go vendor

vendor/github.com/revel/modules/db/app/db.go

@@ -0,0 +1,94 @@
+// Copyright (c) 2012-2016 The Revel Framework Authors, All rights reserved.
+// Revel Framework source code and usage is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+// Package db module configures a database connection for the application.
+//
+// Developers use this module by importing and calling db.Init().
+// A "Transactional" controller type is provided as a way to import interceptors
+// that manage the transaction
+//
+// In particular, a transaction is begun before each request and committed on
+// success.  If a panic occurred during the request, the transaction is rolled
+// back.  (The application may also roll the transaction back itself.)
+package db
+
+import (
+	"database/sql"
+
+	"github.com/revel/revel"
+)
+
+// Database connection variables
+var (
+	Db     *sql.DB
+	Driver string
+	Spec   string
+)
+
+// Init method used to initialize DB module on `OnAppStart`
+func Init() {
+	// Read configuration.
+	var found bool
+	if Driver, found = revel.Config.String("db.driver"); !found {
+		revel.RevelLog.Fatal("db.driver not configured")
+	}
+	if Spec, found = revel.Config.String("db.spec"); !found {
+		revel.RevelLog.Fatal("db.spec not configured")
+	}
+
+	// Open a connection.
+	var err error
+	Db, err = sql.Open(Driver, Spec)
+	if err != nil {
+		revel.RevelLog.Fatal("Open database connection error", "error", err, "driver", Driver, "spec", Spec)
+	}
+}
+
+// Transactional definition for database transaction
+type Transactional struct {
+	*revel.Controller
+	Txn *sql.Tx
+}
+
+// Begin a transaction
+func (c *Transactional) Begin() revel.Result {
+	txn, err := Db.Begin()
+	if err != nil {
+		panic(err)
+	}
+	c.Txn = txn
+	return nil
+}
+
+// Rollback if it's still going (must have panicked).
+func (c *Transactional) Rollback() revel.Result {
+	if c.Txn != nil {
+		if err := c.Txn.Rollback(); err != nil {
+			if err != sql.ErrTxDone {
+				panic(err)
+			}
+		}
+		c.Txn = nil
+	}
+	return nil
+}
+
+// Commit the transaction.
+func (c *Transactional) Commit() revel.Result {
+	if c.Txn != nil {
+		if err := c.Txn.Commit(); err != nil {
+			if err != sql.ErrTxDone {
+				panic(err)
+			}
+		}
+		c.Txn = nil
+	}
+	return nil
+}
+
+func init() {
+	revel.InterceptMethod((*Transactional).Begin, revel.BEFORE)
+	revel.InterceptMethod((*Transactional).Commit, revel.AFTER)
+	revel.InterceptMethod((*Transactional).Rollback, revel.FINALLY)
+}