Caffeine Web Framework

1<?php
2abstract class Record{
3    protected $db; //PDO database handle
4    public $table; //name of the table, usually same as the class name
5    public $keyField = 'id'; //name of the primary key column
6    public $id; //primary key value, regardless of name
7    protected $attrs = array(); //table rows
8    protected $info = NULL; //contains serialized data of virtual rows
9    protected $errors = array(); //validation errors, which will stop creates/updates
10    
11    function __construct(){
12        $this->table = strtolower(get_class($this));
13        $this->db = Database::getMain();
14    }
15    
In effect this method (along with set, isset, etc.) creates dynamic fields to represent database columns. Names of those fields are taken from keyField property, attrs property and info property if it's defined. On create or update, all the fields from the "info" array are serialized and put into the single "info" column in the database. (2008.01.03 10:42)[update][delete]
16    function __set($name, $value){
17        if ($name == $this->keyField) {
18            $this->id = $value;
19        } elseif (key_exists($name, $this->attrs)) {
20            $this->attrs[$name] = $value;
21        } elseif (isset($this->info) && key_exists($name, $this->info)) {
22            $this->info[$name] = $value;
23        } else {
24            trigger_error("Setting new '$name' attribute", E_USER_NOTICE);
25            $this->$name = $value;
26        }
27    }
28    
29    function __get($name){
30        if ($name == $this->keyField) {
31            return $this->id;
32        } elseif (key_exists($name, $this->attrs)) {
33            return $this->attrs[$name];
34        } elseif (isset($this->info) && key_exists($name, $this->info)) {
35            return $this->info[$name];
36        } else {
37            trigger_error("Can't get '$name' attribute", E_USER_NOTICE);
38        }
39    }
40    
41    function __isset($name){
42        if ($name == $this->keyField) {
43            return isset($this->id);
44        } elseif (key_exists($name, $this->attrs)) {
45            return isset($this->attrs[$name]);
46        } elseif (isset($this->info) && key_exists($name, $this->info)) {
47            return isset($this->info[$name]);
48        } else {
49            return FALSE;
50        }
51    }
52    
53    function __call($name, $attrs){
54        if (substr($name, 0, 6) == 'loadBy') {
55            $field = strtolower($name[6]).substr($name, 7);
56            return $this->loadBy($field, $attrs[0]);
57        } elseif (substr($name, 0, 8) == 'selectBy') {
58            $field = strtolower($name[8]).substr($name, 9);
59            return $this->selectBy($field, $attrs[0], @$attrs[1], @$attrs[2]);
60        } elseif (substr($name, 0, 7) == 'countBy') {
61            $field = strtolower($name[7]).substr($name, 8);
62            return $this->countBy($field, @$attrs[0]);
63        } else {
64            trigger_error("Method '$name' is not defined", E_USER_ERROR);
65        }
66    }
67    
68    private function loadBy($field, $value){
69        if (!array_key_exists($field, $this->attrs)) {
70            throw new Exception('Trying to load by invalid field');
71        }
72        return $this->loadWith("* FROM $this->table WHERE $field = ?", array($value));
73    }
74    
Returns object that represent all the records that have the specified column set to the specified value. (2008.12.14 04:07)[update][delete]
75    private function selectBy($field, $value, $pageSize = 0, $page = 0){
76        if (!array_key_exists($field, $this->attrs)) {
77            throw new Exception("Trying to select by invalid field '$field'");
78        }
79        return $this->selectWith("* FROM $this->table WHERE $field = ?", array($value), $pageSize, $page);
80    }
81    
82    private function countBy($field, $values = NULL){
83        if ($values == array()) {
84            return array();
85        }
86        $list = '('.implode(',', array_pad(array(), sizeof($values), '?')).')';
87        $query = "SELECT $field, COUNT(*) as count FROM $this->table";
88        if ($values != NULL) {
89            $query .= " WHERE $field IN $list";
90        }
91        $query .= " GROUP BY $field";    
92        $statement = $this->db->prepare($query);
93        $statement->execute(array_values($values));
94        
95        $countMap = array();
96        foreach ($statement->fetchAll(PDO::FETCH_ASSOC) as $row) {
97            $countMap[$row[$field]] = $row['count'];
98        }
99        return $countMap;
100    }
101    
102    function setAttrs($attrs){ //convenience function to input HTML form data
103        foreach ($attrs as $name => $value) {
104            if (key_exists($name, $this->attrs)) {
105                $this->$name = $value;
106            } elseif (isset($this->info)&& key_exists($name, $this->info)) {
107                $this->info[$name] = $value;
108            } else {
109                trigger_error("Can't set '$name' attribute", E_USER_NOTICE);
110            }
111        }
112    }
113    
This function generated an array of fields that will represent this object in the database.  (2008.12.14 03:42)[update][delete]
114    protected function getDbAttrs(){ //converts the object to a hash that matches DB fields
115        $attrs = array();
116        if (isset($this->info)) {
117            $attrs['info'] = Ori::fold($this->info, Ori::NO_NULLS | Ori::UNBRACE);
118        }
119        foreach ($this->attrs as $name => $value) {
120            $methodName = 'get'.$name.'ForDb';
121            if (method_exists($this, $methodName)) {
122                $attrs[$name] = $this->$methodName();
123            } else {
124                $attrs[$name] = $value;
