Cache api integration (v2) (#856)

* Add support to deno deploy cache api implementation

Documentation for deno's Edge Cache are available at https://docs.deno.com/deploy/manual/edge-cache/

This commit contains the following alterations:
* Add CACHE_API as default cache engine, which replaces KV in our DD websites (This does not afect the k8s websites, as they are by default using the FILE_SYSTEM cache).
* Change LOADER_CACHE_START_THRESHOLD env var to 0
* Change LOADER_CACHE_SIZE to 1_024_000
* Add Content-Type field to cached response header
* Add Content-Length field to cached response header if length is available

* Great cache revamp

* Refact cache

* Enable loader cache by default

* Lint, code readability and better env names

* Fixed env names

* Improve env names and default

* Fix format

---------

Co-authored-by: Itamar Rocha Filho <[email protected]>

Author: matheusgr

README.md

@@ -171,17 +171,13 @@ Here is a table with the integrations that we have built and the statuses of the
 ## Cache env vars (WIP)
 | Environment Variable              | Description                                             | Example Value                                          |
 |-----------------------------------|---------------------------------------------------------|--------------------------------------------------------|
-| `CACHE_UPLOAD_BUCKET`             | The AWS S3 bucket name for cache uploads                | `BUCKET-NAME`                                       |
-| `CACHE_AWS_REGION`                | AWS region where the cache bucket is located            | `sa-east-1`                                            |
-| `CACHE_AWS_ACCESS_KEY_ID`         | AWS access key ID for authentication                    | ``                                 |
-| `CACHE_AWS_SECRET_ACCESS_KEY`     | AWS secret access key for authentication                | ``             |
 | `ENABLE_LOADER_CACHE`             | Flag to enable or disable the loader cache              | `true`                                                 |
 | `LOADER_CACHE_START_TRESHOLD`     | Cache start threshold                                   | `0`                                                    |
-| `WEB_CACHE_ENGINE`                | Defines the cache engine(s) to use                      | `"FILE_SYSTEM,S3"`                                     |
-| `FILE_SYSTEM_CACHE_DIRECTORY`     | Directory path for file system cache                    | `` |
-| `MAX_CACHE_SIZE`                  | Maximum size of the file system cache (in bytes)                    | `1073741824` (1 GB)                                    |
-| `TTL_AUTOPURGE`                   | Flag to automatically delete expired items from the file system cache (cpu intensive) | `false`                                      |
-| `TTL_RESOLUTION`                  | Time interval to check for expired items in the file system cache (in milliseconds) | `30000` (30 seconds)                               |
+| `WEB_CACHE_ENGINE`                | Defines the cache engine(s) to use                      | `"FILE_SYSTEM,CACHE_API"`                                     |
+| `FILE_SYSTEM_CACHE_DIRECTORY`     | Directory path for file system cache                    | `/tmp` |
+| `CACHE_MAX_SIZE`                  | Maximum size of the file system cache (in bytes)                    | `1073741824` (1 GB)                                    |
+| `CACHE_TTL_AUTOPURGE`                   | Flag to automatically delete expired items from the file system cache (cpu intensive) | `false`                                      |
+| `CACHE_TTL_RESOLUTION`                  | Time interval to check for expired items in the file system cache (in milliseconds) | `30000` (30 seconds)                               |
 | `CACHE_MAX_AGE_S`                  | Time for cache to become stale | `60` (60 seconds)                              |
 
 

blocks/loader.ts

@@ -118,9 +118,9 @@ export const wrapCaughtErrors = async <
 };
 
 export const LOADER_CACHE_START_TRESHOLD =
-  Deno.env.get("LOADER_CACHE_START_TRESHOLD") ?? 5;
+  Deno.env.get("LOADER_CACHE_START_TRESHOLD") ?? 0;
 
-export const LOADER_CACHE_SIZE = Deno.env.get("LOADER_CACHE_SIZE") ?? 1_024;
+export const LOADER_CACHE_SIZE = Deno.env.get("LOADER_CACHE_SIZE") ?? 1_024_000;
 
 const stats = {
   cache: meter.createCounter("loader_cache", {
@@ -291,13 +291,24 @@ const wrapLoader = (
 
         const callHandlerAndCache = async () => {
           const json = await handler(props, req, ctx);
+          const jsonStringEncoded = new TextEncoder().encode(
+            JSON.stringify(json),
+          );
+
+          const headers: { [key: string]: string } = {
+            expires: new Date(Date.now() + (MAX_AGE_S * 1e3))
+              .toUTCString(),
+            "Content-Type": "application/json",
+          };
+
+          if (jsonStringEncoded && jsonStringEncoded.length > 0) {
+            headers["Content-Length"] = "" + jsonStringEncoded.length;
+          }
+
           cache.put(
             request,
-            new Response(JSON.stringify(json), {
-              headers: {
-                "expires": new Date(Date.now() + (MAX_AGE_S * 1e3))
-                  .toUTCString(),
-              },
+            new Response(jsonStringEncoded, {
+              headers: headers,
             }),
           ).catch((error) => logger.error(`loader error ${error}`));
 

runtime/caches/common.ts

@@ -1,47 +1,6 @@
 import { ValueType } from "../../deps.ts";
 import { tracer } from "../../observability/otel/config.ts";
 import { meter } from "../../observability/otel/metrics.ts";
-import { sha1 } from "../utils.ts";
-
-export const assertNoOptions = (
-  { ignoreMethod, ignoreSearch, ignoreVary }: CacheQueryOptions = {},
-) => {
-  if (ignoreMethod || ignoreSearch || ignoreVary) {
-    throw new Error("Not Implemented");
-  }
-};
-
-export const requestURL = (request: RequestInfo | URL): string => {
-  return typeof request === "string"
-    ? request
-    : request instanceof URL
-    ? request.href
-    : request.url;
-};
-
-export const withCacheNamespace =
-  (cacheName: string) => (request: RequestInfo | URL): Promise<string> => {
-    return requestURLSHA1(request).then((key) => `${key}${cacheName}`);
-  };
-
-export const requestURLSHA1 = (request: RequestInfo | URL): Promise<string> => {
-  return sha1(requestURL(request));
-};
-
-export const assertCanBeCached = (req: Request, response: Response) => {
-  if (!/^http(s?):\/\//.test(req.url)) {
-    throw new TypeError(
-      "Request url protocol must be 'http:' or 'https:'",
-    );
-  }
-  if (req.method !== "GET") {
-    throw new TypeError("Request method must be GET");
-  }
-
-  if (response.status === 206) {
-    throw new TypeError("Response status must not be 206");
-  }
-};
 
 export interface CacheMetrics {
   engine: string;
@@ -63,6 +22,8 @@ export const withInstrumentation = (
       const cacheImpl = await cache.open(cacheName);
       return {
         ...cacheImpl,
+        delete: cacheImpl.delete.bind(cacheImpl),
+        put: cacheImpl.put.bind(cacheImpl),
         match: async (req, opts) => {
           const span = tracer.startSpan("cache-match", {
             attributes: { engine },