API Gateway:Desenvolver plugins de gateway em Go

Instale o Go 1.24 ou superior seguindo o guia de instalação oficial.

• Baixe o arquivo de instalação.

• Execute o instalador. Por padrão, o Go é instalado em Program Files ou Program Files (x86).

• Pressione Win+R, insira cmd e clique em OK para abrir o prompt de comando. Execute go version para verificar a instalação.

• Baixe o pacote de instalação.

• Clique duas vezes no pacote para instalar. O Go é instalado em /usr/local/go por padrão.

• Abra um terminal e execute go version para verificar a instalação.

• Baixe o pacote de instalação.

• Execute os comandos a seguir para instalar o Go:

  • Instale o Go.

    rm -rf /usr/local/go && tar -C /usr/local -xzf go1.24.4.linux-amd64.tar.gz

  • Configure a variável de ambiente.

    export PATH=$PATH:/usr/local/go/bin

  • Execute go version para verificar a instalação.

package main

import (
  "github.com/higress-group/wasm-go/pkg/wrapper"
  logs "github.com/higress-group/wasm-go/pkg/log"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
  "github.com/tidwall/gjson"
)

func main() {}

func init() {
  wrapper.SetCtx(
    // Plugin name
    "my-plugin",
    // Custom configuration parser
     wrapper.ParseConfigBy(parseConfig),
    // Hook into the request header processing phase
    wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
  )
}

// Custom plugin configuration
type MyConfig struct {
  mockEnable bool
}

// Parse the JSON configuration into the config struct.
// The gateway console converts YAML to JSON automatically.
func parseConfig(json gjson.Result, config *MyConfig, log logs.Log) error {
  config.mockEnable = json.Get("mockEnable").Bool()
  return nil
}

func onHttpRequestHeaders(ctx wrapper.HttpContext, config MyConfig, log logs.Log) types.Action {
  proxywasm.AddHttpRequestHeader("hello", "world")
  if config.mockEnable {
    proxywasm.SendHttpResponse(200, nil, []byte("hello world"), -1)
  }
  return types.HeaderContinue
}

version: '3.7'
services:
  envoy:
    image: higress-registry.cn-hangzhou.cr.aliyuncs.com/higress/gateway:v2.1.5
    entrypoint: /usr/local/bin/envoy
    # Enable debug-level logging for Wasm. Use info level in production.
    command: -c /etc/envoy/envoy.yaml --component-log-level wasm:debug
    depends_on:
    - httpbin
    networks:
    - wasmtest
    ports:
    - "10000:10000"
    volumes:
    - ./envoy.yaml:/etc/envoy/envoy.yaml
    - ./main.wasm:/etc/envoy/main.wasm

  httpbin:
    image: kennethreitz/httpbin:latest
    networks:
    - wasmtest
    ports:
    - "12345:80"

networks:
  wasmtest: {}

admin:
  address:
    socket_address:
      protocol: TCP
      address: 0.0.0.0
      port_value: 9901
static_resources:
  listeners:
  - name: listener_0
    address:
      socket_address:
        protocol: TCP
        address: 0.0.0.0
        port_value: 10000
    filter_chains:
    - filters:
      - name: envoy.filters.network.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
          scheme_header_transformation:
            scheme_to_overwrite: https
          stat_prefix: ingress_http
          route_config:
            name: local_route
            virtual_hosts:
            - name: local_service
              domains: ["*"]
              routes:
              - match:
                  prefix: "/"
                route:
                  cluster: httpbin
          http_filters:
          - name: wasmdemo
            typed_config:
              "@type": type.googleapis.com/udpa.type.v1.TypedStruct
              type_url: type.googleapis.com/envoy.extensions.filters.http.wasm.v3.Wasm
              value:
                config:
                  name: wasmdemo
                  vm_config:
                    runtime: envoy.wasm.runtime.v8
                    code:
                      local:
                        filename: /etc/envoy/main.wasm
                  configuration:
                    "@type": "type.googleapis.com/google.protobuf.StringValue"
                    value: |
                      {
                        "mockEnable": false
                      }
          - name: envoy.filters.http.router
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router
  clusters:
  - name: httpbin
    connect_timeout: 30s
    type: LOGICAL_DNS
    # Comment out the following line to test on v6 networks
    dns_lookup_family: V4_ONLY
    lb_policy: ROUND_ROBIN
    load_assignment:
      cluster_name: httpbin
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: httpbin
                port_value: 80

