Refactor project structure for a better development (#3552)

#### What type of PR is this?

/kind cleanup
/area core

#### What this PR does / why we need it:

This PR totally refactor project structure for a better plugin development. Now we can maintain and publish api and platform modules at Halo application side, which will be references by plugins.

Currently, we can execute command `./gradlew clean publish` to publish api and platform modules into **local** Maven repository, so that we can refer these dependencies (`run.halo.tools.platform:plugin:2.4.0-SNAPSHOT` and `run.halo.app:api:2.4.0-SNAPSHOT`) in plugin projects. 

I will make another pull request to publish api library and platforms into Maven central repository.

**Modules explanation**:
- API module contains common classes which might be used by plugins.
- Plugin Platform module contains dependency declarations of other plugin API modules.
- Application Platform module contains dependency declarations application module might uses.

If we want to build application only(exclude check and jar), we have to execute the command below:

```bash
./gradlew clean :application:build -x :application:check -x :application:jar
```

The executable Jar will be generated at folder `application/build/libs/`.

If we want to build a Docker image, we could execute the command below:

```bash
docker build -t johnniang/halo:project-structure .

# Test the Docker image
docker run -it --rm -p8090:8090 johnniang/halo:project-structure
```

#### Which issue(s) this PR fixes:

Fixes #2730

#### Special notes for your reviewer:

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

```release-note
重构项目结构
```

.dockerignore

@@ -0,0 +1,3 @@
+console
+.github
+.git

.gitignore

@@ -5,8 +5,8 @@ logs/
 
 ### Gradle
 .gradle
-/build/
-/out/
+build/
+out/
 !gradle/wrapper/gradle-wrapper.jar
 bin/
 
@@ -71,7 +71,7 @@ application-local.yaml
 application-local.properties
 
 ### Zip file for test
-!src/test/resources/themes/*.zip
-!src/main/resources/themes/*.zip
-src/main/resources/console/
-src/main/resources/presets/
+!application/src/test/resources/themes/*.zip
+!application/src/main/resources/themes/*.zip
+application/src/main/resources/console/
+application/src/main/resources/presets/

Dockerfile

@@ -1,6 +1,6 @@
 FROM eclipse-temurin:17-jre as builder
 WORKDIR application
-ARG JAR_FILE=build/libs/halo-*.jar
+ARG JAR_FILE=application/build/libs/*.jar
 COPY ${JAR_FILE} application.jar
 RUN java -Djarmode=layertools -jar application.jar extract
 

api/build.gradle

@@ -0,0 +1,81 @@
+plugins {
+    id 'java-library'
+    id 'maven-publish'
+    id "io.freefair.lombok" version "8.0.0-rc2"
+}
+
+group = 'run.halo.app'
+description = 'API of halo project, connecting by other projects.'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    api platform(project(':platform:application'))
+
+    api 'org.springframework.boot:spring-boot-starter-actuator'
+    api 'org.springframework.boot:spring-boot-starter-data-jpa'
+    api 'org.springframework.boot:spring-boot-starter-mail'
+    api 'org.springframework.boot:spring-boot-starter-thymeleaf'
+    api 'org.springframework.boot:spring-boot-starter-webflux'
+    api 'org.springframework.boot:spring-boot-starter-validation'
+    api 'org.springframework.boot:spring-boot-starter-data-r2dbc'
+
+    // Spring Security
+    api 'org.springframework.boot:spring-boot-starter-security'
+    api 'org.springframework.security:spring-security-oauth2-jose'
+    api 'org.springframework.security:spring-security-oauth2-client'
+    api 'org.springframework.security:spring-security-oauth2-resource-server'
+
+    api "org.springdoc:springdoc-openapi-starter-webflux-ui"
+    api 'org.openapi4j:openapi-schema-validator'
+    api "net.bytebuddy:byte-buddy"
+
+    // Apache Lucene
+    api "org.apache.lucene:lucene-core"
+    api "org.apache.lucene:lucene-queryparser"
+    api "org.apache.lucene:lucene-highlighter"
+    api "org.apache.lucene:lucene-backward-codecs"
+    api 'cn.shenyanchao.ik-analyzer:ik-analyzer'
+
+    api "org.apache.commons:commons-lang3"
+    api "io.seruco.encoding:base62"
+    api "org.pf4j:pf4j"
+    api "com.google.guava:guava"
+    api "org.jsoup:jsoup"
+    api "io.github.java-diff-utils:java-diff-utils"
+    api "org.springframework.integration:spring-integration-core"
+    api "com.github.java-json-tools:json-patch"
+    api "org.thymeleaf.extras:thymeleaf-extras-springsecurity6"
+
+    runtimeOnly 'io.r2dbc:r2dbc-h2'
+    runtimeOnly 'org.postgresql:postgresql'
+    runtimeOnly 'org.postgresql:r2dbc-postgresql'
+    runtimeOnly 'org.mariadb:r2dbc-mariadb'
+    runtimeOnly 'com.github.jasync-sql:jasync-r2dbc-mysql'
+
+    testImplementation 'org.springframework.boot:spring-boot-starter-test'
+    testImplementation 'org.springframework.security:spring-security-test'
+    testImplementation 'io.projectreactor:reactor-test'
+}
+
+java {
+    withSourcesJar()
+    withJavadocJar()
+}
+
+tasks.named('test') {
+    useJUnitPlatform()
+}
+
+publishing {
+    publications {
+        library(MavenPublication) {
+            from components.java
+        }
+    }
+    repositories {
+        mavenLocal()
+    }
+}

src/main/java/run/halo/app/content/comment/CommentSubject.java → api/src/main/java/run/halo/app/content/comment/CommentSubject.java

