feat: the ConfigMap named system to store user-defined configurations (#2415)

#### What type of PR is this?
/kind improvement
/area core
/milestone 2.0

#### What this PR does / why we need it:
将原来系统默认的系统配置 system 改名为 system-default, 并使用名为 system 的 ConfigMap 来存储用户自定义的系统配置。系统最终配置为用户自定义系统配置 Merge Patch 系统默认配置的结果。
see also #2304
#### Which issue(s) this PR fixes:

Fixes #2304

#### Special notes for your reviewer:
/cc @halo-dev/sig-halo 
#### Does this PR introduce a user-facing change?

```release-note
None
```

build.gradle

@@ -46,6 +46,7 @@ ext {
     javaDiffUtils = "4.12"
     guava = "31.1-jre"
     jsoup = "1.15.2"
+    jsonPatch = "1.13"
 }
 
 dependencies {
@@ -75,6 +76,7 @@ dependencies {
     implementation "org.jsoup:jsoup:$jsoup"
     implementation "io.github.java-diff-utils:java-diff-utils:$javaDiffUtils"
     implementation "org.springframework.integration:spring-integration-core"
+    implementation "com.github.java-json-tools:json-patch:$jsonPatch"
 
     compileOnly 'org.projectlombok:lombok'
     testCompileOnly 'org.projectlombok:lombok'

src/main/java/run/halo/app/config/ExtensionConfiguration.java

@@ -51,6 +51,7 @@ import run.halo.app.extension.controller.ControllerBuilder;
 import run.halo.app.extension.controller.ControllerManager;
 import run.halo.app.extension.router.ExtensionCompositeRouterFunction;
 import run.halo.app.infra.ExternalUrlSupplier;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
 import run.halo.app.infra.properties.HaloProperties;
 import run.halo.app.plugin.HaloPluginManager;
 import run.halo.app.plugin.resources.JsBundleRuleProvider;
@@ -171,9 +172,11 @@ public class ExtensionConfiguration {
 
         @Bean
         Controller systemSettingController(ExtensionClient client,
+            SystemConfigurableEnvironmentFetcher environmentFetcher,
             ApplicationContext applicationContext) {
             return new ControllerBuilder("system-setting-controller", client)
-                .reconciler(new SystemSettingReconciler(client, applicationContext))
+                .reconciler(new SystemSettingReconciler(client, environmentFetcher,
+                    applicationContext))
                 .extension(new ConfigMap())
                 .build();
         }

src/main/java/run/halo/app/core/extension/reconciler/SystemSettingReconciler.java

@@ -3,13 +3,16 @@ package run.halo.app.core.extension.reconciler;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
 import org.springframework.context.ApplicationContext;
 import run.halo.app.extension.ConfigMap;
 import run.halo.app.extension.ExtensionClient;
+import run.halo.app.extension.Metadata;
 import run.halo.app.extension.controller.Reconciler;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
 import run.halo.app.infra.SystemSetting;
 import run.halo.app.infra.utils.JsonUtils;
 import run.halo.app.infra.utils.PathUtils;
@@ -28,12 +31,16 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
     public static final String FINALIZER_NAME = "system-setting-protection";
 
     private final ExtensionClient client;
+    private final SystemConfigurableEnvironmentFetcher environmentFetcher;
     private final ApplicationContext applicationContext;
 
     private final RouteRuleReconciler routeRuleReconciler = new RouteRuleReconciler();
 
-    public SystemSettingReconciler(ExtensionClient client, ApplicationContext applicationContext) {
+    public SystemSettingReconciler(ExtensionClient client,
+        SystemConfigurableEnvironmentFetcher environmentFetcher,
+        ApplicationContext applicationContext) {
         this.client = client;
+        this.environmentFetcher = environmentFetcher;
         this.applicationContext = applicationContext;
     }
 