125            }
126        }
127        $attrs[$this->keyField] = $this->id;
128        return $attrs;
129    }
130    
This method takes an array of fields from a database and populate the current object with the given data. (2008.12.14 03:43)[update][delete]
131    protected function setDbAttrs($attrs){ //Inverse of getDbAttrs
132        if (isset($this->info) && isset($attrs['info'])) {
133            foreach ((array) Ori::unfold($attrs['info'], Ori::BRACE) as $key => $value) {
134                $this->info[$key] = $value;
135            }
136            unset($attrs['info']);
137        }
138        foreach ($attrs as $name => $value) {
139            $methodName = 'set'.$name.'FromDb';
140            if (method_exists($this, $methodName)) {
141                $this->$methodName($value);
142            } else {
143                $this->$name = $value;
144            }
145        }
146    }
147    
148    protected function check(){ //validation method, called before writing to DB
149    }
150    
151    function create(){
152        $this->check();
153        if (!empty($this->errors)) {
154            throw new Exception(join("\n", $this->errors));
155        }
156        
157        $attrs = $this->getDbAttrs();
158        $names = array();
159        $values = array();
160        foreach ($attrs as $name => $value) {
161            $names[] = $name;
162            $values[] = ':'.$name;
163        }
164        $names = join(', ', $names);
165        $values = join(', ', $values);
166        $query = "INSERT INTO $this->table ($names) VALUES ($values)";
167        $statement = $this->db->prepare($query);
168        $statement->execute($attrs);
169        $id = $this->db->lastInsertId();
170        if (!empty($id)) { $this->id = $id; }
171    }
172    
Updates the DB record corresponding to this object. You need to set id field or, better yet, load() an appropriate record so that the object knows what to update. (2008.12.14 03:57)[update][delete]
173    function update(){
174        $this->check();
175        if (!empty($this->errors)) {
176            throw new Exception(join("\n", $this->errors));
177        }
178        
179        $attrs = $this->getDbAttrs();
180        $pairs = array();
181        $args = array();
182        foreach ($attrs as $name => $value) {
183            $pairs[] = "$name = ?";
184            $args[] = $value;
185        }
186        $pairs = join(', ', $pairs);
187        $query = "UPDATE $this->table SET $pairs WHERE $this->keyField = ?";
188        $args[] = $this->id;
189        $statement = $this->db->prepare($query);
190        $statement->execute($args);
191    }
192
193    function load($id){
194        return $this->loadWith("* FROM $this->table WHERE $this->keyField=?", array($id));
195    }
196    
197    function loadWith($query, $params = array()){
198        $statement = $this->db->prepare('SELECT '.$query);
199        $statement->execute($params);
200        $attrs = $statement->fetch(PDO::FETCH_ASSOC);
201        if ($attrs == NULL) {
202            throw new Exception(get_class($this)." did not load");
203        }
204        $this->setDbAttrs($attrs);
205    }
206    
207    function selectWith($query, $params = array(), $pageSize = 0, $pageNum = 0){
208        $pageSize = (int) $pageSize;
209        if ($pageSize > 0) {
210            $offset = $pageNum * $pageSize;
211            $query .= " LIMIT $pageSize";
212            if ($offset > 0) {
213                $query .= " OFFSET $offset";
214            }
215        }
216        $statement = $this->db->prepare('SELECT '.$query);
217        $statement->execute($params);
218        $self = get_class($this);
219        $objects = array();
220        while ($attrs = $statement->fetch(PDO::FETCH_ASSOC)) {
221            $object = new $self();
222            $object->setDbAttrs($attrs);
223            $objects[] = $object;
224        }
225        return $objects;
226    }
227    
Returns an array with all objects corresponding to this class. (Pagination applies, so this might be just a page of those records.) (2008.12.14 03:50)[update][delete]
228    function selectAll($pageSize = 0, $pageNum = 0){
229        return $this->selectWith("* FROM $this->table", NULL, $pageSize, $pageNum);
230    }
231    
232    function delete($id){
233        return $this->deleteWhere("$this->keyField = ?", array($id));;
234    }
235    
236    function deleteWhere($where, $params = array()){
237        $query = "DELETE FROM $this->table WHERE $where";
238        $statement = $this->db->prepare($query);
239        $statement->execute($params);
240        return $statement->rowCount();
241    }
242    
243    function count($where = NULL, $params = array()){
244        $query = "SELECT COUNT(*) FROM $this->table";
245        if (!empty($where)) {
246            $query .= " WHERE ".$where;
247        }
248        $statement = $this->db->prepare($query);
249        $statement->execute($params);
250        $row = $statement->fetch(PDO::FETCH_NUM);
251        return $row[0];
252    }
253    
254    function exists($id){
255        return $this->count("$this->keyField = ?", array($id));
256    }
257    
258    //in: array(2, 5, 7) => out: array(objectWithId2, objectWithId5, objectWithId7)
259    function resolve($mappedIds){
260        if (empty($mappedIds)) {
261            return array();
262        }
263        $list = '('.implode(',', array_pad(array(), sizeof($mappedIds), '?')).')';
264        $objects = $this->selectWith("* FROM $this->table 
265            WHERE $this->keyField IN $list", array_values($mappedIds));
266        $objectMap = array();
267        foreach ($objects as $object) {
268            $objectMap[$object->id] = $object;
269        }
270        return $objectMap;
271    }
272}