@@ -2,7 +2,7 @@
 
 import org.pf4j.ExtensionPoint;
 import reactor.core.publisher.Mono;
-import run.halo.app.extension.AbstractExtension;
+import run.halo.app.extension.Extension;
 import run.halo.app.extension.Ref;
 
 /**
@@ -11,7 +11,7 @@
  * @author guqing
  * @since 2.0.0
  */
-public interface CommentSubject<T extends AbstractExtension>  extends ExtensionPoint {
+public interface CommentSubject<T extends Extension>  extends ExtensionPoint {
 
     Mono<T> get(String name);
 

api/src/main/java/run/halo/app/core/extension/Counter.java

@@ -0,0 +1,41 @@
+package run.halo.app.core.extension;
+
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+import run.halo.app.extension.AbstractExtension;
+import run.halo.app.extension.GVK;
+import run.halo.app.extension.Metadata;
+
+/**
+ * A counter for number of requests by extension resource name.
+ *
+ * @author guqing
+ * @since 2.0.0
+ */
+@Data
+@GVK(group = "metrics.halo.run", version = "v1alpha1", kind = "Counter", plural = "counters",
+    singular = "counter")
+@EqualsAndHashCode(callSuper = true)
+public class Counter extends AbstractExtension {
+
+    private Integer visit;
+
+    private Integer upvote;
+
+    private Integer downvote;
+
+    private Integer totalComment;
+
+    private Integer approvedComment;
+
+    public static Counter emptyCounter(String name) {
+        Counter counter = new Counter();
+        counter.setMetadata(new Metadata());
+        counter.getMetadata().setName(name);
+        counter.setUpvote(0);
+        counter.setTotalComment(0);
+        counter.setApprovedComment(0);
+        counter.setVisit(0);
+        return counter;
+    }
+}

src/main/java/run/halo/app/core/extension/content/Post.java → api/src/main/java/run/halo/app/core/extension/content/Post.java

@@ -13,10 +13,10 @@
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
 import run.halo.app.extension.AbstractExtension;
-import run.halo.app.extension.ExtensionUtil;
 import run.halo.app.extension.GVK;
 import run.halo.app.extension.GroupVersionKind;
 import run.halo.app.extension.MetadataOperator;
+import run.halo.app.extension.MetadataUtil;
 import run.halo.app.infra.ConditionList;
 
 /**
@@ -255,11 +255,6 @@ public Builder published(Boolean published) {
                 return this;
             }
 
-            /**
-             * Build compact post.
-             *
-             * @return a compact post
-             */
             public CompactPost build() {
                 CompactPost compactPost = new CompactPost();
                 compactPost.setName(name);
@@ -271,7 +266,7 @@ public CompactPost build() {
     }
 
     public static void changePublishedState(Post post, boolean value) {
-        Map<String, String> labels = ExtensionUtil.nullSafeLabels(post);
+        Map<String, String> labels = MetadataUtil.nullSafeLabels(post);
         labels.put(PUBLISHED_LABEL, String.valueOf(value));
     }
 }

src/main/java/run/halo/app/core/extension/content/SinglePage.java → api/src/main/java/run/halo/app/core/extension/content/SinglePage.java

@@ -9,9 +9,9 @@
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
 import run.halo.app.extension.AbstractExtension;
-import run.halo.app.extension.ExtensionUtil;
 import run.halo.app.extension.GVK;
 import run.halo.app.extension.GroupVersionKind;
+import run.halo.app.extension.MetadataUtil;
 
 /**
  * <p>Single page extension.</p>
@@ -112,7 +112,7 @@ public static class SinglePageStatus extends Post.PostStatus {
     }
 
     public static void changePublishedState(SinglePage page, boolean value) {
-        Map<String, String> labels = ExtensionUtil.nullSafeLabels(page);
+        Map<String, String> labels = MetadataUtil.nullSafeLabels(page);
         labels.put(PUBLISHED_LABEL, String.valueOf(value));
     }
 }

src/main/java/run/halo/app/core/extension/content/Snapshot.java → api/src/main/java/run/halo/app/core/extension/content/Snapshot.java

@@ -1,17 +1,13 @@
 package run.halo.app.core.extension.content;
 
