TypoScript Syntax
1.4.4. Implementing Conditions II
What about implementing the combination of conditions? For instance in the context of TypoScript Templates you can place more "conditions" in the same (real) condition:
[browser = netscape][browser = opera]
someTypoScript = 123
[GLOBAL]
They are evaluated by OR-ing the result of each sub-condition (done in the class t3lib_matchCondition). We could implement something alike and maybe even better. For instance we could implement a syntax like this:
[ CON 1 ] && [ CON 2 ] || [ CON 3 ]
This will be read like "Returns true if condition 1 and condition 2 are true OR if condition 3 is true". In other words we implement the ability to AND and OR conditions together.
The implementation goes as follows:
1: class myConditions {
2:
3: /**
4: * Splits the input condition line into AND and OR parts
5: * which are separately evaluated and logically combined to the final output.
6: */
7: function match($conditionLine) {
8: // Getting the value from inside of the wrapping
9: // square brackets of the condition line:
10: $insideSqrBrackets = trim(ereg_replace('\]$','',substr($conditionLine,1)));
11:
12: // The "weak" operator, OR, takes precedence:
13: $ORparts = split('\][[:space:]]*\|\|[[:space:]]*\[',$insideSqrBrackets);
14: foreach($ORparts as $andString) {
15: $resBool = FALSE;
16:
17: // Splits by the "&&" and operator:
18: $ANDparts = split('\][[:space:]]*\&\&[[:space:]]*\[',$andString);
19: foreach($ANDparts as $condStr) {
20: $resBool = $this->evalConditionStr($condStr) ? TRUE : FALSE;
21: if (!$resBool) break;
22: }
23:
24: if ($resBool) break;
25: }
26: return $resBool;
27: }
28:
29: /**
30: * Evaluates the inner part of the conditions.
31: */
32: function evalConditionStr($condStr) {
33: // Splitting value into a key and value based on the "=" sign
34: list($key,$value) = explode('=',$condStr,2);
35:
36: switch(trim($key)) {
37: case 'UserIpRange':
38: return t3lib_div::cmpIP(t3lib_div::getIndpEnv('REMOTE_ADDR'), trim($value)) ? TRUE : FALSE;
39: break;
40: case 'Browser':
41: return $GLOBALS['CLIENT']['BROWSER']==trim($value);
42: break;
43: }
44: }
45: }
With this implementation I can make a condition line like this:
9:
10: [UserIpRange = 192.168.*.*] && [Browser = msie]
11:
12: headerImage = fileadmin/img1.jpg
13:
So if I'm in the right IP range AND has the right browser the value of "headerImage" will be "fileadmin/img1.jpg"
If we modify the TypoScript as follows the same condition applies but if the browser is Netscape then the condition will evaluated to true regardless of the IP range:
9:
10: [UserIpRange = 192.168.*.*] && [Browser = msie] || [Browser = netscape]
11:
12: headerImage = fileadmin/img1.jpg
This is because the conditions are read like the parenthesis levels show:
( "UserIpRange = 192.168.*.*" AND "Browser = msie" ) OR "Browser = netscape"
The order of the "||" and "&&" operators may be a problem now. For instance:
9:
10: [UserIpRange = 192.168.*.*] || [UserIpRange = 212.237.*.*] && [Browser = msie]
11:
12: headerImage = fileadmin/img1.jpg
Imagine this condition; I would like it to read as "If User IP Range is either #1 or #2 provided that the browser is MSIE in any case!". But right now it will be true if the User IP range is 192.168.... OR if either the range is 212.... and the browser is MSIE.
Formally, this is what I want:
( "UserIpRange = 192.168.*.*" OR "UserIpRange = 212.237.*.*" ) AND "Browser = msie"
My solution will be to implement a second way of OR'ing conditions together - by simply implying an OR between two "condition sections" if no operator is there. Thus the line above could be implemented as follows:
9:
10: [UserIpRange = 192.168.*.*][UserIpRange = 212.237.*.*] && [Browser = msie]
11:
12: headerImage = fileadmin/img1.jpg
Line 10 will be understood in this way:
[UserIpRange = 192.168.*.*](implied OR here!)[UserIpRange = 212.237.*.*] && [Browser = msie]
The function match() of the condition class will have to be modified as follows:
1: /**
2: * Splits the input condition line into AND and OR parts
3: * which are separately evaluated and logically combined to the final output.
4: */
5: function match($conditionLine) {
6: // Getting the value from inside of the wrapping
7: // square brackets of the condition line:
8: $insideSqrBrackets = trim(ereg_replace('\]$','',substr($conditionLine,1)));
9:
10: // The "weak" operator, OR, takes precedence:
11: $ORparts = split('\][[:space:]]*\|\|[[:space:]]*\[',$insideSqrBrackets);
12: foreach($ORparts as $andString) {
13: $resBool = FALSE;
14:
15: // Splits by the "&&" and operator:
16: $ANDparts = split('\][[:space:]]*\&\&[[:space:]]*\[',$andString);
17: foreach($ANDparts as $subOrStr) {
18:
19: // Split by no operator between ] and [ (sub-OR)
20: $subORparts = split('\][[:space:]]*\[',$subOrStr);
21: $resBool = FALSE;
22: foreach($subORparts as $condStr) {
23: if ($this->evalConditionStr($condStr)) {
24: $resBool = TRUE;
25: break;
26: }
27: }
28:
29: if (!$resBool) break;
30: }
31:
32: if ($resBool) break;
33: }
34: return $resBool;
35: }
That's it.
In fact this function might be implemented for TypoScript Templates some day. Currently they only offer the OR'ing of condition-subparts, but this parsing above could probably be applied directly. Who knows, maybe it has already been done when you are reading this document...
Addendum to the reference for our application
Remember in the previous sections? We defined three tables with properties that could be used in TypoScript in the context of our case-story application. To that reference we should now add a section with conditions which defines the following:
#1: Line syntax:
A condition is splitted into smaller parts which are logically AND'ed or OR'ed together. Each sub-part of the condition line is separated by "] (Operator) [" where operator can be "&&" (AND) , "||" (OR) or nothing at all (also meaning OR "below" AND in order).
The format of the condition line therefore is:
[ COND1 ] || [ COND2 ] && [ COND3 ] [ COND4 ] ....etc
where the operators has precedence as indicated by these illustrative parenthesis:
[ COND1 ] || ( [ COND2 ] && ( [ COND3 ] [ COND4 ] ) )
(Notice: Between COND3 and COND4 the blank space is implicitly an OR)
#2: Subpart syntax:
For each subpart (for example "[ COND 1 ]") the content is evaluated as follows:
[ KEY = VALUE ]
where KEY denotes a type of condition from the table below:
|
KEY |
Description |
Example |
|---|---|---|
|
UserIpRange |
Returns true if the clients remote IP address matches the pattern given as value. The value is matched against REMOTE_ADDR by the function t3lib_div::cmpIP() which you can consult for details on the syntax. |
[UserIpRange = 192.168.*.*] |
|
Browser |
Returns true if the client browser matches one of the keywords below:
Value you can use: konqu = Konqueror opera = Opera msie = Microsoft Internet Explorer net = Netscape (or any other)
Values are evaluated against the output of the function t3lib_div::clientInfo() which can be consulted for details on the values for browsers. |
[Browser = msie] |