Envoy HTTP流量分割 流量镜像

流量分割：

        动态调整权重来分格流量。

routes
  - match: {...}
  route:
    weight_clusters: {...}
      clusters: [] # 与当前路由关联的一个或多个集群， 必选参数；
      - name: ... # 集群名称；
        weight: ... # 集群权重， 取值范围为0至total_weight；
        metadata_match: {...} # 子集负载均衡器使用的端点元数据匹配条件， 可选参数， 仅用于上游集群中具有与此字段中设置的元数据匹配的元数
        端点以进行流量分配；
      total_weight: ... # 总权重值， 默认为100；
      runtime_key_prefix: ... # 可选参数， 用于设定键前缀， 从而每个集群以“runtime_key_prefix+.+cluster[i].name”为其键名， 并能够以运行时
      键值的方式为每个集群提供权重； 其中， cluster[i].name表示列表中第i个集群名称

示例：

admin:
  access_log_path: "/dev/null"
  address:
    socket_address:
      address: 0.0.0.0
      port_value: 9901

static_resources:
  listeners:
  - address:
      socket_address:
        address: 0.0.0.0
        port_value: 80
    name: listener_http
    filter_chains:
    - filters:
      - name: envoy.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.config.filter.network.http_connection_manager.v2.HttpConnectionManager
          codec_type: auto
          stat_prefix: ingress_http
          route_config:
            name: local_route
            virtual_hosts:
            - name: vh_001
              domains: ["*"]
              routes:
              - match:
                  prefix: "/"
                route:
                  weighted_clusters:
                    clusters:
                    - name: myapp-v1.5
                      weight: 90
                    - name: myapp-v1.6
                      weight: 10
                    total_weight: 100
                    runtime_key_prefix: routing.traffic_split
          http_filters:
          - name: envoy.router

  clusters:
  - name: myapp-v1.5
    connect_timeout: 0.25s
    type: STRICT_DNS
    lb_policy: ROUND_ROBIN
    http2_protocol_options: {}
    load_assignment: 
      cluster_name: myapp-v1.5
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: myapp-v1.5
                port_value: 80

  - name: myapp-v1.6
    connect_timeout: 0.25s
    type: STRICT_DNS
    lb_policy: ROUND_ROBIN
    http2_protocol_options: {}
    load_assignment:
      cluster_name: myapp-v1.6
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: myapp-v1.6
                port_value: 80

动态修改权重：

curl -XPOST 'http://172.20.0.7:9901/runtime_modify?routing.traffic_split.myapp-v1.5=0&routing.traffic_split.myapp-v1.6=100'

流量镜像：

        将生产流量拷贝到测试集群或新版本集群上。

route:
  cluster|weighted_clusters:
  ...
  request_mirror_policy:
    cluster": "..."
    runtime_key": "..." # 快废弃的参数，使用runtime_fraction
    runtime_fraction": "{...}"
      default_value: # 运行时键值不可用时， 则使用此默认值；
        numerator: # 指定分子， 默认为0；
        denominator: # 指定分母， 小于分子时， 最终百分比为1； 分母可固定使用HUNDRED（ 默认） 、 TEN_THOUSAND和MILLION；
      runtime_key: routing.request_mirror.KEY # 指定要使用的运行时键， 其值需要用户自定义

示例：

admin:
  access_log_path: "/dev/null"
  address:
    socket_address:
      address: 0.0.0.0
      port_value: 9901

static_resources:
  listeners:
  - address:
      socket_address:
        address: 0.0.0.0
        port_value: 80
    name: listener_http
    filter_chains:
    - filters:
      - name: envoy.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.config.filter.network.http_connection_manager.v2.HttpConnectionManager
          codec_type: auto
          stat_prefix: ingress_http
          route_config:
            name: local_route
            virtual_hosts:
            - name: vh_001
              domains: ["*"]
              routes:
              - match:
                  prefix: "/"
                route:
                  cluster: myapp-v1.5
                  request_mirror_policy:
                    cluster: myapp-v1.6
                    runtime_fraction:
                      default_value:
                        numerator: 10
                        denominator: HUNDRED
                      runtime_key: routing.request_mirror.myapp
          http_filters:
          - name: envoy.router

  clusters:
  - name: myapp-v1.5
    connect_timeout: 0.25s
    type: STRICT_DNS
    lb_policy: ROUND_ROBIN
    http2_protocol_options: {}
    load_assignment:
      cluster_name: myapp-v1.5
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: myapp-v1.5
                port_value: 80

  - name: myapp-v1.6
    connect_timeout: 0.25s
    type: STRICT_DNS
    lb_policy: ROUND_ROBIN
    http2_protocol_options: {}
    load_assignment:
      cluster_name: myapp-v1.6
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: myapp-v1.6
                port_value: 80

修改流量比例：从前端来看依然是1.5在响应，从日志中就可以看到1.6的也在响应，说明一部分流量已近被拷贝到1.6中了。

curl -XPOST 'http://172.21.0.2:9901/runtime_modify?routing.request_mirror.myapp=50'