git.m6w6.name Git - m6w6/pq-gateway/blob - lib/pq/Gateway/Table/Relations.php

   1 <?php
   2
   3 namespace pq\Gateway\Table;
   4
   5 use \pq\Gateway\Table;
   6
   7 const RELATION_SQL = <<<SQL
   8 select
   9          cl1.relname  as "foreignTable"
  10         ,array(
  11                 select
  12                          attname
  13                         from pg_attribute,
  14                         generate_subscripts(conkey,1) index
  15                 where
  16                         attrelid = cl1.oid
  17                 and attnum   = any(conkey)
  18                 and conkey[index] = attnum
  19                 order by
  20                          index
  21         )             as "foreignColumns"
  22         ,cl2.relname  as "referencedTable"
  23         ,array(
  24                 select
  25                          attname
  26                         from pg_attribute,
  27                         generate_subscripts(confkey,1) index
  28                 where
  29                         attrelid = cl2.oid
  30                 and attnum   = any(confkey)
  31                 and confkey[index] = attnum
  32                 order by
  33                          index
  34         )             as "referencedColumns"
  35 from pg_constraint co
  36 join pg_class      cl1 on cl1.oid = co.conrelid
  37 join pg_class      cl2 on cl2.oid = co.confrelid
  38 where
  39          cl1.relname  = \$1
  40 and co.contype    = 'f'
  41 and co.confrelid != 0
  42 SQL;
  43
  44 /**
  45  * Foreign key list
  46  */
  47 class Relations implements \Countable, \IteratorAggregate
  48 {
  49         /**
  50          * @var array
  51          */
  52         protected $references;
  53
  54         /**
  55          * @param \pq\Gateway\Table $table
  56          */
  57         function __construct(Table $table) {
  58                 $cache = $table->getMetadataCache();
  59                 if (!($this->references = $cache->get("$table:relations"))) {
  60                         $table->getQueryExecutor()->execute(
  61                                 new \pq\Query\Writer(RELATION_SQL, array($table->getName())),
  62                                 function($result) use($table, $cache) {
  63                                         $rel = $result->map([1,2], null, \pq\Result::FETCH_ASSOC);
  64                                         foreach ($rel as $ref) {
  65                                                 foreach ($ref as $table => $key) {
  66                                                         $reference = new Reference($key);
  67                                                         $this->references[$table][$reference->name] = $reference;
  68                                                 }
  69                                         }
  70                                         $cache->set("$table:relations", $this->references);
  71                                 }
  72                         );
  73                 }
  74         }
  75
  76         function __isset($r) {
  77                 return isset($this->references[$r]);
  78         }
  79
  80         function __get($r) {
  81                 return $this->references[$r];
  82         }
  83
  84         function __set($r, $v) {
  85                 $this->references[$r] = $v;
  86         }
  87
  88         function __unset($r){
  89                 unset($this->references[$r]);
  90         }
  91
  92         /**
  93          * Get a reference to a table
  94          * @param string $table
  95          * @param string $ref
  96          * @return \pq\Gateway\Table\Reference
  97          */
  98         function getReference($table, $ref = null) {
  99                 if (isset($this->references[$table])) {
 100                         if (!strlen($ref)) {
 101                                 return current($this->references[$table]);
 102                         }
 103                         if (isset($this->references[$table][$ref])) {
 104                                 return $this->references[$table][$ref];
 105                         }
 106                 }
 107         }
 108
 109         /**
 110          * Implements \Countable
 111          * @return int
 112          */
 113         function count() {
 114                 return array_sum(array_map("count", $this->references));
 115         }
 116
 117         /**
 118          * Implements \IteratorAggregate
 119          * @return \ArrayIterator
 120          */
 121         function getIterator() {
 122                 return new \ArrayIterator($this->references);
 123         }
 124 }