Transforms API

Use the Core API to create, update, list, retrieve, and delete proxy request and response transforms.

Transforms are child resources of a proxy:

Request transforms run before RequestRocket sends the request to the target.
Response transforms run after payload filters and before the response is returned or recorded.

Core API requests use a user token in the raw Authorization header. Do not prefix the token with Bearer.

Endpoints

Request Transforms

Method	Endpoint	Description
GET	`/api/clients/{clientId}/proxies/{proxyId}/request-transforms`	List request transforms for a proxy
POST	`/api/clients/{clientId}/proxies/{proxyId}/request-transforms`	Create a request transform
GET	`/api/clients/{clientId}/proxies/{proxyId}/request-transforms/{transformId}`	Get a request transform with code
PUT	`/api/clients/{clientId}/proxies/{proxyId}/request-transforms/{transformId}`	Update a request transform
DELETE	`/api/clients/{clientId}/proxies/{proxyId}/request-transforms/{transformId}`	Delete a request transform

Response Transforms

Method	Endpoint	Description
GET	`/api/clients/{clientId}/proxies/{proxyId}/response-transforms`	List response transforms for a proxy
POST	`/api/clients/{clientId}/proxies/{proxyId}/response-transforms`	Create a response transform
GET	`/api/clients/{clientId}/proxies/{proxyId}/response-transforms/{transformId}`	Get a response transform with code
PUT	`/api/clients/{clientId}/proxies/{proxyId}/response-transforms/{transformId}`	Update a response transform
DELETE	`/api/clients/{clientId}/proxies/{proxyId}/response-transforms/{transformId}`	Delete a response transform

Shared Fields

Field	Type	Required On Create	Description
`transformMode`	string	Yes	`all` or `conditional`
`effect`	string	Conditional use	`include` or `exclude` when `transformMode` is `conditional`
`transformActive`	boolean	Yes	Whether the transform can run
`methods`	string array	No	HTTP methods to match
`path`	object	No	Path predicate
`query`	array	No	Query predicates
`headers`	array	No	Request header predicates
`body`	array	No	Request body predicates
`token`	array	No	JWT claim predicates
`variables`	array	No	Variables for predicate interpolation
`priority`	number	No	Higher priority wins when multiple transforms match
`notes`	string	No	Internal notes
`code`	string	Yes	TypeScript or JavaScript transform code, maximum 512 KB

Response transforms also support:

Field	Type	Description
`responseHeaders`	array	Response header predicates
`responseBody`	array	Response body predicates
`responseStatus`	array	Response status predicates

Code Requirements

code must contain a callable default export.

Request transform minimum:

export default async function transform(proxyContext, proxyRequest) {
  return proxyRequest;
}

Response transform minimum:

export default async function transform(proxyContext, proxyRequest, targetResponse) {
  return targetResponse;
}

The API rejects code that has no default export, uses imports or require, or references unsupported sandbox APIs such as process, fetch, globalThis, eval, or Function.

Create Request Transform

Request

POST /api/clients/{clientId}/proxies/{proxyId}/request-transforms HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}
Content-Type: application/json

{
  "transformMode": "all",
  "transformActive": true,
  "priority": 100,
  "notes": "Add source header for target API",
  "code": "export default async function transform(proxyContext, proxyRequest) { return { ...proxyRequest, headers: { ...proxyRequest.headers, \"x-source-system\": \"requestrocket\" } }; }"
}

Response

{
  "requestTransforms": [
    {
      "pKey": "proxy_789",
      "sKey": "550e8400-e29b-41d4-a716-446655440000",
      "clientId": "client_456",
      "userId": "user_123",
      "parentId": "proxy_789",
      "transformRegion": "ap-southeast-2",
      "transformMode": "all",
      "effect": null,
      "transformActive": true,
      "methods": null,
      "path": null,
      "query": null,
      "headers": null,
      "body": null,
      "token": null,
      "variables": null,
      "priority": 100,
      "notes": "Add source header for target API",
      "createdAt": "2026-07-01T00:00:00.000Z",
      "updatedAt": "2026-07-01T00:00:00.000Z",
      "code": "export default async function transform(proxyContext, proxyRequest) { return { ...proxyRequest, headers: { ...proxyRequest.headers, \"x-source-system\": \"requestrocket\" } }; }"
    }
  ],
  "message": "Success"
}

