Serverless functions and PostgreSQL

I have been banging my head against the wall trying to get a serverless function to successfully connect to a PostgreSQL dev instance inn the App Platform.

Locally, I have pgAdmin installed, and no problems there.

My case is just a simple read operation, but with all the function runtimes (node:14, node:18, node-lambda:18, python:3.9 and go:1.17) and postgres drivers I just end up getting a timeout when opening the connection (both in the serverless development environment and on App Platform).

In each case I have tried slightly modifying the functions to run locally, and that works with no problems. I am getting a feeling that the port (25060) might not be open or something.

Anyway, I am hearing and reading all about how seamlessly integrated these serverless functions are with DO’s managed databases, but as far as I can see, there aren’t any docs/examples/guides (for any language) that cover serverless/PostgreSQL.

I’ll attach my latest attempt (with the sql statement redacted, replace with anything…), hoping someone can point out what I am doing wrong:

package main

import (
    "context"
    "errors"
    "fmt"
    "log"
    "net/http"
    "os"

    "github.com/jackc/pgx/v4"
)

type In struct {
    Id string `json:"id"`
}

type Out struct {
    StatusCode int               `json:"statusCode,omitempty"`
    Headers    map[string]string `json:"headers,omitempty"`
    Body       string            `json:"body,omitempty"`
}

var (
    connStr string
    ErrNoId = errors.New("no id provided!")
)

func init() {
    connStr = os.Getenv("PG_CONN")
    if connStr == "" {
        panic("No connection string (PG_CONN) provided!")
    }
}

func Main(in In) (*Out, error) {
    if in.Id == "" {
        return &Out{StatusCode: http.StatusBadRequest}, ErrNoId
    }

    db, err := pgx.Connect(context.Background(), connStr)

    if err != nil {
        log.Println(err)
        panic("Could not open connection to database!")
    }

    defer db.Close(context.Background())

    var version string

    var sql = `
        SELECT ...
    `

    err = db.QueryRow(context.Background(), sql, in.Id).Scan(&version)

    if err != nil {
        fmt.Println("No rows were returned!")
        version = "1.0.0"
    }

    return &Out{
        StatusCode: http.StatusOK,
        Body:       version,
    }, nil
}