Cache
The Cache API is designed based on the standard Web API Cache. During the runtime of edge functions, a global
caches object that provides a group of methods for cache-related operations is injected.Note:
The cached content takes effect only on the current data node and is not automatically copied to other data nodes.
Constructor API
Use
caches.default to fetch the default cache instance.// Fetch the default cache instance.const cache = caches.default;// This method provides the same effect as `caches.default`.await caches.open('default');
Use
caches.open to create a cache instance with the specified namespace.// Create a cache instance with the specified namespace.const cache = await caches.open(namespace);
Parameters
The following table describes the parameters of the
caches.open(namespace) method.Parameter | Type | Required | Description |
namespace | string | Yes | The namespace of the cache. The value "default" specifies the default instance. You can also use caches.default to fetch a default instance. |
Methods
match
cache.match(request: string | Request, options?: MatchOptions): Promise<Response | undefined>
The match() method fetches the Response cache associated with the request and returns a Promise object. If the cache exists, the object contains the Response object. If not, the object contains undefined.
Note:
The cache.match() method does not forward requests to the origin. If the cache expires, the method throws a 504 error.
Parameters
Parameter | Type | Required | Description |
request | string | Request | Yes | The request object. The following method and headers are supported: GET Only the GET method is supported. If this parameter is set to a string, the string is used as a URL to construct a Request object. Range If the request contains a Range header and the cached response contains the Accept-Ranges header, the 206 response is returned. If-Modified-Since If the request contains a If-Modified-Since header and the cached response contains a Last-Modified header with the same value as that of the If-Modified-Since header, the 304 response is returned. If-None-Match If the request contains a If-None-Match header and the cached response contains an ETag header with the same value as that of the If-Modified-Since header, the 304 response is returned. |
options | No | The options. |
MatchOptions
Parameter | Type | Example | Description |
ignoreMethod | boolean | true | Specifies whether to ignore the request method. If you set this parameter to true, the request is considered to be a GET request regardless of its actual method. |
put
cache.put(request: string | Request, response: Response): Promise<undefined>
The put() method tries to add a response to the cache by using the given request as the cache key. A
Promise<undefined> object is returned regardless of whether caching is successful.Note:
The put() method returns a 413 error if the Cache-Control header of the object specified in the response parameter instructs not to cache.
Parameters
Parameter | Type | Required | Description |
request | string | Request | Yes | The cache key. GET The request parameter supports only the GET method. If other methods are specified, an error is thrown. string If the request parameter is set to a string, the string is used as a URL to construct a Request object. |
response | Yes | The cache content. Cache-Control Valid values: s-maxage, max-age, no-store, no-cache, and private. The values no-store, no-cache, and private indicate no caching. If you use these values, the cache.put method returns a 413 error. Pragma ETag If the request parameter of the cache.match method contains a If-None-Match header, you can associate it with ETag. Last-Modified if the request parameter of the cache.match method contains a If-Modified-Since header, you can associate it with Last-Modified. 416 Range Not Satisfiable If the object specified in the response parameter is 416 Range Not Satisfiable, no caching is performed. |
Parameter limits
The
cache.put method throws an error in the following scenarios:The
request parameter specifies a method other than the GET method.The status code of the
response parameter is 206 Partial Content. The
response parameter contains a Vary: * header.delete
cache.delete(request: string | Request, options?: DeleteOptions): Promise<boolean>
The delete() method deletes the response associated with the request from the cache. If no network exception occurs, a Promise containing
true is returned. Otherwise, a Promise containing false is returned.Parameters
DeleteOptions
Parameter | Type | Example | Description |
ignoreMethod | boolean | true | Specifies whether to ignore the request method. If you set this parameter to true, the request is considered to be a GET request regardless of its actual method. |