
+			"D0, P[], ()::a: 12\n",
+		},
+	},
+	{
+		description:         "Read yaml environment variable",
+		environmentVariable: "{b: fish}",
+		expression:          `.a = env(myenv)`,
+		expected: []string{
+			"D0, P[], ()::a: {b: fish}\n",
+		},
+	},
 	{
 		description:         "Read boolean environment variable as a string",
 		environmentVariable: "true",
-		expression:          `strenv(myenv)`,
+		expression:          `.a = strenv(myenv)`,
 		expected: []string{
-			"D0, P[], (!!str)::\"true\"\n",
+			"D0, P[], ()::a: \"true\"\n",
 		},
 	},
 	{
 		description:         "Read numeric environment variable as a string",
 		environmentVariable: "12",
-		expression:          `strenv(myenv)`,
+		expression:          `.a = strenv(myenv)`,
 		expected: []string{
-			"D0, P[], (!!str)::\"12\"\n",
+			"D0, P[], ()::a: \"12\"\n",
+		},
+	},
+	{
+		description:         "Dynamic key lookup with environment variable",
+		environmentVariable: "cat",
+		document:            `{cat: meow, dog: woof}`,
+		expression:          `.[env(myenv)]`,
+		expected: []string{
+			"D0, P[cat], (!!str)::meow\n",
 		},
 	},
 }

pkg/yqlib/operator_traverse_path_test.go

@@ -54,6 +54,15 @@ var traversePathOperatorScenarios = []expressionScenario{
 			"D0, P[{}], (!!str)::frog\n",
 		},
 	},
+	{
+		description:    "Dynamic keys",
+		subdescription: `Expressions within [] can be used to dynamically lookup / calculate keys`,
+		document:       `{b: apple, apple: crispy yum, banana: soft yum}`,
+		expression:     `.[.b]`,
+		expected: []string{
+			"D0, P[apple], (!!str)::crispy yum\n",
+		},
+	},
 	{
 		description:    "Children don't exist",
 		subdescription: "Nodes are added dynamically while traversing",

pkg/yqlib/operators_test.go

@@ -170,8 +170,9 @@ func documentInput(w *bufio.Writer, s expressionScenario) (string, string) {
 
 	envCommand := ""
 
-		if(s.environmentVariable != "") {
+	if s.environmentVariable != "" {
 		envCommand = fmt.Sprintf("myenv=\"%v\" ", s.environmentVariable)
+		os.Setenv("myenv", s.environmentVariable)
 	}
 
 	if s.document != "" {
@@ -201,7 +202,6 @@ func documentInput(w *bufio.Writer, s expressionScenario) (string, string) {
 
 		writeOrPanic(w, "then\n")
 
-
 		if s.expression != "" {
 			writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v '%v' %v\n```\n", envCommand, command, s.expression, files))
 		} else {

pkg/yqlib/path_tokeniser.go

@@ -181,10 +181,12 @@ func stringValue(wrapped bool) lex.Action {
 func envOp(strenv bool) lex.Action {
 	return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
 		value := string(m.Bytes)
+		preferences := &EnvOpPreferences{}
 
 		if strenv {
 			// strenv( )
 			value = value[7 : len(value)-1]
+			preferences.StringValue = true
 		} else {
 			//env( )
 			value = value[4 : len(value)-1]
@@ -192,6 +194,7 @@ func envOp(strenv bool) lex.Action {
 
 		envOperation := CreateValueOperation(value, value)
 		envOperation.OperationType = EnvOp
+		envOperation.Preferences = preferences
 
 		return &Token{TokenType: OperationToken, Operation: envOperation}, nil
 	}
@@ -286,6 +289,7 @@ func initLexer() (*lex.Lexer, error) {
 
 	lexer.Add([]byte(`"[^"]*"`), stringValue(true))
 	lexer.Add([]byte(`strenv\([^\)]+\)`), envOp(true))
+	lexer.Add([]byte(`env\([^\)]+\)`), envOp(false))
 
 	lexer.Add([]byte(`\[`), literalToken(OpenCollect, false))
 	lexer.Add([]byte(`\]`), literalToken(CloseCollect, true))