无法从应用容器连接到 postgres DB docker 容器答案

【问题标题】：Can’t connect from app container to postgresDB docker container无法从应用容器连接到 postgres DB docker 容器
【发布时间】：2019-11-15 05:26:45
【问题描述】：

我目前在使用 docker 并在其中运行时将节点项目与 Postgres 连接时遇到一些问题。

我已经问过一个相关问题，请参阅link，但是，我无法解决 nodeJs 和 postgres 之间的连接问题。

我的 docker-compose 文件如下所示：

# docker-compose.yml
version: "2.1"

services:
  app:
    build: .
    ports:
      - "49160:8080"
    networks:
      - webnet
    depends_on:
      db:
        condition: service_healthy
    environment:
      DATABASE_URL: postgres://postgres:taskin@db:5432/mydb


  db:
    image: kartoza/postgis:9.6-2.4
    networks: 
      - webnet
    environment:
      - POSTGRES_DB=mydb
      - POSTGRES_USER=postgres
      - POSTGRES_PASSWORD=mypassword
      - POSTGRES_MULTIPLE_EXTENSIONS=postgis,pgrouting
      - ALLOW_IP_RANGE=0.0.0.0/0
    volumes:
      - pgdata:/var/lib/postgresql/data

    restart: on-failure
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 10s
      timeout: 5s
      retries: 5

networks:
  webnet:

volumes:
  pgdata: {}

我的 Dockerfile 有以下输入：

#node 8
FROM node:8

#Create app directory
WORKDIR /usr/src/app

#Install app dependencies
COPY package*.json ./

RUN npm install

#Bundle app source
COPY . . 

EXPOSE 8080

CMD ["npm", "start"]

我的 nodeJS-express 服务器有以下设置：

var pg = require('pg');
var conString = process.env.DATABASE_URL || "postgres://postgres:mypassword@db:5432/mydb";

var client = new pg.Client(conString);

client.connect()

当我运行 docker-compose up 时

我首先收到密码验证错误：我可以通过编辑 pg_hba.conf 和 postgresql.conf 来解决此问题，如此链接中所述 link
重新启动 PostgreSQL 并更改 postgres 用户的密码后，我将 SQL 备份文件恢复到容器内的 mydb 中
然后我停止了之前的 docker-compose 命令并再次执行了sudo docker-compose up。获取以下输出

