| 1 |
<?php |
| 2 |
|
| 3 |
/** |
| 4 |
* This file contains the ProxyDataSource child class |
| 5 |
* that uses the Data::Driver::Proxy object to talk to a remote rpc server. |
| 6 |
* |
| 7 |
* Data::Driver::Proxy uses a PEAR XML::RPC object to actually |
| 8 |
* talk HTTP and serialize data chunks to and from XML, |
| 9 |
* but adds some caching to this "process of fetching data from a remote side". |
| 10 |
* It "proxies" arbitrary data chunks a) inside a native php4 session, |
| 11 |
* b) by talking to a rdbms (single proxy-table) or c) [TODO] using PEAR::Cache. |
| 12 |
* |
| 13 |
* @author Andreas Motl <andreas.motl@ilo.de> |
| 14 |
* @author Sebastian Utz <seut@tunemedia.de> |
| 15 |
* @package phpHtmlLib |
| 16 |
*/ |
| 17 |
|
| 18 |
/** |
| 19 |
* $Id$ |
| 20 |
* |
| 21 |
* $Log$ |
| 22 |
* |
| 23 |
*/ |
| 24 |
|
| 25 |
/** |
| 26 |
* This requires the MemoryDataSource base class |
| 27 |
* |
| 28 |
*/ |
| 29 |
include_once($phphtmllib."/widgets/data_source/MemoryDataSource.inc"); |
| 30 |
|
| 31 |
/** |
| 32 |
* Have to have PEAR and DB included |
| 33 |
* the pear dir must be in the |
| 34 |
* include path. |
| 35 |
*/ |
| 36 |
//require_once("PEAR.php"); // FIXME: what about PEAR::XML::RPC? |
| 37 |
//require_once("DB.php"); |
| 38 |
|
| 39 |
/** |
| 40 |
* This ProxyDataSource child class is *completely* independent |
| 41 |
* of a specific storage implementation and intended to be a wrapper |
| 42 |
* class on the way from phpHtmlLib to Xyz. |
| 43 |
* ("Yyz" gets represented by Data::Storage by now.....) |
| 44 |
* |
| 45 |
* ProxyDataSource interacts with an intermediate "proxy" object |
| 46 |
* (e.g. Data::Driver::Proxy) when doing queries. |
| 47 |
* Don't mix this up with a persistent database handle which gets |
| 48 |
* reused each and every time for different queries. |
| 49 |
* Here *is* a new instance of Data::Driver::Proxy for *each* query. |
| 50 |
* |
| 51 |
* But the point is: Caching! The actual *data* isn't read redundant! |
| 52 |
* |
| 53 |
* Data::Driver::Proxy instantiates "handlers" below itself |
| 54 |
* which act as encapsulated workers to actually do the stuff to do. |
| 55 |
* It can cache data for "disconnected mode" using the |
| 56 |
* php PEAR DB abstraction objects. |
| 57 |
* One worker already implemented is Data::Driver::RPC::Remote, which |
| 58 |
* talks to a RPC::XML server (todo: talk SOAP!) using PEAR::XML::RPC. |
| 59 |
* |
| 60 |
* How to use? |
| 61 |
* |
| 62 |
* Pass an array holding "locator metadata" to the constructor. |
| 63 |
* ProxyDataSource takes care of the rest. |
| 64 |
* |
| 65 |
* Pass an array to the constructor: (e.g.) |
| 66 |
* |
| 67 |
* 1. doing rpc-calls.... |
| 68 |
* $locator = array( |
| 69 |
* type => 'rpc', |
| 70 |
* metadata => array( Host => 'localhost', Port => '8765' ), |
| 71 |
* ); |
| 72 |
* $source = new ProxyDataSource($locator); |
| 73 |
* $this->set_data_source( &$source ); |
| 74 |
* |
| 75 |
* 2. [proposal] common datahandles.... |
| 76 |
* $locator = array( |
| 77 |
* type => 'mysql', |
| 78 |
* dsn => 'known dsn markup', |
| 79 |
* ); |
| 80 |
* $source = new ProxyDataSource($locator); |
| 81 |
* $this->set_data_source( &$source ); |
| 82 |
* |
| 83 |
* @author Andreas Motl <andreas.motl@ilo.de> |
| 84 |
* @author Sebastian Utz <seut@tunemedia.de> |
| 85 |
* @package phpHtmlLib |
| 86 |
*/ |
| 87 |
|
| 88 |
/** |
| 89 |
* Todo: |
| 90 |
* |
| 91 |
* o mungle this to be able to be wrapped around phpHtmlLib's own storage-handles |
| 92 |
* o implement another Data::Driver::Proxy container |