@@ -47,11 +54,44 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
             .ifPresent(configMap -> {
                 addFinalizerIfNecessary(configMap);
                 routeRuleReconciler.reconcile(name);
+                customizeSystem(name);
             });
         return new Result(false, null);
     }
 
+    private void customizeSystem(String name) {
+        if (!SystemSetting.SYSTEM_CONFIG_DEFAULT.equals(name)) {
+            return;
+        }
+        // configMap named system not found then create it by system-default
+        Optional<ConfigMap> systemOpt = client.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG);
+        if (systemOpt.isPresent()) {
+            return;
+        }
+        ConfigMap system = client.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG_DEFAULT)
+            .map(configMap -> {
+                // create a new configMap named system by system-default
+                ConfigMap systemConfigMap = new ConfigMap();
+                systemConfigMap.setMetadata(new Metadata());
+                systemConfigMap.getMetadata().setName(SystemSetting.SYSTEM_CONFIG);
+                systemConfigMap.setData(configMap.getData());
+                return systemConfigMap;
+            })
+            .orElseGet(() -> {
+                // empty configMap named system
+                ConfigMap configMap = new ConfigMap();
+                configMap.setMetadata(new Metadata());
+                configMap.getMetadata().setName(SystemSetting.SYSTEM_CONFIG);
+                configMap.setData(new HashMap<>());
+                return configMap;
+            });
+        client.create(system);
+    }
+
     private void addFinalizerIfNecessary(ConfigMap oldConfigMap) {
+        if (SystemSetting.SYSTEM_CONFIG.equals(oldConfigMap.getMetadata().getName())) {
+            return;
+        }
         Set<String> finalizers = oldConfigMap.getMetadata().getFinalizers();
         if (finalizers != null && finalizers.contains(FINALIZER_NAME)) {
             return;
@@ -78,7 +118,7 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
         }
 
         private void reconcileArchivesRule(String name) {
-            client.fetch(ConfigMap.class, name).ifPresent(configMap -> {
+            getConfigMap(name).ifPresent(configMap -> {
                 SystemSetting.ThemeRouteRules oldRules = getOldRouteRulesFromAnno(configMap);
                 SystemSetting.ThemeRouteRules newRules = getRouteRules(configMap);
 
@@ -128,7 +168,7 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
         }
 
         private void reconcileTagsRule(String name) {
-            client.fetch(ConfigMap.class, name).ifPresent(configMap -> {
+            getConfigMap(name).ifPresent(configMap -> {
                 SystemSetting.ThemeRouteRules oldRules = getOldRouteRulesFromAnno(configMap);
                 SystemSetting.ThemeRouteRules newRules = getRouteRules(configMap);
                 final String oldTagsPrefix = oldRules.getTags();
@@ -147,7 +187,7 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
         }
 
         private void reconcileCategoriesRule(String name) {
-            client.fetch(ConfigMap.class, name).ifPresent(configMap -> {
+            getConfigMap(name).ifPresent(configMap -> {
                 SystemSetting.ThemeRouteRules oldRules = getOldRouteRulesFromAnno(configMap);
                 SystemSetting.ThemeRouteRules newRules = getRouteRules(configMap);
                 final String oldCategoriesPrefix = oldRules.getCategories();
@@ -166,7 +206,7 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
         }
 
         private void reconcilePostRule(String name) {
-            client.fetch(ConfigMap.class, name).ifPresent(configMap -> {
+            getConfigMap(name).ifPresent(configMap -> {
                 SystemSetting.ThemeRouteRules oldRules = getOldRouteRulesFromAnno(configMap);
                 SystemSetting.ThemeRouteRules newRules = getRouteRules(configMap);
 
