创建从Docker容器上的进程到同一容器上另一个进程的连接时，连接被拒绝

问题描述

我正在使用localstack框架并在docker容器上运行我能够从主机连接到在容器（端口4569）上运行的发电机服务。尝试从在此容器上运行的lambda连接到dynamo（在同一容器上运行）时，连接被拒绝。我使用的IP是容器的名称。（例如，telnet localstack 4569将无法通过lambda运行）

Docker ps返回：

13:06:33  CONTAINER ID        IMAGE                          COMMAND                  CREATED             STATUS              PORTS                                                                                    NAMES
13:06:33  b909ac695561        localstack/localstack:0.11.4   "docker-entrypoint.sh"   2 minutes ago       Up 2 minutes        4566-4568/tcp,4593-4597/tcp,0.0.0.0:4569-4592->4569-4592/tcp,0.0.0.0:8055->8080/tcp   localstack

docker网络检查localstack-network返回：

13:06:33  [
13:06:33      {
13:06:33          "Name": "localstack-network",13:06:33          "Id": "09994610b0d71dfc4fe0147bbc884a749362c3fb42397366591c73e3c10702eb",13:06:33          "Created": "2020-10-04T10:03:52.586816186Z",13:06:33          "Scope": "local",13:06:33          "Driver": "bridge",13:06:33          "EnableIPv6": false,13:06:33          "IPAM": {
13:06:33              "Driver": "default",13:06:33              "Options": null,13:06:33              "Config": [
13:06:33                  {
13:06:33                      "subnet": "100.66.0.0/16",13:06:33                      "Gateway": "100.66.0.1"
13:06:33                  }
13:06:33              ]
13:06:33          },13:06:33          "Internal": false,13:06:33          "Attachable": true,13:06:33          "Ingress": false,13:06:33          "ConfigFrom": {
13:06:33              "Network": ""
13:06:33          },13:06:33          "ConfigOnly": false,13:06:33          "Containers": {
13:06:33              "b909ac695561200c1ab43c70c9f25cd537622593b7eade03d16af89b70c97d76": {
13:06:33                  "Name": "localstack",13:06:33                  "EndpointID": "783e7aefbef801d7707d46f664b6adf329dceeee6108d23a36c63d5cb3a3fdae",13:06:33                  "MacAddress": "02:42:64:42:00:02",13:06:33                  "IPv4Address": "100.66.0.2/16",13:06:33                  "IPv6Address": ""
13:06:33              }
13:06:33          },13:06:33          "Options": {},13:06:33          "Labels": {
13:06:33              "com.docker.compose.network": "localstack-network",13:06:33              "com.docker.compose.project": "infra",13:06:33              "com.docker.compose.version": "1.24.1"
13:06:33          }
13:06:33      }
13:06:33  ]

docker-compose.yaml：

  services:
  localstack:
    image: localstack/localstack:0.11.4
    container_name: localstack
    networks:
      - localstack-network
    ports:
      - "4566-4597:4566-4597"
      - '8080:8080'
    environment:
      - SERVICES=lambda,stepfunctions,dynamodb,s3,sns
      - DEBUG=1
      - data_dir=/tmp/localstack/data
      - PORT_WEB_UI=${PORT_WEB_UI- }
      - LAMBDA_EXECUTOR=docker #${LAMBDA_EXECUTOR- docker-reuse}
      - DOCKER_HOST=unix:///var/run/docker.sock
      - LAMBDA_REMOTE_DOCKER=true
      - LAMBDA_REMOVE_CONTAINERS=true
    volumes:
      - "/tmp${TMPDIR:-/tmp/localstack}:/tmp/localstack"
      - "/var/run/docker.sock:/var/run/docker.sock"

解决方法

在localstack中运行的Lambda实际上是在容器中执行的，因此您有一个在另一个容器（localstack）中运行的容器（Lambda），因此Lambda如果需要与其他localstack服务（例如DynamoDB）进行通信，则需要知道localstack地址。

在您的Lambda函数中，获取localstack地址并将其用于用于创建DynamoDB客户端实例的配置对象中-这是一个C＃示例：

var serviceURL = $@"http://{Environment.GetEnvironmentVariable("LOCALSTACK_HOSTNAME")}:4569";

您的Lambda无法连接到本地堆栈可能还有其他原因，请随时使用docker / docker-compose yaml设置文件和函数本身扩展您的问题，如果您仍然愿意的话，我可能会为您提供进一步的帮助卡住了。

PS：由于您使用的是最新版本，因此您也可以为所有localstack服务切换到单个端口4566。

docker docker localstack