| 93 |
* |
| 94 |
*/ |
| 95 |
|
| 96 |
class ProxyDataSource extends MemoryDataSource { |
| 97 |
|
| 98 |
/** |
| 99 |
* This var holds the locator metadata hash |
| 100 |
* that is used to feed metadata to a per-query-instance |
| 101 |
* of a Data::Driver::Proxy object. |
| 102 |
*/ |
| 103 |
var $_locator = NULL; |
| 104 |
|
| 105 |
/** |
| 106 |
* This var holds the query hash |
| 107 |
* that is used to feed as query to a per-query-instance |
| 108 |
* of a Data::Driver::Proxy object. |
| 109 |
*/ |
| 110 |
var $_query = NULL; |
| 111 |
|
| 112 |
|
| 113 |
/** |
| 114 |
* This var holds the Proxy object |
| 115 |
* that is used to do the work. |
| 116 |
* It acts as a dispatcher combining result caching. |
| 117 |
* It is assumed that this provides 4 methods: |
| 118 |
* queryData() - execute a query against a data storage |
| 119 |
* querySchema() - execute a query against underlying storage metadata |
| 120 |
* sendCommand() - send a command against an arbitrary execution engine |
| 121 |
*/ |
| 122 |
var $_proxy = NULL; |
| 123 |
|
| 124 |
/** |
| 125 |
* this holds the query result from the |
| 126 |
* Data::Driver::Proxy->queryXyz() call |
| 127 |
* |
| 128 |
*/ |
| 129 |
var $_result = NULL; |
| 130 |
|
| 131 |
|
| 132 |
/** |
| 133 |
* The constructor is used to pass in the |
| 134 |
* locator metadata hash. |
| 135 |
* |
| 136 |
* @param LocatorMetadataHash array - layout: array( type => '', metadata => '', dsn => '' ) |
| 137 |
* @param Query array - layout: array( type => '', metadata => '', dsn => '' ) |
| 138 |
*/ |
| 139 |
function ProxyDataSource( &$locator, $query ) { |
| 140 |
$this->set_locator( $locator ); |
| 141 |
$this->set_query( $query ); |
| 142 |
} |
| 143 |
|
| 144 |
/** |
| 145 |
* Set the locator metadata hash we will feed *partly* |
| 146 |
* to an encapsulated Data::Driver::Proxy instance. |
| 147 |
* |
| 148 |
* @param LocatorMetadataHash array - |
| 149 |
* |
| 150 |
*/ |
| 151 |
function set_locator( &$locator ) { |
| 152 |
$this->_locator = &$locator; |
| 153 |
} |
| 154 |
|
| 155 |
/** |
| 156 |
* Set the query metadata hash we will feed *completely* |
| 157 |
* to an encapsulated Data::Driver::Proxy instance. |
| 158 |
* |
| 159 |
* @param QueryDeclaration array - |
| 160 |
* |
| 161 |
*/ |
| 162 |
function set_query( $query ) { |
| 163 |
$this->_query = $query; |
| 164 |
} |
| 165 |
|
| 166 |
/** |
| 167 |
* Directly inject a Data::Driver::Proxy instance to use. |
| 168 |
* |
| 169 |
* @param Data::Driver::Proxy object - &$proxy |
| 170 |
* |
| 171 |
*/ |
| 172 |
function set_proxy( &$proxy ) { |
| 173 |
$this->_proxy = &$proxy; |
| 174 |
} |
| 175 |
|
| 176 |
/** |
| 177 |
* Issue remote/proxy call |
| 178 |
* Stolen from Application_AbstractBackend::_remote_method (RefactoringProposal?) |
| 179 |
* Tweaked a bit: proxy package now taken from $this->_proxy_name |
| 180 |
* |
| 181 |
* Create a new instance of a proxy and store it for later reuse. |
| 182 |
* Read the locator metadata hash and create |
| 183 |
* the proxy handler instance using passed-in name. |
| 184 |
* |
| 185 |
* @param string - $proxy_name (namespaced classname - perl syntax - e.g.: Data::Driver::Proxy) |
| 186 |
* |
| 187 |
*/ |
| 188 |
function call_proxy_method() { |
| 189 |
|
| 190 |
|
| 191 |
// 1. read args |
| 192 |
|
| 193 |
$arg_list = func_get_args(); |
| 194 |
$command = array_shift($arg_list); |
| 195 |
$cache_key = join("-", array(session_id(), $command, join('_', $arg_list) )); |
| 196 |
//print "cache_key: $cache_key<br>"; |