@@ -239,6 +279,11 @@ public class SystemSettingReconciler implements Reconciler<Reconciler.Request> {
     }
 
     public boolean isSystemSetting(String name) {
-        return SystemSetting.SYSTEM_CONFIG.equals(name);
+        return SystemSetting.SYSTEM_CONFIG.equals(name)
+            || SystemSetting.SYSTEM_CONFIG_DEFAULT.equals(name);
+    }
+
+    private Optional<ConfigMap> getConfigMap(String name) {
+        return environmentFetcher.getConfigMapBlocking();
     }
 }

src/main/java/run/halo/app/infra/SystemConfigurableEnvironmentFetcher.java

@@ -1,15 +1,28 @@
 package run.halo.app.infra;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.JsonNodeFactory;
+import com.github.fge.jsonpatch.JsonPatchException;
+import com.github.fge.jsonpatch.mergepatch.JsonMergePatch;
+import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.Optional;
+import org.apache.commons.lang3.StringUtils;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.lang.NonNull;
 import org.springframework.stereotype.Component;
 import reactor.core.publisher.Mono;
 import run.halo.app.extension.ConfigMap;
 import run.halo.app.extension.ReactiveExtensionClient;
+import run.halo.app.infra.utils.JsonParseException;
 import run.halo.app.infra.utils.JsonUtils;
 
 /**
+ * A fetcher that fetches the system configuration from the extension client.
+ * If there are {@link ConfigMap}s named <code>system-default</code> and <code>system</code> at
+ * the same time, the {@link ConfigMap} named system will be json merge patch to
+ * {@link ConfigMap} named <code>system-default</code>
+ *
  * @author guqing
  * @since 2.0.0
  */
@@ -49,7 +62,80 @@ public class SystemConfigurableEnvironmentFetcher {
             .defaultIfEmpty(Map.of());
     }
 
+    /**
+     * Gets config map.
+     *
+     * @return a new {@link ConfigMap} named <code>system</code> by json merge patch.
+     */
     public Mono<ConfigMap> getConfigMap() {
-        return extensionClient.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG);
+        return extensionClient.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG_DEFAULT)
+            .flatMap(systemDefault ->
+                extensionClient.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG)
+                    .map(system -> {
+                        Map<String, String> defaultData = systemDefault.getData();
+                        Map<String, String> data = system.getData();
+                        Map<String, String> mergedData = mergeData(defaultData, data);
+                        system.setData(mergedData);
+                        return system;
+                    })
+                    .switchIfEmpty(Mono.just(systemDefault)));
+    }
+
+    public Optional<ConfigMap> getConfigMapBlocking() {
+        return getConfigMap().blockOptional();
+    }
+
+    private Map<String, String> mergeData(Map<String, String> defaultData,
+        Map<String, String> data) {
+        if (defaultData == null) {
+            return data;
+        }
+        if (data == null) {
+            return defaultData;
+        }
+
+        Map<String, String> copiedDefault = new LinkedHashMap<>(defaultData);
+        // // merge the data map entries into the default map
+        data.forEach((group, dataValue) -> {
+            // https://www.rfc-editor.org/rfc/rfc7386
+            String defaultV = copiedDefault.get(group);
+            String newValue;
+            if (dataValue == null) {
+                if (copiedDefault.containsKey(group)) {
+                    newValue = null;
+                } else {
+                    newValue = defaultV;
+                }
+            } else {
+                newValue = mergeRemappingFunction(dataValue, defaultV);
+            }
+
+            if (newValue == null) {
+                copiedDefault.remove(group);
+            } else {
+                copiedDefault.put(group, newValue);
+            }
+        });
+        return copiedDefault;
+    }
+
+    String mergeRemappingFunction(String dataV, String defaultV) {
+        JsonNode dataJsonValue = nullSafeToJsonNode(dataV);
+        // original
+        JsonNode defaultJsonValue = nullSafeToJsonNode(defaultV);
+        try {
+            // patch
+            JsonMergePatch jsonMergePatch = JsonMergePatch.fromJson(dataJsonValue);
+            // apply patch to original
+            JsonNode patchedNode = jsonMergePatch.apply(defaultJsonValue);
+            return JsonUtils.objectToJson(patchedNode);
+        } catch (JsonPatchException e) {
+            throw new JsonParseException(e);
+        }
+    }
+
+    JsonNode nullSafeToJsonNode(String json) {
+        return StringUtils.isBlank(json) ? JsonNodeFactory.instance.nullNode()
+            : JsonUtils.jsonToObject(json, JsonNode.class);
     }
 }

