TypoScript Syntax

1.4.3. Implementing Conditions

Now we know how to parse TypoScript and the only thing we need is to implement support for conditions. As stated a few places the evaluation of a condition is external to TypoScript and all you need to do in order to have an external process deal with conditions is to pass an object as the second parameter to the parse-function. This is done in the code listing below:

 

     1: require_once(PATH_t3lib.'class.t3lib_tsparser.php');

     2: 

     3: class myConditions {

     4:     function match($conditionLine)    {

     5:         if ($conditionLine == '[TYPO3 IS GREAT]')    return true; 

     6:     }

     7: }

     8: $matchObj = t3lib_div::makeInstance('myConditions');

     9: 

    10: $TSparserObject = t3lib_div::makeInstance('t3lib_tsparser');

    11: $TSparserObject->parse($tsString, $matchObj);

    12: 

    13: debug($TSparserObject->setup);

Here goes some notes to this listing:

1. Line 3-8 defines a very simple class with a function, match(), inside.
   The function "match()" must exist and take a string as its argument and the match function must also return a boolean value. This function should be programmed to evaluate the condition line according to your specifications.
   Currently, if a condition line contains the value "[TYPO3 IS GREAT]" then the condition will evaluate to true and parse the subsequent TypoScript.

2. Line 11: Here the instantiated object, $matchObj, of the "myConditions" class is passed to the parser.

3. Line 13: Just a little side note: Instead of using PHPs "print_r" function we use the classic debug() function in TYPO3 which prints an array in an HTML table - some of us think this is the nicest way to look into the content of an array (make your own opinion from the screenshot below).

 

Anyways, let's test the custom condition class from the code listing above. This is done by parsing this TypoScript code:

 

     0: someOtherTS = 123

     1:

     2: [TYPO3 IS GREAT]

     3:

     4: message = Yes

     5: someOtherTS = 987

     6:

     7: [ELSE]

     8:

     9: message = No

    10:

    11: [GLOBAL]

    12:

    13: someTotallyOtherTS = 456

With this listing we would expect to get the object path "message" set to "Yes" since the condition line "[TYPO3 IS GREAT]" matches the criteria for what will return true. Lets try:

 

According to this output it worked!

Lets try to alter line 2 to this:

     1:

     2: [TYPO3 IS great]

     3:

The parsed result is now:

 

As you can see the value of "message" is now "No" since the condition would return false; The string "[TYPO3 IS great]" is obviously not the same as "[TYPO3 IS GREAT]"! The value of "someOtherTS" was also changed to "123" which was the value set before the condition and since the condition was not true the overriding of that former value did not happen like in the first case.

A realistic example

Most likely you don't want to evaluate conditions based on their bare string value. More likely you want to set up rules for a syntax and then parse the condition string. One example could be this modified condition class which will implement support for the condition seen in the TypoScript listings in the former section, "[UserIpRange = 123.456.*.*]":

 

     1: class myConditions {

     2:     function match($conditionLine)    {

     3:             // Getting the value inside of the square brackets:

     4:         $insideSqrBrackets = trim(ereg_replace('\]$','',substr($conditionLine,1)));

     5:         

     6:             // Splitting value into a key and value based on the "=" sign

     7:         list($key,$value) = explode('=',$insideSqrBrackets,2);

     8:         

     9:         switch(trim($key))    {

    10:             case 'UserIpRange':

    11:                 return t3lib_div::cmpIP(t3lib_div::getIndpEnv('REMOTE_ADDR'), trim($value)) ? TRUE : FALSE;

    12:             break;

    13:             case 'Browser':

    14:                 return $GLOBALS['CLIENT']['BROWSER']==trim($value);

    15:             break;

    16:         }

    17:     }

    18: }

This class works in this way:

1. Line 4: The square brackets in the start (and possibly end as well) of the condition line is removed.

2. Line 7: The condition line without square brackets is exploded into a key and a value separated by the "=" sign; we are trying to implement the concept of evaluating a data source to a value.

3. Line 9-16: This switch construct will allow the "key" to be either "UserIpRange" or "Browser"  (the datasource pointer) and the value after the equal sign is of course interpreted accordingly.

 

Lets try and parse the TypoScript listing from the former section:

 

     0: colors {

     1:   backgroundColor = red

     2:   fontColor = blue

     3: }

     4: adminInfo {

     5:   cc_email = email@email.com

     6:   cc_name = Copy Name

     7: }

     8: showAll = true

     9:

    10: [UserIpRange = 123.456.*.*]

    11:

    12:   headerImage = fileadmin/img1.jpg

    13:

    14: [ELSE]

    15:

    16:   headerImage = fileadmin/img2.jpg

    17:

    18: [GLOBAL]

    19:

    20:   // Wonder if this works... :-)

    21: wakeMeUp = 7:00

The result of parsing this will be an array like this:

 

As you can see the "headerImage" property value stems from the [ELSE] condition section and thus the "[UserIpRange = 123.456.*.*]" must still have evaluated to false - which is actually no wonder since nobody can have the IP address range "123.456.*.*" !

Lets change line 10 of the TypoScript to this:

 

     9:

    10: [UserIpRange = 192.168.*.*]

    11:

Since I'm currently on an internal network with an IP number which falls into this space the condition should now evaluate to TRUE when the TypoScript is parsed:

 

... and in fact it does!