widgets/data_source/GenericDataSource.inc

<?php
/**
 * This file contains the GenericDataSource child class
 * that may use arbitrary code modules as database handlers.
 * It's aims are to get together:
 *   o phpHtmlLibs "source-handlers"
 *   o PEAR's database handlers 
 *   o custom ones (e.g. Data::Driver::Proxy object, which talks to a remote rpc server)
 *
 * @author Andreas Motl <andreas.motl@ilo.de>
 * @package phpHtmlLib
 * @module GenericDataSource
 *
 */

/**
 * $Id: GenericDataSource.inc,v 1.2 2003/03/02 01:05:13 joko Exp $
 *
 * $Log: GenericDataSource.inc,v $
 * Revision 1.2  2003/03/02 01:05:13  joko
 * - purged old code
 *
 * Revision 1.1  2003/03/01 21:47:15  joko
 * renamed from AbstractDataSource.inc
 *
 * Revision 1.1  2003/03/01 20:17:15  joko
 * renamed from GenericDataSource.inc
 * replaced '_proxy' through '_handler' to better associate the ability to act as a generic dispatcher handler
 *
 * Revision 1.3  2003/03/01 15:36:11  joko
 * + debugging
 * + renamed some methods regarding new proposal (build_handler_options, fetch_result, etc.)
 *
 * Revision 1.2  2003/03/01 04:50:27  joko
 * encapsulated all output into tracing mode
 * disabled tracing
 *
 * Revision 1.1  2003/03/01 03:10:40  joko
 * + initial commit
 *
 *
 */

/**
 * This requires the MemoryDataSource base class
 *
 */
  // V1: compile-time-include, stable since years  ;-)
  include_once($phphtmllib."/widgets/data_source/MemoryDataSource.inc");
  // V2: runtime-load proposal, more flexible
  // loadModule('MemoryDataSource', 'inc');   // doesn't work (would do if basepath of module is in libpath)
  // loadModule($phphtmllib . '::widgets::data_source::MemoryDataSource', 'inc');   // works  (by accident)
  // loadModule($phphtmllib . "/widgets/data_source/MemoryDataSource", "inc");   // works  (should be stable)
  // loadModule($phphtmllib . "/widgets/data_source/MemoryDataSource.inc", null);   // works  (should be stable)
  

/**
 * Have to have PEAR and DB included
 * the pear dir must be in the 
 * include path.
 */
  // require_once("PEAR.php");   // FIXME: what about PEAR::XML::RPC?
  // require_once("DB.php");

/**
 * This GenericDataSource child class is *completely* independent
 * of a specific storage implementation and intended to be a wrapper
 * class on the way from phpHtmlLib to Xyz.
 *    ("Yyz" gets represented by Data::Storage by now.....)
 *
 * GenericDataSource interacts with an intermediate "proxy" object 
 * (e.g. Data::Driver::Proxy) when doing queries.
 *    Don't mix this up with a persistent database handle which gets
 *    reused each and every time for different queries.
 *    Here *is* a new instance of Data::Driver::Proxy for *each* query.
 *
 * But the point is: Caching! The actual *data* isn't read redundant!
 *
 *
 * !!!!!!  refactor this to Data::Driver::Proxy  !!!!!!     <-----------------
 *
 * Data::Driver::Proxy instantiates "handlers" below itself
 * which act as encapsulated workers to actually do the stuff to do.
 * It can cache data for "disconnected mode" using the
 * php PEAR DB abstraction objects.
 * One worker already implemented is Data::Driver::RPC::Remote, which
 * talks to a RPC::XML server (todo: talk SOAP!) using PEAR::XML::RPC.
 *
 * ---  refactored here, but: redundant somehow  ---
 * Data::Driver::Proxy uses a PEAR XML::RPC object to actually
 * talk HTTP and serialize data chunks to and from XML,
 * but adds some caching to this "process of fetching data from a remote side".
 * It "proxies" arbitrary data chunks a) inside a native php4 session, 
 * b) by talking to a rdbms (single proxy-table) or c) [TODO] using PEAR::Cache.
 * ---  refactored here, but: redundant somehow  ---
 *
 * !!!!!!  refactor this to Data::Driver::Proxy  !!!!!!     <-----------------
 *
 *
 * How to use?
 *
 * Pass an array holding "locator metadata" to the constructor.
 * GenericDataSource takes care of the rest.
 *
 * Pass an array to the constructor: (e.g.)
 *
 *  1. doing rpc-calls....
 *    $locator = array(
 *      type => 'rpc',
 *      metadata => array( Host => 'localhost', Port => '8765' ),
 *    );
 *    $source = new GenericDataSource($locator);
 *    $this->set_data_source( &$source );
 *
 *  2. [proposal] common datahandles....
 *    $locator = array(
 *      type => 'mysql',
 *      dsn => 'known dsn markup',
 *    );
 *    $source = new GenericDataSource($locator);
 *    $this->set_data_source( &$source );
 *
 * @author Andreas Motl <andreas.motl@ilo.de>
 * @author Sebastian Utz <seut@tunemedia.de>
 * @copyright (c) 2003 - All Rights reserved.
 * @license GNU LGPL (GNU Lesser General Public License)
 *
 * @author-url http://www.netfrag.org/~joko/
 * @author-url http://www.netfrag.org/~jonen/
 * @license-url http://www.gnu.org/licenses/lgpl.txt
 *
 * @package phpHtmlLib
 * @module GenericDataSource
 *
 */