src/main/java/run/halo/app/infra/SystemSetting.java

@@ -9,6 +9,7 @@ import lombok.Data;
  * @since 2.0.0
  */
 public class SystemSetting {
+    public static final String SYSTEM_CONFIG_DEFAULT = "system-default";
     public static final String SYSTEM_CONFIG = "system";
 
     @Data

src/main/java/run/halo/app/plugin/SettingFetcher.java

@@ -16,7 +16,7 @@ import run.halo.app.infra.utils.JsonParseException;
 import run.halo.app.infra.utils.JsonUtils;
 
 /**
- * <p>A value fetcher for pPlugin form configuration.</p>
+ * <p>A value fetcher for plugin form configuration.</p>
  *
  * @author guqing
  * @since 2.0.0

src/main/java/run/halo/app/theme/router/PermalinkPatternProvider.java

@@ -2,8 +2,7 @@ package run.halo.app.theme.router;
 
 import java.util.Map;
 import org.springframework.stereotype.Component;
-import run.halo.app.extension.ConfigMap;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
-import run.halo.app.extension.ExtensionClient;
 import run.halo.app.infra.SystemSetting;
 import run.halo.app.infra.utils.JsonUtils;
 import run.halo.app.theme.DefaultTemplateEnum;
@@ -18,14 +17,14 @@ import run.halo.app.theme.DefaultTemplateEnum;
 @Component
 public class PermalinkPatternProvider {
 
-    private final ExtensionClient client;
+    private final SystemConfigurableEnvironmentFetcher environmentFetcher;
 
-    public PermalinkPatternProvider(ExtensionClient client) {
+    public PermalinkPatternProvider(SystemConfigurableEnvironmentFetcher environmentFetcher) {
-        this.client = client;
+        this.environmentFetcher = environmentFetcher;
     }
 
     private SystemSetting.ThemeRouteRules getPermalinkRules() {
-        return client.fetch(ConfigMap.class, SystemSetting.SYSTEM_CONFIG)
+        return environmentFetcher.getConfigMapBlocking()
             .map(configMap -> {
                 Map<String, String> data = configMap.getData();
                 return data.get(SystemSetting.ThemeRouteRules.GROUP);

src/main/resources/extensions/system-configurable-configmap.yaml

@@ -1,7 +1,7 @@
 apiVersion: v1alpha1
 kind: "ConfigMap"
 metadata:
-  name: system
+  name: system-default
 data:
   theme: |
     {

src/test/java/run/halo/app/core/extension/endpoint/UserEndpointTest.java

@@ -36,6 +36,7 @@ import run.halo.app.core.extension.service.UserService;
 import run.halo.app.extension.Metadata;
 import run.halo.app.extension.ReactiveExtensionClient;
 import run.halo.app.extension.exception.ExtensionNotFoundException;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
 import run.halo.app.infra.utils.JsonUtils;
 
 @SpringBootTest
@@ -55,6 +56,9 @@ class UserEndpointTest {
     @MockBean
     UserService userService;
 
+    @MockBean
+    SystemConfigurableEnvironmentFetcher environmentFetcher;
+
     @BeforeEach
     void setUp() {
         // disable authorization

src/test/java/run/halo/app/core/extension/reconciler/SystemSettingReconcilerTest.java

@@ -8,7 +8,6 @@ import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.function.Function;
@@ -23,6 +22,7 @@ import run.halo.app.extension.ConfigMap;
 import run.halo.app.extension.ExtensionClient;
 import run.halo.app.extension.Metadata;
 import run.halo.app.extension.controller.Reconciler;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
 import run.halo.app.infra.SystemSetting;
 import run.halo.app.infra.utils.JsonUtils;
 
