GitHub Actions Workflow Expression Regex for Go

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching github actions workflow expression, ported and verified for Go. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Go project — whether you're validating in a Gin handler, a gRPC service, or a command-line tool.

Go Implementation

// GitHub Actions Workflow Expression
// ReDoS-safe | RegexVault — Dev & Systems > Git

package validation

import "regexp"

var githubActionsWorkflowExpressionRe = regexp.MustCompile(`^\$\{\{\s+(?:github|env|vars|secrets|inputs|runner|job|steps|needs|matrix|strategy)(?:\.[a-zA-Z_][a-zA-Z0-9_\-]*)+\s+\}\}$`)

func ValidateGithubActionsWorkflowExpression(s string) bool {
    return githubActionsWorkflowExpressionRe.MatchString(s)
}

// Example
// fmt.Println(ValidateGithubActionsWorkflowExpression("${{ github.sha }}")) // true

Test Cases

When to use this pattern

This pattern is drawn from the Dev & Systems > Git category and carries a ReDoS-safe certification. That matters for Go developers because Go's RE2 engine is inherently safe from catastrophic backtracking, but this pattern has been additionally verified for correctness. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Requires at least two dot-separated components (context.property). Context names are lowercase in GitHub Actions. The i flag is not needed.