/**
 * Todo:
 *
 *  o mungle this to be able to be wrapped around phpHtmlLib's own storage-handles
 *  o implement another Data::Driver::Proxy container
 *
 */


//loadModule('DesignPattern::Proxy');
loadModule('DesignPattern::RemoteProxy');

//class GenericDataSource extends MemoryDataSource {
//class GenericDataSource extends DesignPattern_Proxy {
class GenericDataSource extends DesignPattern_RemoteProxy {

        /**
         * This var holds the locator metadata hash
         * that is used to feed metadata to a per-query-instance
         * of a Data::Driver::Proxy object.
         *
         */
        var $_locator = NULL;


        /**
         * This var holds the query hash
         * that is used to feed as query to a per-query-instance
         * of a Data::Driver::Proxy object.
         *
         */
        var $_query = NULL;


        /**
         * this holds the query result from the
         * Data::Driver::Proxy->queryXyz() call
         *
         */
        var $_result = NULL;


        /**
         * The constructor is used to pass in the
         * locator metadata hash.
         *
         * @param LocatorMetadataHash array - layout: array( type => '', metadata => '', dsn => '' )
         * @param Query array - layout: array( type => '', metadata => '', dsn => '' )
         */
        function GenericDataSource( &$locator, $query ) {
                
                $this->set_locator( $locator );
                $this->set_query( $query );
        }
        
        /**
     * Set the locator metadata hash we will feed *partly*
     * to an encapsulated Data::Driver::Proxy instance.
     *
     * @param LocatorMetadataHash array - 
     *
     */
    function set_locator( &$locator ) {
        $this->_locator = &$locator;
    }

        /**
     * Set the query metadata hash we will feed *completely*
     * to an encapsulated Data::Driver::Proxy instance.
     *
     * @param QueryDeclaration array - 
     *
     */
    function set_query( $query ) {
        $this->_query = $query;
    }

        /**
     * Issue remote/proxy call
     * Stolen from Application_AbstractBackend::_remote_method (RefactoringProposal?)
     * Tweaked a bit: proxy package now taken from $this->_handler_name
     *
     * Create a new instance of a proxy and store it for later reuse.
     * Read the locator metadata hash and create 
     * the proxy handler instance using passed-in name.
     *
     * @param string - $proxy_name (namespaced classname - perl syntax - e.g.: Data::Driver::Proxy)
     *
     */
    function call_handler() {


      // 1. read args

        $arg_list = func_get_args();
        $command = array_shift($arg_list);
        $cache_key = join("-", array(session_id(), $command, join('_', $arg_list) ));
        //print "cache_key: $cache_key<br>";
  
        // FIXME: what if arg_list still contains more elements after doing this?
        $query = array_shift($arg_list);


      // 2. prepare proxy-options

        // read from locator metadata
          $proxy_name = $this->_locator[metadata][package];
          $rpcinfo = array( Host => $this->_locator[metadata][Host], Port => $this->_locator[metadata][Port] );

        // FIXME! implement this into Data::Driver::RPC::Remote!
          //$rpcinfo[to_latin] = 1;
          