docker compose up

curl http://127.0.0.1:10000/get

{
  "args": {},
  "headers": {
    "Accept": "*/*",
    "Hello": "world",
    "Host": "127.0.0.1:10000",
    "Original-Host": "127.0.0.1:10000",
    "Req-Start-Time": "1681269273896",
    "User-Agent": "curl/7.79.1",
    "X-Envoy-Expected-Rq-Timeout-Ms": "15000"
  },
  "origin": "172.18.0.3",
  "url": "https://127.0.0.1:10000/get"
}

curl http://127.0.0.1:12345/get

configuration:
    "@type": "type.googleapis.com/google.protobuf.StringValue"
    value: |
      {
        "mockEnable": true
      }

curl http://127.0.0.1:10000/get

hello world

package main

import (
  "github.com/higress-group/wasm-go/pkg/wrapper"
  logs "github.com/higress-group/wasm-go/pkg/log"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
)

func main() {}

func init() {
  wrapper.SetCtx(
    "hello-world",
    wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
  )
}

type MyConfig struct {}

func onHttpRequestHeaders(ctx wrapper.HttpContext, config MyConfig, log logs.Log) types.Action {
  proxywasm.SendHttpResponse(200, nil, []byte("hello world"), -1)
  return types.HeaderContinue
}

package main

import (
  "errors"
  "net/http"
  "strings"
  "github.com/higress-group/wasm-go/pkg/wrapper"
  logs "github.com/higress-group/wasm-go/pkg/log"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
  "github.com/tidwall/gjson"
)

func main() {}

func init() {
  wrapper.SetCtx(
    "http-call",
    wrapper.ParseConfigBy(parseConfig),
    wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
  )
}

type MyConfig struct {
  // HTTP client for external calls
  client      wrapper.HttpClient
  // Path to request on the external service
  requestPath string
  // Response header key to extract and inject into the original request
  tokenHeader string
}

func parseConfig(json gjson.Result, config *MyConfig, log logs.Log) error {
  config.tokenHeader = json.Get("tokenHeader").String()
  if config.tokenHeader == "" {
    return errors.New("missing tokenHeader in config")
  }
  config.requestPath = json.Get("requestPath").String()
  if config.requestPath == "" {
    return errors.New("missing requestPath in config")
  }
  // Full FQDN with service type suffix.
  // Examples: my-svc.dns, my-svc.static,
  //   service-provider.DEFAULT-GROUP.public.nacos,
  //   httpbin.my-ns.svc.cluster.local
  serviceName := json.Get("serviceName").String()
  servicePort := json.Get("servicePort").Int()
  if servicePort == 0 {
    if strings.HasSuffix(serviceName, ".static") {
      // Default port for static IP services
      servicePort = 80
    }
  }
  config.client = wrapper.NewClusterClient(wrapper.FQDNCluster{
    FQDN: serviceName,
    Port: servicePort,
        })
}

func onHttpRequestHeaders(ctx wrapper.HttpContext, config MyConfig, log logs.Log) types.Action {
  // Send an async HTTP GET request. Default timeout is 500 ms.
  err := config.client.Get(config.requestPath, nil,
           // Callback runs when the response arrives
           func(statusCode int, responseHeaders http.Header, responseBody []byte) {
             if statusCode != http.StatusOK {
               log.Errorf("http call failed, status: %d", statusCode)
               proxywasm.SendHttpResponse(http.StatusInternalServerError, nil,
                 []byte("http call failed"), -1)
               return
             }
             log.Infof("get status: %d, response body: %s", statusCode, responseBody)
             // Extract the token from the response and add it to the original request
             token := responseHeaders.Get(config.tokenHeader)
             if token != "" {
               proxywasm.AddHttpRequestHeader(config.tokenHeader, token)
             }
             // Resume the paused request so it can be forwarded to the backend
             proxywasm.ResumeHttpRequest()
    })

  if err != nil {
    // If the service call fails, let the request proceed and log the error
    log.Errorf("Error occured while calling http, it seems cannot find the service cluster.")
    return types.ActionContinue
  } else {
    // Pause the request until the async callback completes
    return types.HeaderStopAllIterationAndWatermark
  }
}

package main

import (
  "strconv"
  "time"