db_1_56896493481e | 
db_1_56896493481e | postgres conf already configured
db_1_56896493481e | ssl already configured
db_1_56896493481e | pg_hba  already configured
db_1_56896493481e | Setup master database
db_1_56896493481e | 2019-07-04 18:21:23.452 UTC [22] LOG:  database system was interrupted; last known up at 2019-07-04 18:14:49 UTC
db_1_56896493481e | 2019-07-04 18:21:23.470 UTC [30] postgres@postgres FATAL:  the database system is starting up
db_1_56896493481e | psql: FATAL:  the database system is starting up
db_1_56896493481e | 2019-07-04 18:21:23.508 UTC [22] LOG:  database system was not properly shut down; automatic recovery in progress
db_1_56896493481e | 2019-07-04 18:21:23.511 UTC [22] LOG:  redo starts at 0/28ECC738
db_1_56896493481e | 2019-07-04 18:21:23.511 UTC [22] LOG:  invalid record length at 0/28ECC770: wanted 24, got 0
db_1_56896493481e | 2019-07-04 18:21:23.511 UTC [22] LOG:  redo done at 0/28ECC738
db_1_56896493481e | 2019-07-04 18:21:23.520 UTC [22] LOG:  MultiXact member wraparound protections are now enabled
db_1_56896493481e | 2019-07-04 18:21:23.522 UTC [35] LOG:  autovacuum launcher started
db_1_56896493481e | 2019-07-04 18:21:23.522 UTC [17] LOG:  database system is ready to accept connections
db_1_56896493481e |                                  List of databases
db_1_56896493481e |        Name       |  Owner   | Encoding | Collate |  Ctype  |   Access privileges   
db_1_56896493481e | ------------------+----------+----------+---------+---------+-----------------------
db_1_56896493481e |  postgres         | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e |  mydb  | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e |  template0        | postgres | UTF8     | C.UTF-8 | C.UTF-8 | =c/postgres          +
db_1_56896493481e |                   |          |          |         |         | postgres=CTc/postgres
db_1_56896493481e |  template1        | postgres | UTF8     | C.UTF-8 | C.UTF-8 | =c/postgres          +
db_1_56896493481e |                   |          |          |         |         | postgres=CTc/postgres
db_1_56896493481e |  template_postgis | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e | (5 rows)
db_1_56896493481e | 
db_1_56896493481e | postgres ready
db_1_56896493481e | Postgis Already There
db_1_56896493481e | HSTORE is only useful when you create the postgis database.
db_1_56896493481e | TOPOLOGY is only useful when you create the postgis database.
db_1_56896493481e | Setup postgres User:Password
db_1_56896493481e | ALTER ROLE
db_1_56896493481e | Check default db exists
db_1_56896493481e | mydb db already exists
db_1_56896493481e |                                  List of databases
db_1_56896493481e |        Name       |  Owner   | Encoding | Collate |  Ctype  |   Access privileges   
db_1_56896493481e | ------------------+----------+----------+---------+---------+-----------------------
db_1_56896493481e |  postgres         | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e |  mydb  | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e |  template0        | postgres | UTF8     | C.UTF-8 | C.UTF-8 | =c/postgres          +
db_1_56896493481e |                   |          |          |         |         | postgres=CTc/postgres
db_1_56896493481e |  template1        | postgres | UTF8     | C.UTF-8 | C.UTF-8 | =c/postgres          +
db_1_56896493481e |                   |          |          |         |         | postgres=CTc/postgres
db_1_56896493481e |  template_postgis | postgres | UTF8     | C.UTF-8 | C.UTF-8 | 
db_1_56896493481e | (5 rows)
db_1_56896493481e | 
db_1_56896493481e | 2019-07-04 18:21:24.742 UTC [17] LOG:  received smart shutdown request
db_1_56896493481e | 2019-07-04 18:21:24.742 UTC [35] LOG:  autovacuum launcher shutting down
db_1_56896493481e | 2019-07-04 18:21:24.743 UTC [32] LOG:  shutting down
db_1_56896493481e | 2019-07-04 18:21:24.847 UTC [17] LOG:  database system is shut down
db_1_56896493481e | 
db_1_56896493481e | /docker-entrypoint.sh: ignoring /docker-entrypoint-initdb.d/*
db_1_56896493481e | 
db_1_56896493481e | Postgres initialisation process completed .... restarting in foreground
db_1_56896493481e | 2019-07-04 18:21:25.886 UTC [129] LOG:  database system was shut down at 2019-07-04 18:21:24 UTC
db_1_56896493481e | 2019-07-04 18:21:25.888 UTC [129] LOG:  MultiXact member wraparound protections are now enabled
db_1_56896493481e | 2019-07-04 18:21:25.891 UTC [133] LOG:  autovacuum launcher started
db_1_56896493481e | 2019-07-04 18:21:25.891 UTC [126] LOG:  database system is ready to accept connections
app_1_a393ffc30f68 | 
app_1_a393ffc30f68 | > node-api-postgres@1.0.0 start /usr/src/app
app_1_a393ffc30f68 | > node index.js
app_1_a393ffc30f68 | 
app_1_a393ffc30f68 | Running on http://0.0.0.0:8080

【问题讨论】：

app_1_ca885d4626de | wait-for-it.sh: waiting 15 seconds for db:5432: 也许再等一下，因为第一个错误发生在db_1_ceb54072343c | 2019-07-04 12:23:14.921 UTC [18] LOG: database system is ready to accept connections 之前大约 1 秒？
现在我收到另一个错误消息：Error: connect ECONNREFUSED 172.20.0.2:5432
另外，根据this，您可以使用healthcheck（从未使用过），主要是depends_on。当您运行它时，最好将此 wait-for-it.sh 逻辑移动到作曲家。
你等了多久？我想说，要验证错误确实来自数据库未准备好，您应该等待 120 秒（当 Node 启动时，您的日志不应再显示与 db 相关的内容，这样您就确定了问题是否来自两个容器之间缺乏同步）。
我删除了 tha wait-for-it.sh 命令，并在我的 docker compose 文件中将其替换为 depends_on: db，但仍然得到 Error: getaddrinfo ENOTFOUND db db:5432

标签： node.js postgresql docker docker-compose postgis

【解决方案1】：

在尝试了很多之后，我可以修复它。我的 docker-compose 文件是正确的，我的 ajax request 没有正确定义。改变后

 $.ajax({
    url: 'http://db:8080/show',
    type: "POST",
    data: CoordjsonObject,
    dataType: "json",
    success: function(data) {
      addStreetsLayer(data);
      console.log("worked!")
      },   
    error: function(xhr) {
      console.log(xhr)
      }
  });

到

 $.ajax({
    url: 'http://IP-ADRESS-OF-NODE-CONTAINER:8080/show',
    type: "POST",
    data: CoordjsonObject,
    dataType: "json",
    success: function(data) {
      addStreetsLayer(data);
      console.log("worked!")
      },   
    error: function(xhr) {
      console.log(xhr)
      }
  });

【讨论】：