diff options
Diffstat (limited to 'examples/ruby')
| -rw-r--r-- | examples/ruby/.gitignore | 15 | ||||
| -rw-r--r-- | examples/ruby/Gemfile | 6 | ||||
| -rw-r--r-- | examples/ruby/README.md | 61 | ||||
| -rwxr-xr-x | examples/ruby/greeter_client.rb | 50 | ||||
| -rwxr-xr-x | examples/ruby/greeter_server.rb | 60 | ||||
| -rw-r--r-- | examples/ruby/grpc-demo.gemspec | 23 | ||||
| -rw-r--r-- | examples/ruby/lib/helloworld.rb | 18 | ||||
| -rw-r--r-- | examples/ruby/lib/helloworld_services.rb | 24 | ||||
| -rw-r--r-- | examples/ruby/lib/route_guide.rb | 37 | ||||
| -rw-r--r-- | examples/ruby/lib/route_guide_services.rb | 27 | ||||
| -rw-r--r-- | examples/ruby/route_guide/README.md | 285 | ||||
| -rwxr-xr-x | examples/ruby/route_guide/route_guide_client.rb | 165 | ||||
| -rwxr-xr-x | examples/ruby/route_guide/route_guide_server.rb | 211 |
13 files changed, 982 insertions, 0 deletions
diff --git a/examples/ruby/.gitignore b/examples/ruby/.gitignore new file mode 100644 index 0000000000..62fcb4fa94 --- /dev/null +++ b/examples/ruby/.gitignore @@ -0,0 +1,15 @@ +/.bundle/ +/.yardoc +/Gemfile.lock +/_yardoc/ +/coverage/ +/doc/ +/pkg/ +/spec/reports/ +/tmp/ +*.bundle +*.so +*.o +*.a +mkmf.log +vendor diff --git a/examples/ruby/Gemfile b/examples/ruby/Gemfile new file mode 100644 index 0000000000..65d3f0ad4a --- /dev/null +++ b/examples/ruby/Gemfile @@ -0,0 +1,6 @@ +# -*- ruby -*- +# encoding: utf-8 + +source 'https://rubygems.org/' + +gem 'grpc', :git => 'https://github.com/grpc/grpc.git', :submodules => true, glob: 'src/ruby/*.gemspec' diff --git a/examples/ruby/README.md b/examples/ruby/README.md new file mode 100644 index 0000000000..dc21f5dd49 --- /dev/null +++ b/examples/ruby/README.md @@ -0,0 +1,61 @@ +gRPC in 3 minutes (Ruby) +======================== + +BACKGROUND +------------- +For this sample, we've already generated the server and client stubs from [helloworld.proto][] + +PREREQUISITES +------------- + +- Ruby 2.x +This requires Ruby 2.x, as the gRPC API surface uses keyword args. +If you don't have that installed locally, you can use [RVM][] to use Ruby 2.x for testing without upgrading the version of Ruby on your whole system. +RVM is also useful if you don't have the necessary privileges to update your system's Ruby. + + ```sh + $ # RVM installation as specified at https://rvm.io/rvm/install + $ gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 + $ \curl -sSL https://get.rvm.io | bash -s stable --ruby=ruby-2 + $ + $ # follow the instructions to ensure that your're using the latest stable version of Ruby + $ # and that the rvm command is installed + ``` +- *N.B* Make sure your run `source $HOME/.rvm/scripts/rvm` as instructed to complete the set-up of RVM. + +INSTALL +------- + +- Clone this repository +- Use bundler to install the example package's dependencies + + ```sh + $ # from this directory + $ gem install bundler # if you don't already have bundler available + $ bundle install + ``` + +Try it! +------- + +- Run the server + + ```sh + $ # from this directory + $ bundle exec ./greeter_server.rb & + ``` + +- Run the client + + ```sh + $ # from this directory + $ bundle exec ./greeter_client.rb + ``` + +Tutorial +-------- + +You can find a more detailed tutorial in [gRPC Basics: Ruby](examples/ruby/route_guide/README.md) + +[helloworld.proto]:examples/protos/helloworld.proto +[RVM]:https://www.rvm.io/ diff --git a/examples/ruby/greeter_client.rb b/examples/ruby/greeter_client.rb new file mode 100755 index 0000000000..e6cb4bad33 --- /dev/null +++ b/examples/ruby/greeter_client.rb @@ -0,0 +1,50 @@ +#!/usr/bin/env ruby + +# Copyright 2015, Google Inc. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +# Sample app that connects to a Greeter service. +# +# Usage: $ path/to/greeter_client.rb + +this_dir = File.expand_path(File.dirname(__FILE__)) +lib_dir = File.join(this_dir, 'lib') +$LOAD_PATH.unshift(lib_dir) unless $LOAD_PATH.include?(lib_dir) + +require 'grpc' +require 'helloworld_services' + +def main + stub = Helloworld::Greeter::Stub.new('localhost:50051') + user = ARGV.size > 0 ? ARGV[0] : 'world' + message = stub.say_hello(Helloworld::HelloRequest.new(name: user)).message + p "Greeting: #{message}" +end + +main diff --git a/examples/ruby/greeter_server.rb b/examples/ruby/greeter_server.rb new file mode 100755 index 0000000000..d4f9cf7d0f --- /dev/null +++ b/examples/ruby/greeter_server.rb @@ -0,0 +1,60 @@ +#!