Ticket #4760: mythtv-database_backup_using_script.patch

libs/libmyth/dbutil.h

@@ -42 +42 @@
                                  QString extension = ".sql");
     QString GetBackupDirectory();
 
-    bool DoBackup(QString &filename);
+    bool DoBackup(QString backupScript, QString &filename);
 
     QString m_versionString;
 

libs/libmyth/dbutil.cpp

@@ -157 +157 @@
 /** \fn DBUtil::BackupDB(QString)
  *  \brief Requests a backup of the database.
  *
+ *   If the DatabaseBackupScript exists in the ShareDir, it will be executed.
+ *   All required database information will be made available as name=value
+ *   pairs in a temporary file whose filename will be passed to the backup
+ *   script.  The script may parse this file to obtain the required information
+ *   to run a backup program, such as mysqldump or mysqlhotcopy.
+ *
  *   Care should be taken in calling this function.  It has the potential to
  *   corrupt in-progress recordings or interfere with playback.
  */
 bool DBUtil::BackupDB(QString &filename)
 {
+    QString backupScript = gContext->GetSetting("DatabaseBackupScript",
+                   gContext->GetShareDir() + "database_mythconverg_backup.sh");
+
+    if (!QFile::exists(backupScript))
+    {
+        VERBOSE(VB_IMPORTANT, LOC_ERR + QString("Database backup script does "
+                              "not exist: %1").arg(backupScript));
+        return false;
+    }
+
     bool result = false;
     MSqlQuery query(MSqlQuery::InitCon());
 
@@ -169 +185 @@
                                 QDateTime::currentDateTime()
                                 .toString("yyyy-MM-dd hh:mm:ss"), NULL);
 
-    result = DoBackup(filename);
+    result = DoBackup(backupScript, filename);
 
     gContext->SaveSettingOnHost("BackupDBLastRunEnd",
                                 QDateTime::currentDateTime()
@@ -288 +304 @@
     return directory;
 }
 
-/** \fn DBUtil::DoBackup(QString)
- *  \brief Creates a backup of the database.
+/** \fn DBUtil::DoBackup(QString, QString)
+ *  \brief Creates a backup of the database by executing the backupScript.
  */
-bool DBUtil::DoBackup(QString &filename)
+bool DBUtil::DoBackup(QString backupScript, QString &filename)
 {
     DatabaseParams dbParams = gContext->GetDatabaseParams();
     QString     dbSchemaVer = gContext->GetSetting("DBSchemaVer");
     QString backupDirectory = GetBackupDirectory();
+    QString  backupFilename = CreateBackupFilename(dbParams.dbName + "-" +
+                                                   dbSchemaVer, ".sql");
 
-    /* So we don't have to specify the password on the command line, use
-       --defaults-extra-file to specify a temporary file with a [client] and
-       [mysqldump] section that provides the password.  This will fail if the
-       user's ~/.my.cnf (which is read after the --defaults-extra-file)
-       specifies a different password that's incorrect for dbUserName */
-    QString tempExtraConfFile = QDeepCopy<QString>(
+    // Create a temporary file containing the database information
+    QString tempDatabaseConfFile = QDeepCopy<QString>(
                     createTempFile("/tmp/mythtv_db_backup_conf_XXXXXX"));
     FILE *fp;
-    if (!(fp = fopen(tempExtraConfFile.ascii(), "w")))
+    if (!(fp = fopen(tempDatabaseConfFile.ascii(), "w")))
     {
         VERBOSE(VB_IMPORTANT, LOC_ERR + QString("Unable to create temporary "
                 "configuration file for creating DB backup: %1")
-                .arg(tempExtraConfFile.ascii()));
-        VERBOSE(VB_IMPORTANT, LOC_ERR + QString("Attempting backup, anyway. "
-                "If the backup fails, please add the %1 user's database "
-                "password to your MySQL option file.")
-                .arg(dbParams.dbUserName));
+                .arg(tempDatabaseConfFile.ascii()));
+        VERBOSE(VB_IMPORTANT, LOC_ERR + "Attempting backup, anyway.");
+        tempDatabaseConfFile = "";
     }
     else
     {
-        chmod(tempExtraConfFile.ascii(), S_IRUSR);
-        fprintf(fp, QString("[client]\npassword=%1\n"
-                            "[mysqldump]\npassword=%2\n")
-                            .arg(dbParams.dbPassword).arg(dbParams.dbPassword));
+        chmod(tempDatabaseConfFile.ascii(), S_IRUSR);
+        fprintf(fp, QString("DBHostName=%1\n"
+                            "DBPort=%2\n")
+                            .arg(dbParams.dbHostName).arg(dbParams.dbPort));
+        fprintf(fp, QString("DBUserName=%1\n"
+                            "DBPassword=%2\n")
+                            .arg(dbParams.dbUserName).arg(dbParams.dbPassword));
+        fprintf(fp, QString("DBName=%1\n"
+                            "DBSchemaVer=%2\n")
+                            .arg(dbParams.dbName).arg(dbSchemaVer));
+        fprintf(fp, QString("DBBackupDirectory=%1\n"
+                            "DBBackupFilename=%2\n")
+                            .arg(backupDirectory)
+                            .arg(backupFilename));
         if (fclose(fp))
             VERBOSE(VB_IMPORTANT, LOC_ERR + QString("Error closing %1: %2")
-                    .arg(tempExtraConfFile.ascii()).arg(strerror(errno)));
+                    .arg(tempDatabaseConfFile.ascii()).arg(strerror(errno)));
     }
 
