Merge pull request #3545 from cloudflare/mar/memory-cache-delete

Implement delete operation for memory cache.
cloudflare · Feb 21, 2025 · f7bcdbb · f7bcdbb
2 parents ce57483 + b40aae2
commit f7bcdbb
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Showing 4 changed files with 31 additions and 1 deletion.
diff --git a/src/workerd/api/BUILD.bazel b/src/workerd/api/BUILD.bazel
@@ -76,6 +76,7 @@ wd_cc_library(
     ],
     visibility = ["//visibility:public"],
     deps = [
+        "//src/workerd/io:compatibility-date_capnp",
         "//src/workerd/jsg",
         "//src/workerd/util:uuid",
     ],

diff --git a/src/workerd/api/memory-cache.c++ b/src/workerd/api/memory-cache.c++
@@ -349,6 +349,11 @@ void SharedMemoryCache::Use::handleFallbackFailure(InProgress& inProgress) const
   }
 }
 
+void SharedMemoryCache::Use::delete_(const kj::String& key) const {
+  auto data = cache->data.lockExclusive();
+  cache->removeIfExistsWhileLocked(*data, key);
+}
+
 // Attempts to serialize a JavaScript value. If that fails, this function throws
 // a tunneled exception, see jsg::createTunneledException().
 static kj::Own<CacheValue> hackySerialize(jsg::Lock& js, jsg::JsRef<jsg::JsValue>& value) {
@@ -444,6 +449,16 @@ jsg::Promise<jsg::JsRef<jsg::JsValue>> MemoryCache::read(jsg::Lock& js,
   }
 }
 
+void MemoryCache::delete_(jsg::Lock& js, jsg::NonCoercible<kj::String> key) {
+  // Ignore operations on keys exceeding key max size.
+  if (key.value.size() > MAX_KEY_SIZE) {
+    js.throwException(js.rangeError("Key too large."_kj));
+    return;
+  }
+
+  cacheUse.delete_(key.value);
+}
+
 // ======================================================================================
 
 MemoryCacheProvider::MemoryCacheProvider(const kj::MonotonicClock& timer,

diff --git a/src/workerd/api/memory-cache.h b/src/workerd/api/memory-cache.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <workerd/io/compatibility-date.capnp.h>
 #include <workerd/jsg/jsg.h>
 #include <workerd/util/uuid.h>
 
@@ -201,6 +202,8 @@ class SharedMemoryCache: public kj::AtomicRefcounted {
     kj::OneOf<kj::Own<CacheValue>, kj::Promise<GetWithFallbackOutcome>> getWithFallback(
         const kj::String& key, SpanBuilder& span) const;
 
+    void delete_(const kj::String& key) const;
+
    private:
     // Creates a new FallbackDoneCallback associated with the given
     // InProgress struct. This is called whenever getWithFallback() wants to
@@ -482,8 +485,14 @@ class MemoryCache: public jsg::Object {
       jsg::NonCoercible<kj::String> key,
       jsg::Optional<FallbackFunction> optionalFallback);
 
-  JSG_RESOURCE_TYPE(MemoryCache) {
+  // Delete a value from the cache.
+  void delete_(jsg::Lock& js, jsg::NonCoercible<kj::String> key);
+
+  JSG_RESOURCE_TYPE(MemoryCache, CompatibilityFlags::Reader flags) {
     JSG_METHOD(read);
+    if (flags.getMemoryCacheDelete()) {
+      JSG_METHOD_NAMED(delete, delete_);
+    }
   }
 
  private:

diff --git a/src/workerd/io/compatibility-date.capnp b/src/workerd/io/compatibility-date.capnp
@@ -692,4 +692,9 @@ struct CompatibilityFlags @0x8f8c1b68151b6cef {
       $experimental
       $neededByFl;
   # Enables cache settings specified request in fetch api cf object to override cache rules. (only for user owned or grey-clouded sites)
+
+  memoryCacheDelete @73 :Bool
+      $compatEnableFlag("memory_cache_delete")
+      $experimental;
+  # Enables delete operations on memory cache if enabled.
 }