moved DB into seperate module

1 files changed, 131 insertions, 0 deletions

diff --git a/src/helsinki.at/rhimport/rddb.go b/src/helsinki.at/rhimport/rddb.go
new file mode 100644
index 0000000..2a87388
--- /dev/null
+++ b/src/helsinki.at/rhimport/rddb.go
@@ -0,0 +1,131 @@
+//
+//  rhimportd
+//
+//  The Radio Helsinki Rivendell Import Daemon
+//
+//
+//  Copyright (C) 2015 Christian Pointner <equinox@helsinki.at>
+//
+//  This file is part of rhimportd.
+//
+//  rhimportd is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  any later version.
+//
+//  rhimportd is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with rhimportd. If not, see <http://www.gnu.org/licenses/>.
+//
+
+package rhimport
+
+import (
+	"database/sql"
+	"fmt"
+	_ "github.com/go-sql-driver/mysql"
+)
+
+type getPasswordResult struct {
+	password string
+	err      error
+}
+
+type getPasswordRequest struct {
+	username string
+	cached   bool
+	response chan getPasswordResult
+}
+
+type RDDB struct {
+	dbh               *sql.DB
+	password_cache    map[string]string
+	getPasswordChan   chan getPasswordRequest
+	dbGetPasswordStmt *sql.Stmt
+	quit              chan bool
+	done              chan bool
+}
+
+func (self *RDDB) init(conf *Config) (err error) {
+	dsn := fmt.Sprintf("%s:%s@tcp(%s:3306)/%s", conf.db_user, conf.db_passwd, conf.db_host, conf.db_db)
+	if self.dbh, err = sql.Open("mysql", dsn); err != nil {
+		return
+	}
+	if self.dbGetPasswordStmt, err = self.dbh.Prepare("select PASSWORD from USERS where LOGIN_NAME = ?"); err != nil {
+		return
+	}
+
+	return
+}
+
+func (self *RDDB) getPassword(username string, cached bool) (pwd string, err error) {
+
+	if cached {
+		pwd = self.password_cache[username]
+	}
+
+	if pwd == "" {
+		err = self.dbGetPasswordStmt.QueryRow(username).Scan(&pwd)
+		if err != nil {
+			if err == sql.ErrNoRows {
+				err = fmt.Errorf("user '%s' not known by rivendell", username)
+			}
+			return
+		}
+		self.password_cache[username] = pwd
+	}
+
+	return
+}
+
+func (self *RDDB) dispatchRequests() {
+	defer func() { self.done <- true }()
+	for {
+		select {
+		case <-self.quit:
+			return
+		case req := <-self.getPasswordChan:
+			if req.cached {
+				rhdl.Println("RDDB: got getPassword request for", req.username, "(cached)")
+			} else {
+				rhdl.Println("RDDB: got getPassword request for", req.username, "(not cached)")
+			}
+			pwd, err := self.getPassword(req.username, req.cached)
+			req.response <- getPasswordResult{pwd, err}
+		}
+	}
+}
+
+func (self *RDDB) Cleanup() {
+	self.quit <- true
+	<-self.done
+	close(self.quit)
+	close(self.done)
+	close(self.getPasswordChan)
+	if self.dbh != nil {
+		self.dbh.Close()
+	}
+	if self.dbGetPasswordStmt != nil {
+		self.dbGetPasswordStmt.Close()
+	}
+}
+
+func NewRDDB(conf *Config) (db *RDDB, err error) {
+	db = new(RDDB)
+
+	db.quit = make(chan bool)
+	db.done = make(chan bool)
+	db.password_cache = make(map[string]string)
+	db.getPasswordChan = make(chan getPasswordRequest)
+
+	if err = db.init(conf); err != nil {
+		return
+	}
+
+	go db.dispatchRequests()
+	return
+}