Clear cache on reload

CHANGELOG.md

@@ -108,6 +108,7 @@
 - [Added `Table.input` allowing creation of typed tables from vectors of data,
   including auto parsing text columns.][11562]
 - [Enhance Managed_Resource to allow implementation of in-memory caches][11577]
+- [The reload button clears the HTTP cache.][11673]
 
 [11235]: https://github.com/enso-org/enso/pull/11235
 [11255]: https://github.com/enso-org/enso/pull/11255
@@ -116,6 +117,7 @@
 [11490]: https://github.com/enso-org/enso/pull/11490
 [11562]: https://github.com/enso-org/enso/pull/11562
 [11577]: https://github.com/enso-org/enso/pull/11577
+[11673]: https://github.com/enso-org/enso/pull/11673
 
 #### Enso Language & Runtime
 

distribution/lib/Standard/Base/0.0.0-dev/src/Network/Reload_Detector.enso

@@ -0,0 +1,31 @@
+import Standard.Base.Error.Error
+import Standard.Base.Meta
+import Standard.Base.Nothing.Nothing
+import Standard.Base.Runtime.Managed_Resource.Managed_Resource
+import Standard.Base.Runtime.Ref.Ref
+from Standard.Base.Data.Boolean import Boolean, True, False
+
+## PRIVATE
+   This is used by ReloadDetector.java to create a `Managed_Resource` that is
+   garbage collected when the reload button is pressed.
+
+   The managed resource contains a Ref containing a 0 (the value is
+   unimportant). When the reload button is pressed, the ref is removed and
+   attempting to access it using `with` throws an `Uninitialized_State`. When
+   the `Uninitialized_State` is detected, it indicates that the reload has been
+   initiated.
+type Reload_Detector
+    private Value mr:Managed_Resource
+
+    new -> Reload_Detector =
+        mr = Managed_Resource.register (Ref.new 1) (x-> Nothing) True
+        Reload_Detector.Value mr
+
+    has_reload_occurred self =
+        self.mr.has_been_finalized
+
+## PRIVATE
+simulate_reload_test_only reload_detector = reload_detector.mr.finalize
+
+## PRIVATE
+create_reload_detector = Reload_Detector.new

distribution/lib/Standard/Base/0.0.0-dev/src/Runtime/Managed_Resource.enso

@@ -1,8 +1,10 @@
 ## An API for manual resource management.
 
 import project.Any.Any
+import project.Errors.Common.Uninitialized_State
+import project.Meta
 import project.Nothing.Nothing
-from project.Data.Boolean import Boolean, False
+from project.Data.Boolean import Boolean, True, False
 
 ## Resource provides an API for manual management of computation resources.
 
@@ -90,5 +92,15 @@ type Managed_Resource
     take : Any
     take self = @Builtin_Method "Managed_Resource.take"
 
+    ## PRIVATE
+       ADVANCED
+
+       Returns true iff the resource has been collected by the engine, false
+       otherwise. If `with` throws any other error, it is propagated.
+    has_been_finalized : Boolean
+    has_been_finalized self -> Boolean = self.with x->
+        if x.is_error.not then False else
+            if x.catch.is_a Uninitialized_State then True else x
+
 register_builtin r fn sys:Boolean = @Builtin_Method "Managed_Resource.register_builtin"
 with_builtin r fn = @Builtin_Method "Managed_Resource.with_builtin"

engine/runtime-instrument-common/src/main/scala/org/enso/interpreter/instrument/command/RecomputeContextCmd.scala

@@ -11,6 +11,7 @@ import org.enso.interpreter.instrument.{
 }
 import org.enso.interpreter.instrument.execution.RuntimeContext
 import org.enso.interpreter.instrument.job.{EnsureCompiledJob, ExecuteJob}
+import org.enso.interpreter.runtime.EnsoContext
 import org.enso.polyglot.runtime.Runtime.Api
 import org.enso.polyglot.runtime.Runtime.Api.RequestId
 