/usr/bin/env ruby + +# Copyright 2015, Google Inc. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +# Sample gRPC server that implements the Greeter::Helloworld service. +# +# Usage: $ path/to/greeter_server.rb + +this_dir = File.expand_path(File.dirname(__FILE__)) +lib_dir = File.join(this_dir, 'lib') +$LOAD_PATH.unshift(lib_dir) unless $LOAD_PATH.include?(lib_dir) + +require 'grpc' +require 'helloworld_services' + +# GreeterServer is simple server that implements the Helloworld Greeter server. +class GreeterServer < Helloworld::Greeter::Service + # say_hello implements the SayHello rpc method. + def say_hello(hello_req, _unused_call) + Helloworld::HelloReply.new(message: "Hello #{hello_req.name}") + end +end + +# main starts an RpcServer that receives requests to GreeterServer at the sample +# server port. +def main + s = GRPC::RpcServer.new + s.add_http2_port('0.0.0.0:50051') + s.handle(GreeterServer) + s.run +end + +main diff --git a/examples/ruby/grpc-demo.gemspec b/examples/ruby/grpc-demo.gemspec new file mode 100644 index 0000000000..2cc1eb8f41 --- /dev/null +++ b/examples/ruby/grpc-demo.gemspec @@ -0,0 +1,23 @@ +# -*- ruby -*- +# encoding: utf-8 + +Gem::Specification.new do |s| + s.name = 'grpc-demo' + s.version = '0.5.0' + s.authors = ['gRPC Authors'] + s.email = 'temiola@google.com' + s.homepage = 'https://github.com/grpc/grpc' + s.summary = 'gRPC Ruby overview sample' + s.description = 'Simple demo of using gRPC from Ruby' + + s.files = `git ls-files -- ruby/*`.split("\n") + s.executables = `git ls-files -- ruby/greeter*.rb ruby/route_guide/*.rb`.split("\n").map do |f| + File.basename(f) + end + s.require_paths = ['lib'] + s.platform = Gem::Platform::RUBY + + s.add_dependency 'grpc', '~> 0.6' + + s.add_development_dependency 'bundler', '~> 1.7' +end diff --git a/examples/ruby/lib/helloworld.rb b/examples/ruby/lib/helloworld.rb new file mode 100644 index 0000000000..82bdd78e2a --- /dev/null +++ b/examples/ruby/lib/helloworld.rb @@ -0,0 +1,18 @@ +# Generated by the protocol buffer compiler. DO NOT EDIT! +# source: helloworld.proto + +require 'google/protobuf' + +Google::Protobuf::DescriptorPool.generated_pool.build do + add_message "helloworld.HelloRequest" do + optional :name, :string, 1 + end + add_message "helloworld.HelloReply" do + optional :message, :string, 1 + end +end + +module Helloworld + HelloRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("helloworld.HelloRequest").msgclass + HelloReply = Google::Protobuf::DescriptorPool.generated_pool.lookup("helloworld.HelloReply").msgclass +end diff --git a/examples/ruby/lib/helloworld_services.rb b/examples/ruby/lib/helloworld_services.rb new file mode 100644 index 0000000000..7da45ebc6b --- /dev/null +++ b/examples/ruby/lib/helloworld_services.rb @@ -0,0 +1,24 @@ +# Generated by the protocol buffer compiler. DO NOT EDIT! +# Source: helloworld.proto for package 'helloworld' + +require 'grpc' +require 'helloworld' + +module Helloworld + module Greeter + + # TODO: add proto service documentation here + class Service + + include GRPC::GenericService + + self.marshal_class_method = :encode + self.unmarshal_class_method = :decode + self.service_name = 'helloworld.Greeter' + + rpc :SayHello, HelloRequest, HelloReply + end + + Stub = Service.rpc_stub_class + end +end diff --git a/examples/ruby/lib/route_guide.rb b/examples/ruby/lib/route_guide.rb new file mode 100644 index 0000000000..98bac8395c --- /dev/null +++ b/examples/ruby/lib/route_guide.rb @@ -0,0 +1,37 @@ +# Generated by the protocol buffer compiler. DO NOT EDIT! +# source: route_guide.proto + +require 'google/protobuf' + +Google::Protobuf::DescriptorPool.generated_pool.build do + add_message "examples.Point" do + optional :latitude, :int32, 1 + optional :longitude, :int32, 2 + end + add_message "examples.Rectangle" do + optional :lo, :message, 1, "examples.Point" + optional :hi, :message, 2, "examples.Point" + end + add_message "examples.Feature" do + optional :name, :string, 1 + optional :location, :message, 2, "examples.Point" + end + add_message "examples.RouteNote" do + optional :location, :message, 1, "examples.Point" + optional :message, :string, 2 + end + add_message "examples.RouteSummary" do + optional :point_count, :int32, 1 + optional :feature_count, :int32, 2 + optional :distance, :int32, 3 + optional :elapsed_time, :int32, 4 + end +end + +module Examples + Point = Google::Protobuf::DescriptorPool.generated_pool.lookup("examples.Point").msgclass + Rectangle = Google::Protobuf::DescriptorPool.generated_pool.lookup("examples.Rectangle").msgclass + Feature = Google::Protobuf::DescriptorPool.generated_pool.lookup("examples.Feature").msgclass + RouteNote = Google::Protobuf::DescriptorPool.generated_pool.lookup("examples.RouteNote").msgclass + RouteSummary = Google::Protobuf::DescriptorPool.generated_pool.lookup("examples.RouteSummary").msgclass +end diff --git a/examples/ruby/lib/route_guide_services.rb b/examples/ruby/lib/route_guide_services.rb new file mode 100644 index 0000000000..6e07653c42 --- /dev/null +++ b/examples/ruby/lib/route_guide_services.rb @@ -0,0 +1,27 @@ +# Generated by the protocol buffer compiler. DO NOT EDIT! +# Source: route_guide.proto for package 'examples' + +require 'grpc' +require 'route_guide' + +module Examples + module RouteGuide + + # TODO: add proto service documentation here + class Service + + include GRPC::GenericService + + self.marshal_class_method = :encode + self.unmarshal_class_method = :decode + self.service_name = 'examples.RouteGuide' + + rpc :GetFeature, Point, Feature + rpc :ListFeatures, Rectangle, stream(Feature) + rpc :RecordRoute, stream(Point), RouteSummary + rpc :RouteChat, stream(RouteNote), stream(RouteNote) + end + + Stub = Service.rpc_stub_class + end +end diff --git a/examples/ruby/route_guide/README.md b/examples/ruby/route_guide/README.md new file mode 100644 index 0000000000..c7231fb43f --- /dev/null +++ b/examples/ruby/route_guide/README.md @@ -0,0 +1,285 @@ +#gRPC Basics: Ruby + +This tutorial provides a basic Ruby programmer's introduction to working with gRPC. By walking through this example you'll learn how to: + +- Define a service in a .proto file. +- Generate server and client code using the protocol buffer compiler. +- Use the Ruby gRPC API to write a simple client and server for your service. + +It assumes that you have read the [Getting started](https://github.com/grpc/grpc/tree/master/examples) guide and are familiar with [protocol buffers] (https://developers.google.com/protocol-buffers/docs/overview). Note that the example in this tutorial uses the proto3 version of the protocol buffers language, which is currently in alpha release:you can find out more in the [proto3 language guide](https://developers.google.com/protocol-buffers/docs/proto3) and see the [release notes](https://github.com/google/protobuf/releases) for the new version in the protocol buffers Github repository. + +This isn't a comprehensive guide to using gRPC in Ruby: more reference documentation is coming soon. + +## Why use gRPC? + +Our example is a simple route mapping application that lets clients get information about features on their route, create a summary of their route, and exchange route information such as traffic updates with the server and other clients. + +With gRPC we can define our service once in a .proto file and implement clients and servers in any of gRPC's supported languages, which in turn can be run in environments ranging from servers inside Google to your own tablet - all the complexity of communication between different languages and environments is handled for you by gRPC. We also get all the advantages of working with protocol buffers, including efficient serialization, a simple IDL, and easy interface updating. + +## Example code and setup + +The example code for our tutorial is in [examples/ruby/route_guide](examples/ruby/route_guide). To download the example, clone this repository by running the following command: +```shell +$ git clone https://github.com/grpc/grpc.git +``` + +Then change your current directory to `examples/ruby/route_guide`: +```shell +$ cd examples/ruby/route_guide +``` + +You also should have the relevant tools installed to generate the server and client interface code - if you don't already, follow the setup instructions in [the Ruby quick start guide](examples/ruby). + + +## Defining the service + +Our first step (as you'll know from [Getting started](https://github.com/grpc/grpc/tree/master/examples)) is to define the gRPC *service* and the method *request* and *response* types using [protocol buffers] (https://developers.google.com/protocol-buffers/docs/overview). You can see the complete .proto file in [`examples/protos/route_guide.proto`](examples/protos/route_guide.proto). + +To define a service, you specify a named `service` in your .proto file: + +```protobuf +service RouteGuide { + ... +} +``` + +Then you define `rpc` methods inside your service definition, specifying their request and response types. gRPC lets you define four kinds of service method, all of which are used in the `RouteGuide` service: + +- A *simple RPC* where the client sends a request to the server using the stub and waits for a response to come back, just like a normal function call. +```protobuf + // Obtains the feature at a given position. + rpc GetFeature(Point) returns (Feature) {} +``` + +- A *server-side streaming RPC* where the client sends a request to the server and gets a stream to read a sequence of messages back. The client reads from the returned stream until there are no more messages. As you can see in our example, you specify a server-side streaming method by placing the `stream` keyword before the *response* type. +```protobuf + // Obtains the Features available within the given Rectangle. Results are + // streamed rather than returned at once (e.g. in a response message with a + // repeated field), as the rectangle may cover a large area and contain a + // huge number of features. + rpc ListFeatures(Rectangle) returns (stream Feature) {} +``` + +- A *client-side streaming RPC* where the client writes a sequence of messages and sends them to the server, again using a provided stream. Once the client has finished writing the messages, it waits for the server to read them all and return its response. You specify a server-side streaming method by placing the `stream` keyword before the *request* type. +```protobuf + // Accepts a stream of Points on a route being traversed, returning a + // RouteSummary when traversal is completed. + rpc RecordRoute(stream Point) returns (RouteSummary) {} +``` + +- A *bidirectional streaming RPC* where both sides send a sequence of messages using a read-write stream. The two streams operate independently, so clients and servers can read and write in whatever order they like: for example, the server could wait to receive all the client messages before writing its responses, or it could alternately read a message then write a message, or some other combination of reads and writes. The order of messages in each stream is preserved. You specify this type of method by placing the `stream` keyword before both the request and the response. +```protobuf + // Accepts a stream of RouteNotes sent while a route is being traversed, + // while receiving other RouteNotes (e.g. from other users). + rpc RouteChat(stream RouteNote) returns (stream RouteNote) {} +``` + +Our .proto file also contains protocol buffer message type definitions for all the request and response types used in our service methods - for example, here's the `Point` message type: +```protobuf +// Points are represented as latitude-longitude pairs in the E7 representation +// (degrees multiplied by 10**7 and rounded to the nearest integer). +// Latitudes should be in the range +/- 90 degrees and longitude should be in +// the range +/- 180 degrees (inclusive). +message Point { + int32 latitude = 1; + int32 longitude = 2; +} +``` + + +## Generating client and server code + +Next we need to generate the gRPC client and server interfaces from our .proto service definition. We do this using the protocol buffer compiler `protoc` with a special gRPC Ruby plugin. + +If you want to run this yourself, make sure you've installed protoc and followed the gRPC Ruby plugin [installation instructions](https://github.com/grpc/grpc/blob/master/INSTALL) first): + +Once that's done, the following command can be used to generate the ruby code. + +```shell +$ protoc -I ../../protos --ruby_out=lib --grpc_out=lib --plugin=protoc-gen-grpc=`which grpc_ruby_plugin` ../../protos/route_guide.proto +``` + +Running this command regenerates the following files in the lib directory: +- `lib/route_guide.pb` defines a module `Examples::RouteGuide` + - This contain all the protocol