Propel ORM - how do I specify tables to reverse engineer? - schema

Question

I have a database with a few dozen tables. My app deals with just one of those tables. I'd like propel to generate the schema just for that table. Is there a way I can specify the table(s) in build.properties?

Answer 1

A simple extension of Propel (code examples based on Propel-1.6.8) to allow ignore a custom set of tables (configured using a property):
Extend build-propel.xml:
<!-- Ignore Tables Feature -->
<taskdef
name="propel-schema-reverse-ignore"
classname="task.PropelSchemaReverseIgnoreTask" classpathRef="propelclasses"/>
Extend build.xml:
<target name="reverse-ignore" depends="configure">
<phing phingfile="build-propel.xml" target="reverse-ignore"/>
</target>
Extend PropelSchemaReverseTask:
class PropelSchemaReverseIgnoreTask extends PropelSchemaReverseTask {
/**
* Builds the model classes from the database schema.
* #return Database The built-out Database (with all tables, etc.)
*/
protected function buildModel()
{
// ...
// Loads Classname reverse.customParserClass if present
$customParserClassname = $config->getBuildProperty("reverseCustomParserClass");
if ($customParserClassname!=null) {
$this->log('Using custom parser class: '.$customParserClassname);
$parser = $config->getConfiguredSchemaParserForClassname($con, $customParserClassname);
} else {
$parser = $config->getConfiguredSchemaParser($con);
}
// ...
}
}
Add function to GeneratorConfig:
class GeneratorConfig implements GeneratorConfigInterface {
// ...
/**
* Ignore Tables Feature:
* Load a specific SchemaParser class
*
* #param PDO $con
* #param string $clazzName SchemaParser class to load
* #throws BuildException
* #return Ambigous <SchemaParser, unknown>
*/
public function getConfiguredSchemaParserForClassname(PDO $con = null, $clazzName)
{
$parser = new $clazzName();
if (!$parser instanceof SchemaParser) {
throw new BuildException("Specified platform class ($clazz) does implement SchemaParser interface.", $this->getLocation());
}
$parser->setConnection($con);
$parser->setMigrationTable($this->getBuildProperty('migrationTable'));
$parser->setGeneratorConfig($this);
return $parser;
}
}
Extend MysqlSchemaParser:
class MysqlSchemaIgnoreParser extends MysqlSchemaParser {
public function parse(Database $database, Task $task = null)
{
$this->addVendorInfo = $this->getGeneratorConfig()->getBuildProperty('addVendorInfo');
$stmt = $this->dbh->query("SHOW FULL TABLES");
// First load the tables (important that this happen before filling out details of tables)
$tables = array();
$configIgnoreTables = $this->getGeneratorConfig()->getBuildProperty("reverseIgnoreTables");
$tables_ignore_list = array();
$tables_ignore_list = explode(",", $configIgnoreTables);
if ($task) {
$task->log("Reverse Engineering Tables", Project::MSG_VERBOSE);
}
while ($row = $stmt->fetch(PDO::FETCH_NUM)) {
$name = $row[0];
$type = $row[1];
if (!in_array($name, $tables_ignore_list)) {
// ...
} else {
$task->log("Ignoring table: " .$name);
}
}
// ...
}
}
Add new (optional) properties to build.properties:
# Propel Reverse Custom Properties
propel.reverse.customParserClass=MysqlSchemaIgnoreParser
propel.reverse.ignoreTables = table1,table2

Answer 2

A solution could be to write your own schema parser that ignores certain tables. These tables to exclude could be read from a config file or so.
Take a look at the MysqlSchemaParser.php to get an idea of how such a parser works. You could extend such an existing parser and just override the parse() method. When tables are added, you would check them for exclusion/inclusion and only add them if they meet your subset criteria.
How to create custom propel tasks is described in the Propel cookbook.
Instead of invoking propel-gen reverse you would then invoke your customized reverse engineering task.
If done neatly, I'd find it worth being added as a contribution to the Propel project and you'd definitely deserve fame for that! :-)