feat: add support for HTTP+JSON/REST

Signed-off-by: Emmanuel Hugonnet <[email protected]>

Author: ehsavoie

pom.xml

@@ -197,6 +197,11 @@
                 <artifactId>a2a-java-sdk-reference-jsonrpc</artifactId>
                 <version>${project.version}</version>
             </dependency>
+            <dependency>
+                <groupId>${project.groupId}</groupId>
+                <artifactId>a2a-java-sdk-transport-httprest</artifactId>
+                <version>${project.version}</version>
+            </dependency>
         </dependencies>
     </dependencyManagement>
 
@@ -322,6 +327,7 @@
         <module>tests/server-common</module>
         <module>transport/jsonrpc</module>
         <module>transport/grpc</module>
+        <module>transport/httprest</module>
     </modules>
 
     <profiles>

server-common/src/main/java/io/a2a/server/requesthandlers/DefaultRequestHandler.java

@@ -44,6 +44,7 @@
 import io.a2a.spec.StreamingEventKind;
 import io.a2a.spec.Task;
 import io.a2a.spec.TaskIdParams;
+import io.a2a.spec.TaskListParams;
 import io.a2a.spec.TaskNotFoundError;
 import io.a2a.spec.TaskPushNotificationConfig;
 import io.a2a.spec.TaskQueryParams;
@@ -114,6 +115,12 @@ public Task onGetTask(TaskQueryParams params, ServerCallContext context) throws
         return task;
     }
 
+    @Override
+    public List<Task> onListTasks(TaskListParams params, ServerCallContext context) throws JSONRPCError {
+        LOGGER.debug("onListTasks");
+        return taskStore.listAll();
+    }
+
     @Override
     public Task onCancelTask(TaskIdParams params, ServerCallContext context) throws JSONRPCError {
         Task task = taskStore.get(params.id());

server-common/src/main/java/io/a2a/server/requesthandlers/RequestHandler.java

@@ -14,13 +14,18 @@
 import io.a2a.spec.Task;
 import io.a2a.spec.TaskIdParams;
 import io.a2a.spec.TaskPushNotificationConfig;
+import io.a2a.spec.TaskListParams;
 import io.a2a.spec.TaskQueryParams;
 
 public interface RequestHandler {
     Task onGetTask(
             TaskQueryParams params,
             ServerCallContext context) throws JSONRPCError;
 
+    List<Task> onListTasks(
+            TaskListParams params,
+            ServerCallContext context) throws JSONRPCError;
+
     Task onCancelTask(
             TaskIdParams params,
             ServerCallContext context) throws JSONRPCError;

server-common/src/main/java/io/a2a/server/tasks/InMemoryTaskStore.java

@@ -1,7 +1,9 @@
 package io.a2a.server.tasks;
 
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
@@ -29,4 +31,9 @@ public Task get(String taskId) {
     public void delete(String taskId) {
         tasks.remove(taskId);
     }
+
+    @Override
+    public List<Task> listAll() {
+        return new ArrayList<>(tasks.values());
+    }
 }

server-common/src/main/java/io/a2a/server/tasks/TaskStore.java

@@ -1,5 +1,7 @@
 package io.a2a.server.tasks;
 
+import java.util.List;
+
 import io.a2a.spec.Task;
 
 public interface TaskStore {
@@ -8,4 +10,6 @@ public interface TaskStore {
     Task get(String taskId);
 
     void delete(String taskId);
+
+    List<Task> listAll();
 }

spec/src/main/java/io/a2a/spec/TaskListParams.java

@@ -0,0 +1,18 @@
+package io.a2a.spec;
+
+import java.util.Map;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+/**
+ * Parameters for listing tasks.
+ */
+@JsonInclude(JsonInclude.Include.NON_ABSENT)
+@JsonIgnoreProperties(ignoreUnknown = true)
+public record TaskListParams(Map<String, Object> metadata) {
+
+    public TaskListParams() {
+        this(null);
+    }
+}

transport/httprest/pom.xml

@@ -0,0 +1,54 @@
+<?xml version="1.0"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>io.github.a2asdk</groupId>
+        <artifactId>a2a-java-sdk-parent</artifactId>
+        <version>0.3.0.Beta1-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+    <artifactId>a2a-java-sdk-transport-httprest</artifactId>
+
+    <packaging>jar</packaging>
+
+    <name>Java SDK A2A Transport: HTTP+JSON/REST</name>
+    <description>Java SDK for the Agent2Agent Protocol (A2A) - HTTP+JSON/REST Transport</description>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.github.a2asdk</groupId>
+            <artifactId>a2a-java-sdk-server-common</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>a2a-java-sdk-server-common</artifactId>
+            <version>${project.version}</version>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.datatype</groupId>
+            <artifactId>jackson-datatype-jsr310</artifactId>
+        </dependency>
+
+    </dependencies>
+    
+</project>