@@ -41,11 +41,15 @@ class SystemSettingReconcilerTest {
     @Mock
     private ApplicationContext applicationContext;
 
+    @Mock
+    private SystemConfigurableEnvironmentFetcher environmentFetcher;
+
     private SystemSettingReconciler systemSettingReconciler;
 
     @BeforeEach
     void setUp() {
-        systemSettingReconciler = new SystemSettingReconciler(client, applicationContext);
+        systemSettingReconciler = new SystemSettingReconciler(client, environmentFetcher,
+            applicationContext);
     }
 
     @Test
@@ -54,14 +58,14 @@ class SystemSettingReconcilerTest {
             rules.setArchives("archives-new");
             return rules;
         });
+        when(environmentFetcher.getConfigMapBlocking()).thenReturn(Optional.of(configMap));
         when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
             .thenReturn(Optional.of(configMap));
         systemSettingReconciler.reconcile(new Reconciler.Request(SystemSetting.SYSTEM_CONFIG));
         ArgumentCaptor<ConfigMap> captor = ArgumentCaptor.forClass(ConfigMap.class);
-        verify(client, times(2)).update(captor.capture());
+        verify(client, times(1)).update(captor.capture());
 
-        List<ConfigMap> allValues = captor.getAllValues();
+        ConfigMap updatedConfigMap = captor.getValue();
-        ConfigMap updatedConfigMap = allValues.get(1);
         assertThat(rulesFrom(updatedConfigMap).getArchives()).isEqualTo("archives-new");
         assertThat(rulesFrom(updatedConfigMap).getPost()).isEqualTo("/archives-new/{slug}");
 
@@ -78,14 +82,14 @@ class SystemSettingReconcilerTest {
             rules.setTags("tags-new");
             return rules;
         });
+        when(environmentFetcher.getConfigMapBlocking()).thenReturn(Optional.of(configMap));
         when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
             .thenReturn(Optional.of(configMap));
         systemSettingReconciler.reconcile(new Reconciler.Request(SystemSetting.SYSTEM_CONFIG));
         ArgumentCaptor<ConfigMap> captor = ArgumentCaptor.forClass(ConfigMap.class);
-        verify(client, times(2)).update(captor.capture());
+        verify(client, times(1)).update(captor.capture());
 
-        List<ConfigMap> allValues = captor.getAllValues();
+        ConfigMap updatedConfigMap = captor.getValue();
-        ConfigMap updatedConfigMap = allValues.get(1);
         assertThat(rulesFrom(updatedConfigMap).getTags()).isEqualTo("tags-new");
 
         assertThat(oldRulesFromAnno(updatedConfigMap).getTags()).isEqualTo("tags-new");
@@ -99,14 +103,14 @@ class SystemSettingReconcilerTest {
             rules.setCategories("categories-new");
             return rules;
         });
+        when(environmentFetcher.getConfigMapBlocking()).thenReturn(Optional.of(configMap));
         when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
             .thenReturn(Optional.of(configMap));
         systemSettingReconciler.reconcile(new Reconciler.Request(SystemSetting.SYSTEM_CONFIG));
         ArgumentCaptor<ConfigMap> captor = ArgumentCaptor.forClass(ConfigMap.class);
-        verify(client, times(2)).update(captor.capture());
+        verify(client, times(1)).update(captor.capture());
 
