Retrieve feature flags with API

The Evaluation Server offers two APIs that allow you to retrieve feature flags for both client-side and server-side sdks, specific to the desired environment.

The differences between client side and server side SDKs are:

Client side SDK is for single user but Server side SDK is for multiple users
Client side SDK relies on the Evaluation Server to evaluate all the flags while Server side SDK evaluates the flags locally

ℹ️

Please note that you need to replace {Host} in the API requests with the appropriate host URL for your environment. {Host} can be the evaluation server host or the FeatBit Agent host, both of them provides the same API.

Client Side

For client-side requests, provide the client environment secret in the Authorization header.

Request

curl -X POST {Host}/api/public/sdk/client/latest-all \
-H 'Content-Type: application/json' \
-H 'Authorization: client-env-secret' \
-d '{
    "keyId": "bot-id",
    "name": "bot",
    "customizedProperties": [
        {
            "name": "level",
            "value": "high"
        },
        {
            "name": "localtion",
            "value": "us"
        }
    ]
}'

Response

{
   "messageType":"data-sync",
   "data":{
      "eventType":"full",
      "userKeyId":"bot-id",
      "featureFlags":[
         {
            "id":"hello-world",
            "variation":"false",
            "variationType":"boolean",
            "variationId":"3f02a597-a150-4c3f-83b9-27a2de80c7dc",
            "matchReason":"flag disabled",
            "variationOptions":[
               {
                  "id":"fafb6319-9270-4a4b-b2c3-12d2be29e69a",
                  "value":"true"
               },
               {
                  "id":"3f02a597-a150-4c3f-83b9-27a2de80c7dc",
                  "value":"false"
               }
            ],
            "sendToExperiment":false,
            "timestamp":1712755780494
         }
      ]
   }
}

Server Side

For server-side requests, provide the server environment secret in the Authorization header.

Request

curl -H "Authorization: server-env-secret" {Host}/api/public/sdk/server/latest-all

Response

{
   "messageType":"data-sync",
   "data":{
      "eventType":"full",
      "featureFlags":[
         {
            "envId":"1331554d-98c4-41fe-ade4-68e6f5eeb54a",
            "name":"hello world",
            "key":"hello-world",
            "variationType":"boolean",
            "variations":[
               {
                  "id":"bbe8f444-090e-4a3b-99fa-b487bab424aa",
                  "value":"true"
               },
               {
                  "id":"cf8f9626-0d6f-4d05-a98f-8c3a50c85d0f",
                  "value":"false"
               }
            ],
            "targetUsers":[
               
            ],
            "rules":[
               
            ],
            "isEnabled":true,
            "disabledVariationId":"cf8f9626-0d6f-4d05-a98f-8c3a50c85d0f",
            "fallthrough":{
               "dispatchKey":null,
               "includedInExpt":true,
               "variations":[
                  {
                     "id":"bbe8f444-090e-4a3b-99fa-b487bab424aa",
                     "rollout":[
                        0,
                        1
                     ],
                     "exptRollout":1
                  }
               ]
            },
            "exptIncludeAllTargets":true,
            "tags":[
               
            ],
            "isArchived":false,
            "disabledVariation":{
               "id":"cf8f9626-0d6f-4d05-a98f-8c3a50c85d0f",
               "value":"false"
            },
            "creatorId":"b58fa8fd-eca2-460a-ab0f-e7758dbcec6a",
            "updatorId":"b58fa8fd-eca2-460a-ab0f-e7758dbcec6a",
            "createdAt":"2023-03-16T09:11:23.739Z",
            "updatedAt":"2023-03-16T09:11:26.0465535Z",
            "id":"4daca70f-86ae-4468-aee8-afc700977202"
         }
      ],
      "segments":[
         {
            "envId":"1331554d-98c4-41fe-ade4-68e6f5eeb54a",
            "name":"beta users",
            "description":"this is a segment for beta users",
            "included":[
               
            ],
            "excluded":[
               
            ],
            "rules":[
               
            ],
            "isArchived":false,
            "createdAt":"2023-03-16T09:18:21.1317917Z",
            "updatedAt":"2023-03-16T09:18:21.1317248Z",
            "id":"b2b91bbe-5d54-4d8a-882f-afc700995b23"
         }
      ]
   }
}

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