服务发现
Registry 接口分为两个，Registrar 为实例注册和反注册，Discovery 为服务实例列表获取
创建一个 Discoverer
服务间的通信使用的grpc，放到data层，实现的是从uses服务调用orders服务
app/users/internal/data.go 加入 NewDiscovery和 NewOrderServiceClient，需要把新加的2个方法加入到 ProviderSet
需要把新生成的orderClient注入到Data里面 orderClient orders.OrderClient
package data
import (
"context"
"github.com/go-kratos/kratos/contrib/registry/nacos/v2"
"github.com/go-kratos/kratos/v2/log"
"github.com/go-kratos/kratos/v2/middleware/recovery"
"github.com/go-kratos/kratos/v2/registry"
"github.com/go-kratos/kratos/v2/transport/grpc"
"github.com/google/wire"
"github.com/nacos-group/nacos-sdk-go/clients"
"github.com/nacos-group/nacos-sdk-go/common/constant"
"github.com/nacos-group/nacos-sdk-go/vo"
"gorm.io/driver/mysql"
"gorm.io/gorm"
"time"
"xgs_kratos/gen/config/users"
"xgs_kratos/gen/orders"
)
// ProviderSet is data providers.
var ProviderSet = wire.NewSet(NewData, NewDiscovery, CreateRegister, NewOrderServiceClient, NewUserRepo)
// Data .
type Data struct {
// TODO wrapped database client
db *gorm.DB
log *log.Helper
orderClient orders.OrderClient
}
// NewData .
func NewData(c *conf.Data, logger log.Logger, client orders.OrderClient) (*Data, func(), error) {
cleanup := func() {
log.NewHelper(logger).Info("closing the data resources")
}
db, err := gorm.Open(mysql.Open(c.Database.Source), &gorm.Config{})
if err != nil {
log.Fatalf("failed to connect database: %v", err)
panic(err)
}
return &Data{
db: db,
log: log.NewHelper(logger),
orderClient: client,
}, cleanup, nil
}
// NewDiscovery 服务发现
func NewDiscovery(conf *conf.Data) registry.Discovery {
sc := []constant.ServerConfig{
{
IpAddr: conf.Nacos.Addr,
Port: conf.Nacos.Port,
},
}
cc := constant.ClientConfig{
NamespaceId: conf.Nacos.NamespaceId,
TimeoutMs: 5000,
}
client, err := clients.NewNamingClient(
vo.NacosClientParam{
ClientConfig: &cc,
ServerConfigs: sc,
},
)
if err != nil {
panic(err)
}
r := nacos.New(client)
return r
}
// NewOrderServiceClient orders 服务客户端
func NewOrderServiceClient(r registry.Discovery) orders.OrderClient {
conn, err := grpc.DialInsecure(
context.Background(),
grpc.WithEndpoint("discovery:///orders-xgs.grpc"),
grpc.WithDiscovery(r),
grpc.WithTimeout(time.Second*2),
grpc.WithMiddleware(
recovery.Recovery(),
),
)
if err != nil {
panic(err)
}
c := orders.NewOrderClient(conn)
return c
}
在users下执行 wire
以ListUser方法为例子进行调用
app/users/internal/user.go
package data
import (
"context"
"fmt"
"github.com/go-kratos/kratos/v2/log"
"xgs_kratos/app/users/internal/biz"
"xgs_kratos/app/users/internal/data/dal"
"xgs_kratos/gen/orders"
"xgs_kratos/gen/users"
)
//data 层处理数据的存储和读取
type userRepo struct {
data *Data
log *log.Helper
}
// NewUserRepo . r registry.Discovery,
func NewUserRepo(data *Data, logger log.Logger) biz.UserRepo {
return &userRepo{
data: data,
log: log.NewHelper(logger),
}
}
// CreateUser 创建用户
func (r *userRepo) CreateUser(ctx context.Context, req *users.CreateUserRequest) (*users.CreateUserReply, error) {
user := dal.UserMo{
Age: req.Age,
Name: req.Name,
Email: req.Email,
}
result := r.data.db.Create(&user)
if result.Error != nil {
return nil, result.Error
}
return &users.CreateUserReply{
Id: user.Id,
}, nil
}
func (r *userRepo) ListUser(ctx context.Context, req *users.ListUserRequest) ([]*users.UserData, error) {
//获取order服务的client
client := r.data.orderClient
order, err := client.CreateOrder(ctx, &orders.CreateOrderRequest{
OrderNo: 1,
})
if err != nil {
return nil, err
}
fmt.Println(order)
var results []dal.UserMo
res := r.data.db.Find(&results)
if res.Error != nil {
return nil, res.Error
}
var userDatas []*users.UserData
for _, result := range results {
userDatas = append(userDatas, &users.UserData{
Id: result.Id,
Name: result.Name,
Age: result.Age,
Email: result.Email,
})
}
return userDatas, nil
}
从新生成一下代码 buf generate
如果服务是分开部署的，需要拿到对方的存根 proto 执行 kratos proto client xxx.proto生成client
分别启动users和orders 服务是都是注册成功的，由于注册的是http和grpc所有后面拼接的有http和grpc，调用的时候需要拼接上
postman请求看效果
看日志输出 users
再看orders服务的日志输出