@@ -42,6 +43,10 @@ class RecomputeContextCmd(
     ec: ExecutionContext
   ): Future[Boolean] = {
     Future {
+      EnsoContext
+        .get(null)
+        .getResourceManager()
+        .scheduleFinalizationOfSystemReferences();
       ctx.jobControlPlane.abortJobs(
         request.contextId,
         "recompute context",

std-bits/base/src/main/java/org/enso/base/cache/LRUCache.java

@@ -73,6 +73,9 @@ public class LRUCache<M> {
   /** Used to get the current free disk space; mockable. */
   private final DiskSpaceGetter diskSpaceGetter;
 
+  /** Used to clear the cache on reload. */
+  private final ReloadDetector reloadDetector = new ReloadDetector();
+
   public LRUCache() {
     this(LRUCacheSettings.getDefault(), new NowGetter(), new DiskSpaceGetter());
   }
@@ -89,6 +92,8 @@ public LRUCache(LRUCacheSettings settings, NowGetter nowGetter, DiskSpaceGetter
    */
   public CacheResult<M> getResult(ItemBuilder<M> itemBuilder)
       throws IOException, InterruptedException, ResponseTooLargeException {
+    clearOnReload();
+
     String cacheKey = itemBuilder.makeCacheKey();
 
     try {
@@ -221,6 +226,12 @@ public void clear() {
     removeCacheEntriesByPredicate(e -> true);
   }
 
+  private void clearOnReload() {
+    if (reloadDetector.hasReloadOccurred()) {
+      clear();
+    }
+  }
+
   /** Remove all cache entries (and their cache files) that match the predicate. */
   private void removeCacheEntriesByPredicate(Predicate<CacheEntry<M>> predicate) {
     List<Map.Entry<String, CacheEntry<M>>> toRemove =
@@ -344,6 +355,11 @@ public LRUCacheSettings getSettings() {
     return settings;
   }
 
+  /** Public for testing. */
+  public void simulateReloadTestOnly() {
+    reloadDetector.simulateReloadTestOnly();
+  }
+
   private record CacheEntry<M>(File responseData, M metadata, long size, ZonedDateTime expiry) {}
 
   /**

std-bits/base/src/main/java/org/enso/base/cache/ReloadDetector.java

@@ -0,0 +1,39 @@
+package org.enso.base.cache;
+
+import org.enso.base.polyglot.EnsoMeta;
+import org.graalvm.polyglot.Value;
+
+/**
+ * Detects that the reload button has been pressed.
+ *
+ * <p>.hasReloadOccurred() returns true if the reload button was pressed since the last call to
+ * .hasReloadOccurred().
+ *
+ * <p>This uses a `Managed_Resource` (created in eval'd Enso code) that is cleared on reload.
+ */
+public class ReloadDetector {
+  private Value ensoReloadDetector;
+
+  public ReloadDetector() {
+    resetEnsoReloadDetector();
+  }
+
+  public boolean hasReloadOccurred() {
+    var reloadHasOccurred = ensoReloadDetector.invokeMember("has_reload_occurred").asBoolean();
+    if (reloadHasOccurred) {
+      resetEnsoReloadDetector();
+    }
+    return reloadHasOccurred;
+  }
+
+  private void resetEnsoReloadDetector() {
+    ensoReloadDetector =
+        EnsoMeta.callStaticModuleMethod(
+            "Standard.Base.Network.Reload_Detector", "create_reload_detector");
+  }
+
+  void simulateReloadTestOnly() {
+    EnsoMeta.callStaticModuleMethod(
+        "Standard.Base.Network.Reload_Detector", "simulate_reload_test_only", ensoReloadDetector);
+  }
+}

std-bits/base/src/main/java/org/enso/base/enso_cloud/EnsoSecretHelper.java

@@ -19,12 +19,10 @@
 import org.enso.base.net.URISchematic;
 import org.enso.base.net.URIWithSecrets;
 import org.graalvm.collections.Pair;
-import org.graalvm.polyglot.Context;
-import org.graalvm.polyglot.Value;
 
 /** Makes HTTP requests with secrets in either header or query string. */
 public final class EnsoSecretHelper extends SecretValueResolver {
-  private static Value cache;
+  private static EnsoHTTPResponseCache cache;
 