-    QString command;
-    QString compressCommand("");
-    QString extension = ".sql";
-    if (QFile::exists("/bin/gzip"))
-        compressCommand = "/bin/gzip";
-    else if (QFile::exists("/usr/bin/gzip"))
-        compressCommand = "/usr/bin/gzip";
-    else
-        VERBOSE(VB_IMPORTANT, "Neither /bin/gzip nor /usr/bin/gzip exist. "
-                              "The database backup will be uncompressed.");
-
-    QString backupPathname = backupDirectory + "/" +
-                             CreateBackupFilename(dbParams.dbName + "-" +
-                                                  dbSchemaVer, extension);
-    command = QString("mysqldump --defaults-extra-file='%1' --host='%2'"
-                      " --user='%3' --add-drop-table --add-locks"
-                      " --allow-keywords --complete-insert"
-                      " --extended-insert --lock-tables --no-create-db --quick"
-                      " '%4' > '%5' 2>/dev/null")
-                      .arg(tempExtraConfFile).arg(dbParams.dbHostName)
-                      .arg(dbParams.dbUserName).arg(dbParams.dbName)
-                      .arg(backupPathname);
-    VERBOSE(VB_FILE, QString("Backing up database with command: %1")
-                             .arg(command.ascii()));
-    VERBOSE(VB_IMPORTANT, QString("Backing up database to file: %1")
-            .arg(backupPathname.ascii()));
+    QString command = backupScript + " " + tempDatabaseConfFile;
+    VERBOSE(VB_IMPORTANT, QString("Backing up database with script: %1")
+            .arg(backupScript));
     uint status = system(command.ascii());
 
-    unlink(tempExtraConfFile.ascii());
+    unlink(tempDatabaseConfFile.ascii());
 
     if (status)
     {
@@ -365 +364 @@
         return false;
     }
 
-    if (compressCommand != "")
+    VERBOSE(VB_IMPORTANT, "Database Backup complete.");
+
+    QDir dir(backupDirectory, backupFilename + "*");
+    uint numfiles = dir.count();
+    if (numfiles < 1)
     {
-        VERBOSE(VB_IMPORTANT, "Compressing database backup file.");
-        compressCommand += " " + backupPathname;
-        status = system(compressCommand.ascii());
-
-        if (status)
-        {
-            VERBOSE(VB_IMPORTANT,
-                   "Compression failed, backup file will remain uncompressed.");
-        }
-        else
-        {
-            backupPathname += ".gz";
-
-            VERBOSE(VB_IMPORTANT, QString("Database Backup filename: %1")
-                    .arg(backupPathname.ascii()));
-        }
+        // If no file begins with the suggested filename, don't show the backup
+        // filename in the GUI message
+        filename = "";
+        VERBOSE(VB_FILE, LOC_ERR + QString("No files beginning with the "
+                "suggested database backup filename (%1) were found in %2.")
+                .arg(backupFilename).arg(backupDirectory));
     }
-
-    VERBOSE(VB_IMPORTANT, "Database Backup complete.");
-
-    filename = backupPathname;
+    else
+    {
+        filename = dir.path() + "/" + dir[0];;
+        if (numfiles > 1)
+            VERBOSE(VB_FILE, LOC_ERR + QString("Multiple files beginning with "
+                    "the suggested database backup filename (%1) were found "
+                    "in %2.  Assuming the first is the backup.")
+                    .arg(backupFilename).arg(backupDirectory));
+    }
+    if (!filename.isEmpty())
+        VERBOSE(VB_IMPORTANT, QString("Backed up database to file: %1")
+                .arg(filename));
     return true;
 }