From 5bc4a63e595672320569aba9706497137e7ce56e Mon Sep 17 00:00:00 2001
From: guqing <38999863+guqing@users.noreply.github.com>
Date: Mon, 20 Mar 2023 18:06:26 +0800
Subject: [PATCH] refactor: plugin development initializer (#3539)
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#### What type of PR is this?
/kind improvement
/area core
/milestone 2.4.x

#### What this PR does / why we need it:
去掉开发模式初始化器中加载插件的逻辑，以解决开发模式下启动插件时会遇到的问题
1. 重启插件/Halo启动时 PluginApplicationContext#hash has been closed already.
2. 卸载插件时 NullPointerException at pluginWrapper.getPlugin().stop() becuase 'pluginWrapper' is null
3. Halo 启动时 `Most likely this exception is thrown because the called constructor (xxx) cannot handle 'null' parameters. Original message was:  ...`
4. 以及启动插件后插件的 bean 没有被创建等
```shell
2023-03-20T13:28:02.811+08:00 ERROR 59170 --- [nReconciler-t-1] r.h.a.e.controller.DefaultController     : Reconciler in run.halo.app.core.extension.reconciler.PluginReconciler-worker-1 aborted with an error, re-enqueuing...

java.lang.ArrayIndexOutOfBoundsException: Index -1 out of bounds for length 10
	at java.base/java.util.ArrayList.fastRemove(ArrayList.java:642) ~[na:na]
	at java.base/java.util.ArrayList.remove(ArrayList.java:629) ~[na:na]
	at org.pf4j.AbstractPluginManager.resolvePlugins(AbstractPluginManager.java:797) ~[pf4j-3.9.0.jar:3.9.0]
	at org.pf4j.AbstractPluginManager.loadPlugin(AbstractPluginManager.java:204) ~[pf4j-3.9.0.jar:3.9.0]
	at run.halo.app.core.extension.reconciler.PluginReconciler.lambda$ensurePluginLoaded$17(PluginReconciler.java:495) ~[main/:na]
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.ensurePluginLoaded(PluginReconciler.java:493) ~[main/:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.getPluginWrapper(PluginReconciler.java:322) ~[main/:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.lambda$readinessDetection$1(PluginReconciler.java:117) ~[main/:na]
	at java.base/java.util.Optional.map(Optional.java:260) ~[na:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.readinessDetection(PluginReconciler.java:107) ~[main/:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.lambda$reconcile$0(PluginReconciler.java:95) ~[main/:na]
	at java.base/java.util.Optional.map(Optional.java:260) ~[na:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.reconcile(PluginReconciler.java:87) ~[main/:na]
	at run.halo.app.core.extension.reconciler.PluginReconciler.reconcile(PluginReconciler.java:70) ~[main/:na]
	at run.halo.app.extension.controller.DefaultController$Worker.run(DefaultController.java:163) ~[main/:na]
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539) ~[na:na]
	at java.base/java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:264) ~[na:na]
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java) ~[na:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) ~[na:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) ~[na:na]
	at java.base/java.lang.Thread.run(Thread.java:833) ~[na:na]
```
这些异常信息都是因为原先的 PluginManager 实现不是线程安全的，在 webflux 下使用并且有 Reconciler 的情况下非常容易复现。
所以除了在 Reconciler 调用以外尽量保证 PluginManager 的调用是单线程的，以避免 PluginManager 出现线程安全问题。

how to test it?
在开发模式下配置插件的 fixedPath 来检查差价启用功能是否正常。

#### Does this PR introduce a user-facing change?

```release-note
None
```
---
 .../plugin/PluginDevelopmentInitializer.java  | 36 +++----------------
 1 file changed, 4 insertions(+), 32 deletions(-)

diff --git a/src/main/java/run/halo/app/plugin/PluginDevelopmentInitializer.java b/src/main/java/run/halo/app/plugin/PluginDevelopmentInitializer.java
index 972e49f7c..dac1eee7d 100644
--- a/src/main/java/run/halo/app/plugin/PluginDevelopmentInitializer.java
+++ b/src/main/java/run/halo/app/plugin/PluginDevelopmentInitializer.java
@@ -3,7 +3,6 @@ package run.halo.app.plugin;
 import java.nio.file.Path;
 import java.time.Duration;
 import lombok.extern.slf4j.Slf4j;
-import org.pf4j.PluginWrapper;
 import org.springframework.boot.context.event.ApplicationReadyEvent;
 import org.springframework.context.ApplicationListener;
 import org.springframework.dao.OptimisticLockingFailureException;
@@ -40,30 +39,12 @@ public class PluginDevelopmentInitializer implements ApplicationListener<Applica
         if (!haloPluginManager.isDevelopment()) {
             return;
         }
-        createFixedPluginIfNecessary(haloPluginManager);
+        createFixedPluginIfNecessary();
     }
 
-    private void createFixedPluginIfNecessary(HaloPluginManager pluginManager) {
+    private void createFixedPluginIfNecessary() {
         for (Path path : pluginProperties.getFixedPluginPath()) {
-
-            // Already loaded do not load again
-            String pluginId = idForPath(path);
-
-            // for issue #2901
-            if (pluginId == null) {
-                try {
-                    pluginId = pluginManager.loadPlugin(path);
-                } catch (Exception e) {
-                    log.warn(e.getMessage(), e);
-                    continue;
-                }
-            }
-
-            PluginWrapper pluginWrapper = pluginManager.getPlugin(pluginId);
-            if (pluginWrapper == null) {
-                continue;
-            }
-            Plugin plugin = new YamlPluginFinder().find(pluginWrapper.getPluginPath());
+            Plugin plugin = new YamlPluginFinder().find(path);
             extensionClient.fetch(Plugin.class, plugin.getMetadata().getName())
                 .flatMap(persistent -> {
                     plugin.getMetadata().setVersion(persistent.getMetadata().getVersion());
@@ -75,13 +56,4 @@ public class PluginDevelopmentInitializer implements ApplicationListener<Applica
                 .block();
         }
     }
-
-    protected String idForPath(Path pluginPath) {
-        for (PluginWrapper plugin : haloPluginManager.getPlugins()) {
-            if (plugin.getPluginPath().equals(pluginPath)) {
-                return plugin.getPluginId();
-            }
-        }
-        return null;
-    }
-}
\ No newline at end of file
+}