-        List<ConfigMap> allValues = captor.getAllValues();
+        ConfigMap updatedConfigMap = captor.getValue();
-        ConfigMap updatedConfigMap = allValues.get(1);
         assertThat(rulesFrom(updatedConfigMap).getCategories()).isEqualTo("categories-new");
 
         assertThat(oldRulesFromAnno(updatedConfigMap).getCategories()).isEqualTo("categories-new");
@@ -120,14 +124,14 @@ class SystemSettingReconcilerTest {
             rules.setPost("/post-new/{slug}");
             return rules;
         });
+        when(environmentFetcher.getConfigMapBlocking()).thenReturn(Optional.of(configMap));
         when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
             .thenReturn(Optional.of(configMap));
         systemSettingReconciler.reconcile(new Reconciler.Request(SystemSetting.SYSTEM_CONFIG));
         ArgumentCaptor<ConfigMap> captor = ArgumentCaptor.forClass(ConfigMap.class);
-        verify(client, times(2)).update(captor.capture());
+        verify(client, times(1)).update(captor.capture());
 
-        List<ConfigMap> allValues = captor.getAllValues();
+        ConfigMap updatedConfigMap = captor.getValue();
-        ConfigMap updatedConfigMap = allValues.get(1);
         assertThat(rulesFrom(updatedConfigMap).getPost()).isEqualTo("/post-new/{slug}");
 
         assertThat(oldRulesFromAnno(updatedConfigMap).getPost()).isEqualTo("/post-new/{slug}");

src/test/java/run/halo/app/infra/SystemConfigurableEnvironmentFetcherTest.java

@@ -0,0 +1,168 @@
+package run.halo.app.infra;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.lenient;
+
+import java.util.LinkedHashMap;
+import org.json.JSONException;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.skyscreamer.jsonassert.JSONAssert;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+import run.halo.app.extension.ConfigMap;
+import run.halo.app.extension.Metadata;
+import run.halo.app.extension.ReactiveExtensionClient;
+import run.halo.app.infra.utils.JsonUtils;
+
+/**
+ * Tests for {@link SystemConfigurableEnvironmentFetcher}.
+ *
+ * @author guqing
+ * @since 2.0.0
+ */
+@ExtendWith(MockitoExtension.class)
+class SystemConfigurableEnvironmentFetcherTest {
+
+    @Mock
+    private ReactiveExtensionClient client;
+
+    @InjectMocks
+    private SystemConfigurableEnvironmentFetcher environmentFetcher;
+
+    @BeforeEach
+    void setUp() {
+        lenient().when(client.fetch(eq(ConfigMap.class), eq("system-default")))
+            .thenReturn(Mono.just(systemDefault()));
+        lenient().when(client.fetch(eq(ConfigMap.class), eq("system")))
+            .thenReturn(Mono.just(system()));
+    }
+
+    @Test
+    void getConfigMap() {
+        environmentFetcher.getConfigMap()
+            .as(StepVerifier::create)
+            .consumeNextWith(configMap -> {
+                assertThat(configMap.getMetadata().getName())
+                    .isEqualTo(SystemSetting.SYSTEM_CONFIG);
+                try {
+                    JSONAssert.assertEquals(expectedJson(),
+                        JsonUtils.objectToJson(configMap),
+                        true);
+                } catch (JSONException e) {
+                    throw new RuntimeException(e);
+                }
+            })
+            .verifyComplete();
+    }
+
+    String expectedJson() {
+        String routeRules =
+            "{\\\"categories\\\":\\\"topics\\\",\\\"archives\\\":\\\"archives-new\\\","
+                + "\\\"post\\\":\\\"/archives-new/{slug}\\\"}";
+        String fakeArray = "{\\\"select\\\":[{\\\"label\\\":\\\"Hello\\\","
+            + "\\\"value\\\":\\\"hello\\\"},{\\\"label\\\":\\\"Awesome\\\","
+            + "\\\"value\\\":\\\"awesome\\\"}]}";
+        return """
+            {
+                "data": {
+                    "routeRules": "%s",
+                    "seo": "{\\"blockSpiders\\":\\"true\\",\\"keywords\\":\\"Hello,Test,Fake\\"}",
+                    "fakeArray": "%s"
+                },
+                "apiVersion": "v1alpha1",
+                "kind": "ConfigMap",
+                "metadata": {
+                    "name": "system"
+                }
+            }
+            """.formatted(routeRules, fakeArray);
+    }
+
+    ConfigMap systemDefault() {
+        ConfigMap configMap = new ConfigMap();
+        configMap.setMetadata(new Metadata());
+        configMap.getMetadata().setName("system-default");
+        configMap.setData(new LinkedHashMap<>());
+        configMap.getData().put("routeRules", """
+            {
+                "categories": "categories",
+                "archives": "archives",
+                "post": "/archives/{slug}",
+                "tags": "tags"
+            }
+            """
+        );
+        configMap.getData().put("seo", """
+            {
+                "blockSpiders": "false",
+                "keywords": "Hello,Test,Fake"
+            }
+            """
+        );
+        configMap.getData().put("post", """
+            {
+                "pageSize": "10"
+            }
+            """
+        );
+        configMap.getData().put("fakeArray", """
+            {
+                "select": [{
+                    "label": "Hello",
+                    "value": "hello"
+                }, {
+                    "label": "Test",
+                    "value": "test"
+                }]
+            }
+            """
+        );
+        return configMap;
+    }
+
+    ConfigMap system() {
+        ConfigMap configMap = new ConfigMap();
+        configMap.setMetadata(new Metadata());
+        configMap.getMetadata().setName("system");
+        configMap.setData(new LinkedHashMap<>());
+        // will delete the tags key and replace some values
+        configMap.getData().put("routeRules", """
+            {
+                "categories": "topics",
+                "archives": "archives-new",
+                "post": "/archives-new/{slug}",
+                "tags": null
+            }
+            """
+        );
+        configMap.getData().put("seo", """
+            {
+                "blockSpiders": "true"
+            }
+            """
+        );
+
+        // deleted post group here
+        configMap.getData().put("post", null);
+
+        configMap.getData().put("fakeArray", """
+            {
+                "select": [{
+                    "label": "Hello",
+                    "value": "hello"
+                }, {
+                    "label": "Awesome",
+                    "value": "awesome"
+                }]
+            }
+            """
+        );
+        return configMap;
+    }
+}

