Create postgres driver

.travis.yml

@@ -23,6 +23,13 @@ env:
     - MYSQL_HOST=127.0.0.1
     - MYSQL_PORT=3306
     - MYSQL_DATABASE=kamimai
+install:
+  - go get -d github.com/BurntSushi/toml
+  - go get -d github.com/go-sql-driver/mysql
+  - go get -d github.com/lib/pq
+  - go get -d github.com/stretchr/testify/assert
+  - go get -d gopkg.in/yaml.v2
+  - go get -u github.com/golang/lint/golint
 before_install:
   - mysql -e "CREATE DATABASE IF NOT EXISTS kamimai;" -uroot
   - make init

driver/init.go

@@ -8,4 +8,5 @@ const versionTableName = "schema_version"
 
 func init() {
 	core.RegisterDriver("mysql", &MySQL{})
+	core.RegisterDriver("postgres", &Postgres{})
 }

driver/postgres.go

@@ -0,0 +1,217 @@
+package driver
+
+import (
+	"bytes"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strings"
+	"sync"
+
+	"github.com/eure/kamimai/core"
+	"github.com/lib/pq"
+)
+
+type (
+	// Postgres driver object.
+	Postgres struct {
+		db *sql.DB
+		tx *sql.Tx
+		mu sync.Mutex
+	}
+)
+
+// Open is the first function to be called.
+// Check the dsn string and open and verify any connection
+// that has to be made.
+func (d *Postgres) Open(dsn string) error {
+	z := strings.SplitN(dsn, "postgres:", 2)
+	if len(z) != 2 {
+		return errors.New("invalid data source name of postgres")
+	}
+
+	db, err := sql.Open("postgres", z[1])
+	if err != nil {
+		return err
+	}
+	if err := db.Ping(); err != nil {
+		return err
+	}
+	d.db = db
+
+	return d.Version().Create()
+}
+
+// Close is the last function to be called.
+// Close any open connection here.
+func (d *Postgres) Close() error {
+	return d.db.Close()
+}
+
+// Ext returns the sql file extension used by path. The extension is the
+// suffix beginning at the final dot in the final element of path; it is
+// empty if there is no dot.
+func (d *Postgres) Ext() string {
+	return ".sql"
+}
+
+// Transaction starts a db transaction. The isolation level is dependent on the
+// driver.
+func (d *Postgres) Transaction(fn func(*sql.Tx) error) error {
+	d.mu.Lock()
+	defer func() {
+		d.tx = nil
+		d.mu.Unlock()
+	}()
+
+	tx, err := d.db.Begin()
+	if err != nil {
+		return err
+	}
+	d.tx = tx
+
+	// Procedure
+	if err := fn(d.tx); err != nil {
+		if rberr := d.tx.Rollback(); rberr != nil {
+			return rberr
+		}
+		return err
+	}
+
+	// Commit
+	if err := d.tx.Commit(); err != nil {
+		if rberr := d.tx.Rollback(); rberr != nil {
+			return rberr
+		}
+		return err
+	}
+
+	return nil
+}
+
+// Exec executes a query without returning any rows. The args are for any
+// placeholder parameters in the query.
+func (d *Postgres) Exec(query string, args ...interface{}) (sql.Result, error) {
+	if d.tx != nil {
+		return d.tx.Exec(query, args...)
+	}
+	return d.db.Exec(query, args...)
+}
+
+// Version returns a version interface.
+func (d *Postgres) Version() core.Version {
+	return d
+}
+
+// Migrate applies migration file.
+func (d *Postgres) Migrate(m *core.Migration) error {
+	b, err := m.Read()
+	if err != nil {
+		return err
+	}
+
+	stmts := bytes.Split(b, []byte(";"))
+	for _, stmt := range stmts {
+		query := strings.TrimSpace(string(stmt))
+		if len(query) == 0 {
+			continue
+		}
+		_, err = d.Exec(query)
+		if err != nil {
+			isWarn := strings.Contains(err.Error(), pq.Ewarning)
+			if !isWarn {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// Insert inserts the given migration version.
+func (d *Postgres) Insert(val uint64) error {
+	query := fmt.Sprintf(`INSERT INTO %s (version) VALUES (%d)`,
+		versionTableName, val)
+
+	_, err := d.Exec(query)
+	if err != nil {
+		isWarn := strings.Contains(err.Error(), pq.Ewarning)
+		if !isWarn {
+			return err
+		}
+	}
+	return nil
+}
+
+// Delete deletes the given migration version.
+func (d *Postgres) Delete(val uint64) error {
+	query := fmt.Sprintf(`DELETE FROM %s WHERE version = %d`,
+		versionTableName, val)
+
+	_, err := d.Exec(query)
+	if err != nil {
+		isWarn := strings.Contains(err.Error(), pq.Ewarning)
+		if !isWarn {
+			return err
+		}
+	}
+	return nil
+}
+
+// Count counts number of row the given migration version.
+func (d *Postgres) Count(val uint64) int {
+	query := fmt.Sprintf(`SELECT count(version) count FROM %s WHERE version = %d`,
+		versionTableName, val)
+
+	var count int
+	if err := d.db.QueryRow(query).Scan(&count); err != nil {
+		return 0
+	}
+	return count
+}
+
+// Current returns the current migration version.
+func (d *Postgres) Current() (uint64, error) {
+	const query = `SELECT version FROM ` +
+		versionTableName + ` ORDER BY version DESC LIMIT 1`
+
+	var version uint64
+	err := d.db.QueryRow(query).Scan(&version)
+	switch {
+	case err == sql.ErrNoRows:
+		return 0, nil
+	case err != nil:
+		return 0, err
+	}
+	return version, nil
+}
+
+// Create creates
+func (d *Postgres) Create() error {
+	const query = `CREATE TABLE IF NOT EXISTS ` +
+		versionTableName + ` (version BIGINT NOT NULL PRIMARY KEY);`
+
+	_, err := d.Exec(query)
+
+	if err != nil {
+		isWarn := strings.Contains(err.Error(), pq.Ewarning)
+		if !isWarn {
+			return err
+		}
+	}
+	return nil
+}
+
+// Drop drops
+func (d *Postgres) Drop() error {
+	const query = `DROP TABLE IF EXISTS ` + versionTableName
+
+	_, err := d.Exec(query)
+	if err != nil {
+		isWarn := strings.Contains(err.Error(), pq.Ewarning)
+		if !isWarn {
+			return err
+		}
+	}
+	return nil
+}