buffer code to populate, serialize, and retrieve our request and response message types +- `lib/route_guide_services.pb`, extends `Examples::RouteGuide` with stub and service classes + - a class `Service` for use as a base class when defining RouteGuide service implementations + - a class `Stub` that can be used to access remote RouteGuide instances + + +<a name="server"></a> +## Creating the server + +First let's look at how we create a `RouteGuide` server. If you're only interested in creating gRPC clients, you can skip this section and go straight to [Creating the client](#client) (though you might find it interesting anyway!). + +There are two parts to making our `RouteGuide` service do its job: +- Implementing the service interface generated from our service definition: doing the actual "work" of our service. +- Running a gRPC server to listen for requests from clients and return the service responses. + +You can find our example `RouteGuide` server in [examples/ruby/route_guide/route_guide_server.rb](examples/ruby/route_guide/route_guide_server.rb). Let's take a closer look at how it works. + +### Implementing RouteGuide + +As you can see, our server has a `ServerImpl` class that extends the generated `RouteGuide::Service`: + +```ruby +# ServerImpl provides an implementation of the RouteGuide service. +class ServerImpl < RouteGuide::Service +``` + +`ServerImpl` implements all our service methods. Let's look at the simplest type first, `GetFeature`, which just gets a `Point` from the client and returns the corresponding feature information from its database in a `Feature`. + +```ruby + def get_feature(point, _call) + name = @feature_db[{ + 'longitude' => point.longitude, + 'latitude' => point.latitude }] || '' + Feature.new(location: point, name: name) + end +``` + +The method is passed a _call for the RPC, the client's `Point` protocol buffer request, and returns a `Feature` protocol buffer. In the method we create the `Feature` with the appropriate information, and then `return` it. + +Now let's look at something a bit more complicated - a streaming RPC. `ListFeatures` is a server-side streaming RPC, so we need to send back multiple `Feature`s to our client. + +```ruby +# in ServerImpl + + def list_features(rectangle, _call) + RectangleEnum.new(@feature_db, rectangle).each + end +``` + +As you can see, here the request object is a `Rectangle` in which our client wants to find `Feature`s, but instead of returning a simple response we need to return an [Enumerator](http://ruby-doc.org//core-2.2.0/Enumerator.html) that yields the responses. In the method, we use a helper class `RectangleEnum`, to act as an Enumerator implementation. + +Similarly, the client-side streaming method `record_route` uses an [Enumerable](http://ruby-doc.org//core-2.2.0/Enumerable.html), but here it's obtained from the call object, which we've ignored in the earlier examples. `call.each_remote_read` yields each message sent by the client in turn. + +```ruby + call.each_remote_read do |point| + ... + end +``` +Finally, let's look at our bidirectional streaming RPC `route_chat`. + +```ruby + def route_chat(notes) + q = EnumeratorQueue.new(self) + t = Thread.new do + begin + notes.each do |n| + ... + end + end + q = EnumeratorQueue.new(self) + ... + return q.each_item + end +``` + +Here the method receives an [Enumerable](http://ruby-doc.org//core-2.2.0/Enumerable.html), but also returns an [Enumerator](http://ruby-doc.org//core-2.2.0/Enumerator.html) that yields the responses. The implementation demonstrates how to set these up so that the requests and responses can be handled concurrently. Although each side will always get the other's messages in the order they were written, both the client and server can read and write in any order — the streams operate completely independently. + +### Starting the server + +Once we've implemented all our methods, we also need to start up a gRPC server so that clients can actually use our service. The following snippet shows how we do this for our `RouteGuide` service: + +```ruby + s = GRPC::RpcServer.new + s.add_http2_port(port) + logger.info("... running insecurely on #{port}") + s.handle(ServerImpl.new(feature_db)) + s.run +``` +As you can see, we build and start our server using a `GRPC::RpcServer`. To