snippets

commit d9e6b2563a36ca59fdb41ee22ed2c1e50cdcc73d
parent f1a7d841bcae96c96867a5f9f29aae96eb5d81de
Author: Vetle Haflan <vetle@haflan.dev>
Date:   Fri, 29 Jul 2022 12:14:39 +0200

Add pgtester app - for testing Postgres connection

Diffstat:
A
pgtester/.gitignore
 | 
1
+
A
pgtester/build.sh
 | 
4
++++
A
pgtester/go.mod
 | 
5
+++++
A
pgtester/go.sum
 | 
2
++
A
pgtester/pgtester.go
 | 
50
++++++++++++++++++++++++++++++++++++++++++++++++++

5 files changed, 62 insertions(+), 0 deletions(-)
diff --git a/pgtester/.gitignore b/pgtester/.gitignore
@@ -0,0 +1 @@
+pgtester
diff --git a/pgtester/build.sh b/pgtester/build.sh
@@ -0,0 +1,4 @@
+#!/bin/bash
+GOOS=linux GOARCH=amd64 go build \
+    -a -tags=prod,osusergo,netgo,sqlite_omit_load_extension \
+    -ldflags '-s -w -extldflags "-static"' .
diff --git a/pgtester/go.mod b/pgtester/go.mod
@@ -0,0 +1,5 @@
+module pgtester
+
+go 1.18
+
+require github.com/lib/pq v1.10.6
diff --git a/pgtester/go.sum b/pgtester/go.sum
@@ -0,0 +1,2 @@
+github.com/lib/pq v1.10.6 h1:jbk+ZieJ0D7EVGJYpL9QTz7/YW6UHbmdnZWYyK5cdBs=
+github.com/lib/pq v1.10.6/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
diff --git a/pgtester/pgtester.go b/pgtester/pgtester.go
@@ -0,0 +1,50 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"os"
+	"strings"
+
+	_ "github.com/lib/pq"
+)
+
+const (
+	urlFmt   = "<user>:<password>@<host>/<database>[?sslmode=disable]\n"
+	testNum  = 3423
+	pgPrefix = "postgresql://"
+)
+
+func must(err error, msg string) {
+	if err == nil {
+		return
+	}
+	fmt.Println(msg+":", err)
+	os.Exit(1)
+}
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Printf("Use:\n\t%v [postgresql://]<database_url>\nURL format:\n\t%v", os.Args[0], urlFmt)
+		return
+	}
+	dbURL := pgPrefix + strings.TrimPrefix(os.Args[1], pgPrefix)
+	db, err := sql.Open("postgres", dbURL)
+	must(err, "Failed to open database:")
+	err = db.Ping()
+	must(err, "Failed to ping database")
+	_, err = db.Exec(`CREATE TABLE pgtester_temp_table (num int);`)
+	must(err, "Failed to create temporary table")
+	_, err = db.Exec(`INSERT INTO pgtester_temp_table VALUES ($1);`, testNum)
+	must(err, "Failed to insert into temporary table")
+	row := db.QueryRow(`SELECT num FROM pgtester_temp_table;`)
+	var readNum int
+	err = row.Scan(&readNum)
+	must(err, "Failed to read data from temporary table")
+	if readNum != testNum {
+		fmt.Printf("Inserted data does not match fetched data (%v != %v)\n", readNum, testNum)
+		os.Exit(1)
+	}
+	_, err = db.Exec(`DROP TABLE pgtester_temp_table;`)
+	must(err, "Failed to delete temporary database")
+}