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<?php |
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/** |
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* This file contains the DataSource::Locator class. |
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* |
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* It acts as a container for DataSource connection |
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* metadata. Think of it as an enhanced dsn. |
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* |
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* It gets used by DataSource::Generic |
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* to be informed about the most important stuff it |
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* has to do. |
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* |
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* |
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* @package org.netfrag.glib |
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* @module DataSource::Locator |
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* |
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*/ |
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|
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/** |
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* $Id: Locator.php,v 1.2 2003/03/05 15:01:10 joko Exp $ |
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* |
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* $Log: Locator.php,v $ |
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* Revision 1.2 2003/03/05 15:01:10 joko |
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* updated docu |
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* |
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* Revision 1.1 2003/03/05 12:04:37 joko |
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* + initial commit |
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* |
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* |
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*/ |
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|
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/** |
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* It helps DataSource::Generic working in different "operation modes". |
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* |
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* o Pass-Through-Reference: php Object will get passed through all layers |
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* o Pass-Through-Memory: reference to a memory area will get used |
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* + Build-Locator: build locator from datasource-type and adapter-type |
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* o Use-Locator: directly use DataSource::Locator instance passed in |
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* o Merge-Locators: merge metadata of two or more DataSource::Locator instances |
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* o Build-AutoLocator: use global constants making up our metadata |
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* |
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* |
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* <b>It can/should contain (flexible, just some parameters are required for each operation mode)</b> |
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* |
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* o an oldschool "dsn"-string (e.g. for rdbms-connection via PEAR) |
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* + name of a Proxy module to use to *wrap/hide* the connection/transport-layer |
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* (e.g. DataSource::Proxy::XMLRPC via DesignPattern::RemoteProxy) |
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* + metadata (a hash) directly describing *where* to connect to (e.g. 'Host', 'Port') |
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* o an instance of an already instantiated arbitrary datasource handler (e.g. 'source') |
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* this will get propagated (pass-through-mode) |
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* + a datasource-type (of 'rpc|mysql|csv-file|xml-file') |
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* this will be mapped to a module name and used as a *Proxy* |
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* by the DataSource::Generic at runtime |
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* + an adapter-type (of 'phpHtmlLib|pear') |
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* this will be mapped to a module name and used as an *Adapter* |
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* by the DataSource::Generic at runtime |
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* o names of global constants where to find these informations |
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* o datasource-type ('rpc|csv-file|...') <-> datasource-family ('orm|rdbms|odbms') |
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* |
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* |
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* --- It can do |
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* + builds a larger locator from a minimum of information passed in via constructor-arguments |
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* o direct fallback mode to some predefined constant names if locator is empty and above method fails |
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* o direct fallback mode to some predefined values if just *everything* fails |
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* |
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* |
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* --- How to use? |
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* |
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* Pass an array holding "locator metadata" to the constructor. |
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* This module takes care of the rest. |
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* |
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* Pass an array to the constructor: (e.g.) |
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* |
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* 1. for doing rpc-calls.... |
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* $locator = array( |
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* datasource_type => 'rpc', |
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* [adapter_type => 'phpHtmlLib',] |
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* metadata => array( Host => 'localhost', Port => '8765' ), |
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* ); |
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* $source = new DataSource::Generic($locator); |
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* $this->set_data_source( &$source ); |
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* |
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* 2. [proposal] for common/oldschool datahandles.... |
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* $locator = array( |
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* dsn => 'known dsn markup', |
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* ); |
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* $source = new DataSource::Generic($locator); |
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* $this->set_data_source( &$source ); |
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* |
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* |
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* |
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* @author Andreas Motl <andreas.motl@ilo.de> |
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* @link http://www.netfrag.org/~joko/ |
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* @copyright (c) 2003 - All Rights reserved. |
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* |
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* @license GNU LGPL (GNU Lesser General Public License) |
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* @link http://www.gnu.org/licenses/lgpl.txt |
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* |
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* @subpackage DataSource |
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* @name DataSource::Locator |
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* @filesource |
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* |
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*/ |
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|
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|
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class DataSource_Locator { |
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|
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/** |
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* This var holds the locator metadata hash |
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* which is built from some predefined rules |
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* using metadata from $_options and some |
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* other presets. |
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* |
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* See '_buildLocator' which acts as a dispatcher |
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* depending on $_options[datasource]. |
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* (main dispatching level) |
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* |
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* The structure of a full blown locator looks like this: |
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* |
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* $locator = array( |
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* type => '<your type specifying the datasource-type>', |
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* metadata => array( |
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* ... your arbitrary deep metadata structure ... |
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* ), |
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* [dsn => '<your dsn markup>'], |
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* ); |
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* |
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* Example 1 - data is inside a rdbms, using a dsn to connect to it: |
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* $locator = array( |
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* dsn => 'mysql://username:password@localhost/database', |
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* ); |
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* |
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* Example 2 - data is inside an odbms, reachable by doing remote procedure calls (rpc): |
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* $locator = array( |
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* type => 'rpc', |
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* metadata => array( |
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* package => 'Data::Driver::Proxy', |
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* Host => 'localhost', |
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* Port => '8765', |
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* ) |
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* ); |
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* |
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*/ |
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|
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//var $_locator_metadata = NULL; |
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|
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|
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/** |
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* This var holds the arguments passed in to the constructor. |
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* We will try to build full blown locator metadata information from that. |
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* |
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*/ |
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//var $_in = NULL; |
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|
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/** |