        // FIXME! patch query
        if (sizeof($query) == 1) {
          $query = $query[0];
        }

      //  !!! use DesignPattern::Proxy here !!!
      // $proxy = new DesignPattern_Proxy($proxy_name, ...)
      // or:
      // $proxy = mkObject('DesignPattern::Proxy');
      // $this->set_handler( $proxy );
      // or:
      // $proxy = mkObject('DesignPattern::Proxy');
      // $proxy->
      // $this->set_handler( $proxy );
      
      $this->set_component_name( $proxy_name );
      $this->set_component_options( $cache_key, array( key => 1, command => $command, query => $query, remote => 1, rpcinfo => $rpcinfo, cache => array( db => 0, session => 1 ) ) );
      
      $this->create_handler();
      
      /*
      // --------------------   clone this & modify  ----------
      $proxy = mkObject($proxy_name, $cache_key, array( key => 1, command => $command, query => $query, remote => 1, rpcinfo => $rpcinfo, cache => array( db => 0, session => 1 ) ) );
      $this->set_handler( $proxy );
      //$result = $resultHandle->getAttributes();
      //return $result;
      //$this->_result = $resultHandle->getAttributes();
      //$this->_result = $this->_handler->getAttributes();
      // --------------------   clone this & modify  ----------
      */
  
    }


        function build_handler_options() {

      //print Dumper($this->_query);
      //exit;

      // make up a command from metadata
      // FIXME: abstract this some more (e.g. via a CommandMapper|Registry)
        switch ($this->_query[metatype]) {
          case 'data':
            //$command = 'queryData';
            $command = 'getObjects';   // FIXME!!!
            $args = array();
            switch ($this->_query[vartype]) {
              case 'object':
                if (!$this->_query[classname]) {
                  $msg = "_query[vartype] == 'object' requires _query[classname]";
                  user_error("GenericDataSource::do_query() - failed: " . $msg);
                }
                array_push($args, $this->_query[classname]);
                break;
            }
            break;
          case 'schema':
            $command = 'querySchema';
            break;
        }
      
      // trace
        $this->debug(null, '<b>= = = = = = = = = = = = = = = = = = = = = =</b>');
        $this->trace('build_handler_options', array(
          "_locator" => $this->_locator,
          "_query" => $this->_query,
          "command" => '<b>' . $command . "</b>",
          "args" => $args
        ));

    $this->_handler_options = array(
      method => $command,
      args => $args,
    );
      
  }

        function fetch_result() {
      
      $this->build_handler_options();
      $method = $this->_handler_options[method];
      $args = $this->_handler_options[args];
      
      // pre-flight checks
        if (!$method) {
          $msg = "Remote command could not be resolved, please pass in or check configuration.";
                        user_error("GenericDataSource::do_query() - failed: " . $msg);
          return;
        }

      // do remote call here and get result
      // FIXME: handle synchronous/asynchronous mode here!!!
        $this->call_handler($method, $args);
        // TODO: ... = $this->poll_handler_result  and  $this->get_handler_result
        $this->_result = $this->_handler->getAttributes();

      // trace
        if ($this->_debug[notice]) {
          //print "_result = " . Dumper($this->_result);
          print "_result - count = " . sizeof($this->_result) . "<br/>";
        }

        }


  function do_query() {
    //print "query!<br/>";
    $this->fetch_result();
    $this->handle_result();
  }

  function do_query_schema() {
    user_error("FIXME: do_query_schema");
    // $this->call_handler( ... );
  }
        
  function get_header() {
    $this->fetch_result();
    $this->read_labels_from_result();
    return $this->get_labels();
  }


