Decipher the principle of vehicle SOA architecture and build the core technology of vehicle communication

Vehicle SOA Architecture Principles

Vehicle SOA architecture (Service-Oriented Architecture, Service-Oriented Architecture) is a design concept aimed at building scalable, flexible and maintainable vehicle systems. The following are some principles and characteristics of the vehicle SOA architecture:

• Service-oriented: The vehicle-mounted SOA architecture divides the vehicle-mounted system into multiple autonomous services, and each service provides specific functions and service interfaces. These services communicate and interact in a loosely coupled manner.
• Service reusability: Services can be reused by multiple applications or modules in the vehicle system. By encapsulating specific functions as reusable services, in-vehicle systems can improve development efficiency and system flexibility.
• Service autonomy: Each service is autonomous and has independent business logic and data. This allows services to be independently developed, tested, deployed, and upgraded without impacting other services.
• Service discovery and binding: The vehicle-mounted SOA architecture uses a service registration and discovery mechanism, enabling services to be dynamically discovered and bound. In this way, services can be dynamically invoked and combined when the system is running, improving the flexibility and scalability of the system.
• Service orchestration and composition: The vehicle-mounted SOA architecture implements complex functions and business processes through service orchestration and composition. Different services can be combined to meet the needs of the in-vehicle system.
• Loose coupling and substitutability: The vehicle-mounted SOA architecture achieves decoupling between services through loosely coupled service interfaces and protocols. This way, the system can easily replace and upgrade services without impacting other services.
• Scalability and modularity: The vehicle-mounted SOA architecture allows the system to expand horizontally and vertically according to requirements. New services can be added to the system without affecting existing services.

SOA vehicle cross-system communication

In the vehicle-mounted system, the inter-system communication is realized through the inter-service communication in the SOA architecture. The following are some common approaches and techniques used to implement SOA in-vehicle cross-system communication:

1. Service call: Various services in the vehicle system can communicate through service calls. Each service exposes its own service interface, and other services can request the function or data of the service by calling the interface method.
2. Messaging: Services in an in-vehicle system can communicate using message passing. Messages can be asynchronous and can carry information such as data and instructions. Common messaging technologies include message queues, message buses, and publish-subscribe patterns.
3. Remote Procedure Call (RPC): RPC is a common cross-system communication mechanism that allows services in an on-board system to call methods of other services in remote systems, just like calling local services. The RPC framework can handle the underlying communication and serialization, making communication between services simple and transparent.
4. Web services: Services in in-vehicle systems can communicate based on web services standards such as SOAP or REST. Interoperability and cross-platform support can be achieved between different systems by defining service interfaces and using standard Web protocols for communication.
5. Data transfer: In addition to service invocation and messaging, services in in-vehicle systems can communicate across systems by sharing data. This can include things like using a shared database, a distributed cache, or a shared file system.
6. Event-driven architecture: Event-driven architecture can be used for decoupling and event delivery in cross-system communication. When a certain event occurs in one system, it can publish the event and notify other systems, and other systems can subscribe to these events and respond accordingly.

SOA in-vehicle cross-system communication practice

Suppose there are two in-vehicle system services: navigation service and audio entertainment service. The navigation service wants to send a command to the audio entertainment service to pause music playback.

1. Define the interface of the navigation service:

// NavigationService.java
public interface NavigationService {
    void sendPauseCommand();
}

1. Navigation service implementation:

// NavigationServiceImpl.java
public class NavigationServiceImpl implements NavigationService {
    private MessageBus messageBus; // 假设有一个消息总线实现
​
    @Override
    public void sendPauseCommand() {
        // 创建消息对象
        Message message = new Message("音频娱乐服务", "暂停音乐播放");
​
        // 将消息发布到消息总线
        messageBus.publishMessage(message);
    }
}

1. The audio entertainment service receives the message and acts accordingly:

// AudioPlayerService.java
public class AudioPlayerService {
    private MessageBus messageBus; // 假设有一个消息总线实现
​
    public void startListening() {
        // 订阅来自导航服务的消息
        messageBus.subscribe("音频娱乐服务", (message) -> {
            if (message.getCommand().equals("暂停音乐播放")) {
                pauseMusic();
            }
        });
    }
​
    private void pauseMusic() {
        // 执行暂停音乐的操作
        System.out.println("音频娱乐服务：暂停音乐播放");
    }
}

In actual situations, it is necessary to view and select available communication frameworks or technical tools in the vehicle system, such as message buses, RPC frameworks, or communication protocols specifically for the vehicle field. The above example provides a simple implementation based on message passing, and you can write code implementations suitable for your specific scenarios according to actual needs and technical choices. At the same time, in order to achieve real cross-system communication, ensure that the network connection and communication protocol settings between services are correct.

