Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
| 1 | <?php  | 
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| 7 | class LDAPMemberExtension extends DataExtension  | 
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| 8 | { | 
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| 9 | /**  | 
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| 10 | * @var array  | 
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| 11 | */  | 
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| 12 | private static $db = [  | 
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| 13 | // Unique user identifier, same field is used by SAMLMemberExtension  | 
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| 14 | 'GUID' => 'Varchar(50)',  | 
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| 15 | 'Username' => 'Varchar(64)',  | 
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| 16 | 'IsExpired' => 'Boolean',  | 
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| 17 | 'LastSynced' => 'SS_Datetime',  | 
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| 18 | ];  | 
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| 19 | |||
| 20 | /**  | 
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| 21 |      * These fields are used by {@link LDAPMemberSync} to map specific AD attributes | 
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| 22 |      * to {@link Member} fields. | 
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| 23 | *  | 
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| 24 | * @var array  | 
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| 25 | * @config  | 
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| 26 | */  | 
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| 27 | private static $ldap_field_mappings = [  | 
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| 28 | 'givenname' => 'FirstName',  | 
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| 29 | 'samaccountname' => 'Username',  | 
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| 30 | 'sn' => 'Surname',  | 
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| 31 | 'mail' => 'Email',  | 
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| 32 | ];  | 
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| 33 | |||
| 34 | /**  | 
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| 35 | * The location (relative to /assets) where to save thumbnailphoto data.  | 
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| 36 | *  | 
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| 37 | * @var string  | 
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| 38 | * @config  | 
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| 39 | */  | 
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| 40 | private static $ldap_thumbnail_path = 'Uploads';  | 
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| 41 | |||
| 42 | /**  | 
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| 43 | * When enabled, LDAP managed Member records (GUID flag)  | 
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| 44 | * have their data written back to LDAP on write.  | 
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| 45 | *  | 
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| 46 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 47 | * credentials, which is why this is disabled by default.  | 
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| 48 | *  | 
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| 49 | * @var bool  | 
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| 50 | * @config  | 
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| 51 | */  | 
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| 52 | private static $update_ldap_from_local = false;  | 
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| 53 | |||
| 54 | /**  | 
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| 55 | * If enabled, Member records with a Username field have the user created in LDAP  | 
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| 56 | * on write.  | 
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| 57 | *  | 
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| 58 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 59 | * credentials, which is why this is disabled by default.  | 
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| 60 | *  | 
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| 61 | * @var bool  | 
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| 62 | * @config  | 
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| 63 | */  | 
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| 64 | private static $create_users_in_ldap = false;  | 
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| 65 | |||
| 66 | /**  | 
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| 67 | * If enabled, deleting Member records mapped to LDAP deletes the LDAP user.  | 
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| 68 | *  | 
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| 69 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 70 | * credentials, which is why this is disabled by default.  | 
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| 71 | *  | 
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| 72 | * @var bool  | 
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| 73 | * @config  | 
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| 74 | */  | 
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| 75 | private static $delete_users_in_ldap = false;  | 
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| 76 | |||
| 77 | /**  | 
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| 78 | * @param FieldList $fields  | 
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| 79 | */  | 
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| 80 | public function updateCMSFields(FieldList $fields)  | 
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| 130 | |||
| 131 | public function validate(ValidationResult $validationResult)  | 
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| 132 |     { | 
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| 133 | // We allow empty Username for registration purposes, as we need to  | 
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| 134 | // create Member records with empty Username temporarily. Forms should explicitly  | 
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| 135 | // check for Username not being empty if they require it not to be.  | 
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| 136 |         if (!$this->owner->config()->create_users_in_ldap) { | 
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| 137 | return;  | 
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| 138 | }  | 
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| 139 | |||
| 140 |         if (!preg_match('/^[a-z0-9\.]+$/', $this->owner->Username)) { | 
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| 141 | $validationResult->error(  | 
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| 142 | 'Username must only contain lowercase alphanumeric characters and dots.',  | 
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| 143 | 'bad'  | 
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| 144 | );  | 
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| 145 | throw new ValidationException($validationResult);  | 
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| 146 | }  | 
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| 147 | }  | 
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| 148 | |||
| 149 | /**  | 
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| 150 | * Generate a username for the user based on their name and/or email  | 
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| 151 | * @return string  | 
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| 152 | */  | 
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| 153 | public function generateLDAPUsername()  | 
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| 186 | |||
| 187 | /**  | 
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| 188 | * Create the user in LDAP, provided this configuration is enabled  | 
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| 189 | * and a username was passed to a new Member record.  | 
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| 190 | */  | 
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| 191 | public function onBeforeWrite()  | 
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| 209 | |||
| 210 | /**  | 
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| 211 | * Update the local data with LDAP, and ensure local membership is also set in  | 
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| 212 | * LDAP too. This writes into LDAP, provided that feature is enabled.  | 
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| 213 | */  | 
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| 214 | View Code Duplication | public function onAfterWrite()  | 
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| 228 | |||
| 229 | View Code Duplication |     public function onAfterDelete() { | 
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| 241 | |||
| 242 | /**  | 
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| 243 |      * Triggered by {@link Member::logIn()} when successfully logged in, | 
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| 244 | * this will update the Member record from AD data.  | 
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| 245 | */  | 
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| 246 | public function memberLoggedIn()  | 
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| 252 | }  | 
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| 253 | 
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.