}

?>
1	joko	1.1	<?php
2			/**
3			* This file contains the GenericDataSource child class
4			* that may use arbitrary code modules as database handlers.
5			* It's aims are to get together:
6			* o phpHtmlLibs "source-handlers"
7			* o PEAR's database handlers
8			* o custom ones (e.g. Data::Driver::Proxy object, which talks to a remote rpc server)
9			*
10			* @author Andreas Motl <andreas.motl@ilo.de>
11			* @package phpHtmlLib
12			* @module GenericDataSource
13			*
14			*/
15
16			/**
17	joko	1.3	* $Id: GenericDataSource.inc,v 1.2 2003/03/02 01:05:13 joko Exp $
18	joko	1.2	*
19			* $Log: GenericDataSource.inc,v $
20	joko	1.3	* Revision 1.2 2003/03/02 01:05:13 joko
21			* - purged old code
22			*
23	joko	1.2	* Revision 1.1 2003/03/01 21:47:15 joko
24			* renamed from AbstractDataSource.inc
25	joko	1.1	*
26			* Revision 1.1 2003/03/01 20:17:15 joko
27			* renamed from GenericDataSource.inc
28			* replaced '_proxy' through '_handler' to better associate the ability to act as a generic dispatcher handler
29			*
30			* Revision 1.3 2003/03/01 15:36:11 joko
31			* + debugging
32			* + renamed some methods regarding new proposal (build_handler_options, fetch_result, etc.)
33			*
34			* Revision 1.2 2003/03/01 04:50:27 joko
35			* encapsulated all output into tracing mode
36			* disabled tracing
37			*
38			* Revision 1.1 2003/03/01 03:10:40 joko
39			* + initial commit
40			*
41			*
42			*/
43
44			/**
45			* This requires the MemoryDataSource base class
46			*
47			*/
48			// V1: compile-time-include, stable since years ;-)
49			include_once($phphtmllib."/widgets/data_source/MemoryDataSource.inc");
50			// V2: runtime-load proposal, more flexible
51			// loadModule('MemoryDataSource', 'inc'); // doesn't work (would do if basepath of module is in libpath)
52			// loadModule($phphtmllib . '::widgets::data_source::MemoryDataSource', 'inc'); // works (by accident)
53			// loadModule($phphtmllib . "/widgets/data_source/MemoryDataSource", "inc"); // works (should be stable)
54			// loadModule($phphtmllib . "/widgets/data_source/MemoryDataSource.inc", null); // works (should be stable)
55
56
57
58			/**
59			* Have to have PEAR and DB included
60			* the pear dir must be in the
61			* include path.
62			*/
63			// require_once("PEAR.php"); // FIXME: what about PEAR::XML::RPC?
64			// require_once("DB.php");
65
66			/**
67			* This GenericDataSource child class is completely independent
68			* of a specific storage implementation and intended to be a wrapper
69			* class on the way from phpHtmlLib to Xyz.
70			* ("Yyz" gets represented by Data::Storage by now.....)
71			*
72			* GenericDataSource interacts with an intermediate "proxy" object
73			* (e.g. Data::Driver::Proxy) when doing queries.
74			* Don't mix this up with a persistent database handle which gets
75			* reused each and every time for different queries.
76			* Here is a new instance of Data::Driver::Proxy for each query.
77			*
78			* But the point is: Caching! The actual data isn't read redundant!
79			*
80			*
81			* !!!!!! refactor this to Data::Driver::Proxy !!!!!! <-----------------
82			*
83			* Data::Driver::Proxy instantiates "handlers" below itself
84			* which act as encapsulated workers to actually do the stuff to do.
85			* It can cache data for "disconnected mode" using the
86			* php PEAR DB abstraction objects.
87			* One worker already implemented is Data::Driver::RPC::Remote, which
88			* talks to a RPC::XML server (todo: talk SOAP!) using PEAR::XML::RPC.
89			*
90			* --- refactored here, but: redundant somehow ---
91			* Data::Driver::Proxy uses a PEAR XML::RPC object to actually
92			* talk HTTP and serialize data chunks to and from XML,
93			* but adds some caching to this "process of fetching data from a remote side".
94			* It "proxies" arbitrary data chunks a) inside a native php4 session,
95			* b) by talking to a rdbms (single proxy-table) or c) [TODO] using PEAR::Cache.
96			* --- refactored here, but: redundant somehow ---
97			*
98			* !!!!!! refactor this to Data::Driver::Proxy !!!!!! <-----------------
99			*
100			*
101			* How to use?
102			*
103			* Pass an array holding "locator metadata" to the constructor.