SOA Architecture Communication in Automotive

In the automotive domain, SOA (Service Oriented Architecture) can be used to enable communication within the vehicle and between the vehicle and external systems. SOA architecture divides the system into independent services and communicates through defined interfaces and protocols. Following are some common scenarios and techniques for communication using SOA architecture in the automotive domain:

1. CAN (Controller Area Network) bus: CAN bus is a communication protocol widely used in the automotive field, which supports distributed and real-time communication. In the SOA architecture, each in-vehicle system can be used as an independent service and interact through the CAN bus. Each service can send and receive information, such as sensor data, control commands, etc., via CAN messages.
2. Automotive Ethernet: With the increasing complexity of modern automotive electronic systems, more and more car manufacturers use Ethernet as the infrastructure for internal communication in vehicles. In the SOA-based architecture, various systems inside the car can communicate through the Ethernet network. By defining service interfaces and message protocols, different systems can interact and share data.
3. MQTT (Message Queuing Telemetry Transport): MQTT is a lightweight messaging protocol for communication between sensors and devices. In the automotive field, MQTT can be used as a communication protocol between in-vehicle systems. Each system can publish and subscribe to specific topics and communicate through messages. This method can realize functions such as real-time data transmission, event notification and remote command control.
4. RPC (Remote Procedure Call) framework: The RPC framework supports remote calls between systems, and can be used in the SOA architecture to implement communication between services. By defining service interfaces and method call protocols, different services can directly call each other's methods and pass data and parameters. Common RPC frameworks such as gRPC and Apache Thrift also have corresponding customized implementations in the automotive field.

These technologies and solutions are just some examples of using SOA architecture for communication in the automotive field. The specific implementation and selected technologies depend on specific application scenarios, system requirements, and vendor choices. In practice, automakers and suppliers usually choose suitable communication solutions according to specific requirements and standards to build the SOA architecture inside the vehicle.

Practical example of SOA architecture communication in Automotive

In the automotive domain, communicating using an SOA architecture involves multiple components and technologies. The following is a simple example that demonstrates how to use the gRPC framework to communicate between services in the car:

# proto文件
# 定义服务接口和消息
syntax = "proto3";
​
package automotive;
​
service EngineService {
  rpc StartEngine(EngineRequest) returns (EngineResponse) {}
}
​
message EngineRequest {
  string command = 1;
}
​
message EngineResponse {
  string status = 1;
}
​
# 服务实现代码
# 实现EngineService接口的服务
import grpc
from concurrent import futures
import time
​
import automotive_pb2
import automotive_pb2_grpc
​
class EngineServiceServicer(automotive_pb2_grpc.EngineServiceServicer):
    def StartEngine(self, request, context):
        # 根据请求执行对应的操作，这里简单返回状态消息
        response = automotive_pb2.EngineResponse()
        response.status = "Engine started successfully"
        return response
​
# 创建gRPC服务器
def run_server():
    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
    automotive_pb2_grpc.add_EngineServiceServicer_to_server(EngineServiceServicer(), server)
    server.add_insecure_port('[::]:50051')
    server.start()
    print("Server started.")
  
    try:
        while True:
            time.sleep(86400)
    except KeyboardInterrupt:
        server.stop(0)
​
# 客户端代码
# 使用gRPC客户端调用服务
import grpc
import automotive_pb2
import automotive_pb2_grpc
​
def run_client():
    channel = grpc.insecure_channel('localhost:50051')
    stub = automotive_pb2_grpc.EngineServiceStub(channel)
  
    # 创建请求
    request = automotive_pb2.EngineRequest()
    request.command = "start"
​
    # 调用服务
    response = stub.StartEngine(request)
  
    # 处理响应
    print(response.status)
​
if __name__ == '__main__':
    # 启动服务器
    run_server()
​
    # 启动客户端
    run_client()

Note that this is just a simple sample code to demonstrate how to use the gRPC framework to communicate between services inside the car. The actual SOA architecture communication involves more components and technology choices, and the specific implementation will vary with vendors and application scenarios. This article briefly analyzes the communication technology of the vehicle SOA architecture in "Vehicle Development Technology" . For more in-depth learning on the vehicle, you can click the reference to view the detailed categories.

End of article

In-vehicle SOA architecture communication refers to the use of service-oriented architecture (SOA) principles for communication in in-vehicle systems. In the in-vehicle environment, various car internal systems and external systems (such as cloud services, mobile applications, etc.) can communicate and exchange information through defined service interfaces and protocols.

In vehicle SOA architecture communication, each vehicle system is divided into independent service modules, and each module is responsible for a specific function or task. These service modules define interaction methods through standardized interfaces, and perform data sharing and collaborative work through message passing.

Generally, in-vehicle SOA architecture communication can involve the following aspects:

1. Inter-system communication: Various in-vehicle systems (such as engine management system, infotainment system, safety system, etc.) can communicate as independent service modules through defined interfaces and protocols. For example, a safety system could send an alert message to the engine management system, or an infotainment system could request real-time data from the vehicle.
2. External system communication: On-board systems can communicate with external systems, such as exchanging data with cloud services or mobile applications. By defining appropriate interfaces and protocols, the on-board system can perform data transmission, command control and other operations with external systems. For example, vehicles can be connected with mobile apps on smartphones for remote vehicle control, location tracking, and more.
3. Data sharing and collaborative work: Through in-vehicle SOA architecture communication, different in-vehicle systems can share data and work together. For example, the engine management system can share vehicle sensor data with the infotainment system for display or analysis; or the navigation system can share location information with the safety system for intelligent safety warning functions.

Vehicle SOA architecture communication can be realized with the help of different communication technologies and protocols, such as CAN bus, Automotive Ethernet, MQTT, etc. The specific technology selected depends on factors such as system architecture, performance requirements, and data transmission requirements. Importantly, in-vehicle SOA architecture communication provides a modular, flexible and scalable way to enable vehicle internal and external systems to communicate with each other, collaborate and provide a better user experience.