gRPC Basics tutorial実況中継

チュートリアルでわかること

Pcotobufのcomplireでserver/clientのコード生成

Goで単純なserver/clientのサービスを作ったときに、gRPC APIををつかったAPIを作成できる

前提知識

つくるアプリ

simple route mapping application

クライアントがルートの特徴情報を取得して、ルートの要約を作ってtrafific updateなどのルート情報をサーバーや他のクライアントと交換する

all the complexity of communication between different languages and environments is handled for you by gRPC.

サービス定義をする

gRPC serviceを定義する

code:route_guide.proto

// Interface exported by the server.

service RouteGuide {

// A simple RPC.

//

// Obtains the feature at a given position.

//

// A feature with an empty name is returned if there's no feature at the given

// position.

rpc GetFeature(Point) returns (Feature) {}

// A server-to-client streaming RPC.

//

// 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-to-server streaming RPC.

//

// 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.

//

// 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) {}

}

code:route_guide.proto

// 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;

}