fix: expose ".del" function on lmdb cache (#32459)

* expose '.del' method on cache instances, mark exposing internal cache instance to be removed in v4

* make gatsby-plugin-sharp work with legacy cache del way and new way with properly exposed del method

* add .del method to ts typings

* add .del method to dummy cache (for onPreInit lifecycle)

packages/gatsby-plugin-sharp/src/gatsby-node.js

@@ -21,6 +21,19 @@ try {
   coreSupportsOnPluginInit = false
 }
 
+function removeCachedValue(cache, key) {
+  if (cache?.del) {
+    // if cache expose ".del" method directly on public interface
+    return cache.del(key)
+  } else if (cache?.cache?.del) {
+    // legacy - using internal cache instance and calling ".del" on it directly
+    return cache.cache.del(key)
+  }
+  return Promise.reject(
+    new Error(`Cache instance doesn't expose ".del" function`)
+  )
+}
+
 exports.onCreateDevServer = async ({ app, cache, reporter }) => {
   if (!_lazyJobsEnabled()) {
     return
@@ -53,14 +66,14 @@ exports.onCreateDevServer = async ({ app, cache, reporter }) => {
     } = splitOperationsByRequestedFile(cacheResult, pathOnDisk)
 
     await _unstable_createJob(matchingJob, { reporter })
-    await cache.cache.del(decodedURI)
+    await removeCachedValue(cache, decodedURI)
 
     if (jobWithRemainingOperations.args.operations.length > 0) {
       // There are still some operations pending for this job - replace the cached job
-      await cache.cache.set(jobContentDigest, jobWithRemainingOperations)
+      await cache.set(jobContentDigest, jobWithRemainingOperations)
     } else {
       // No operations left to process - purge the cache
-      await cache.cache.del(jobContentDigest)
+      await removeCachedValue(cache, jobContentDigest)
     }
 
     return res.sendFile(pathOnDisk)

packages/gatsby/index.d.ts

@@ -1279,6 +1279,15 @@ export interface GatsbyCache {
    * await cache.set(`unique-key`, value)
    */
   set(key: string, value: any): Promise<any>
+
+  /**
+   * Deletes cached value
+   * @param {string} key Cache key
+   * @returns {Promise<void>} Promise resolving once key is deleted from cache
+   * @example
+   * await cache.del(`unique-key`)
+   */
+  del(key: string): Promise<void>
 }
 
 export interface Tracing {

packages/gatsby/src/utils/api-node-helpers-docs.js

@@ -99,6 +99,15 @@ const GatsbyCache = {
    * await cache.set(`unique-key`, value)
    */
   set: true,
+
+  /**
+   * Deletes cached value
+   * @param {string} key Cache key
+   * @returns {Promise<void>} Promise resolving once key is deleted from cache
+   * @example
+   * await cache.del(`unique-key`)
+   */
+  del: true,
 };
 
 /***/

packages/gatsby/src/utils/api-runner-node.js

@@ -240,6 +240,9 @@ const getUninitializedCache = plugin => {
     async set() {
       throw new Error(message)
     },
+    async del() {
+      throw new Error(message)
+    },
   }
 }
 

packages/gatsby/src/utils/cache-lmdb.ts

@@ -19,10 +19,15 @@ export default class GatsbyCacheLmdb {
   public readonly name: string
   // Needed for plugins that want to write data to the cache directory
   public readonly directory: string
+  // TODO: remove `.cache` in v4. This is compat mode - cache-manager cache implementation
+  // expose internal cache that gives access to `.del` function that wasn't available in public
+  // cache interface (gatsby-plugin-sharp use it to clear no longer needed data)
+  public readonly cache: GatsbyCacheLmdb
 
   constructor({ name = `db` }: { name: string }) {
     this.name = name
     this.directory = path.join(process.cwd(), `.cache/caches/${name}`)
+    this.cache = this
   }
 
   init(): GatsbyCacheLmdb {
@@ -59,4 +64,8 @@ export default class GatsbyCacheLmdb {
     await this.getDb().put(key, value)
     return value
   }
+
+  async del(key: string): Promise<void> {
+    return (this.getDb().remove(key) as unknown) as Promise<void>
+  }
 }

packages/gatsby/src/utils/cache.ts

@@ -20,6 +20,9 @@ export default class GatsbyCache {
   public name: string
   public store: Store
   public directory: string
+  // TODO: remove `.cache` in v4. This is compat mode - cache-manager cache implementation
+  // expose internal cache that gives access to `.del` function that wasn't available in public
+  // cache interface (gatsby-plugin-sharp use it to clear no longer needed data)
   public cache?: MultiCache
 
   // @ts-ignore - set & get types are missing from fsStore?
@@ -84,4 +87,14 @@ export default class GatsbyCache {
       })
     })
   }
+
+  async del(key: string): Promise<void> {
+    if (!this.cache) {
+      throw new Error(
+        `GatsbyCache wasn't initialised yet, please run the init method first`
+      )
+    }
+
+    return this.cache.del(key)
+  }
 }