With the organization looking to build flexible and scalable integrations across the complete technology landscape, event-driven architecture has become an increasingly important component. When it comes to Salesforce, insight into the design of optimal solutions opens with the difference that exists between its Platform Events and Streaming mechanisms. Precisely, this detailed comparison enables the architect or developer to make informed decisions.
Understanding Event-Driven Architecture in Salesforce
Event-driven architecture provides a means for both low-latency production and consumption of events representing state changes. It provides near real-time updates without the publishers or subscribers having to be directly connected. Salesforce supports this architecture with a set of tools and patterns such as Platform Events and a number of Streaming APIs, depending on different use cases. Salesforce is one of the top CRM development company.
What Are Platform Events?
Platform Events are secure, scalable messages that contain custom event data. They are the central messaging mechanism in the Salesforce event-driven ecosystem.
Key Characteristics:
- User-defined event structures
- Support for both low-code and pro-code implementations
- Can be published through APIs, Apex, or Flow
- Consumed via Apex, APIs, Flow, or Lightning Web Components
- Payload limit is 1MB per message.
- Default retention period for high-volume events: 3 days (1 day for standard volume)
Publishing Methods:
- Declarative tools, such as Flow Builder
- Programmatic approaches using Apex triggers
- External systems via REST or SOAP APIs
- Pub/Sub API for modern implementations
Platform events support real-time and non-real-time publishing modes. Real-time events publish immediately during the transactions before the final commit, whereas non-real-time events publish only after the successful commit of transactions. Understanding these modes is crucial to avoiding the Platform Event Trap where improper usage leads to race conditions or infinite loops.
An Introduction to Streaming Events
Streaming Events in Salesforce is a group of technologies that allow real-time communication using a subscription model.
The Streaming Event Mechanisms:
Change Data Capture (CDC)
CDC publishes change events indicating changes to Salesforce records, consisting of:
- Creation of records
- Update to an existing record
- Deletion of a record
- Undeletion of a record
Technical Details:
- Predefined message format
- 3-day replay window
- 1 MB payload size limit
- Low-code or pro-code knowledge needed
- Can subscribe with Apex, APIs, or Lightning Web Components
PushTopic Events (Legacy)
PushTopic Events provide notifications for Salesforce data changes matching user-defined SOQL queries.
Characteristics:
- The subscription-based query model
- 1-day replay period
- 1 MB limit on payload
- User-defined structure via SOQL query
- -Salesforce continues to support, but doesn’t plan further investments
Generic Events (Legacy)
Specifications:
- 1-day replay period
- 3,000-character payload limit
- Flexible structure for custom use cases
- Published via APIs, consumed through APIs or LWC
- Legacy status with continued support but limited further development
Platform Events vs Streams: Critical Differences
| Feature | Platform Events | Change Data Capture | PushTopic Events | Generic Events |
| Data Source | Custom definitions | Salesforce record changes | Query-based record changes | Custom payloads |
| Replay Period | 3 days (high-volume) | 3 days | 1 day | 1 day |
| Payload Size | 1 MB | 1 MB | 1 MB | 3,000 characters |
| Structure | User-defined | Predefined | User-defined (SOQL) | User-defined |
| Skill Level | Low-code to Pro-code | Low-code to Pro-code | Hybrid | Low-code to Pro-code |
| Future Investment | Active development | Active development | Legacy (limited) | Legacy (limited) |
| Publishing | APIs, Apex, Flow | Automatic on record changes | Automatic on query match | APIs only |
Pub/Sub API: The Recommended Approach
Salesforce recommends that, for any future publish/subscribe pattern, one should use the Pub/Sub API instead of building custom event handlers with other APIs.
Key Advantages:
- Single subscription framework for Platform Events, CDC, and Real-Time Event Monitoring
- Better performance and scalablity
- New protocol leveraging gRPC
- Replay capabilty for 3 days…
- Pro-code implementation for the utmost flexibility
When possible, organizations should plan the migration of existing implementations using Streaming API or custom Apex services to Pub/Sub API.
Use Cases
1. Real-time data synchronization across systems
Use CDC to replicate all the changes-create, update, and delete events-to Salesforce database records to external databases, data warehouses, or analytics platforms. This ensures all your downstream systems have the most up-to-date information available, with no need for polling or batch jobs, to give you consistent customer data across your technology stack.
2. Custom Business Process Automation
Use Platform Events to trigger such complex, cross-system workflows. On closing any high-value opportunity, Salesforce would publish a platform event that would trigger multiple system actions, including provisioning on your ERP system, sending welcome emails through marketing automation, creating support tickets, and updating your billing system-all in near real-time through a decoupled architecture.
3. AWS Cloud Integration
Seamlessly integrate Salesforce into AWS services using Event Relays with Amazon EventBridge. In this case, when any events, either Platform Events or CDC in nature, happen from Salesforce, they will land in AWS to potentially trigger your Lambdas, update DynamoDB tables, and start step functions. This is very useful for organizations running hybrid Salesforce-AWS architectures.
4. Real-time notifications and alerts
Platform Events allow for the customization of notifications so that users or external systems can be informed about the most important business events, which do not exactly correspond to record changes. Examples would include inventory reaching reorder points, SLA breaches, fraud detection alerts, or custom approval workflows that need to notify multiple stakeholders across different platforms simultaneously.
Each use case leverages many key strengths of event-driven architecture, including decoupling systems, enabling real-time responsiveness, and scaling across the enterprise landscape with efficiency.
Migration Strategy
First, it’s essential for organizations already using point-to-point integrations to migrate these gradually:
Phase 1: Assessment
- Identify integrations that are business-critical
- Assess current integration patterns
- Document event volume and frequency
Phase 2: Prioritization
- Convert high-value integrations first
- Focus on systems supporting event-driven patterns.
- Plan workarounds for legacy systems
Phase 3: Implementation
- Deploy new event-driven integrations
- Performance Monitoring and Configuration Adjustments
- Gather feedback and iterate
Phase 4: Expansion
- Eventually port outstanding integrations
- Standardization of event structures across organizations
- Establish governance frameworks
Event Relays for AWS Integration
Event Relays allow Platform Events and Change Data Capture events to flow from Salesforce into Amazon EventBridge. This enables:
- Low-code integration with AWS services
- 3-day replay capability
- User-Defined Payload Structures
- 1 MB payload limits
Further, this will enrich the possibility for organizations to use AWS infrastructure in addition to Salesforce.
Conclusion
Decisions regarding Salesforce Platform Events or Streams will rely on business needs, existing infrastructure, and future scalability. New implementations should be first done with Platform Events, which best adapt to new implementations by allowing maximum flexibility due to custom structures supported and modern Pub/Sub API support. Change Data Capture provides automated tracking of changes to records, requiring minimal configuration. Legacy Streaming APIs remain supported but should not be chosen for new projects, including PushTopics and Generic Events. Success here means thorough assessment of use cases, adequate planning of payload structures, and paying attention to architecture best practices. All organizations should make the needed priority in adopting the Pub/Sub API in concert with a planned migration away from legacy streaming implementations to long-term maintainability and performance.
