API ReferenceFlag Evaluation APIOfrep

Evaluate all flags

Evaluate all feature flags for the given context.

ETag Caching

This endpoint supports ETag-based caching to reduce bandwidth and improve performance for polling clients.

How it works

First request: Call without If-None-Match header. Response includes an ETag header.
Subsequent requests: Include the If-None-Match header with the previous ETag value.
If flags unchanged: Server returns 304 Not Modified with no body.
If flags changed: Server returns 200 OK with new flag values and a new ETag.

Example flow

# First request
POST /ofrep/v1/evaluate/flags
X-API-Key: your-api-key

Response: 200 OK
ETag: "abc123"
{ "flags": [...] }

# Subsequent request with ETag
POST /ofrep/v1/evaluate/flags
X-API-Key: your-api-key
If-None-Match: "abc123"

Response: 304 Not Modified (no body)

When to use

Use ETag caching when polling for flag updates. For real-time updates, consider using the SSE endpoint at /api/v1/flags/events instead.

Header Parameters

X-API-Key*string

API key for authentication

If-None-Match?string

ETag from a previous response. If the flag configuration hasn't changed, the server returns 304 Not Modified.

X-Flipswitch-SDK?string

X-Flipswitch-Runtime?string

X-Flipswitch-OS?string

X-Flipswitch-Features?string

Request Body

application/json

Evaluation request with context

context*

Response Body

`application/json`

`application/json`

`application/json`

curl -X POST "https://loading/ofrep/v1/evaluate/flags" \  -H "X-API-Key: string" \  -H "Content-Type: application/json" \  -d '{    "context": {      "targetingKey": "string"    }  }'

{
  "flags": [
    {
      "result": {
        "key": "string",
        "errorCode": "string",
        "errorDetails": "string"
      }
    }
  ],
  "metadata": {
    "property1": null,
    "property2": null
  }
}

Empty

{
  "errorCode": "string",
  "errorDetails": "string"
}

Empty

Empty

{
  "errorCode": "string",
  "errorDetails": "string"
}

Subscribe to flag change events

Server-Sent Events (SSE) endpoint for real-time flag change notifications. ## Overview This endpoint establishes a long-lived SSE connection that streams flag change events in real-time. Use this to keep your application's flag values synchronized without polling. ## Connection Behavior - **Long-lived connection**: The connection remains open indefinitely until closed by the client - **Automatic filtering**: Events are filtered to only include changes for the environment associated with your API key - **Heartbeat**: A heartbeat event is sent every 15 seconds to keep the connection alive and detect stale connections ## Event Types ### `flag-updated` Event Sent when a single flag is created, updated, or deleted. ``` event: flag-updated data: {"flagKey":"my-feature","timestamp":"2024-01-21T10:30:45.123Z"} id: 1705844445123 ``` | Field | Type | Description | |-------|------|-------------| | `flagKey` | string | The key of the flag that changed. | | `timestamp` | string | ISO 8601 timestamp of when the change occurred. | | `id` | string | Event ID in epoch milliseconds. Use for client-side ordering and deduplication. | ### `config-updated` Event Sent when configuration changed that may affect multiple flags. Clients should re-evaluate all flags. ``` event: config-updated data: {"reason":"segment-modified","timestamp":"2024-01-21T10:30:45.123Z"} id: 1705844445123 ``` | Field | Type | Description | |-------|------|-------------| | `reason` | string | Why the configuration update occurred. | | `timestamp` | string | ISO 8601 timestamp of when the change occurred. | | `id` | string | Event ID in epoch milliseconds. Use for client-side ordering and deduplication. | **Possible `reason` values:** - `segment-modified` - A segment rule was created, updated, or deleted - `api-key-rotated` - API key was regenerated ### `heartbeat` Event Sent every 15 seconds to keep the connection alive. ``` event: heartbeat data: {} ``` No action required from clients. This event helps detect stale connections and prevents proxy timeouts. ## curl (Testing) ```bash curl -N -H "X-API-Key: your-api-key" \ https://your-server/api/v1/flags/events ```

Evaluate single flag

Evaluate a single feature flag for the given context