do this, we: + +1. Create an instance of our service implementation class `ServerImpl`. +2. Specify the address and port we want to use to listen for client requests using the builder's `add_http2_port` method. +3. Register our service implementation with the `GRPC::RpcServer`. +4. Call `run` on the`GRPC::RpcServer` to create and start an RPC server for our service. + +<a name="client"></a> +## Creating the client + +In this section, we'll look at creating a Ruby client for our `RouteGuide` service. You can see our complete example client code in [examples/ruby/route_guide/route_guide_client.rb](examples/ruby/route_guide/route_guide_client.rb). + +### Creating a stub + +To call service methods, we first need to create a *stub*. + +We use the `Stub` class of the `RouteGuide` module generated from our .proto. + +```ruby + stub = RouteGuide::Stub.new('localhost:50051') +``` + +### Calling service methods + +Now let's look at how we call our service methods. Note that the gRPC Ruby only provides *blocking/synchronous* versions of each method: this means that the RPC call waits for the server to respond, and will either return a response or raise an exception. + +#### Simple RPC + +Calling the simple RPC `GetFeature` is nearly as straightforward as calling a local method. + +```ruby +GET_FEATURE_POINTS = [ + Point.new(latitude: 409_146_138, longitude: -746_188_906), + Point.new(latitude: 0, longitude: 0) +] +.. + GET_FEATURE_POINTS.each do |pt| + resp = stub.get_feature(pt) + ... + p "- found '#{resp.name}' at #{pt.inspect}" + end +``` + +As you can see, we create and populate a request protocol buffer object (in our case `Point`), and create a response protocol buffer object for the server to fill in. Finally, we call the method on the stub, passing it the context, request, and response. If the method returns `OK`, then we can read the response information from the server from our response object. + + +#### Streaming RPCs + +Now let's look at our streaming methods. If you've already read [Creating the server](#server) some of this may look very familiar - streaming RPCs are implemented in a similar way on both sides. Here's where we call the server-side streaming method `list_features`, which returns an `Enumerable` of `Features` + +```ruby + resps = stub.list_features(LIST_FEATURES_RECT) + resps.each do |r| + p "- found '#{r.name}' at #{r.location.inspect}" + end +``` + +The client-side streaming method `record_route` is similar, except there we pass the server an `Enumerable`. + +```ruby + ... + reqs = RandomRoute.new(features, points_on_route) + resp = stub.record_route(reqs.each, deadline) + ... +``` + +Finally, let's look at our bidirectional streaming RPC `route_chat`. In this case, we pass `Enumerable` to the method and get back an `Enumerable`. + +```ruby + resps = stub.route_chat(ROUTE_CHAT_NOTES) + resps.each { |r| p "received #{r.inspect}" } +``` + +Although it's not shown well by this example, each enumerable is independent of the other - both the client and server can read and write in any order — the streams operate completely independently. + +## Try it out! + +Build client and server: + +```shell +$ # from examples/ruby +$ gem install bundler && bundle install +``` +Run the server, which will listen on port 50051: +```shell +$ # from examples/ruby +$ bundle exec route_guide/route_guide_server.rb ../node/route_guide/route_guide_db.json & +``` +Run the client (in a different terminal): +```shell +$ # from examples/ruby +$ bundle exec route_guide/route_guide_client.rb ../node/route_guide/route_guide_db.json & +``` + diff --git a/examples/ruby/route_guide/route_guide_client.rb b/examples/ruby/route_guide/route_guide_client.rb new file mode 100755 index 0000000000..181623a68a --- /dev/null +++ b/examples/ruby/route_guide/route_guide_client.rb @@ -0,0 +1,165 @@ +#!/usr/bin/env ruby + +# Copyright 2015, Google Inc. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +# Sample app that connects to a Route Guide service. +# +# Usage: $ path/to/route_guide_client.rb path/to/route_guide_db.json & + +this_dir = File.expand_path(File.dirname(__FILE__)) +lib_dir = File.join(File.dirname(this_dir), 'lib') +$LOAD_PATH.unshift(lib_dir) unless $LOAD_PATH.include?