我知道这是一个典型的问题，但我需要社区的帮助来解决它。当我运行docker compose时，我得到连接被拒绝：服务器在主机上运行吗；db"；(172.21.0.2(，并在端口5432上接受web_1 TCP/IP连接？docker compose的Web部分失败，但数据库运行。我可以使用localhost:5432连接到数据库。这不是等待问题，因为tiangolo/uvicorn gunicorn:python3.8-alpine3.10实现了一个等待机制-dockerize。有人知道问题出在哪里吗？或者有人能给我指一个正确的方向吗？所以我的Dockerfile是
FROM tiangolo/uvicorn-gunicorn:python3.8-alpine3.10
# copy requirements file
COPY ./requirements.txt /usr/src/app/requirements.txt
# install dependencies
RUN set -eux
&& apk add --no-cache --virtual .build-deps build-base
libressl-dev libffi-dev gcc musl-dev python3-dev
postgresql-dev openssl
&& pip install --upgrade pip setuptools wheel
&& pip install -r /usr/src/app/requirements.txt
&& rm -rf /root/.cache/pip
# copy project
COPY . /app
我的docker作文是：
version: '3.7'
services:
db:
image: postgres:13-alpine
volumes:
- postgres_data:/var/lib/postgresql/data/
ports:
- 5432:5432
environment:
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=postgres
- POSTGRES_DB=api
web:
build: ./src
ports:
- 80:80
depends_on:
- db
environment:
- DATABASE_URL=postgresql://postgres:postgres@db/api
volumes:
postgres_data:
我使用dockerize添加了一个等待，但web部分失败：
Attaching to gunicorn_db_1, gunicorn_web_1
db_1 | The files belonging to this database system will be owned by user "postgres".
db_1 | This user must also own the server process.
db_1 |
db_1 | The database cluster will be initialized with locale "en_US.utf8".
db_1 | The default database encoding has accordingly been set to "UTF8".
db_1 | The default text search configuration will be set to "english".
db_1 |
db_1 | Data page checksums are disabled.
db_1 |
db_1 | fixing permissions on existing directory /var/lib/postgresql/data ... ok
db_1 | creating subdirectories ... ok
db_1 | selecting dynamic shared memory implementation ... posix
db_1 | selecting default max_connections ... 100
db_1 | selecting default shared_buffers ... 128MB
web_1 | 2020/08/30 15:33:51 Waiting for: tcp://db:5432
web_1 | 2020/08/30 15:33:51 Problem with dial: dial tcp 172.21.0.2:5432: connect: connection refused. Sleeping 30s
db_1 | selecting default time zone ... Etc/UTC
db_1 | creating configuration files ... ok
db_1 | running bootstrap script ... ok
db_1 | performing post-bootstrap initialization ... ok
db_1 | syncing data to disk ... initdb: warning: enabling "trust" authentication for local connections
db_1 | You can change this by editing pg_hba.conf or using the option -A, or
db_1 | --auth-local and --auth-host, the next time you run initdb.
db_1 | ok
db_1 |
db_1 |
db_1 | Success. You can now start the database server using:
db_1 |
db_1 | pg_ctl -D /var/lib/postgresql/data -l logfile start
db_1 |
db_1 | waiting for server to start....2020-08-30 15:33:53.037 UTC [45] LOG: starting PostgreSQL 13beta3 (Debian 13~beta3-1.pgdg100+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 8.3.0-6) 8.3.0, 64-bit
db_1 | 2020-08-30 15:33:53.044 UTC [45] LOG: listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
db_1 | 2020-08-30 15:33:53.059 UTC [46] LOG: database system was shut down at 2020-08-30 15:33:52 UTC
db_1 | 2020-08-30 15:33:53.066 UTC [45] LOG: database system is ready to accept connections
db_1 | done
db_1 | server started
db_1 | CREATE DATABASE
db_1 |
db_1 |
db_1 | /usr/local/bin/docker-entrypoint.sh: ignoring /docker-entrypoint-initdb.d/*
db_1 |
db_1 | 2020-08-30 15:33:53.399 UTC [45] LOG: received fast shutdown request
db_1 | waiting for server to shut down....2020-08-30 15:33:53.404 UTC [45] LOG: aborting any active transactions
db_1 | 2020-08-30 15:33:53.407 UTC [45] LOG: background worker "logical replication launcher" (PID 52) exited with exit code 1
db_1 | 2020-08-30 15:33:53.409 UTC [47] LOG: shutting down
db_1 | 2020-08-30 15:33:53.438 UTC [45] LOG: database system is shut down
db_1 | done
db_1 | server stopped
db_1 |
db_1 | PostgreSQL init process complete; ready for start up.
db_1 |
db_1 | 2020-08-30 15:33:53.530 UTC [1] LOG: starting PostgreSQL 13beta3 (Debian 13~beta3-1.pgdg100+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 8.3.0-6) 8.3.0, 64-bit
db_1 | 2020-08-30 15:33:53.531 UTC [1] LOG: listening on IPv4 address "0.0.0.0", port 5432
db_1 | 2020-08-30 15:33:53.531 UTC [1] LOG: listening on IPv6 address "::", port 5432
db_1 | 2020-08-30 15:33:53.539 UTC [1] LOG: listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
db_1 | 2020-08-30 15:33:53.549 UTC [63] LOG: database system was shut down at 2020-08-30 15:33:53 UTC
db_1 | 2020-08-30 15:33:53.559 UTC [1] LOG: database system is ready to accept connections
web_1 | 2020/08/30 15:34:21 Connected to tcp://db:5432
gunicorn_web_1 exited with code 0
乍一看，你的两个文件对我来说都很好，实际上添加一个取决于应该可以解决这个问题，但根据不起作用的文档。它表示容器之间的依赖关系，但这并不意味着一个容器将等待其他容器准备就绪。
对于Compose的旧版本，我们可以添加类似的健康检查
healthcheck:
test: ["-U postgres"]
interval: 3s
timeout: 30s
retries: 1
但由于它不再受支持，最好的选择是向该服务添加手动等待/睡眠。
有一个广泛使用的bash脚本(等待(，您可以使用它来测试和等待TCP主机和端口的可用性。它也是Compose文档中推荐的解决方案。您可以将等待它复制到您的文件中，然后立即开始使用它。
web:
command: /wait-for-it.sh db:5432
此外，您可能还想检查一下：等待docker使用
只需将Docker Compose的版本更改为："3.5〃；这就解决了的问题