  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
  "github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
  "github.com/tidwall/gjson"
  "github.com/tidwall/resp"

  "github.com/higress-group/wasm-go/pkg/wrapper"
  logs "github.com/higress-group/wasm-go/pkg/log"
)

func main() {}

func init() {
  wrapper.SetCtx(
    "redis-demo",
    wrapper.ParseConfigBy(parseConfig),
    wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
    wrapper.ProcessResponseHeadersBy(onHttpResponseHeaders),
  )
}

type RedisCallConfig struct {
  client wrapper.RedisClient
  qpm    int
}

func parseConfig(json gjson.Result, config *RedisCallConfig, log logs.Log) error {
  // Full FQDN with service type suffix.
  // Examples: my-redis.dns, redis.my-ns.svc.cluster.local
  serviceName := json.Get("serviceName").String()
  servicePort := json.Get("servicePort").Int()
  if servicePort == 0 {
    if strings.HasSuffix(serviceName, ".static") {
      servicePort = 80
    } else {
      servicePort = 6379
    }
  }
  username := json.Get("username").String()
  password := json.Get("password").String()
  // Timeout in milliseconds
  timeout := json.Get("timeout").Int()
  if timeout == 0 {
    timeout = 1000
  }
  qpm := json.Get("qpm").Int()
  config.qpm = int(qpm)
  config.client = wrapper.NewRedisClusterClient(wrapper.FQDNCluster{
    FQDN: serviceName,
    Port: servicePort,
  })
  return config.client.Init(username, password, timeout)
}

func onHttpRequestHeaders(ctx wrapper.HttpContext, config RedisCallConfig, log logs.Log) types.Action {
  now := time.Now()
  minuteAligned := now.Truncate(time.Minute)
  timeStamp := strconv.FormatInt(minuteAligned.Unix(), 10)
  // If err != nil, the gateway likely cannot reach the Redis backend.
  // Verify that the Redis service has not been deleted.
  err := config.client.Incr(timeStamp, func(response resp.Value) {
    if response.Error() != nil {
      log.Errorf("call redis error: %v", response.Error())
      proxywasm.ResumeHttpRequest()
    } else {
      ctx.SetContext("timeStamp", timeStamp)
      ctx.SetContext("callTimeLeft", strconv.Itoa(config.qpm-response.Integer()))
      if response.Integer() == 1 {
        err := config.client.Expire(timeStamp, 60, func(response resp.Value) {
          if response.Error() != nil {
            log.Errorf("call redis error: %v", response.Error())
          }
          proxywasm.ResumeHttpRequest()
        })
        if err != nil {
          log.Errorf("Error occured while calling redis, it seems cannot find the redis cluster.")
          proxywasm.ResumeHttpRequest()
        }
      } else {
        if response.Integer() > config.qpm {
          proxywasm.SendHttpResponse(429, [][2]string{{"timeStamp", timeStamp}, {"callTimeLeft", "0"}}, []byte("Too many requests\n"), -1)
        } else {
          proxywasm.ResumeHttpRequest()
        }
      }
    }
  })
  if err != nil {
    // If the Redis call fails, let the request proceed and log the error
    log.Errorf("Error occured while calling redis, it seems cannot find the redis cluster.")
    return types.HeaderContinue
  } else {
    // Pause the request until the Redis callback completes
    return types.HeaderStopAllIterationAndWatermark
  }
}

func onHttpResponseHeaders(ctx wrapper.HttpContext, config RedisCallConfig, log logs.Log) types.Action {
  if ctx.GetContext("timeStamp") != nil {
    proxywasm.AddHttpResponseHeader("timeStamp", ctx.GetContext("timeStamp").(string))
  }
  if ctx.GetContext("callTimeLeft") != nil {
    proxywasm.AddHttpResponseHeader("callTimeLeft", ctx.GetContext("callTimeLeft").(string))
  }
  return types.HeaderContinue
}