1.grpc的相关知识点,下面先看一遍先
Before you begin
Prerequisites
JDK
: version 7 or higher
Download the example
You’ll need a local copy of the example code to work through this quickstart. Download the example code from our Github repository (the following command clones the entire repository, but you just need the examples for this quickstart and other tutorials):
$ # Clone the repository at the latest release to get the example code:
$ git clone -b v1.13.1 https://github.com/grpc/grpc-java
$ # Navigate to the Java examples:
$ cd grpc-java/examples
Run a gRPC application
From the examples
directory:
Compile the client and server
$ ./gradlew installDist
Run the server
$ ./build/install/examples/bin/hello-world-server
In another terminal, run the client
$ ./build/install/examples/bin/hello-world-client
Congratulations! You’ve just run a client-server application with gRPC.
Update a gRPC service
Now let’s look at how to update the application with an extra method on the server for the client to call. Our gRPC service is defined using protocol buffers; you can find out lots more about how to define a service in a .proto
file in gRPC Basics: Java. For now all you need to know is that both the server and the client “stub” have a SayHello
RPC method that takes a HelloRequest
parameter from the client and returns a HelloReply
from the server, and that this method is defined like this:
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayHello (HelloRequest) returns (HelloReply) {}
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings
message HelloReply {
string message = 1;
}
Let’s update this so that the Greeter
service has two methods. Editsrc/main/proto/helloworld.proto
and update it with a new SayHelloAgain
method, with the same request and response types:
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayHello (HelloRequest) returns (HelloReply) {}
// Sends another greeting
rpc SayHelloAgain (HelloRequest) returns (HelloReply) {}
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings
message HelloReply {
string message = 1;
}
(Don’t forget to save the file!)
Update and run the application
When we recompile the example, normal compilation will regenerate GreeterGrpc.java
, which contains our generated gRPC client and server classes. This also regenerates classes for populating, serializing, and retrieving our request and response types.
However, we still need to implement and call the new method in the human-written parts of our example application.
Update the server
In the same directory, opensrc/main/java/io/grpc/examples/helloworld/HelloWorldServer.java
. Implement the new method like this:
private class GreeterImpl extends GreeterGrpc.GreeterImplBase {
@Override
public void sayHello(HelloRequest req, StreamObserver<HelloReply> responseObserver) {
HelloReply reply = HelloReply.newBuilder().setMessage("Hello " + req.getName()).build();
responseObserver.onNext(reply);
responseObserver.onCompleted();
}
@Override
public void sayHelloAgain(HelloRequest req, StreamObserver<HelloReply> responseObserver) {
HelloReply reply = HelloReply.newBuilder().setMessage("Hello again " + req.getName()).build();
responseObserver.onNext(reply);
responseObserver.onCompleted();
}
}
...
Update the client
In the same directory, opensrc/main/java/io/grpc/examples/helloworld/HelloWorldClient.java
. Call the new method like this:
public void greet(String name) {
logger.info("Will try to greet " + name + " ...");
HelloRequest request = HelloRequest.newBuilder().setName(name).build();
HelloReply response;
try {
response = blockingStub.sayHello(request);
} catch (StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}
logger.info("Greeting: " + response.getMessage());
try {
response = blockingStub.sayHelloAgain(request);
} catch (StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}
logger.info("Greeting: " + response.getMessage());
}
Run!
Just like we did before, from the examples
directory:
Compile the client and server
$ ./gradlew installDist
Run the server
$ ./build/install/examples/bin/hello-world-server
In another terminal, run the client
$ ./build/install/examples/bin/hello-world-client
2.编写grpc-client的代码
根据定义的grpc的proto的文件,自动回生成代码,主要是grpc的基本包。里面包括grpc,stub,service服务等;
3.需要相关的lib库的依赖包,grpc工程包lib库。我建1.6.1的lib库整体放到了工程库中。方便调用;
4.自己编写了一个gis-client的包进行grpc调用;
调试的例子为:代码出现这个说明grpc调通成功;
5.集成到ngrinder的grpc的代码;
将jar上传到lib目录中。groovy引入,直接在@test里面调用就可以了;