/oci

OCI Events Service - Patterns Reference

Event-Driven Architecture Patterns

Pattern 1: Object Storage Upload → Function Processing

┌─────────────────┐
│ Object Storage  │
│  - User uploads │
│    file.csv     │
└────────┬────────┘
         │ Event: createObject
         ▼
┌─────────────────┐
│   Events Rule   │
│  Filter: .csv   │
└────────┬────────┘
         │ Invoke
         ▼
┌─────────────────┐
│   Function      │
│  - Parse CSV    │
│  - Store in DB  │
│  - Send email   │
└─────────────────┘

Event Filter:
{
  "eventType": "com.oraclecloud.objectstorage.createobject",
  "data": {
    "additionalDetails": {
      "eTag": "*"
    },
    "resourceName": "*.csv"
  }
}

Use case: Data ingestion pipeline, document processing

Pattern 2: Compute Instance Lifecycle → Compliance Check

┌──────────────────┐
│ Compute Instance │
│  - Terminated    │
│  - Created       │
└────────┬─────────┘
         │ Event: terminateInstance
         ▼
┌──────────────────┐
│   Events Rule    │
│  Filter: Prod    │
└────────┬─────────┘
         │ Notify
         ▼
┌──────────────────┐     ┌──────────────────┐
│   Notification   │────▶│   PagerDuty     │
│   Topic          │     │   (On-call)      │
└──────────────────┘     └──────────────────┘

Event Filter:
{
  "eventType": "com.oraclecloud.computeapi.terminateinstance",
  "data": {
    "compartmentName": "Prod"
  }
}

Use case: Security monitoring, audit trail, incident response

Pattern 3: Fan-Out (1 Event → Multiple Actions)

┌─────────────────┐
│  Database       │
│  - Stopped      │
└────────┬────────┘
         │ Event: stopAutonomousDatabase
         ▼
┌─────────────────────────────────────┐
│   Events Rule                       │
│  Actions:                           │
│   1. Notification → Email SRE      │
│   2. Function → Log to Splunk      │
│   3. Streaming → Analytics         │
└─────────────────────────────────────┘

Use case: Multi-channel alerting, compliance logging, analytics
Max actions: 5 per rule

Pattern 4: Event Chaining (Event → Function → Event)

┌──────────────┐
│ IAM Policy   │
│  - Changed   │
└──────┬───────┘
       │ Event 1
       ▼
┌──────────────┐
│ Function 1   │
│ - Audit log  │
│ - Create     │
│   ticket     │
└──────┬───────┘
       │ Custom Event
       ▼
┌──────────────┐
│ Function 2   │
│ - Compliance │
│   check      │
└──────────────┘

Implementation: Functions can emit custom events using Events API
Use case: Complex workflows, approval chains

Event Filter Syntax Decision Tree

"How should I filter events?"
│
├─ Filter by event type only (all occurrences)?
│   └─ Simple filter
│       {
│         "eventType": "com.oraclecloud.computeapi.launchinstance"
│       }
│
├─ Filter by compartment or tag?
│   └─ Compartment filter
│       {
│         "eventType": "com.oraclecloud.computeapi.launchinstance",
│         "data": {
│           "compartmentName": "Prod"
│         }
│       }
│
├─ Filter by resource attribute (name pattern)?
│   └─ Attribute filter
│       {
│         "eventType": "com.oraclecloud.objectstorage.createobject",
│         "data": {
│           "resourceName": "*.pdf"
│         }
│       }
│
├─ Filter by multiple event types?
│   └─ Array of event types
│       {
│         "eventType": [
│           "com.oraclecloud.computeapi.launchinstance",
│           "com.oraclecloud.computeapi.terminateinstance"
│         ]
│       }
│
└─ Complex logic (AND/OR conditions)?
    └─ Use Cloud Events JSONPath
        {
          "eventType": "com.oraclecloud.computeapi.*",
          "data": {
            "freeformTags": {
              "Environment": "Prod"
            },
            "definedTags": {
              "Operations.CostCenter": "Engineering"
            }
          }
        }

Common Event Types by Service

Compute (com.oraclecloud.computeapi.*):
├─ launchinstance              # Instance created
├─ terminateinstance           # Instance deleted
├─ instanceaction              # Reboot, stop, start
├─ changeinstanceshape         # Shape changed (resize)
└─ attachvnic                  # Network interface attached

Database (com.oraclecloud.databaseservice.*):
├─ createautonomousdatabase    # ADB created
├─ stopautonomousdatabase      # ADB stopped
├─ startautonomousdatabase     # ADB started
├─ deleteautonomousdatabase    # ADB deleted
└─ updateautonomousdatabase    # ADB scaled/modified

Object Storage (com.oraclecloud.objectstorage.*):
├─ createobject                # File uploaded
├─ deleteobject                # File deleted
├─ updateobject                # File modified
└─ createbucket                # Bucket created

IAM (com.oraclecloud.identityControlPlane.*):
├─ CreateUser                  # User added
├─ UpdateUser                  # User modified
├─ CreatePolicy                # Policy created
├─ UpdatePolicy                # Policy changed
└─ DeleteUser                  # User removed

VCN (com.oraclecloud.virtualnetwork.*):
├─ CreateVcn                   # VCN created
├─ DeleteVcn                   # VCN deleted
├─ CreateSubnet                # Subnet created
├─ CreateSecurityList          # Security list created
└─ CreateNetworkSecurityGroup  # NSG created

Not a complete list. Look up event types in the Console rule editor or the
"Services that Produce Events" docs page (there is no CLI listing command).

Action Types and Use Cases

Check the Oracle price list for Notifications, Functions and Streaming pricing before estimating cost.

Choosing Action Type:

• 1-10 events/minute → ONS (notifications)
• 10-1000 events/minute → FAAS (processing)
• >1000 events/minute → OSS (streaming buffer)