I'm trying to set the time zone in my postgresql connection string in golang. I am using the following connection string (trying to set to the Australian Time Zone)
"host=%s port=%d user=%s password=%s dbname=%s sslmode=disable TimeZone=EST". However when I run this I get the following error
invalid value for parameter \"TimeZone\": \"AESST\""
As per the documentation here, this should be correct I believe
https://www.postgresql.org/docs/7.2/timezones.html
Related
I'm unable to connect an AWS SAM lambda function to a local postgres instance. I'll be specific in a moment, but first let me say that the same code works for my coworker and that I've tried using Postgres within a docker container as well as installed manually. To simplify the problem I started over with the SAM helloworld golang example and added the following:
import (
_ "github.com/lib/pq"
"database/sql"
)
.
.
.
const (
host = "localhost"
port = 5432
user = "postgres"
password = "postgres"
dbname = "postgres"
)
.
.
.
.
psqlInfo := fmt.Sprintf("host=%s port=%d user=%s "+
"password=%s dbname=%s sslmode=disable",
host, port, user, password, dbname)
db, err := sql.Open("postgres", psqlInfo)
if err != nil {
panic(err)
}
defer db.Close()
err = db.Ping()
if err != nil {
panic(err)
}
fmt.Println("Successfully connected!")
And I get the following error:
dial tcp 127.0.0.1:5432: connect: connection refused: OpError
[{"path":"github.com/aws/aws-lambda-go#v1.13.3/lambda/function.go","line":35,"label":"(*Function).Invoke.func1"},{"path":"runtime/panic.go","line":969,"label":"gopanic"},{"path":"hello-world/main.go","line":67,"label":"handler"},{"path":"reflect/value.go","line":475,"label":"Value.call"},{"path":"reflect/value.go","line":336,"label":"Value.Call"},{"path":"github.com/aws/aws-lambda-go#v1.13.3/lambda/handler.go","line":124,"label":"NewHandler.func1"},{"path":"github.com/aws/aws-lambda-go#v1.13.3/lambda/handler.go","line":24,"label":"lambdaHandler.Invoke"},{"path":"github.com/aws/aws-lambda-go#v1.13.3/lambda/function.go","line":67,"label":"(*Function).Invoke"},{"path":"reflect/value.go","line":475,"label":"V
alue.call"},{"path":"reflect/value.go","line":336,"label":"Value.Call"},{"path":"net/rpc/server.go","line":377,"label":"(*service).call"},{"path":"runtime/asm_amd64.s","line":1374,"label":"goexit"}]
SAM CLI, version 1.21.1
I've now tried this on two machines and get the same error. Is there there something that I'm just missing there? I can confirm that the the database is receiving connections fine. I hit it every day from a node app. Also, I can build the golang code outside of SAM and it will work fine. So there's something with my SAM setup that's wrong.
Figured it out. Within the lambda I needed to set the postgres connection string to hit host.docker.internal
I spend a lot of time figuring out how to connect using AWS SAM to a local Postgres and finally found that changing the dbhostname from localhost to host.docker.internal works.
connectionString = 'postgresql://dbuser:dbpassword#host.docker.internal:5432/dbname';
I have successfully connected to a Postgres database using the go sql package:
...
db, err := sql.Open("postgres", connStr)
I then use the returned database to execute a (long running) query:
rows, err := db.Query(...)
And am getting the error:
dial tcp xx.xxx.xxx.xx:5432: connect: connection timed out
I have a couple of questions regarding this:
why is the connection timing out?
is there anything I can do to prevent it timing out?
sql.Open() may just validate its arguments without creating a connection to
the database. To verify that the data source name is valid, call Ping.
The sql.Open() function has only created an object, your pool is currently empty. In simple words connection with the database hasn't been established yet.
You need to call db.Ping() to make sure your pool has a working connection.
I tried to connect to Google CloudSQL PostgresSQL using Gorm golang and seems like it is not working.
Here's the code
func InitDB() *gorm.DB {
psqlInfo := fmt.Sprintf("host=%s port=%s user=%s password=%s dbname=%s sslmode=disable", os.Getenv("DB_HOST"), os.Getenv("DB_PORT"), os.Getenv("DB_USER"), os.Getenv("DB_PASSWORD"), os.Getenv("DB_NAME"))
db, err := gorm.Open("postgres", psqlInfo)
if err != nil {
fmt.Println("Failed to connect to the Database")
}
fmt.Println("Connected to the Database")
DB = db
return DB
}
If im using the localhost config everything works fine. See my .env file for cloudSQL config
DB_HOST=trader-234509:us-central1:testv1
DB_PORT=5432
DB_USER=username
DB_NAME=testv1
DB_PASSWORD=
Error is saying
dial tcp: lookup trader-234509:us-central1:testv1: no such host
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x164681d]
My local config (This one works fine)
DB_HOST=localhost
DB_PORT=5432
DB_USER=username
DB_NAME=test
DB_PASSWORD=
Did i do anything wrong?