   /** Gets a JDBC connection resolving EnsoKeyValuePair into the properties. */
   public static Connection getJDBCConnection(
@@ -179,43 +177,10 @@ public EnsoHttpResponse reconstructResponseFromCachedStream(
   }
 
   public static EnsoHTTPResponseCache getOrCreateCache() {
-    if (getCache() instanceof EnsoHTTPResponseCache httpCache) {
-      return httpCache;
-    } else {
-      var module =
-          Context.getCurrent()
-              .eval(
-                  "enso",
-                  """
-      import Standard.Base.Runtime.Managed_Resource.Managed_Resource
-      import Standard.Base.Data.Boolean.Boolean
-
-      type Cache
-          private Value ref:Managed_Resource
-
-          new obj -> Cache =
-              on_finalize _ = 0
-              ref = Managed_Resource.register obj on_finalize Boolean.True
-              Cache.Value ref
-
-          get self = self.ref.with (r->r)
-      """);
-      var cacheNew = module.invokeMember("eval_expression", "Cache.new");
-      var httpCache = new EnsoHTTPResponseCache();
-      cache = cacheNew.execute(httpCache);
-      return httpCache;
-    }
-  }
-
-  public static EnsoHTTPResponseCache getCache() {
-    var c = cache instanceof Value v ? v.invokeMember("get") : null;
-    if (c != null
-        && c.isHostObject()
-        && c.asHostObject() instanceof EnsoHTTPResponseCache httpCache) {
-      return httpCache;
-    } else {
-      return null;
+    if (cache == null) {
+      cache = new EnsoHTTPResponseCache();
     }
+    return cache;
   }
 
   private static final Comparator<Pair<String, String>> headerNameComparator =

test/Base_Tests/src/Runtime/Managed_Resource_Spec.enso

@@ -95,6 +95,7 @@ add_specs suite_builder = suite_builder.group "Managed_Resource" group_builder->
 
             # finalizes the resource
             mr.finalize
+            mr.has_been_finalized . should_be_true
             builder.append "Finalized:"+mr.to_text
 
             # operation on finalized resource

test/Table_Tests/src/IO/Fetch_Spec.enso

@@ -172,6 +172,9 @@ add_specs suite_builder =
             lru_cache = LRUCache.new
             with_lru_cache lru_cache action
 
+        fake_reload =
+            EnsoSecretHelper.getOrCreateCache.getLRUCache.simulateReloadTestOnly
+
         url0 = base_url_with_slash+'test_download?max-age=16&length=10'
         url1 = base_url_with_slash+'test_download?max-age=16&length=20'
         url_post = base_url_with_slash + "post"
@@ -517,6 +520,27 @@ add_specs suite_builder =
             Test_Environment.unsafe_with_environment_override "ENSO_LIB_HTTP_CACHE_MAX_TOTAL_CACHE_LIMIT" "101%" <|
                 LRUCache.new . getSettings . getTotalCacheLimit . should_equal (TotalCacheLimit.Percentage.new 0.2)
 
+        group_builder.specify "Cache should be cleared when a reload is detected" <|
+            HTTP.fetch base_url_with_slash+'test_download?length=10'
+            HTTP.fetch base_url_with_slash+'test_download?length=11'
+            HTTP.fetch base_url_with_slash+'test_download?length=12'
+            get_num_response_cache_entries . should_equal 3
+
+            fake_reload
+
+            get_num_response_cache_entries . should_equal 3  # Cleaning is not triggered until the next request
+            HTTP.fetch base_url_with_slash+'test_download?length=10'
+            get_num_response_cache_entries . should_equal 1
+            HTTP.fetch base_url_with_slash+'test_download?length=14'
+            HTTP.fetch base_url_with_slash+'test_download?length=15'
+            get_num_response_cache_entries . should_equal 3
+
+            fake_reload
+
+            get_num_response_cache_entries . should_equal 3  # Cleaning is not triggered until the next request
+            HTTP.fetch base_url_with_slash+'test_download?length=16'
+            get_num_response_cache_entries . should_equal 1
+
         group_builder.specify "Reissues the request if the cache file disappears" pending=pending_has_url <| Test.with_retries <|
             with_default_cache <|
                 url = base_url_with_slash+'test_download?max-age=16&length=10'