-import com.fasterxml.jackson.annotation.JsonIgnore;
 import io.swagger.v3.oas.annotations.media.Schema;
 import java.time.Instant;
 import java.util.LinkedHashSet;
 import java.util.Set;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
-import org.apache.commons.lang3.StringUtils;
 import org.springframework.util.Assert;
-import run.halo.app.content.ContentWrapper;
-import run.halo.app.content.PatchUtils;
 import run.halo.app.extension.AbstractExtension;
 import run.halo.app.extension.GVK;
 import run.halo.app.extension.Ref;
@@ -69,27 +65,4 @@ public static void addContributor(Snapshot snapshot, String name) {
         contributors.add(name);
     }
 
-    @JsonIgnore
-    public ContentWrapper applyPatch(Snapshot baseSnapshot) {
-        Assert.notNull(baseSnapshot, "The baseSnapshot must not be null.");
-        String baseSnapshotName = baseSnapshot.getMetadata().getName();
-        if (StringUtils.equals(getMetadata().getName(), baseSnapshotName)) {
-            return ContentWrapper.builder()
-                .snapshotName(this.getMetadata().getName())
-                .raw(this.spec.rawPatch)
-                .content(this.spec.contentPatch)
-                .rawType(this.spec.rawType)
-                .build();
-        }
-        String patchedContent =
-            PatchUtils.applyPatch(baseSnapshot.getSpec().getContentPatch(), this.spec.contentPatch);
-        String patchedRaw =
-            PatchUtils.applyPatch(baseSnapshot.getSpec().getRawPatch(), this.spec.rawPatch);
-        return ContentWrapper.builder()
-            .snapshotName(this.getMetadata().getName())
-            .raw(patchedRaw)
-            .content(patchedContent)
-            .rawType(this.spec.rawType)
-            .build();
-    }
 }

src/main/java/run/halo/app/extension/ExtensionClient.java → api/src/main/java/run/halo/app/extension/ExtensionClient.java

@@ -8,20 +8,21 @@
 /**
  * ExtensionClient is an interface which contains some operations on Extension instead of
  * ExtensionStore.
+ * <br/><br/>
+ * Please note that this client can only use in non-reactive environment. If you want to
+ * use Extension client in reactive environment, please use {@link ReactiveExtensionClient} instead.
  *
  * @author johnniang
- * @apiNote Please note that this client can only use in non-reactive environment. If you want to
- * use Extension client in reactive environment, please use {@link ReactiveExtensionClient} instead.
  */
 public interface ExtensionClient {
 
     /**
      * Lists Extensions by Extension type, filter and sorter.
      *
-     * @param type is the class type of Extension.
-     * @param predicate filters the reEnqueue.
+     * @param type       is the class type of Extension.
+     * @param predicate  filters the reEnqueue.
      * @param comparator sorts the reEnqueue.
-     * @param <E> is Extension type.
+     * @param <E>        is Extension type.
      * @return all filtered and sorted Extensions.
      */
     <E extends Extension> List<E> list(Class<E> type, Predicate<E> predicate,
@@ -30,12 +31,12 @@ <E extends Extension> List<E> list(Class<E> type, Predicate<E> predicate,
     /**
      * Lists Extensions by Extension type, filter, sorter and page info.
      *
-     * @param type is the class type of Extension.
-     * @param predicate filters the reEnqueue.
+     * @param type       is the class type of Extension.
+     * @param predicate  filters the reEnqueue.
      * @param comparator sorts the reEnqueue.
-     * @param page is page number which starts from 0.
-     * @param size is page size.
-     * @param <E> is Extension type.
+     * @param page       is page number which starts from 0.
+     * @param size       is page size.
+     * @param <E>        is Extension type.
      * @return a list of Extensions.
      */
     <E extends Extension> ListResult<E> list(Class<E> type, Predicate<E> predicate,
@@ -46,7 +47,7 @@ <E extends Extension> ListResult<E> list(Class<E> type, Predicate<E> predicate,
      *
      * @param type is Extension type.
      * @param name is Extension name.
-     * @param <E> is Extension type.
+     * @param <E>  is Extension type.
      * @return an optional Extension.
      */
     <E extends Extension> Optional<E> fetch(Class<E> type, String name);
@@ -58,26 +59,26 @@ <E extends Extension> ListResult<E> list(Class<E> type, Predicate<E> predicate,
      * Creates an Extension.
      *
      * @param extension is fresh Extension to be created. Please make sure the Extension name does
-     * not exist.
-     * @param <E> is Extension type.
+     *                  not exist.
+     * @param <E>       is Extension type.
      */
     <E extends Extension> void create(E extension);
 
     /**
      * Updates an Extension.
      *
      * @param extension is an Extension to be updated. Please make sure the resource version is
-     * latest.
-     * @param <E> is Extension type.
+     *                  latest.
+     * @param <E>       is Extension type.
      */
     <E extends Extension> void update(E extension);
 
     /**
      * Deletes an Extension.
      *
      * @param extension is an Extension to be deleted. Please make sure the resource version is
-     * latest.
-     * @param <E> is Extension type.
+     *                  latest.
+     * @param <E>       is Extension type.
      */
     <E extends Extension> void delete(E extension);