Here's roughly how I connect from AppEngine:
import (
_ "github.com/GoogleCloudPlatform/cloudsql-proxy/proxy/dialers/postgres"
"fmt"
"gorm.io/driver/postgres"
"gorm.io/gorm"
)
func New() (*gorm.DB, error) {
user := "theuser"
password := "apassword"
dbHost := "my-project:the-region:my-db-instance-name"
databaseName := "mydbname"
connString := fmt.Sprintf("host=%s user=%s dbname=%s sslmode=disable password=%s", dbHost, user, databaseName, password)
return gorm.Open(postgres.New(postgres.Config{
DriverName: "cloudsqlpostgres",
DSN: connString,
}))
}
Cloud SQL doesn't support direct connection to instance name for 3rd party application yet, for details: https://cloud.google.com/sql/docs/mysql/connect-external-app
Based on my experience, there are 2 solutions:
As per above instruction, you can setup a Cloud Proxy following the steps and the connections flow would be: Golang app -> Cloud Proxy -> Cloud SQL
This approach is flexible and you're able to control the connection using firewall.
But you have to spend extra $$ to maintain the server and this cloud proxy instance, I've also heard that the cloud proxy may have some performance issues but I don't have exact evidence so far
Assign a Private IP to the Cloud SQL instance, refer to https://cloud.google.com/sql/docs/mysql/private-ip, so that you application can access the DB directly using this IP.
The trade-off is obvious that the app must be in the same network of the project, but this is a much more convenient approach, esp. all your applications are hosted in the same network
I didn't try out the public IP access approach as Cloud Proxy is just what I need if remote network connection is needed
In short, you need to deploy your code in a VM or other Google Managed service using option 2, or setup the cloud proxy to support your local debugging for option 1
Hope it helps
I am looking to connect and query to a PostgreSQL. But I only want to connect to a particular Schema.
As per the doc (JDBC) we can use
jdbc:postgresql://localhost:5432/mydatabase?searchpath=myschema
or update As of 9.4 you can specify the url with the new currentSchema parameter like so:
jdbc:postgresql://localhost:5432/mydatabase?currentSchema=myschema
But I am unable to do so with golang SQL driver;
As per the documents, we can also use SET search_path TO myschema,public;
But I only want to declare it for once during initializing but I think this needs to be executed every time for new connection.
Also I am using following code please help me identify the correct parameters to be passed to this in order to only connect with schema
db, err := sql.Open("postgres", `dbname=`+s.settings.Database+
` user=`+s.settings.Username+` password=`+s.settings.Password+
` host=`+s.settings.Url+` sslmode=disable`)
Adding currentSchema=myschema or searchpath=myschema is not working!
Is there a way I can only connect to a particular database-schema in GO
You should add search_path=myschema to dataSourceName
P.S. better use fmt.Sprintf("host=%s port=%d dbname=%s user=%s password='%s' sslmode=disable search_path=%s", ...) instead ``+``
Set Search_path is right and you do it once. ie:
db, err := sql.Open("postgres",
"host=localhost dbname=Test sslmode=disable user=postgres password=secret")
if err != nil {
log.Fatal("cannot connect ...")
}
defer db.Close()
db.Exec(`set search_path='mySchema'`)
rows, err := db.Query(`select blah,blah2 from myTable`)
...
I'm writing a golang application and using the golang postgres driver - https://github.com/lib/pq/
I use a connection string like this
'name:pass#host:port/dbname'
I try to add aplication_name param in conn string, but this doesn't work
'name:pass#host:port/dbname?application_name=myapp'
Is it possible to set the application name from golang? (standard way)
Even though it's not mentioned in the documentation, if you look at the lib/pq source code you will find that application_name is supported.
This style connection works as desired:
connstring := fmt.Sprintf("user='%s' password='%s' dbname='%s' host='%s' application_name='%s'", user, password, dbname, host, application_name)
db, err := sql.Open("postgres", connstring)
If you look to the documentation a application_name option is not suuported. Maybe you could use:
fallback_application_name - An application_name to fall back to if
one isn't provided.
name:pass#host:port/dbname?fallback_application_name=myapp
You can set the application name one of two ways.
// Application name as space-separated list of options.
sql.Open("postgres", "user=myuser password=mypass host=localhost port=5432 dbname=mydb sslmode=disable application_name=myapp")
or
// Application name as query param.
sql.Open("postgres", "postgres://myuser:mypass#localhost:5432/mydb?sslmode=disable&application_name=myapp")