Flow Engine v1.0

Part of CloudWizard Email Suite

Flow Engine runs timed, multi-step email sequences — welcome series, onboarding drips, nurture flows — triggered either automatically when a subscriber confirms onto an Audience Manager list, or manually. A cron job checks every few minutes for enrollments due to receive their next step. It sends independently, with its own bundled mailer — Mail Engine is an optional enhancement, not a requirement.

Requirements

Step 1 — Install the Controller

Flow Engine runs inside the CloudWizard Controller. The controller handles authentication, shared database config, and module detection. Install it first.

public_html/CW/
  bootstrap.php
  config_path.php
  admin/
    index.php
    login.php
    logout.php
    settings.php
    setup.php
    style.css
    ...

Step 2 — Install Flow Engine

public_html/CW/FlowEngine/
  module.php
  bootstrap.php
  cron.php
  click.php               ← public endpoint, click tracking
  track_open.php          ← public endpoint, open tracking
  admin/
    _bootstrap.php
    index.php              ← Overview
    flows.php              ← Flow list
    flow_edit.php           ← Create/edit a flow and its steps
    enrollments.php
    step_preview.php
    step_preview_post.php

Step 3 — Activate your license

Step 4 — Set up the cron job

Nothing sends without this. Flow Engine's cron.php checks for enrollments due their next step and enrolls newly-confirmed subscribers into signup-triggered flows. Open Flow Engine → Overview for the exact command generated for your install:

Add it under Virtualmin → Scheduled Cron Jobs, running every 5-15 minutes — more frequent than that gains little, since step delays are rarely shorter.

Overview

Flow Engine → Overview is the landing page: active flows, active/completed/failed enrollment counts, total sent, cron status, and the cron setup block above.

Flows

Flow Engine → Flows lists every flow with its trigger type, step count, active/completed enrollment counts, and status. Click + New flow to create one:

Pause/Activate toggles a flow without deleting anything. Delete removes the flow along with every step and enrollment — this cannot be undone.

Steps & the step editor

Once a flow is saved, add steps with + Add step. Each step is one email in the sequence:

When a template is selected, it's merged in using the same placeholders Mail Engine templates use: {{preheader}} {{headline}} {{message}} {{tracker}} {{unsubscribe}} {{sender_name}} {{cta_url}} {{cta_text}} — the older square-bracket form works too, for templates built before this naming existed.

Use the ↑/↓ arrows in the steps table to reorder — delays are always relative to the step before, so reordering changes actual send timing, not just display order.

Preview & test send

While editing an existing step, Preview → saves your current edits and opens a modal showing the step rendered with its template applied (if one is selected). Send test reveals a small inline form to send that exact step to one address immediately, using Flow Engine's own mailer — useful for checking how it actually looks in an inbox before it goes live in the sequence.

Enrollments

Click Subscribers on any flow in the Flows list to see everyone enrolled in it — their current step, status (active/completed/failed), and next scheduled send time.

Running without Mail Engine

Flow Engine ships its own copy of PHPMailer and sends every step independently — it does not require Mail Engine to be installed. The only thing Mail Engine adds is templates: without it, the Template field in the step editor is simply unavailable, and steps send as plain HTML with no template merge.

Running without Audience Manager

Flow Engine runs standalone without Audience Manager too, with one real limit: since a signup-triggered flow is inherently about matching a confirmed list signup to a flow, that trigger type genuinely needs Audience Manager's subscriber/list data to work at all. Without Audience Manager:

• Signup-triggered flows never auto-enroll anyone — there's no signup event to trigger from. Manual enrollment flows are unaffected.
• The AM List and Exit list fields on a flow simply don't appear.
• The Enrollments page still works, just without a subscriber's name — only email, step, and status are shown.

Security

• Always use HTTPS. Enrollment and subscriber data should never travel over plain HTTP.
• The cron URL contains a secret key — don't share it publicly. The key is only checked for the URL-based option; running the script directly on the server requires no key, since shell access is already a higher trust level.
• Restrict admin access by IP if possible, in Nginx:
  

  allow 1.2.3.4;
  deny all;

Troubleshooting

CloudWizard Email Suite — Flow Engine v1.0
cloudwizard.eu — support@cloudwizard.eu