tempestas

commit f15c48a2e40cc62921919f9d60b4e412840de4bb
parent 3f892c246b1f5257a2d9829c9ffa99f4d997e96c
Author: Chris Bracken <chris@bracken.jp>
Date:   Thu, 11 Nov 2021 14:16:36 -0800

Ensure DB connection is up at connect time

sql.Open doesn't guarantee that the database can be connected to; just
that it was able to create the sql.DB object. To ensure that we can
connect to the database, we now ping the database immediately after
sql.Open.

Diffstat:
M
storage/storage.go
 | 
11
+++++++++++

1 file changed, 11 insertions(+), 0 deletions(-)
diff --git a/storage/storage.go b/storage/storage.go
@@ -1,6 +1,7 @@
 package storage
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
 	"time"
@@ -21,10 +22,20 @@ type DataStore struct {
 func Connect(dbname string, user string, password string) *DataStore {
 	var s = new(DataStore)
 	var err error
+
+	// Create the database object. A nil error does not guarantee the DB is connected.
 	dbinfo := fmt.Sprintf("user=%s password=%s dbname=%s sslmode=disable", user, password, dbname)
 	if s.db, err = sql.Open("postgres", dbinfo); err != nil {
 		panic("Error connecting to database")
 	}
+
+	// Ping the DB to verify we can connect.
+	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+	defer cancel()
+	if err := s.db.PingContext(ctx); err != nil {
+		panic("Error connecting to database")
+	}
+
 	return s
 }