Best Practices for Using Email in FME Flow

Introduction

FME Flow provides multiple mechanisms for sending and receiving email, and for monitoring platform activity through email notifications. Each mechanism involves different components and configurations. Understanding which mechanism applies to a given scenario helps avoid common misconfigurations. This article covers three areas: receiving email to trigger workflows, sending email from workspaces and automations, and using email to monitor platform-level events such as job status and system events. 

For Microsoft Exchange Online, OAuth 2.0 (Modern Authentication) is required. See Connect to Microsoft Exchange Online using OAuth 2.0 for configuration steps. 

Receiving Email in FME Flow

An incoming email can trigger a workflow in FME Flow. How this is configured depends on whether the workflow is built in Automations or the Notification Service. For new implementations, the Automation Triggers are preferred. You can use the Notification Service publications only when working within an existing topic-based workflow.

Both Automation and the Notification Service support Simple Mail Transfer Protocol (SMTP) and Internet Message Access Protocol (IMAP). See the documentation below for detailed information and configuration steps.

To choose between SMTP and IMAP, consider the following:

• IMAP is a pull-based mechanism. The Email (IMAP) Trigger polls an existing IMAP server (such as imap.gmail.com) for messages. As long as IMAP access is enabled on the email account, no additional configuration is needed. However, because polling is conducted at intervals, FME Flow may not receive email messages as immediately as those sent over SMTP.
• SMTP is a push-based mechanism. FME Flow acts as its own lightweight SMTP server and receives emails directly, rather than polling for them. As a result, emails may be sent to FME Flow topics (and their subscribed workspaces) more immediately than emails delivered over IMAP.
• SMTP functions only on an instance of FME Flow with a valid DNS record (i.e., the server is accessible over the internet). If your FME Flow instance runs locally or on an intranet, you must use IMAP.
• SMTP is not supported in a fault-tolerant FME Flow installation.

In general, we recommend using IMAP Trigger in Automation if there is no requirement for immediate polls to the email server. IMAP has fewer restrictions on the DNS record and the deployment type of FME Flow.

Sending Email from FME Flow 

FME Flow provides three methods for sending email: the Emailer transformer, the Email External Action in Automations, and the legacy Email Subscriber in the Notification Service. Each serves a different purpose and applies in a different context.

Emailer Transformer

The Emailer is a workspace-level transformer that runs within FME Form or FME Flow. Because it is package-based, it can be updated independently of an FME release. It is useful when email providers such as Gmail or Microsoft change their authentication requirements.

Key Characteristics:

• Sends email per feature, as features flow through the transformer. An email can be sent mid-translation, before the workspace finishes.
• Supports Input-driven mode (one email per incoming feature) and Run Once mode (a single email regardless of the number of features).
• Keeps email logic self-contained within the workspace, making it portable between FME Form and FME Flow.
• Attribute values can be passed directly into the email body (e.g., embedding an HTML report generated by the HTMLReportGenerator).
• Supports saving emailer configuration as presets, which are useful when multiple workspaces share the same server settings.

When to Use

Workspaces where email is part of the data processing logic, or when the same workspace runs in both FME Form and FME Flow, and consistent behavior is required in both environments. Detailed information about the Emailer transformer and configuration steps can be found in the documentation here.

Email External Action (Automations)

The Email External Action is configured within an Automations workflow in the FME Flow Web UI. It delivers email via SMTP after upstream components in the workflow have completed.

Key Characteristics:

• Configured entirely in the Web UI. No workspace changes are required to update email settings.
• Can send an email without running any workspace, triggered by system events or external inputs.
• Email fires after the workspace completes. Can have access to job metadata such as job ID, status message, and submission/finish times 
• Provides built-in success and failure output ports for downstream automation logic.
• Supports configurable retry on failure.

When to use

Event-driven automation workflows, or scenarios where email configuration must be centralized and updated without modifying workspaces. Detailed information on the External Email Action can be found in the documentation here.

Email Subscriber (Legacy Notification Service)

The Email Subscriber is part of the Notification Service. It is configured through the Notifications page using a publisher/subscriber/topic model, rather than the Automations canvas. The Email Subscriber receives messages from topics and delivers emails via the SMTP protocol. 

Key characteristics:

• Publishers send content to a topic; subscribers listen to topics and deliver messages via a supported protocol, including email.
• Supports the Email Template Language for customizing message content with dynamic tags.

When to use

Environments with existing Notification Service configurations. See the documentation for the detailed information and configuration steps. For new implementations, the Email External Action in Automations is preferred. 

Monitoring FME Flow Using Email

FME Flow publishes content about significant activity and events, such as when a workspace run succeeds or fails, or when a repository is created. This content can trigger email notifications in two ways: by monitoring system events and by monitoring job events from topics.

Monitoring FME Flow System Events

FME Flow publishes content about significant platform events, such as repository creation and system backups. These events can be monitored in the following ways:

• On the System Events page. Use the Configuration tab to send emails when events occur and to enable or disable which events are monitored. Use the History tab to view a record of all enabled events.
• In an Automations workflow initiated by one or more FME Flow System Event triggers. For example, a workflow can notify recipients by email every time a repository is created or a system backup completes.

Note: System Email, configured under Admin > System Configuration > Network & Email, defines the SMTP server that FME Flow uses to send these platform-level notifications. This is a global, outbound email configuration. It is not specific to any automation or workspace. See System Email for configuration details.

Monitoring FME Flow Events from Topics

FME Flow publishes certain event content to pre-existing Notification Service topics. This content includes:

• When workspaces run from FME Flow succeed or fail.
• When a backup or restore operation succeeds or fails.
• When workspaces run to generate Dashboard statistics.

These topics can be used in the following ways:

• In an Automations workflow initiated by an FME Flow Topic trigger (Preferred). For example, a workflow can deliver an email whenever the JOBSUBMITTER_ASYNC_JOB_FAILURE topic is notified.
• In Subscriptions: FME Flow includes a set of pre-configured subscribers already subscribed to these topics. When fully configured, these subscribers can deliver content via email or other supported protocols.

Additional information and configuration steps can be found in the documentation here.