(lib_dir) + +require 'grpc' +require 'route_guide_services' + +include Examples + +GET_FEATURE_POINTS = [ + Point.new(latitude: 409_146_138, longitude: -746_188_906), + Point.new(latitude: 0, longitude: 0) +] + +# runs a GetFeature rpc. +# +# - once with a point known to be present in the sample route database +# - once with a point that is not in the sample database +def run_get_feature(stub) + p 'GetFeature' + p '----------' + GET_FEATURE_POINTS.each do |pt| + resp = stub.get_feature(pt) + if resp.name != '' + p "- found '#{resp.name}' at #{pt.inspect}" + else + p "- found nothing at #{pt.inspect}" + end + end +end + +LIST_FEATURES_RECT = Rectangle.new( + lo: Point.new(latitude: 400_000_000, longitude: -750_000_000), + hi: Point.new(latitude: 420_000_000, longitude: -730_000_000)) + +# runs a ListFeatures rpc. +# +# - the rectangle to chosen to include most of the known features +# in the sample db. +def run_list_features(stub) + p 'ListFeatures' + p '------------' + resps = stub.list_features(LIST_FEATURES_RECT) + resps.each do |r| + p "- found '#{r.name}' at #{r.location.inspect}" + end +end + +# RandomRoute provides an Enumerable that yields a random 'route' of points +# from a list of Features. +class RandomRoute + def initialize(features, size) + @features = features + @size = size + end + + # yields a point, waiting between 0 and 1 seconds between each yield + # + # @return an Enumerable that yields a random point + def each + return enum_for(:each) unless block_given? + @size.times do + json_feature = @features[rand(0..@features.length)] + next if json_feature.nil? + location = json_feature['location'] + pt = Point.new( + Hash[location.each_pair.map { |k, v| [k.to_sym, v] }]) + p "- next point is #{pt.inspect}" + yield pt + sleep(rand(0..1)) + end + end +end + +# runs a RecordRoute rpc. +# +# - the rectangle to chosen to include most of the known features +# in the sample db. +def run_record_route(stub, features) + p 'RecordRoute' + p '-----------' + points_on_route = 10 # arbitrary + deadline = points_on_route # as delay b/w each is max 1 second + reqs = RandomRoute.new(features, points_on_route) + resp = stub.record_route(reqs.each, deadline) + p "summary: #{resp.inspect}" +end + +ROUTE_CHAT_NOTES = [ + RouteNote.new(message: 'doh - a deer', + location: Point.new(latitude: 0, longitude: 0)), + RouteNote.new(message: 'ray - a drop of golden sun', + location: Point.new(latitude: 0, longitude: 1)), + RouteNote.new(message: 'me - the name I call myself', + location: Point.new(latitude: 1, longitude: 0)), + RouteNote.new(message: 'fa - a longer way to run', + location: Point.new(latitude: 1, longitude: 1)), + RouteNote.new(message: 'soh - with needle and a thread', + location: Point.new(latitude: 0, longitude: 1)) +] + +# runs a RouteChat rpc. +# +# sends a canned set of route notes and prints out the responses. +def run_route_chat(stub) + p 'Route Chat' + p '----------' + # TODO: decouple sending and receiving, i.e have the response enumerator run + # on its own thread. + resps = stub.route_chat(ROUTE_CHAT_NOTES) + resps.each { |r| p "received #{r.inspect}" } +end + +def main + stub = RouteGuide::Stub.new('localhost:50051') + run_get_feature(stub) + run_list_features(stub) + run_route_chat(stub) + if ARGV.length == 0 + p 'no feature database; skipping record_route' + exit + end + raw_data = [] + File.open(ARGV[0]) do |f| + raw_data = MultiJson.load(f.read) + end + run_record_route(stub, raw_data) +end + +main diff --git a/examples/ruby/route_guide/route_guide_server.rb b/examples/ruby/route_guide/route_guide_server.rb new file mode 100755 index 0000000000..2b2b8084ef --- /dev/null +++ b/examples/ruby/route_guide/route_guide_server.rb @@ -0,0 +1,211 @@ +#!/usr/bin/env ruby +# -*- coding: utf-8 -*- + +# Copyright 2015, Google Inc. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +# Sample app that connects to a Route Guide service. +# +# Usage: $ path/to/route_guide_server.rb path/to/route_guide_db.json & + +this_dir = File.expand_path(File.dirname(__FILE__)) +lib_dir = File.join(File.dirname(this_dir), 'lib') +$LOAD_PATH.unshift(lib_dir) unless $LOAD_PATH.include?