| 197 |
|
| 198 |
// FIXME: what if arg_list still contains more elements after doing this? |
| 199 |
$query = array_shift($arg_list); |
| 200 |
|
| 201 |
|
| 202 |
// 2. prepare proxy-options |
| 203 |
|
| 204 |
// read from locator metadata |
| 205 |
$proxy_name = $this->_locator[metadata][package]; |
| 206 |
$rpcinfo = array( Host => $this->_locator[metadata][Host], Port => $this->_locator[metadata][Port] ); |
| 207 |
|
| 208 |
// FIXME! implement this into Data::Driver::RPC::Remote! |
| 209 |
//$rpcinfo[to_latin] = 1; |
| 210 |
|
| 211 |
// FIXME! patch query |
| 212 |
if (sizeof($query) == 1) { |
| 213 |
$query = $query[0]; |
| 214 |
} |
| 215 |
|
| 216 |
// -------------------- clone this & modify ---------- |
| 217 |
$proxy = mkObject($proxy_name, $cache_key, array( key => 1, command => $command, query => $query, remote => 1, rpcinfo => $rpcinfo, cache => array( db => 0, session => 1 ) ) ); |
| 218 |
$this->set_proxy( $proxy ); |
| 219 |
//$result = $resultHandle->getAttributes(); |
| 220 |
//return $result; |
| 221 |
//$this->_result = $resultHandle->getAttributes(); |
| 222 |
//$this->_result = $this->_proxy->getAttributes(); |
| 223 |
// -------------------- clone this & modify ---------- |
| 224 |
|
| 225 |
} |
| 226 |
|
| 227 |
function O_do_query() { |
| 228 |
$this->_result = $this->_db->query($this->_query); |
| 229 |
if (DB::isError($this->_result)) { |
| 230 |
$msg = $this->_result->getMessage(); |
| 231 |
user_error("PEARSQLDataListSource::do_query() - query failed : ".$msg); |
| 232 |
} |
| 233 |
} |
| 234 |
|
| 235 |
function call_proxy() { |
| 236 |
|
| 237 |
// make up a command from metadata |
| 238 |
// FIXME: abstract this some more (e.g. via a CommandMapper|Registry) |
| 239 |
switch ($this->_query[metatype]) { |
| 240 |
case 'data': |
| 241 |
//$command = 'queryData'; |
| 242 |
$command = 'getObjects'; // FIXME!!! |
| 243 |
$args = array(); |
| 244 |
switch ($this->_query[vartype]) { |
| 245 |
case 'object': |
| 246 |
if (!$this->_query[classname]) { |
| 247 |
$msg = "_query[vartype] == 'object' requires _query[classname]"; |
| 248 |
user_error("ProxyDataSource::do_query() - failed: " . $msg); |
| 249 |
} |
| 250 |
array_push($args, $this->_query[classname]); |
| 251 |
break; |
| 252 |
} |
| 253 |
break; |
| 254 |
case 'schema': |
| 255 |
$command = 'querySchema'; |
| 256 |
break; |
| 257 |
} |
| 258 |
|
| 259 |
// trace |
| 260 |
if ($this->trace) { |
| 261 |
print "ProxyDataSource->do_query()<br/>"; |
| 262 |
print "_locator = " . Dumper($this->_locator); |
| 263 |
print "_query = " . Dumper($this->_query); |
| 264 |
print "<b>\$command = " . $command . "</b><br/>"; |
| 265 |
print "<b>\$args = " . Dumper($args) . "</b><br/>"; |
| 266 |
} |
| 267 |
|
| 268 |
// pre-flight checks |
| 269 |
if (!$command) { |
| 270 |
$msg = "Remote command could not be resolved, please pass in or check configuration."; |
| 271 |
user_error("ProxyDataSource::do_query() - failed: " . $msg); |
| 272 |
return; |
| 273 |
} |
| 274 |
|
| 275 |
// do remote call here and get result |
| 276 |
// FIXME: handle synchronous/asynchronous mode here!!! |
| 277 |
$this->call_proxy_method($command, $args); |
| 278 |
// TODO: ... = $this->poll_proxy_result and $this->get_proxy_result |
| 279 |
$this->_result = $this->_proxy->getAttributes(); |
| 280 |
|
| 281 |
// trace |
| 282 |
//print "_result = " . Dumper($this->_result); |
| 283 |
print "_result - count = " . sizeof($this->_result) . "<br/>"; |
| 284 |
|
| 285 |
// pass data to MemoryDataSource |
| 286 |
|
| 287 |