104			* GenericDataSource takes care of the rest.
105			*
106			* Pass an array to the constructor: (e.g.)
107			*
108			* 1. doing rpc-calls....
109			* $locator = array(
110			* type => 'rpc',
111			* metadata => array( Host => 'localhost', Port => '8765' ),
112			* );
113			* $source = new GenericDataSource($locator);
114			* $this->set_data_source( &$source );
115			*
116			* 2. [proposal] common datahandles....
117			* $locator = array(
118			* type => 'mysql',
119			* dsn => 'known dsn markup',
120			* );
121			* $source = new GenericDataSource($locator);
122			* $this->set_data_source( &$source );
123			*
124			* @author Andreas Motl <andreas.motl@ilo.de>
125			* @author Sebastian Utz <seut@tunemedia.de>
126			* @copyright (c) 2003 - All Rights reserved.
127			* @license GNU LGPL (GNU Lesser General Public License)
128			*
129			* @author-url http://www.netfrag.org/~joko/
130			* @author-url http://www.netfrag.org/~jonen/
131			* @license-url http://www.gnu.org/licenses/lgpl.txt
132			*
133			* @package phpHtmlLib
134			* @module GenericDataSource
135			*
136			*/
137
138			/**
139			* Todo:
140			*
141			* o mungle this to be able to be wrapped around phpHtmlLib's own storage-handles
142			* o implement another Data::Driver::Proxy container
143			*
144			*/
145
146
147	joko	1.3	//loadModule('DesignPattern::Proxy');
148			loadModule('DesignPattern::RemoteProxy');
149
150			//class GenericDataSource extends MemoryDataSource {
151			//class GenericDataSource extends DesignPattern_Proxy {
152			class GenericDataSource extends DesignPattern_RemoteProxy {
153	joko	1.1
154			/**
155			* This var holds the locator metadata hash
156			* that is used to feed metadata to a per-query-instance
157			* of a Data::Driver::Proxy object.
158			*
159			*/
160			var $_locator = NULL;
161
162
163			/**
164			* This var holds the query hash
165			* that is used to feed as query to a per-query-instance
166			* of a Data::Driver::Proxy object.
167			*
168			*/
169			var $_query = NULL;
170
171
172			/**
173			* this holds the query result from the
174			* Data::Driver::Proxy->queryXyz() call
175			*
176			*/
177			var $_result = NULL;
178
179
180
181			/**
182			* The constructor is used to pass in the
183			* locator metadata hash.
184			*
185			* @param LocatorMetadataHash array - layout: array( type => '', metadata => '', dsn => '' )
186			* @param Query array - layout: array( type => '', metadata => '', dsn => '' )
187			*/
188			function GenericDataSource( &$locator, $query ) {
189
190			$this->set_locator( $locator );
191			$this->set_query( $query );
192			}
193
194			/**
195			* Set the locator metadata hash we will feed partly
196			* to an encapsulated Data::Driver::Proxy instance.
197			*
198			* @param LocatorMetadataHash array -
199			*
200			*/
201			function set_locator( &$locator ) {
202			$this->_locator = &$locator;
203			}
204
205			/**
206			* Set the query metadata hash we will feed completely
207			* to an encapsulated Data::Driver::Proxy instance.
208			*
209			* @param QueryDeclaration array -
210			*
211			*/
212			function set_query( $query ) {
213			$this->_query = $query;
214			}
215
216			/**
217			* Issue remote/proxy call
218			* Stolen from Application_AbstractBackend::_remote_method (RefactoringProposal?)
219			* Tweaked a bit: proxy package now taken from $this->_handler_name
220			*
221			* Create a new instance of a proxy and store it for later reuse.
222			* Read the locator metadata hash and create
223			* the proxy handler instance using passed-in name.
224			*
225			* @param string - $proxy_name (namespaced classname - perl syntax - e.g.: Data::Driver::Proxy)
226			*
227			*/
228	joko	1.3	function call_handler() {
229	joko	1.1
230
231			// 1. read args
232
233			$arg_list = func_get_args();
234			$command = array_shift($arg_list);
235			$cache_key = join("-", array(session_id(), $command, join('_', $arg_list) ));
236			//print "cache_key: $cache_key<br>";
237
238			// FIXME: what if arg_list still contains more elements after doing this?
239			$query = array_shift($arg_list);
240
241
242			// 2. prepare proxy-options
243
244			// read from locator metadata
245			$proxy_name = $this->_locator[metadata][package];