Example

curl -X POST "https://api.requestrocket.com/api/clients/${CLIENT_ID}/proxies/${PROXY_ID}/request-transforms" \
  -H "Authorization: ${USER_TOKEN}" \
  -H "Content-Type: application/json" \
  -d '{
    "transformMode": "all",
    "transformActive": true,
    "priority": 100,
    "code": "export default async function transform(proxyContext, proxyRequest) { return proxyRequest; }"
  }'

const response = await fetch(
  `https://api.requestrocket.com/api/clients/${clientId}/proxies/${proxyId}/request-transforms`,
  {
    method: 'POST',
    headers: {
      Authorization: process.env.USER_TOKEN,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      transformMode: 'all',
      transformActive: true,
      priority: 100,
      code: 'export default async function transform(proxyContext, proxyRequest) { return proxyRequest; }'
    })
  }
);

const data = await response.json();
console.log(data.requestTransforms[0]);

Create Response Transform

Request

POST /api/clients/{clientId}/proxies/{proxyId}/response-transforms HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}
Content-Type: application/json

{
  "transformMode": "conditional",
  "effect": "include",
  "transformActive": true,
  "responseStatus": [
    {
      "operator": "equals",
      "value": 200
    }
  ],
  "priority": 100,
  "notes": "Normalize successful customer responses",
  "code": "export default async function transform(proxyContext, proxyRequest, targetResponse) { return { ...targetResponse, data: { id: targetResponse.data?.customer_id, name: targetResponse.data?.display_name } }; }"
}

Response

{
  "responseTransforms": [
    {
      "pKey": "proxy_789",
      "sKey": "550e8400-e29b-41d4-a716-446655440001",
      "clientId": "client_456",
      "userId": "user_123",
      "parentId": "proxy_789",
      "transformRegion": "ap-southeast-2",
      "transformMode": "conditional",
      "effect": "include",
      "transformActive": true,
      "methods": null,
      "path": null,
      "query": null,
      "headers": null,
      "body": null,
      "token": null,
      "responseHeaders": null,
      "responseBody": null,
      "responseStatus": [
        {
          "operator": "equals",
          "value": 200
        }
      ],
      "variables": null,
      "priority": 100,
      "notes": "Normalize successful customer responses",
      "createdAt": "2026-07-01T00:00:00.000Z",
      "updatedAt": "2026-07-01T00:00:00.000Z",
      "code": "export default async function transform(proxyContext, proxyRequest, targetResponse) { return { ...targetResponse, data: { id: targetResponse.data?.customer_id, name: targetResponse.data?.display_name } }; }"
    }
  ],
  "message": "Success"
}

responseStatus, responseHeaders, and responseBody only apply to response transforms. Request transforms are matched before the target request is sent.

List Transforms

GET /api/clients/{clientId}/proxies/{proxyId}/request-transforms HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}

List responses include transform metadata. Use the single-resource GET endpoint when you need the stored code.

{
  "requestTransforms": [
    {
      "pKey": "proxy_789",
      "sKey": "550e8400-e29b-41d4-a716-446655440000",
      "transformMode": "all",
      "transformActive": true,
      "priority": 100,
      "notes": "Add source header for target API"
    }
  ],
  "message": "Success"
}

Get Transform

GET /api/clients/{clientId}/proxies/{proxyId}/request-transforms/{transformId} HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}

Single-transform responses include code.

Update Transform

Update accepts partial fields. Include code only when changing the transform code.

PUT /api/clients/{clientId}/proxies/{proxyId}/response-transforms/{transformId} HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}
Content-Type: application/json

{
  "transformActive": false,
  "notes": "Temporarily disabled while target payload changes"
}

Successful updates return the updated transform, including the current stored code.

Delete Transform

DELETE /api/clients/{clientId}/proxies/{proxyId}/request-transforms/{transformId} HTTP/1.1
Host: api.requestrocket.com
Authorization: {user_token}

Delete removes the transform metadata and stored code. Deletion takes effect immediately.

Validation Errors

Create and update requests return 400 when the input fails schema validation or code validation.

Example code validation response:

{
  "message": "Transform code failed validation",
  "errors": [
    "request transform must export a default function or callable expression",
    "Imports are not supported in transforms"
  ]
}

Next Steps

Transforms Guide

Learn how transforms run and how to write safe transform code

Proxies API

Create and manage proxies

Payload Filters

Understand where response transforms run in the response pipeline

Transforms API

Transforms Guide

Proxies API

Payload Filters

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