(lib_dir) + +require 'grpc' +require 'multi_json' +require 'route_guide_services' + +include Examples +COORD_FACTOR = 1e7 +RADIUS = 637_100 + +# Determines the distance between two points. +def calculate_distance(point_a, point_b) + to_radians = proc { |x| x * Math::PI / 180 } + lat_a = point_a.latitude / COORD_FACTOR + lat_b = point_b.latitude / COORD_FACTOR + long_a = point_a.longitude / COORD_FACTOR + long_b = point_b.longitude / COORD_FACTOR + φ1 = to_radians.call(lat_a) + φ2 = to_radians.call(lat_b) + Δφ = to_radians.call(lat_a - lat_b) + Δλ = to_radians.call(long_a - long_b) + a = Math.sin(Δφ / 2)**2 + + Math.cos(φ1) * Math.cos(φ2) + + Math.sin(Δλ / 2)**2 + (2 * RADIUS * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a))).to_i +end + +# RectangleEnum provides an Enumerator of the points in a feature_db within a +# given Rectangle. +class RectangleEnum + # @param [Hash] feature_db + # @param [Rectangle] bounds + def initialize(feature_db, bounds) + @feature_db = feature_db + @bounds = bounds + lats = [@bounds.lo.latitude, @bounds.hi.latitude] + longs = [@bounds.lo.longitude, @bounds.hi.longitude] + @lo_lat, @hi_lat = lats.min, lats.max + @lo_long, @hi_long = longs.min, longs.max + end + + # in? determines if location lies within the bounds of this instances + # Rectangle. + def in?(location) + location['longitude'] >= @lo_long && + location['longitude'] <= @hi_long && + location['latitude'] >= @lo_lat && + location['latitude'] <= @hi_lat + end + + # each yields the features in the instances feature_db that lie within the + # instance rectangle. + def each + return enum_for(:each) unless block_given? + @feature_db.each_pair do |location, name| + next unless in?(location) + next if name.nil? || name == '' + pt = Point.new( + Hash[location.each_pair.map { |k, v| [k.to_sym, v] }]) + yield Feature.new(location: pt, name: name) + end + end +end + +# A EnumeratorQueue wraps a Queue to yield the items added to it. +class EnumeratorQueue + extend Forwardable + def_delegators :@q, :push + + def initialize(sentinel) + @q = Queue.new + @sentinel = sentinel + @received_notes = {} + end + + def each_item + return enum_for(:each_item) unless block_given? + loop do + r = @q.pop + break if r.equal?(@sentinel) + fail r if r.is_a? Exception + yield r + end + end +end + +# ServerImpl provides an implementation of the RouteGuide service. +class ServerImpl < RouteGuide::Service + # @param [Hash] feature_db {location => name} + def initialize(feature_db) + @feature_db = feature_db + @received_notes = Hash.new { |h, k| h[k] = [] } + end + + def get_feature(point, _call) + name = @feature_db[{ + 'longitude' => point.longitude, + 'latitude' => point.latitude }] || '' + Feature.new(location: point, name: name) + end + + def list_features(rectangle, _call) + RectangleEnum.new(@feature_db, rectangle).each + end + + def record_route(call) + started, elapsed_time = 0, 0 + distance, count, features, last = 0, 0, 0, nil + call.each_remote_read do |point| + count += 1 + name = @feature_db[{ + 'longitude' => point.longitude, + 'latitude' => point.latitude }] || '' + features += 1 unless name == '' + if last.nil? + last = point + started = Time.now.to_i + next + end + elapsed_time = Time.now.to_i - started + distance += calculate_distance(point, last) + last = point + end + RouteSummary.new(point_count: count, + feature_count: features, + distance: distance, + elapsed_time: elapsed_time) + end + + def route_chat(notes) + q = EnumeratorQueue.new(self) + # run a separate thread that processes the incoming requests + t = Thread.new do + begin + notes.each do |n| + key = { + 'latitude' => n.location.latitude, + 'longitude' => n.location.longitude + } + earlier_msgs = @received_notes[key] + @received_notes[key] << n.message + # send back the earlier messages at this point + earlier_msgs.each do |r| + q.push(RouteNote.new(location: n.location, message: r)) + end + end + q.push(self) # signal completion + rescue StandardError => e + q.push(e) # signal completion via an error + end + end + q.each_item + end +end + +def main + if ARGV.length == 0 + fail 'Please specify the path to the route_guide json database' + end + raw_data = [] + File.open(ARGV[0]) do |f| + raw_data = MultiJson.load(f.read) + end + feature_db = Hash[raw_data.map { |x| [x['location'], x['name']] }] + port = '0.0.0.0:50051' + s = GRPC::RpcServer.new + s.add_http2_port(port) + GRPC.logger.info("... running insecurely on #{port}") + s.handle(ServerImpl.new(feature_db)) + s.run +end + +main |