feat(webflux): enhance command message parsing with customizable header appender

- Introduce CommandRequestHeaderAppender interface for flexible header handling
- Implement CommandRequestExtendHeaderAppender for extended headers
- Update DefaultCommandMessageParser to use CommandRequestHeaderAppender
- Add commandRequestExtendHeaderAppender bean in WebFluxAutoConfiguration
- Modify commandMessageParser bean to accept CommandRequestHeaderAppender

Author: Ahoo-Wang

wow-spring-boot-starter/src/main/kotlin/me/ahoo/wow/spring/boot/starter/webflux/WebFluxAutoConfiguration.kt

@@ -38,6 +38,8 @@ import me.ahoo.wow.webflux.route.bi.GenerateBIScriptHandlerFunctionFactory
 import me.ahoo.wow.webflux.route.command.CommandFacadeHandlerFunctionFactory
 import me.ahoo.wow.webflux.route.command.CommandHandlerFunctionFactory
 import me.ahoo.wow.webflux.route.command.CommandMessageParser
+import me.ahoo.wow.webflux.route.command.CommandRequestExtendHeaderAppender
+import me.ahoo.wow.webflux.route.command.CommandRequestHeaderAppender
 import me.ahoo.wow.webflux.route.command.DEFAULT_TIME_OUT
 import me.ahoo.wow.webflux.route.command.DefaultCommandMessageParser
 import me.ahoo.wow.webflux.route.event.CountEventStreamHandlerFunctionFactory
@@ -141,10 +143,21 @@ class WebFluxAutoConfiguration {
         return GlobalExceptionHandler
     }
 
+    @Bean
+    fun commandRequestExtendHeaderAppender(): CommandRequestExtendHeaderAppender {
+        return CommandRequestExtendHeaderAppender
+    }
+
     @Bean
     @ConditionalOnMissingBean
-    fun commandMessageParser(commandMessageFactory: CommandMessageFactory): CommandMessageParser {
-        return DefaultCommandMessageParser(commandMessageFactory)
+    fun commandMessageParser(
+        commandMessageFactory: CommandMessageFactory,
+        commandRequestHeaderAppenderObjectProvider: ObjectProvider<CommandRequestHeaderAppender>
+    ): CommandMessageParser {
+        return DefaultCommandMessageParser(
+            commandMessageFactory = commandMessageFactory,
+            commandRequestHeaderAppends = commandRequestHeaderAppenderObjectProvider.toList<CommandRequestHeaderAppender>()
+        )
     }
 
     @Bean

wow-webflux/src/main/kotlin/me/ahoo/wow/webflux/route/command/CommandMessageParser.kt

@@ -15,13 +15,13 @@ package me.ahoo.wow.webflux.route.command
 
 import me.ahoo.wow.api.command.CommandMessage
 import me.ahoo.wow.command.CommandOperator.withOperator
-import me.ahoo.wow.command.factory.CommandBuilder
 import me.ahoo.wow.command.factory.CommandBuilder.Companion.commandBuilder
 import me.ahoo.wow.command.factory.CommandMessageFactory
 import me.ahoo.wow.infra.ifNotBlank
 import me.ahoo.wow.messaging.withLocalFirst
 import me.ahoo.wow.modeling.matedata.AggregateMetadata
-import me.ahoo.wow.openapi.command.CommandRequestHeaders
+import me.ahoo.wow.openapi.command.CommandRequestHeaders.AGGREGATE_VERSION
+import me.ahoo.wow.openapi.command.CommandRequestHeaders.REQUEST_ID
 import org.springframework.web.reactive.function.server.ServerRequest
 import reactor.core.publisher.Mono
 
@@ -33,23 +33,28 @@ interface CommandMessageParser {
     ): Mono<CommandMessage<Any>>
 }
 
