我想要通过docker-compose来连接一个Go语言和PostgreSQL容器。
以下是我的docker-compose.yml文件:
version: '2'
services:
postgres:
image: postgres
ports:
- "5432"
environment:
- POSTGRES_PASSWORD=postgres
server:
build: ./server
command: gin
volumes:
- ./server:/go/src/app
ports:
- "8080:3000"
起初我尝试在docker-compose.yml中使用links命令，但是这并没有在服务器容器中创建任何环境变量，这让我感到非常困惑。(它应该会创建 SOMETHINGSOMETHING_PORT_5432_TCP_ADDR 和 SOMETHINGSOMETHING_5432_TCP_PORT，不是吗？)
然后我在某个地方读到可以直接使用http://postgres作为主机，所以我尝试了一下。现在我的main.go看起来是这样的（注意：我正在使用Gorp作为“ORM”）:
func main() {
dbinfo := fmt.Sprintf("user=%s password=%s host=%s dbname=%s sslmode=disable",
"postgres",
os.Getenv("DB_ENV_POSTGRES_PASSWORD"),
"http://postgres",
DB_NAME,
)
db, err := sql.Open("postgres", dbinfo)
checkErr(err, "sql.Open failed")
// construct a gorp DbMap
dbmap := &gorp.DbMap{Db: db, Dialect: gorp.PostgresDialect{}}
// add a table, setting the table name to 'posts' and
// specifying that the Id property is an auto incrementing PK
dbmap.AddTableWithName(Todo{}, "todos").SetKeys(true, "Id")
// create the table. in a production system you'd generally
// use a migration tool, or create the tables via scripts
err = dbmap.CreateTablesIfNotExists()
checkErr(err, "Create tables failed")
http.HandleFunc("/", handler)
http.ListenAndServe(":3001", nil)
}
这是一个关于docker-compose up详细日志的记录（我在端口5432上遇到了连接被拒绝的问题）。
←[36mserver_1 |←[0m [gin] listening on port 3000
←[33mpostgres_1 |←[0m The files belonging to this database system will be owned by user "postgres".
←[33mpostgres_1 |←[0m This user must also own the server process.
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m The database cluster will be initialized with locale "en_US.utf8".
←[33mpostgres_1 |←[0m The default database encoding has accordingly been set to "UTF8".
←[33mpostgres_1 |←[0m The default text search configuration will be set to "english".
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m Data page checksums are disabled.
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m fixing permissions on existing directory /var/lib/postgresql/data ... ok
←[33mpostgres_1 |←[0m creating subdirectories ... ok
←[33mpostgres_1 |←[0m selecting default max_connections ... 100
←[33mpostgres_1 |←[0m selecting default shared_buffers ... 128MB
←[33mpostgres_1 |←[0m selecting dynamic shared memory implementation ... posix
←[33mpostgres_1 |←[0m creating configuration files ... ok
←[33mpostgres_1 |←[0m creating template1 database in /var/lib/postgresql/data/base/1 ... ok
←[33mpostgres_1 |←[0m initializing pg_authid ... ok
←[33mpostgres_1 |←[0m initializing dependencies ... ok
←[33mpostgres_1 |←[0m creating system views ... ok
←[33mpostgres_1 |←[0m loading system objects' descriptions ... ok
←[33mpostgres_1 |←[0m creating collations ... ok
←[33mpostgres_1 |←[0m creating conversions ... ok
←[33mpostgres_1 |←[0m creating dictionaries ... ok
←[33mpostgres_1 |←[0m setting privileges on built-in objects ... ok
←[33mpostgres_1 |←[0m creating information schema ... ok
←[33mpostgres_1 |←[0m loading PL/pgSQL server-side language ... ok
←[33mpostgres_1 |←[0m vacuuming database template1 ... ok
←[33mpostgres_1 |←[0m copying template1 to template0 ... ok
←[33mpostgres_1 |←[0m copying template1 to postgres ... ok
←[33mpostgres_1 |←[0m syncing data to disk ... ok
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m WARNING: enabling "trust" authentication for local connections
←[33mpostgres_1 |←[0m You can change this by editing pg_hba.conf or using the option -A, or
←[33mpostgres_1 |←[0m --auth-local and --auth-host, the next time you run initdb.
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m Success. You can now start the database server using:
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m pg_ctl -D /var/lib/postgresql/data -l logfile start
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m waiting for server to start....LOG: database system was shut down at 2016-08-19 18:31:55 UTC
←[33mpostgres_1 |←[0m LOG: MultiXact member wraparound protections are now enabled
←[33mpostgres_1 |←[0m LOG: database system is ready to accept connections
←[33mpostgres_1 |←[0m LOG: autovacuum launcher started
←[33mpostgres_1 |←[0m done
←[33mpostgres_1 |←[0m server started
←[33mpostgres_1 |←[0m ALTER ROLE
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m /docker-entrypoint.sh: ignoring /docker-entrypoint-initdb.d/*
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m LOG: received fast shutdown request
←[33mpostgres_1 |←[0m LOG: aborting any active transactions
←[33mpostgres_1 |←[0m LOG: autovacuum launcher shutting down
←[33mpostgres_1 |←[0m LOG: shutting down
←[33mpostgres_1 |←[0m waiting for server to shut down....LOG: database system is shut down
←[33mpostgres_1 |←[0m done
←[33mpostgres_1 |←[0m server stopped
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m PostgreSQL init process complete; ready for start up.
←[33mpostgres_1 |←[0m
←[33mpostgres_1 |←[0m LOG: database system was shut down at 2016-08-19 18:31:57 UTC
←[33mpostgres_1 |←[0m LOG: MultiXact member wraparound protections are now enabled
←[33mpostgres_1 |←[0m LOG: database system is ready to accept connections
←[33mpostgres_1 |←[0m LOG: autovacuum launcher started
←[36mserver_1 |←[0m 2016/08/19 18:32:05 Create tables failed dial tcp [::1]:5432: getsockopt: connection refused
←[36mserver_1 |←[0m 2016/08/19 18:32:05 http: proxy error: dial tcp [::1]:3001: getsockopt: connection refused
←[36mserver_1 |←[0m 2016/08/19 18:32:05 Create tables failed dial tcp [::1]:5432: getsockopt: connection refused
←[36mserver_1 |←[0m 2016/08/19 18:32:05 http: proxy error: dial tcp [::1]:3001: getsockopt: connection refused
所以我的问题是，我该如何让它们彼此通信，我在这里做错了什么？
sql.Open("postgres", "postgres://postgres/yourdbname")- Plato