Micro API gateway Middleware

Look at us from above Api The gateway still has a lot to do ：

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Mciro Examples of plug-in forms provided

1: Create a new Gateway project structure

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Add a demonstration of the registration sequence of multiple plug-ins for a user

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2: Define a plug-in auth.go

package auth

import (

    "github.com/micro/cli/v2"

    "github.com/micro/micro/v2/plugin"

    "log"

    "net/http"

)

func NewPlugin() plugin.Plugin {

    return plugin.NewPlugin(

        //  The plugin name 

        plugin.WithName("example"),

        // Some parameter descriptions of the query command 

        plugin.WithFlag(&cli.StringFlag{

            Name:   "example_flag",

            Usage:  "This is an example plugin flag",

            EnvVars: []string{"EXAMPLE_FLAG"},

            Value: "avalue",

        }),

        //  Configure plug-in initialization ,cli.Context Project startup parameters are included in 

        plugin.WithInit(func(ctx *cli.Context) error {

            println(" I am a custom authentication middleware processor -----------------------")

            log.Println("Got value for example_flag", ctx.String("example_flag"))

            return nil

        }),

        //  Configure handler , Pay attention to and wrapper Different , His parameters are http Bag ResponseWriter and Request

        plugin.WithHandler(cAuthWrapper()),

    )

}

// Query what needs to be done 

func cAuthWrapper() plugin.Handler {

    return func(h http.Handler) http.Handler {

        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

            println(" Come in, come in, come to the authentication middleware ！")

            // This place is very important ---- The following step must be performed , Ensure the execution of other plug-ins and business code , Otherwise, no response body returns 

            h.ServeHTTP(w, r)

        })

    }

}

2: Define a plug-in auth2.go

package auth

import (

    "github.com/micro/cli/v2"

    "github.com/micro/micro/v2/plugin"

    "log"

    "net/http"

)

func NewPlugin2() plugin.Plugin {

    return plugin.NewPlugin(

        //  The plugin name 

        plugin.WithName("example"),

        // Some parameter descriptions of the query command 

        plugin.WithFlag(&cli.StringFlag{

            Name:   "example_flag",

            Usage:  "This is an example plugin flag",

            EnvVars: []string{"EXAMPLE_FLAG"},

            Value: "avalue",

        }),

        //  Configure plug-in initialization ,cli.Context Project startup parameters are included in 

        plugin.WithInit(func(ctx *cli.Context) error {

            println(" I am a custom authentication middleware processor 222222-----------------------")

            log.Println("Got value for example_flag", ctx.String("example_flag"))

            return nil

        }),

        //  Configure handler , Pay attention to and wrapper Different , His parameters are http Bag ResponseWriter and Request

        plugin.WithHandler(cAuthWrapper2()),

    )

}

// Query what needs to be done 

func cAuthWrapper2() plugin.Handler {

    return func(h http.Handler) http.Handler {

        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

            println(" Come in, come in, come to the authentication middleware 222222222！")

            // This place is very important ---- The following step must be performed , Ensure the execution of other plug-ins and business code , Otherwise, no response body returns 

            h.ServeHTTP(w, r)

        })

    }

}

3: Register plug-ins , In our main.go Register our plug-ins inside

package main

import (

    "github.com/micro/micro/v2/client/api"

    "github.com/micro/micro/v2/cmd"

    "github.com/micro/micro/v2/plugin"

    "micro/plugins/auth"

)

func main()  {

    // The first way 

    err := api.Register(auth.NewPlugin())

    if err != nil {

        //log.Fatal("auth register")

    }

    //  The second way ：

    err =plugin.Register(auth.NewPlugin2())

    if err != nil {

        //log.Fatal("auth register")

    }

    cmd.Init()

}

4: Start our gateway , The main relevant startup command parameters are （ The following parameters are indispensable ）：

PS: The following parameters are indispensable, or you will be prompted with relevant wrong commands

D:\code\go\micro-greeter\api-gateway>go run main.go

 I am a custom authentication middleware processor 222222-----------------------

2021-01-28 17:08:58.552198 I | Got value for example_flag avalue

No command provided to micro. Please refer to 'micro --help'

exit status 1

Start the gateway command correctly ：

go run main.go --registry=etcd --registry_address=192.168.219.130:2379 api --address=0.0.0.0:9000 --namespace=go.micro --type=service

Check our startup log ：

D:\code\go\micro-greeter\api-gateway>go run main.go --registry=etcd --registry_address=192.168.219.130:2379  api --address=0.0.0.0:9000 --namespace=go.micro --type=service

 I am a custom authentication middleware processor 222222-----------------------

2021-01-28 17:10:19.689117 I | Got value for example_flag avalue

 I am a custom authentication middleware processor -----------------------

2021-01-28 17:10:19.731005 I | Got value for example_flag avalue

2021-01-28 17:10:19  file=api/api.go:285 level=info service=api Registering API Default Handler at /

2021-01-28 17:10:19  file=http/http.go:90 level=info service=api HTTP API Listening on [::]:9000

2021-01-28 17:10:19  [email protected]/service.go:200 level=info service=api Starting [service] go.micro.api

2021-01-28 17:10:19  file=grpc/grpc.go:864 level=info service=api Server [grpc] Listening on [::]:62154

2021-01-28 17:10:19  file=grpc/grpc.go:697 level=info service=api Registry [etcd] Registering node: go.micro.api-b10fb08b-5834-4316-9690-2109eaca1899

Last registered , Install first ！

At this point we visit our API Interface ：http://localhost:9000/greeter/call

2021-01-28 17:10:19.731005 I | Got value for example_flag avalue

2021-01-28 17:10:19  file=api/api.go:285 level=info service=api Registering API Default Handler at /

2021-01-28 17:10:19  file=http/http.go:90 level=info service=api HTTP API Listening on [::]:9000

2021-01-28 17:10:19  [email protected]/service.go:200 level=info service=api Starting [service] go.micro.api

2021-01-28 17:10:19  file=grpc/grpc.go:864 level=info service=api Server [grpc] Listening on [::]:62154

2021-01-28 17:10:19  file=grpc/grpc.go:697 level=info service=api Registry [etcd] Registering node: go.micro.api-b10fb08b-5834-4316-9690-2109eaca1899

 Come in, come in, come to the authentication middleware ！

 Come in, come in, come to the authentication middleware 222222222！

::1 - - [28/Jan/2021:17:10:47 +0800] "GET /greeter/call HTTP/1.1" 200 16 "" "PostmanRuntime/7.26.8"