You're viewing **Apigee Edge** documentation. [Go to the **Apigee X** documentation](http://cloud.google.com/apigee/docs/api-platform/develop/enabling-streaming). info ## What you'll learn in this topic After reading this topic you will know: - What request and response streaming on Apigee Edge is - When to use request and response streaming - How to enable request and response streaming > [!NOTE] > **Sample:** If you'd like to jump directly to a code sample, see "[Related code samples](https://docs.apigee.com/api-platform/develop/enabling-streaming#RelatedCodeSamples)" for details. ## What is request and response streaming? By default, HTTP streaming is disabled and HTTP request and response payloads are written to a buffer in memory before they are processed by the API proxy pipeline. You can change this behavior by enabling streaming. With streaming enabled, request and response payloads are streamed without modification to the client app (for responses) and the target endpoint (for requests). ## When should I enable streaming? If your API proxy handles very large requests and/or responses (for size limits, see [What else should I know about streaming](https://docs.apigee.com/api-platform/develop/enabling-streaming#whatelseshouldiknowaboutstreaming) below), you may want to enable streaming. > [!NOTE] > **Note:** If your API requests or returns a large amount of data, you may see this HTTP error: > > ``` > {"fault":"{\"detail\":{\"errorcode\":\"protocol.http.TooBigBody\"},\"faultstring\":\"Body buffer overflow\"}"} > ``` > > If you see this error, we recommend that you enable streaming. If you continue to see the > error after you enable streaming, consider removing any policies that require access to the > request or response payload. For more information, see "Message payload size" in [Best > practices for API proxy design and development](https://docs.apigee.com/api-platform/fundamentals/best-practices-api-proxy-design-and-development). ## What else should I know about streaming? Message payload size is restricted to 10 MB in Edge Cloud and Private Cloud, even with streaming enabled. In non-streamed requests and responses, exceeding that size results in a `protocol.http.TooBigBody` error. > [!CAUTION] > While streaming can help you work around the > 10 MB request/response size limit enforced by the product, > Apigee doesn't recommend exceeding that limit when streaming and can't support issues that > arise as a result of exceeding that limit, such as performance issues, timeouts, and so on. > If you receive a timeout or gateway error, see [Error message reference](https://docs.apigee.com/api-platform/troubleshoot/apigee-edge-error-messages) for possible troubleshooting > steps. > > For payloads larger than 10 MB, Apigee recommends using a > signed URLs pattern within an Apigee JavaCallout, illustrated by the > [Edge Callout: Signed URL Generator](https://github.com/DinoChiesa/ApigeeEdge-Java-GoogleUrlSigner) example on GitHub. In Edge for Private Cloud deployments, you can modify the non-streamed request/response size limit. Be sure to test before deploying the change to production. - **For Edge for Private Cloud releases previous to 4.16.01:** On all Message Processors, edit the `http.properties` file to increase the limit in the `HTTPResponse.body.buffer.limit` parameter and then restart the Message Processor. - **For Edge for Private Cloud release 4.16.01 and later:** 1. Edit the file /\/apigee/customer/application/message-processor.properties. If that file does not exist, create it. 2. Set the conf_http_HTTPResponse.body.buffer.limit property in message-processor.properties. For example: conf_http_HTTPResponse.body.buffer.limit=5m 3. Restart the Message Processor: \> /\/apigee/apigee-service/bin/apigee-service edge-message-processor restart 4. Repeat for all Message Processors. > [!NOTE] > With streaming enabled, Apigee strongly recommends you do **not** attach policies that require access to the request or response payload. Those types of policies will either cause errors or trigger buffering in the API proxy, which limits payload size to the numbers listed above and defeats the purpose of enabling streaming to handle large payloads. You can attach policies that do not interact with the request/response body, such as authentication or message logging policies. ## How to enable request and response streaming To enable request streaming you need to add the `request.streaming.enabled` property to the ProxyEndpoint and TargetEndpoint definitions in the proxy bundle and set it to `true`. Similarly, set the `response.streaming.enabled` property to enable response streaming. You can locate these configuration files in the management UI in the Develop view for your proxy. If you are developing locally, these definition files are in `apiproxy/proxies` and `apiproxy/targets`. This sample shows how to enable both request and response streaming in the TargetEndpoint definition. ``` http://mocktarget.apigee.net true true true User-Agent,Referer,Accept-Language apikey ``` This example shows how to enable response and request streaming in the ProxyEndpoint definition: ``` /v1/weather true true true ``` For more information about configuring endpoint definitions, see [Endpoint properties reference](https://docs.apigee.com/api-platform/reference/endpoint-properties-reference). ## Related code samples API proxy samples on GitHub are easy to download and use. See [Using the sample API proxies](https://docs.apigee.com/api-platform/samples/using-samples) for information about downloading and using the samples. Sample proxies that feature streaming include: - [streaming](https://github.com/apigee/api-platform-samples/tree/master/sample-proxies/streaming) - Demonstrates an API proxy configured for HTTP streaming. - [Edge Callout: Signed URL Generator](https://github.com/DinoChiesa/ApigeeEdge-Java-GoogleUrlSigner) - Illustrates the best practice of generating a signed URL to access large files instead of trying to stream them in a request/response.