src/test/java/run/halo/app/theme/router/PermalinkPatternProviderTest.java

@@ -1,19 +1,18 @@
 package run.halo.app.theme.router;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.when;
 
 import java.util.Map;
 import java.util.Optional;
-import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 import run.halo.app.extension.ConfigMap;
-import run.halo.app.extension.ExtensionClient;
 import run.halo.app.extension.Metadata;
+import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
 import run.halo.app.infra.SystemSetting;
 import run.halo.app.infra.utils.JsonUtils;
 import run.halo.app.theme.DefaultTemplateEnum;
@@ -28,18 +27,14 @@ import run.halo.app.theme.DefaultTemplateEnum;
 class PermalinkPatternProviderTest {
 
     @Mock
-    private ExtensionClient client;
+    private SystemConfigurableEnvironmentFetcher environmentFetcher;
 
+    @InjectMocks
     private PermalinkPatternProvider permalinkPatternProvider;
 
-    @BeforeEach
-    void setUp() {
-        permalinkPatternProvider = new PermalinkPatternProvider(client);
-    }
-
     @Test
     void getPatternThenDefault() {
-        when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
+        when(environmentFetcher.getConfigMapBlocking())
             .thenReturn(Optional.empty());
 
         String pattern = permalinkPatternProvider.getPattern(DefaultTemplateEnum.POST);
@@ -79,7 +74,7 @@ class PermalinkPatternProviderTest {
 
         configMap.setData(Map.of("routeRules", JsonUtils.objectToJson(themeRouteRules)));
 
-        when(client.fetch(eq(ConfigMap.class), eq(SystemSetting.SYSTEM_CONFIG)))
+        when(environmentFetcher.getConfigMapBlocking())
             .thenReturn(Optional.of(configMap));
 
         String pattern = permalinkPatternProvider.getPattern(DefaultTemplateEnum.POST);