Email Verification

A workflow that validates an email address submitted through a form.

Full source

# Email Verification Workflow
# Validates a submitted email address and returns the result.

config:
    name: "Email Verification"
    version: 1

services:
    EmailVerifier is an API at "https://verify.example.com/api"

workflow:
    trigger: when a form is submitted

    set email to signup.email
    log "Verifying email: {email}"

    verify email using EmailVerifier with address email

    if email is not empty:
        log "Email is valid"
        complete with status "verified" and email email
    otherwise:
        reject with "The email address could not be verified"

What this does

1. Extracts the email from the incoming form submission (signup.email)
2. Calls an external API to verify the email address
3. Checks the result — if the email is valid, completes with a success status
4. Rejects if the email could not be verified

Concepts demonstrated

• Service declaration — declaring an API with a base URL
• Variable assignment — set email to signup.email
• String interpolation — "Verifying email: {email}"
• Service calls with parameters — verify email using EmailVerifier with address email
• Conditional logic — if / otherwise
• Completion and rejection — complete with / reject with

Running it

# Test with mock services
flow test examples/email-verification.flow --dry-run --verbose

# Run with input
flow run examples/email-verification.flow \
  --mock \
  --input '{"signup": {"email": "alice@example.com"}}'

As a webhook

flow serve examples/email-verification.flow --mock

curl -X POST http://localhost:3000 \
  -H "Content-Type: application/json" \
  -d '{"signup": {"email": "alice@example.com"}}'