feature: Add support for github action variables (#1833)

* feature: Add support for github action variables

* add --var flag for github variables

* unitests: Updated unittests to cover vars context.

* Remove syntax extension for vars and correct unit tests

* Update pkg/runner/expression.go

Co-authored-by: ChristopherHX <christopher.homberger@web.de>

---------

Co-authored-by: kuanyong-wong-partior <kuanyong.wong@partior.com>
Co-authored-by: ChristopherHX <christopher.homberger@web.de>

pkg/exprparser/interpreter.go

@@ -19,6 +19,7 @@ type EvaluationEnvironment struct {
 	Steps    map[string]*model.StepResult
 	Runner   map[string]interface{}
 	Secrets  map[string]string
+	Vars     map[string]string
 	Strategy map[string]interface{}
 	Matrix   map[string]interface{}
 	Needs    map[string]Needs
@@ -148,6 +149,7 @@ func (impl *interperterImpl) evaluateNode(exprNode actionlint.ExprNode) (interfa
 	}
 }
 
+// nolint:gocyclo
 func (impl *interperterImpl) evaluateVariable(variableNode *actionlint.VariableNode) (interface{}, error) {
 	switch strings.ToLower(variableNode.Name) {
 	case "github":
@@ -167,6 +169,8 @@ func (impl *interperterImpl) evaluateVariable(variableNode *actionlint.VariableN
 		return impl.env.Runner, nil
 	case "secrets":
 		return impl.env.Secrets, nil
+	case "vars":
+		return impl.env.Vars, nil
 	case "strategy":
 		return impl.env.Strategy, nil
 	case "matrix":

pkg/exprparser/interpreter_test.go

@@ -557,6 +557,7 @@ func TestContexts(t *testing.T) {
 		// {"contains(steps.*.outputs.name, 'value')", true, "steps-context-array-outputs"},
 		{"runner.os", "Linux", "runner-context"},
 		{"secrets.name", "value", "secrets-context"},
+		{"vars.name", "value", "vars-context"},
 		{"strategy.fail-fast", true, "strategy-context"},
 		{"matrix.os", "Linux", "matrix-context"},
 		{"needs.job-id.outputs.output-name", "value", "needs-context"},
@@ -593,6 +594,9 @@ func TestContexts(t *testing.T) {
 		Secrets: map[string]string{
 			"name": "value",
 		},
+		Vars: map[string]string{
+			"name": "value",
+		},
 		Strategy: map[string]interface{}{
 			"fail-fast": true,
 		},

pkg/runner/expression.go

@@ -77,6 +77,7 @@ func (rc *RunContext) NewExpressionEvaluatorWithEnv(ctx context.Context, env map
 		// but required to interpolate/evaluate the step outputs on the job
 		Steps:    rc.getStepsContext(),
 		Secrets:  getWorkflowSecrets(ctx, rc),
+		Vars:     getWorkflowVars(ctx, rc),
 		Strategy: strategy,
 		Matrix:   rc.Matrix,
 		Needs:    using,
@@ -124,6 +125,7 @@ func (rc *RunContext) NewStepExpressionEvaluator(ctx context.Context, step step)
 		Job:      rc.getJobContext(),
 		Steps:    rc.getStepsContext(),
 		Secrets:  getWorkflowSecrets(ctx, rc),
+		Vars:     getWorkflowVars(ctx, rc),
 		Strategy: strategy,
 		Matrix:   rc.Matrix,
 		Needs:    using,
@@ -483,3 +485,7 @@ func getWorkflowSecrets(ctx context.Context, rc *RunContext) map[string]string {
 
 	return rc.Config.Secrets
 }
+
+func getWorkflowVars(ctx context.Context, rc *RunContext) map[string]string {
+	return rc.Config.Vars
+}

pkg/runner/expression_test.go

@@ -28,6 +28,9 @@ func createRunContext(t *testing.T) *RunContext {
 			Secrets: map[string]string{
 				"CASE_INSENSITIVE_SECRET": "value",
 			},
+			Vars: map[string]string{
+				"CASE_INSENSITIVE_VAR": "value",
+			},
 		},
 		Env: map[string]string{
 			"key": "value",
@@ -122,6 +125,8 @@ func TestEvaluateRunContext(t *testing.T) {
 		{"env.key", "value", ""},
 		{"secrets.CASE_INSENSITIVE_SECRET", "value", ""},
 		{"secrets.case_insensitive_secret", "value", ""},
+		{"vars.CASE_INSENSITIVE_VAR", "value", ""},
+		{"vars.case_insensitive_var", "value", ""},
 		{"format('{{0}}', 'test')", "{0}", ""},
 		{"format('{{{0}}}', 'test')", "{test}", ""},
 		{"format('}}')", "}", ""},
@@ -195,6 +200,9 @@ func TestInterpolate(t *testing.T) {
 			Secrets: map[string]string{
 				"CASE_INSENSITIVE_SECRET": "value",
 			},
+			Vars: map[string]string{
+				"CASE_INSENSITIVE_VAR": "value",
+			},
 		},
 		Env: map[string]string{
 			"KEYWITHNOTHING":       "valuewithnothing",
@@ -229,6 +237,8 @@ func TestInterpolate(t *testing.T) {
 		{" ${{ env.KEY_WITH_UNDERSCORES }} ", " value_with_underscores "},
 		{"${{ secrets.CASE_INSENSITIVE_SECRET }}", "value"},
 		{"${{ secrets.case_insensitive_secret }}", "value"},
+		{"${{ vars.CASE_INSENSITIVE_VAR }}", "value"},
+		{"${{ vars.case_insensitive_var }}", "value"},
 		{"${{ env.UNKNOWN }}", ""},
 		{"${{ env.SOMETHING_TRUE }}", "true"},
 		{"${{ env.SOMETHING_FALSE }}", "false"},

pkg/runner/runner.go

@@ -34,6 +34,7 @@ type Config struct {
 	Env                                map[string]string          // env for containers
 	Inputs                             map[string]string          // manually passed action inputs
 	Secrets                            map[string]string          // list of secrets
+	Vars                               map[string]string          // list of vars
 	Token                              string                     // GitHub token
 	InsecureSecrets                    bool                       // switch hiding output when printing to terminal
 	Platforms                          map[string]string          // list of platforms