Merge pull request #24 from Lombiq/issue/COLI-1199

COLI-1199: Combinator: Clear cache for a fresh deployment

.github/workflows/validate-pull-request.yml

@@ -0,0 +1,10 @@
+name: Validate Pull Request
+
+on:
+  push:
+  pull_request:
+    types: [opened, synchronize]
+
+jobs:
+  validate-pull-request:
+    uses: Lombiq/GitHub-Actions/.github/workflows/validate-pull-request.yml@dev

Constants/FileNames.cs

@@ -0,0 +1,7 @@
+namespace Piedone.Combinator.Constants
+{
+    public static class FileNames
+    {
+        public const string ClearCache = "_" + nameof(ClearCache) + ".txt";
+    }
+}

Constants/FolderNames.cs

@@ -0,0 +1,9 @@
+namespace Piedone.Combinator.Constants
+{
+    public static class FolderNames
+    {
+        public const string PiedoneModules = "_" + nameof(PiedoneModules);
+        public const string Combinator = nameof(Combinator);
+        public const string Sites = nameof(Sites);
+    }
+}

EventHandlers/CombinatorCacheClearingShellEventHandler.cs

@@ -0,0 +1,51 @@
+using Orchard.Environment;
+using Orchard.Environment.Configuration;
+using Orchard.Environment.Extensions;
+using Orchard.FileSystems.AppData;
+using Piedone.Combinator.Constants;
+using Piedone.Combinator.Services;
+
+namespace Piedone.Combinator.EventHandlers
+{
+    [OrchardFeature("Piedone.Combinator")]
+    public class CombinatorCacheClearingShellEventHandler : IOrchardShellEvents
+    {
+        private readonly ICacheFileService _cacheFileService;
+        private readonly IAppDataFolder _appDataFolder;
+        private readonly ShellSettings _shellSettings;
+
+        /// <summary>
+        /// Gets or sets a value indicating whether emptying Combinator cache is disabled, primarily through HostComponents.config.
+        /// </summary>
+        public bool IsDisabled { get; set; } = true;
+
+        public CombinatorCacheClearingShellEventHandler(
+            ICacheFileService cacheFileService,
+            IAppDataFolder appDataFolder,
+            ShellSettings shellSettings)
+        {
+            _cacheFileService = cacheFileService;
+            _appDataFolder = appDataFolder;
+            _shellSettings = shellSettings;
+        }
+
+        public void Activated()
+        {
+            if (IsDisabled) return;
+
+            var pathToClearCacheFile = _appDataFolder.Combine(
+                FolderNames.Sites, _shellSettings.Name, FolderNames.PiedoneModules, FolderNames.Combinator, FileNames.ClearCache);
+
+            if (!_appDataFolder.FileExists(pathToClearCacheFile)) return;
+
+            _cacheFileService.Empty();
+
+            _appDataFolder.DeleteFile(pathToClearCacheFile);
+        }
+
+        public void Terminating()
+        {
+            // Terminating event does not need to be implemented.
+        }
+    }
+}

Piedone.Combinator.csproj

@@ -161,6 +161,8 @@
     <Content Include="Module.txt" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Constants\FolderNames.cs" />
+    <Compile Include="Constants\FileNames.cs" />
     <Compile Include="Commands\CombinatorCommands.cs" />
     <Compile Include="Controllers\AdminController.cs" />
     <Compile Include="Drivers\CombinatorSettingsPartDriver.cs" />
@@ -170,6 +172,7 @@
     <Compile Include="EventHandlers\ICombinatorEventMonitor.cs" />
     <Compile Include="EventHandlers\ICombinatorResourceEventHandler.cs" />
     <Compile Include="EventHandlers\LessPreprocessor.cs" />
+    <Compile Include="EventHandlers\CombinatorCacheClearingShellEventHandler.cs" />
     <Compile Include="EventHandlers\SassPreprocessor.cs" />
     <Compile Include="Extensions\CombinedFileRecordExtensions.cs" />
     <Compile Include="Extensions\RequireSettingsExtensions.cs" />

Readme.md

@@ -28,17 +28,35 @@ An Orchard CMS module that combines and minifies external stylesheets and javasc
 - With custom IStorageProvider can work in cloud hosting too (if there is no write access to the Media folder anyway)
 - Import/export settings
 - Administration page:
-	- Adjust combination exclusion filter
-	- Enable/disable combination of CDN resources
-	- Set up resource domain
-	- Enable/disable minification and adjust exclusion filter
-	- Enable/disable image embedding and adjust exclusion filter
-	- Enable/disable image sprite generation
-	- Define resource sets
-	- Enable/disable for admin site
-	- Empty cache
-
-The module is also available for [DotNest](http://dotnest.com/) sites.  
+    - Adjust combination exclusion filter
+    - Enable/disable combination of CDN resources
+    - Set up resource domain
+    - Enable/disable minification and adjust exclusion filter
+    - Enable/disable image embedding and adjust exclusion filter
+    - Enable/disable image sprite generation
+    - Define resource sets
+    - Enable/disable for admin site
+    - Empty cache
+- The Combinator cache can be emptied when the Activated shell event fires if:
+    - A marker file with the name *_ClearCache.txt* is present in the *Orchard.Web/App_Data/Sites/<tenant_name>/_PiedoneModules/Combinator* folder. This file will then be deleted to have the cache cleared only on the first shell start, e.g. after a new deployment.
+    - The `CombinatorCacheClearingShellEventHandler` class's `IsDisabled` property is set to `false` (default is `true`) by adding the following section to *Orchard.Web/Config/HostComponents.config*:
+        ```
+        <Component Type="Piedone.Combinator.EventHandlers.CombinatorCacheClearingShellEventHandler">
+          <Properties>
+            <Property Name="IsDisabled" Value="false"/>
+          </Properties>
+        </Component>
+        ```
+        Alternatively, the same can be achieved through a file transformation ([see this for details](https://learn.microsoft.com/en-us/aspnet/web-forms/overview/deployment/visual-studio-web-deployment/web-config-transformations)) to only activate this feature for a given build configuration, e.g., by adding the following to *HostComponents.Release.config* for `Release` mode.
+        ```
+        <Component Type="Piedone.Combinator.EventHandlers.CombinatorCacheClearingShellEventHandler" xdt:Transform="Insert">
+          <Properties>
+            <Property Name="IsDisabled" Value="false" xdt:Transform="Insert" />
+          </Properties>
+        </Component>
+        ```
+
+The module is also available for [DotNest](https://dotnest.com) sites.  
 
 You can download an install the module from the [Orchard Gallery](http://orchardproject.net/gallery/List/Modules/Orchard.Module.Piedone.Combinator).  
 For known issues and future plans please see the [Issue Tracker](https://github.com/Lombiq/Combinator/issues).