// V1 - doesn't work! |
| 288 |
//$this->_data_list = $this->_result; |
| 289 |
|
| 290 |
// V2 - ??? |
| 291 |
//$this->MemoryDataSource(); |
| 292 |
|
| 293 |
// V3 - copy & paste |
| 294 |
/* |
| 295 |
foreach ($this->_result as $value) { |
| 296 |
print Dumper($value); |
| 297 |
if ($this->add_data_row($value)) { |
| 298 |
$count++; |
| 299 |
} |
| 300 |
} |
| 301 |
$this->set_total_rows( $count ); |
| 302 |
$this->sort(); |
| 303 |
*/ |
| 304 |
|
| 305 |
} |
| 306 |
|
| 307 |
|
| 308 |
|
| 309 |
function O_do_prequery() { |
| 310 |
//print "prequery!<br/>"; |
| 311 |
// HACK!!! |
| 312 |
// modify behaviour here: for now it is needed to call for the schem |
| 313 |
// eventually modify here to get schema from some registry component (already locally available) |
| 314 |
$this->call_proxy(); |
| 315 |
//print Dumper($this->_result); |
| 316 |
//print Dumper($this->_result[0]); |
| 317 |
//exit; |
| 318 |
|
| 319 |
//$this->_get_header(); |
| 320 |
} |
| 321 |
|
| 322 |
function do_query() { |
| 323 |
//print "query!<br/>"; |
| 324 |
$this->handle_result(); |
| 325 |
} |
| 326 |
|
| 327 |
function _get_header() { |
| 328 |
//$this->do_prequery(); |
| 329 |
// FIXME: prevent multi-calls by base class |
| 330 |
$this->call_proxy(); |
| 331 |
foreach($this->_result[0] as $key => $value) { |
| 332 |
array_push($this->_data_keys, $key); |
| 333 |
} |
| 334 |
|
| 335 |
$this->set_schema($this->_result[0]); |
| 336 |
|
| 337 |
//$this->_get_header(); |
| 338 |
//return $this->_data_keys; |
| 339 |
|
| 340 |
} |
| 341 |
|
| 342 |
|
| 343 |
/** |
| 344 |
* This function gets the next data row |
| 345 |
* from the query() |
| 346 |
* |
| 347 |
* @return array() |
| 348 |
*/ |
| 349 |
function O_get_next_data_row() { |
| 350 |
return $this->_result->fetchRow(DB_FETCHMODE_ASSOC); |
| 351 |
} |
| 352 |
|
| 353 |
/** |
| 354 |
* This function builds the limit |
| 355 |
* clause portion of a DB query. |
| 356 |
* |
| 357 |
* @return string - the limit portion of |
| 358 |
* the query. |
| 359 |
*/ |
| 360 |
function O_build_limit_clause($offset, $limit) { |
| 361 |
if ($this->get_limit() != -1 ) { |
| 362 |
if ($offset == '' || $offset == "none") { |
| 363 |
$offset = 0; |
| 364 |
} |
| 365 |
switch(get_class($this->_db)) { |
| 366 |
case "db_mysql": |
| 367 |
$clause = " LIMIT $offset, $limit "; |
| 368 |
break; |
| 369 |
case "db_pgsql": |
| 370 |
$clause = " LIMIT $limit, $offset "; |
| 371 |
break; |
| 372 |
default: |
| 373 |
$clause = " LIMIT $offset, $limit "; |
| 374 |
break; |
| 375 |
} |
| 376 |
return $clause; |
| 377 |
} else { |
| 378 |
return NULL; |
| 379 |
} |
| 380 |
} |
| 381 |
|
| 382 |
/** |
| 383 |
* find the number of rows to be returned |
| 384 |
* from a query from a table and where clause |
| 385 |
* |
| 386 |
* @param string $table - the table to count from |
| 387 |
* @param string $where_clause - a where clause |
| 388 |
* |
| 389 |
* @return int the # of rows |
| 390 |
*/ |
| 391 |
function O_count($tables, $where_clause='', $count_clause='*') { |
| 392 |
$query = "select count(".$count_clause.") as COUNT from ".$tables." ".$where_clause; |
| 393 |
$result = $this->_db->query($query); |
| 394 |
if (DB::isError($this->_result)) { |
| 395 |
$msg = $result->getMessage(); |
| 396 |
user_error("PEARSQLDataListSource::count() - query failed : ".$msg); |
| 397 |
} |
| 398 |
$value = $result->fetchRow(DB_FETCHMODE_ASSOC); |
| 399 |
return ($value ? (int)$value["COUNT"] : NULL); |
| 400 |
} |
| 401 |
|
| 402 |
} |
| 403 |
|
| 404 |
?> |
Parent Directory
| 
Revision Log