-class DefaultCommandMessageParser(private val commandMessageFactory: CommandMessageFactory) : CommandMessageParser {
+class DefaultCommandMessageParser(
+    private val commandMessageFactory: CommandMessageFactory,
+    private val commandRequestHeaderAppends: List<CommandRequestHeaderAppender> = listOf()
+) : CommandMessageParser {
     override fun parse(
         aggregateMetadata: AggregateMetadata<*, *>,
         commandBody: Any,
         request: ServerRequest
     ): Mono<CommandMessage<Any>> {
         val aggregateId = request.getAggregateId()
         val tenantId = request.getTenantId(aggregateMetadata)
-        val aggregateVersion = request.headers().firstHeader(CommandRequestHeaders.AGGREGATE_VERSION)?.toIntOrNull()
-        val requestId = request.headers().firstHeader(CommandRequestHeaders.REQUEST_ID).ifNotBlank { it }
+        val aggregateVersion = request.headers().firstHeader(AGGREGATE_VERSION)?.toIntOrNull()
+        val requestId = request.headers().firstHeader(REQUEST_ID).ifNotBlank { it }
         val commandBuilder = commandBody.commandBuilder()
             .aggregateId(aggregateId)
             .tenantId(tenantId)
             .aggregateVersion(aggregateVersion)
             .requestId(requestId)
             .namedAggregate(aggregateMetadata.namedAggregate)
-        injectExtensionHeaders(commandBuilder, request)
+        commandRequestHeaderAppends.forEach {
+            it.append(request, commandBuilder)
+        }
         request.getLocalFirst()?.let {
             commandBuilder.header { header ->
                 header.withLocalFirst(it)
@@ -63,18 +68,4 @@ class DefaultCommandMessageParser(private val commandMessageFactory: CommandMess
             commandMessageFactory.create<Any>(commandBuilder)
         )
     }
-
-    private fun injectExtensionHeaders(commandBuilder: CommandBuilder, request: ServerRequest) {
-        val extendedHeaders = request.headers().asHttpHeaders()
-            .filter { (key, _) -> key.startsWith(CommandRequestHeaders.COMMAND_HEADER_X_PREFIX) }
-            .map { (key, value) ->
-                key.substring(CommandRequestHeaders.COMMAND_HEADER_X_PREFIX.length) to value.firstOrNull<String>().orEmpty()
-            }.toMap<String, String>()
-        if (extendedHeaders.isEmpty()) {
-            return
-        }
-        commandBuilder.header { header ->
-            header.with(extendedHeaders)
-        }
-    }
 }

wow-webflux/src/main/kotlin/me/ahoo/wow/webflux/route/command/CommandRequestHeaderAppender.kt

@@ -0,0 +1,38 @@
+/*
+ * Copyright [2021-present] [ahoo wang <[email protected]> (https://github.com/Ahoo-Wang)].
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package me.ahoo.wow.webflux.route.command
+
+import me.ahoo.wow.command.factory.CommandBuilder
+import me.ahoo.wow.openapi.command.CommandRequestHeaders.COMMAND_HEADER_X_PREFIX
+import org.springframework.web.reactive.function.server.ServerRequest
+
+interface CommandRequestHeaderAppender {
+    fun append(request: ServerRequest, commandBuilder: CommandBuilder)
+}
+
+object CommandRequestExtendHeaderAppender : CommandRequestHeaderAppender {
+    override fun append(request: ServerRequest, commandBuilder: CommandBuilder) {
+        val extendedHeaders = request.headers().asHttpHeaders()
+            .filter { (key, _) -> key.startsWith(COMMAND_HEADER_X_PREFIX) }
+            .map { (key, value) ->
+                key.substring(COMMAND_HEADER_X_PREFIX.length) to value.firstOrNull<String>().orEmpty()
+            }.toMap<String, String>()
+        if (extendedHeaders.isEmpty()) {
+            return
+        }
+        commandBuilder.header { header ->
+            header.with(extendedHeaders)
+        }
+    }
+}

wow-webflux/src/test/kotlin/me/ahoo/wow/webflux/route/command/DefaultCommandMessageParserTest.kt

@@ -35,7 +35,6 @@ class DefaultCommandMessageParserTest {
             every { principal() } returns Mono.empty()
             every { headers().firstHeader(CommandRequestHeaders.WAIT_STAGE) } returns CommandStage.SENT.toString()
             every { headers().firstHeader(CommandRequestHeaders.LOCAL_FIRST) } returns false.toString()
-            every { headers().asHttpHeaders() } returns HttpHeaders()
         }
         val commandMessageParser =
             DefaultCommandMessageParser(SimpleCommandMessageFactory((SimpleCommandBuilderRewriterRegistry())))
@@ -76,7 +75,12 @@ class DefaultCommandMessageParserTest {
             )
         }
         val commandMessageParser =
-            DefaultCommandMessageParser(SimpleCommandMessageFactory((SimpleCommandBuilderRewriterRegistry())))
+            DefaultCommandMessageParser(
+                SimpleCommandMessageFactory((SimpleCommandBuilderRewriterRegistry())),
+                listOf(
+                    CommandRequestExtendHeaderAppender
+                )
+            )
         commandMessageParser.parse(
             aggregateMetadata = MOCK_AGGREGATE_METADATA,
             commandBody = MockCreateAggregate(