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* This var holds the locator metadata informations inside |
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* a single hash. This is returned from '->get()'. |
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* |
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*/ |
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//var $_out = NULL; |
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|
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|
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/** |
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* Locator metadata. |
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* |
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*/ |
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|
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// name of a Proxy module |
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var $_datasource_type; |
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|
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// name of an Adapter module |
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var $_adapter_type; |
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|
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// additional information required (passed on to the Proxy by DataSource::Generic) |
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var $_metadata = array(); |
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|
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//var $_dsn; |
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|
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|
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/** |
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* The constructor is used to pass in the |
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* locator metadata hash. |
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* |
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* @param LocatorMetadataHash array - layout: array( type => '', metadata => '', dsn => '' ) |
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* @param Query array - layout: array( type => '', metadata => '', dsn => '' ) |
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*/ |
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function DataSource_Locator() { |
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$args_multi = func_get_args(); |
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|
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//php::array_shrink($args_multi); |
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|
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//print Dumper($args_multi); |
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//exit; |
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|
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foreach ($args_multi as $args) { |
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if (isset($args)) { |
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$this->merge_args($args); |
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} |
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} |
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|
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$this->build(); |
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//$this->check(); |
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} |
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|
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function merge_args(&$args) { |
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|
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//print "args: " . Dumper($args); |
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|
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// check if passed in locator is already of type *me* ... |
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// ... if so, merge it into current instance |
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if (is_object($args) && get_class($args) == get_class($this)) { |
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$this->merge_to($this, $args); |
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|
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} else { |
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|
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// FIXME: handle locator merging here? |
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//$this->_arguments = &$args; |
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|
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// FIXME: to php::merge_to($this, $locator) here!!! |
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//$this->_data |
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// for now: assume plain hash, so just iterate and overwrite! |
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$this->merge_to($this, $args, '_'); |
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|
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} |
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} |
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|
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function merge_to(&$target, $source, $prefix_key = '') { |
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|
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//print "target: " . Dumper($target); |
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//print "source: " . Dumper($source); |
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|
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// pre-flight checks |
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if (!isset($target)) { |
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user_error("variable passed as reference (merge target) is not set."); |
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return; |
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} |
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//if (!is_hash($hash)) { |
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if (!isset($source)) { |
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user_error("variable passed as source is not set."); |
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return; |
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} |
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|
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// perform merge |
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foreach ($source as $key => $val) { |
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$name = $prefix_key . $key; |
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if (is_object($target)) { |
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$target->$name = $val; |
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//} elseif (php::is_hash($target)) { |
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} else { |
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$target[$name] = $val; |
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} |
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} |
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|
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// indicate good |
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return 1; |
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|
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} |
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|
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/** |
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* Set the locator metadata hash we will feed *partly* |
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* to an encapsulated Data::Driver::Proxy instance. |
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* |
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* @param LocatorMetadataHash array - |
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* |
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*/ |
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function set( &$locator ) { |
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$this->_out = &$locator; |
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} |
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|
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function &get_metadata() { |
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//return ($this->_out); |
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return $this->_metadata; |
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} |
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|
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|
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function build( ) { |
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|
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// trace |
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//print Dumper($this); |
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|
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$good = 0; |
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switch ($this->_datasource_type) { |
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case 'rpc': |
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// get rpc connection information from global constants |
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$metadata = array( |
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//package => 'Data::Driver::Proxy', |
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//package => 'DataSource::Proxy::XMLRPC', |
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//package => 'DataSource::Generic', |
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//package => 'DesignPattern::RemoteProxy', |
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Host => RPC_HOSTNAME, |
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Port => RPC_PORT, |
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); |
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$good = 1; |
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break; |
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} |
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|
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if ($good) { |
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|
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// V1: |
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/* |
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$this->_out = array( |
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datasource_type => $datasource, |
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adapter_type => 'Data', |
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metadata => $metadata, |
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); |
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*/ |
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|
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// V2: |
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//$this->_out = $metadata; |
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|
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// V3: |
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$this->merge_to($this->_metadata, $metadata); |
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|
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} |
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|
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// trace |
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//print Dumper($this); |
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|
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} |
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|
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function check() { |
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if (!sizeof($this->_metadata)) { |
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user_error("DataSource::Locator::check() failed: " . "Locator metadata not established, please check configuration options."); |
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return; |
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} |
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return 1; |
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} |
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|
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|
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} |
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|
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?> |