246			$rpcinfo = array( Host => $this->_locator[metadata][Host], Port => $this->_locator[metadata][Port] );
247
248			// FIXME! implement this into Data::Driver::RPC::Remote!
249			//$rpcinfo[to_latin] = 1;
250
251			// FIXME! patch query
252			if (sizeof($query) == 1) {
253			$query = $query[0];
254			}
255	joko	1.3
256			// !!! use DesignPattern::Proxy here !!!
257			// $proxy = new DesignPattern_Proxy($proxy_name, ...)
258			// or:
259			// $proxy = mkObject('DesignPattern::Proxy');
260			// $this->set_handler( $proxy );
261			// or:
262			// $proxy = mkObject('DesignPattern::Proxy');
263			// $proxy->
264			// $this->set_handler( $proxy );
265
266			$this->set_component_name( $proxy_name );
267			$this->set_component_options( $cache_key, array( key => 1, command => $command, query => $query, remote => 1, rpcinfo => $rpcinfo, cache => array( db => 0, session => 1 ) ) );
268
269			$this->create_handler();
270	joko	1.1
271	joko	1.3	/*
272	joko	1.1	// -------------------- clone this & modify ----------
273			$proxy = mkObject($proxy_name, $cache_key, array( key => 1, command => $command, query => $query, remote => 1, rpcinfo => $rpcinfo, cache => array( db => 0, session => 1 ) ) );
274			$this->set_handler( $proxy );
275			//$result = $resultHandle->getAttributes();
276			//return $result;
277			//$this->_result = $resultHandle->getAttributes();
278			//$this->_result = $this->_handler->getAttributes();
279			// -------------------- clone this & modify ----------
280	joko	1.3	*/
281	joko	1.1
282			}
283
284
285			function build_handler_options() {
286
287			//print Dumper($this->_query);
288			//exit;
289
290			// make up a command from metadata
291			// FIXME: abstract this some more (e.g. via a CommandMapper\|Registry)
292			switch ($this->_query[metatype]) {
293			case 'data':
294			//$command = 'queryData';
295			$command = 'getObjects'; // FIXME!!!
296			$args = array();
297			switch ($this->_query[vartype]) {
298			case 'object':
299			if (!$this->_query[classname]) {
300			$msg = "_query[vartype] == 'object' requires _query[classname]";
301			user_error("GenericDataSource::do_query() - failed: " . $msg);
302			}
303			array_push($args, $this->_query[classname]);
304			break;
305			}
306			break;
307			case 'schema':
308			$command = 'querySchema';
309			break;
310			}
311
312			// trace
313			$this->debug(null, '<b>= = = = = = = = = = = = = = = = = = = = = =</b>');
314			$this->trace('build_handler_options', array(
315			"_locator" => $this->_locator,
316			"_query" => $this->_query,
317			"command" => '<b>' . $command . "</b>",
318			"args" => $args
319			));
320
321			$this->_handler_options = array(
322			method => $command,
323			args => $args,
324			);
325
326			}
327
328			function fetch_result() {
329
330			$this->build_handler_options();
331			$method = $this->_handler_options[method];
332			$args = $this->_handler_options[args];
333
334			// pre-flight checks
335			if (!$method) {
336			$msg = "Remote command could not be resolved, please pass in or check configuration.";
337			user_error("GenericDataSource::do_query() - failed: " . $msg);
338			return;
339			}
340
341			// do remote call here and get result
342			// FIXME: handle synchronous/asynchronous mode here!!!
343	joko	1.3	$this->call_handler($method, $args);
344	joko	1.1	// TODO: ... = $this->poll_handler_result and $this->get_handler_result
345			$this->_result = $this->_handler->getAttributes();
346
347			// trace
348			if ($this->_debug[notice]) {
349			//print "_result = " . Dumper($this->_result);
350			print "_result - count = " . sizeof($this->_result) . "<br/>";
351			}
352
353			}
354
355
356			function do_query() {
357			//print "query!<br/>";
358			$this->fetch_result();
359			$this->handle_result();
360			}
361	joko	1.2
362			function do_query_schema() {
363			user_error("FIXME: do_query_schema");
364	joko	1.3	// $this->call_handler( ... );
365	joko	1.2	}
366	joko	1.1
367			function get_header() {
368			$this->fetch_result();
369			$this->read_labels_from_result();
370			return $this->get_labels();
371			}
372
373
374
375
376			}
377
378			?>
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