无法使用 docker-compose 连接到 Postgresql 数据库的应用程序

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我正在尝试使用 docker-compose 运行我的 web 应用程序。

我的dockerfile

from golang:1.15

workdir /goprojects/vnlist

copy . .

run go get github.com/revel/revel
run go get github.com/revel/cmd/revel
run go get -d -v ./...

expose 9000

cmd [ "revel", "run", "-a", "vnlist" ]

我的docker-compose.yml

version: '3.3'
services:
  web:
    build: .
    ports: 
      - "9000:9000"
  db:
    image: "postgres"
    environment: 
      postgres_user: "postgres"
      postgres_password: "postgresql123"
      postgres_db: "vnlist_db"
    volumes: 
      - db-data:/foo

volumes: 
  db-data:

dbsetup 文件

package models

import (
    "fmt"

    "gorm.io/driver/postgres"
    "gorm.io/gorm"
)

var db *gorm.db

var (
    db_host     = "localhost"
    db_port     = "5432"
    db_user     = "postgres"
    db_password = "postgresql123"
    db_name     = "vnlist_db"
    db_timezone = "asia/jakarta"
)

func initdb() {
    dsn := fmt.sprintf("host=%s port=%s user=%s password=%s dbname=%s sslmode=disable",
        db_host, db_port, db_user, db_password, db_name)
    db, err := gorm.open(postgres.open(dsn), &gorm.config{})
    if err != nil {
        fmt.println("db error: ", err)
    }

    db.automigrate(&vn{}, &user{})

    db = db
}

然后，我运行了 docker-compose up --build。这是命令的结果：

Successfully built 1239cf1fceea
Successfully tagged vnlist_web:latest
Creating vnlist_db_1 ... done
Creating vnlist_web_1 ... done
Attaching to vnlist_db_1, vnlist_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 default max_connections ... 100
db_1   | selecting default shared_buffers ... 128MB
db_1   | selecting default timezone ... Etc/UTC
db_1   | selecting dynamic shared memory implementation ... posix
db_1   | creating configuration files ... ok
web_1  | Revel executing: run a Revel application
db_1   | running bootstrap script ... ok
db_1   | performing post-bootstrap initialization ... ok
db_1   | syncing data to disk ... ok
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   |
db_1   | 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   | waiting for server to start....2021-01-18 14:25:35.070 UTC [47] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
db_1   | 2021-01-18 14:25:35.437 UTC [48] LOG:  database system was shut down at 2021-01-18 14:25:30 UTC
db_1   | 2021-01-18 14:25:35.530 UTC [47] LOG:  database system is ready to accept connections
db_1   |  done
db_1   | server started
web_1  | WARN  14:25:35 harness.go:175: No http.addr specified in the app.conf listening on localhost interface only. This will not allow external access 
to your application
web_1  | Changed detected, recompiling
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   | waiting for server to shut down....2021-01-18 14:25:39.271 UTC [47] LOG:  received fast shutdown request
db_1   | 2021-01-18 14:25:39.420 UTC [47] LOG:  aborting any active transactions
db_1   | 2021-01-18 14:25:39.424 UTC [47] LOG:  background worker "logical replication launcher" (PID 54) exited with exit code 1
db_1   | 2021-01-18 14:25:39.424 UTC [49] LOG:  shutting down
db_1   | .2021-01-18 14:25:41.059 UTC [47] 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   | 2021-01-18 14:25:41.178 UTC [1] LOG:  listening on IPv4 address "0.0.0.0", port 5432
db_1   | 2021-01-18 14:25:41.178 UTC [1] LOG:  listening on IPv6 address "::", port 5432
db_1   | 2021-01-18 14:25:41.445 UTC [1] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
db_1   | 2021-01-18 14:25:41.906 UTC [75] LOG:  database system was shut down at 2021-01-18 14:25:40 UTC
db_1   | 2021-01-18 14:25:42.031 UTC [1] LOG:  database system is ready to accept connections
web_1  | Parsing packages, (may require download if not cached)... Completed
web_1  | INFO  14:27:12    app     run.go:35: Running revel server
web_1  | INFO  14:27:12    app   plugin.go:9: Go to /@tests to run the tests.
web_1  | 
web_1  | 2021/01/18 14:27:12 /goprojects/vnlist/app/models/DbSetup.go:24
web_1  | [error] failed to initialize database, got error failed to connect to `host=localhost user=postgres database=vnlist_db`: dial error (dial tcp [::1]:5432: connect: cannot assign requested address)
web_1  | DB Error:  failed to connect to `host=localhost user=postgres database=vnlist_db`: dial error (dial tcp [::1]:5432: connect: cannot assign requested address)
web_1  | 
web_1  | 2021/01/18 14:27:12 /root/go/pkg/mod/gorm.io/driver/[email protected]/migrator.go:157 failed to connect to `host=localhost user=postgres database=vnlist_db`: dial error (dial tcp [::1]:5432: connect: cannot assign requested address)
web_1  | [0.659ms] [rows:0] CREATE TABLE "vns" ("id" bigserial,"created_at" timestamptz,"updated_at" timestamptz,"deleted_at" timestamptz,"title" text,"genre" text,"original_language" text,"translated" boolean,PRIMARY KEY ("id"))
web_1  | 
web_1  | 2021/01/18 14:27:12 /root/go/pkg/mod/gorm.io/driver/[email protected]/migrator.go:130 failed to connect to `host=localhost user=postgres database=vnlist_db`: dial error (dial tcp [::1]:5432: connect: cannot assign requested address)
web_1  | [1.093ms] [rows:0] CREATE INDEX "idx_vns_deleted_at" ON "vns" ("deleted_at")
web_1  | Revel engine is listening on.. localhost:35495
web_1  |
web_1  | Time to recompile 1m36.9527518s
web_1  | Revel proxy is listening, point your browser to : 9000

正如我们在最后几行看到的，数据库无法连接。

我尝试更改数据库的凭据，但问题仍然存在。

我的问题是，如何解决这个问题？

解决方案

您的 DB_HOST 将是数据库服务 DB_HOST = "db" 而不是 "localhost" 的名称

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