examples/postgres/config.tml

@@ -0,0 +1,8 @@
+[develop]
+driver = "postgres"
+dsn = "postgres:user=$POSTGRES_USER dbname=hogedb password=$POSTGRES_PASSWORD sslmode=disable"
+
+[test1]
+driver = "postgres"
+dsn = "postgres:user=$POSTGRES_USER dbname=hogedb password=$POSTGRES_PASSWORD sslmode=disable"
+directory = "test1"

examples/postgres/migrations/001_create_product_down.sql

@@ -0,0 +1 @@
+DROP TABLE product;

examples/postgres/migrations/001_create_product_up.sql

@@ -0,0 +1,4 @@
+CREATE TABLE product (
+    id int4 PRIMARY KEY,
+    name text
+);

examples/postgres/test1/001_create_product_down.sql

@@ -0,0 +1 @@
+DROP TABLE product;

examples/postgres/test1/001_create_product_up.sql

@@ -0,0 +1,4 @@
+CREATE TABLE product (
+    id int4 PRIMARY KEY,
+    name text
+);

examples/postgres/test1/002_insert_product_down.sql

@@ -0,0 +1 @@
+DELETE FROM product WHERE id in (1, 2);

examples/postgres/test1/002_insert_product_up.sql

@@ -0,0 +1 @@
+INSERT INTO product (id, name) VALUES (1, 'prod1'), (2, 'prod2');

examples/postgres/test1/003_insert_product_down.sql

@@ -0,0 +1 @@
+DELETE FROM product WHERE id in (3, 4);

examples/postgres/test1/003_insert_product_up.sql

@@ -0,0 +1 @@
+INSERT INTO product (id, name) VALUES (3, 'prod3'), (4, 'prod4');

glide.yaml

@@ -3,6 +3,7 @@ import:
 - package: github.com/BurntSushi/toml
 - package: github.com/go-sql-driver/mysql
 - package: gopkg.in/yaml.v2
+- package: github.com/lib/pq
 testImport:
 - package: github.com/stretchr/testify
   subpackages: