grpc.io/content/en/docs/languages/php/quickstart.md

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---
title: Quick start
description: This guide gets you started with gRPC in PHP with a simple working example.
weight: 10
spelling: cSpell:ignore autogen chmod devel PECL phar phpize phpunit RHEL
---
### Prerequisites
- PHP 7.0 or higher, PECL, Composer
- grpc extension, protocol buffers compiler: for installation instructions, see
the [gRPC PHP readme][].
### Get the example code
The example code is part of the [grpc][] repo.
{{% alert title="Note" color="info" %}}
You can only create gRPC clients in PHP. Use [another
language](/docs/languages/) to create a gRPC server.
{{% /alert %}}
1. Clone the [grpc][] repo and its submodules:
```sh
git clone --recurse-submodules -b {{< param grpc_vers.core >}} --depth 1 --shallow-submodules https://github.com/grpc/grpc
```
2. Change to the quick start example directory:
```sh
cd grpc/examples/php
```
3. Install the `grpc` composer package:
```sh
./greeter_proto_gen.sh
composer install
```
### Run the example
1. Launch the quick start server: for example, follow the instructions given
in the [Quick start for Node][].
2. From the `examples/php` directory, run the PHP client:
```sh
./run_greeter_client.sh
```
Congratulations! You've just run a client-server application with gRPC.
### Update the 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 [Basics tutorial][]. 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 `HelloResponse` from
the server, and that this method is defined like this:
```protobuf
// 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. Edit
`examples/protos/helloworld.proto` and update it with a new `SayHelloAgain`
method, with the same request and response types:
```protobuf
// 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;
}
```
Remember to save the file!
### Regenerate gRPC code
Next we need to update the gRPC code used by our application to use the new
service definition. From the `grpc` root directory:
```sh
protoc --proto_path=examples/protos \
--php_out=examples/php \
--grpc_out=examples/php \
--plugin=protoc-gen-grpc=bins/opt/grpc_php_plugin \
./examples/protos/helloworld.proto
```
or running the helper script under the `grpc/example/php` directory if you build
grpc-php-plugin by source:
```sh
./greeter_proto_gen.sh
```
This regenerates the protobuf files, which contain our generated client classes,
as well as classes for populating, serializing, and retrieving our request and
response types.
### Update and run the application
We now have new generated client code, but 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, open `greeter_server.js`. Implement the new method like
this:
```js
function sayHello(call, callback) {
callback(null, {message: 'Hello ' + call.request.name});
}
function sayHelloAgain(call, callback) {
callback(null, {message: 'Hello again, ' + call.request.name});
}
function main() {
var server = new grpc.Server();
server.addProtoService(hello_proto.Greeter.service,
{sayHello: sayHello, sayHelloAgain: sayHelloAgain});
server.bind('0.0.0.0:50051', grpc.ServerCredentials.createInsecure());
server.start();
}
...
```
#### Update the client
In the same directory, open `greeter_client.php`. Call the new method like this:
```php
$request = new Helloworld\HelloRequest();
$request->setName($name);
list($reply, $status) = $client->SayHello($request)->wait();
$message = $reply->getMessage();
list($reply, $status) = $client->SayHelloAgain($request)->wait();
$message = $reply->getMessage();
```
#### Run!
Just like we did before, from the `grpc-node/examples/helloworld/dynamic_codegen` directory:
1. Run the server:
```sh
node greeter_server.js
```
2. From another terminal, from the `examples/php` directory,
run the client:
```sh
./run_greeter_client.sh
```
### What's next
- Learn how gRPC works in [Introduction to gRPC](/docs/what-is-grpc/introduction/)
and [Core concepts](/docs/what-is-grpc/core-concepts/).
- Work through the [Basics tutorial][].
- Explore the [API reference](../api).
[Basics tutorial]: {{< relref "basics" >}}
[gRPC PHP readme]: https://github.com/grpc/grpc/blob/{{< param grpc_vers.core >}}/src/php/README.md
[grpc]: https://github.com/grpc/grpc
[Quick start for Node]: {{< relref "/docs/languages/node/quickstart" >}}