added more XQuery modules

xquery/app.xqm → xquery/app-shared.xqm

@@ -2,12 +2,11 @@ xquery version "3.1" encoding "UTF-8";
 
 module namespace app-shared="http://xquery.weber-gesamtausgabe.de/modules/app-shared";
 
-declare namespace tei="http://www.tei-c.org/ns/1.0";
-declare namespace mei="http://www.music-encoding.org/ns/mei";
-
 import module namespace functx="http://www.functx.com";
+import module namespace str="http://xquery.weber-gesamtausgabe.de/modules/str" at "str.xqm";
 import module namespace templates="http://exist-db.org/xquery/templates" at "/db/apps/shared-resources/content/templates.xql";
 
+declare variable $app-shared:FUNCTION_LOOKUP_ERROR := QName("http://xquery.weber-gesamtausgabe.de/modules/app-shared", "FunctionLookupError");
 
 (:~
  : Set an attribute to the value given in the $model map
@@ -60,8 +59,6 @@ declare
  : A non-wrapping alternative to the standard templates:each()
  : Gets rid of the superfluous first list item
  : 
- : At present, only $callbackArity=2 is supported
- :
  : @author Peter Stadler
  :)
 declare 
@@ -73,8 +70,8 @@ declare
         if($max castable as xs:integer and $max != '0') then subsequence($model($from), 1, $max)
         else $model($from)
     let $callbackFunc := 
-        try { function-lookup(xs:QName($callback), xs:int($callbackArity)) } 
-        catch * { core:logToFile('error', 'Failed to lookup function "' || $callback ) }
+        try { function-lookup(xs:QName($callback), 2) } 
+        catch * { error($app-shared:FUNCTION_LOOKUP_ERROR, 'Failed to lookup function "' || $callback || '". Error code was "' || $err:code || '". Error message was "' || $err:description || '".') }
     return (
         for $item in $items
         return 

xquery/cache.xqm

+xquery version "3.1" encoding "UTF-8";
+
+(:~
+ : XQuery module for caching documents and collections
+~:)
+module namespace cache="http://xquery.weber-gesamtausgabe.de/modules/cache";
+
+import module namespace functx="http://www.functx.com";
+import module namespace wega-util-shared="http://xquery.weber-gesamtausgabe.de/modules/wega-util-shared" at "wega-util-shared.xqm";
+
+declare variable $cache:TOO_MANY_PARAMETERS_ERROR := QName("http://xquery.weber-gesamtausgabe.de/modules/cache", "TooManyParametersError");
+declare variable $cache:UNSUPPORTED_PARAMETER_VALUE_ERROR := QName("http://xquery.weber-gesamtausgabe.de/modules/cache", "UnsupportedParameterValueError");
+
+(:~
+ : A caching function for documents (XML and binary)
+ :
+ : @author Peter Stadler
+ : @param $docURI the database URI of the document
+ : @param $callBack a function to create the document content when the document is outdated or not available
+ : @param $lease an xs:dayTimeDuration value of how long the cache should persist, e.g. P999D (= 999 days). 
+ :          Alternatively, $lease can be a callback function – then one argument (the last change date of the file as xs:date()?) will be provided 
+ :          and the function should return xs:boolean
+ : @return the cached document
+ :)
+declare function cache:doc($docURI as xs:string, $callback as function() as item(), $callback-params as item()*, $lease as item()?, $onFailure as function() as item()*) as item()* {
+    let $fileName := functx:substring-after-last($docURI, '/')
+    let $collection := functx:substring-before-last($docURI, '/')
+    let $currentDateTimeOfFile := 
+        if(wega-util-shared:doc-available($docURI)) then xmldb:last-modified($collection, $fileName)
+        else if(util:binary-doc-available($docURI)) then xmldb:last-modified($collection, $fileName)
+        else ()
+    let $updateNecessary := 
+        typeswitch($lease)
+        case xs:dayTimeDuration return
+            $currentDateTimeOfFile + $lease lt current-dateTime()
+            or empty($lease) 
+            or empty($currentDateTimeOfFile)
+        case function() as xs:boolean return $lease($currentDateTimeOfFile)
+        default return error($cache:UNSUPPORTED_PARAMETER_VALUE_ERROR, 'The parameter value for $lease must be xs:dayTimeDuration()? or a function reference which must take exactly one argument.')
+    return 
+	   if($updateNecessary) then (
+            let $content := 
+                if(count($callback-params) eq 0) then $callback()
+                else if(count($callback-params) eq 1) then $callback($callback-params)
+                else if(count($callback-params) eq 2) then $callback($callback-params[1], $callback-params[2])
+                else if(count($callback-params) eq 3) then $callback($callback-params[1], $callback-params[2], $callback-params[3])
+                else if(count($callback-params) eq 4) then $callback($callback-params[1], $callback-params[2], $callback-params[3], $callback-params[4])
+                else error($cache:TOO_MANY_PARAMETERS_ERROR, 'Too many arguments to callback function within cache:doc(). A maximum of 4 arguments is supported')
+            let $mime-type := wega-util-shared:guess-mimeType-from-suffix(functx:substring-after-last($docURI, '.'))
+            let $store-file := cache:store-file($collection, $fileName, $content, $mime-type, $onFailure)
+            return 
+                if(util:binary-doc-available($store-file)) then util:binary-doc($store-file)
+                else if(wega-util-shared:doc-available($store-file)) then doc($store-file) 
+                else ()
+        )
+        else if(util:binary-doc-available($docURI)) then util:binary-doc($docURI)
+        else if(wega-util-shared:doc-available($docURI)) then doc($docURI)
+        else ()
+};
+
+(:~
+ : Store some content as file in the db
+ : (Helper function for cache:doc())
+ : 
+ : @author Peter Stadler
+ : @param $collection the collection to put the file in. If it does not exist, it will be created  
+ : @param $fileName the filename of the to be created resource with filename extension
+ : @param $contents the content to store. Either a node, an xs:string, a Java file object or an xs:anyURI 
+ : @return Returns the path to the newly created resource, empty sequence otherwise
+ :)
+declare %private function cache:store-file($collection as xs:string, $fileName as xs:string, $contents as item(), $mime-type as xs:string, $onFailure as function() as item()*) as xs:string? {
+    let $createCollection := 
+        for $coll in tokenize($collection, '/')
+        let $parentColl := substring-before($collection, $coll)
+        return 
+            if(xmldb:collection-available($parentColl || '/' || $coll)) then ()
+            else xmldb:create-collection($parentColl, $coll)
+    return
+        try { xmldb:store($collection, $fileName, $contents, $mime-type) }
+        catch * { $onFailure($err:code, $err:description) }
+};
+

xquery/wega-util-shared.xqm

+xquery version "3.1" encoding "UTF-8";
+
+(:~
+ : XQuery module with utility functions 
+~:)
+module namespace wega-util-shared="http://xquery.weber-gesamtausgabe.de/modules/wega-util-shared";
+
+(:~
+ :  A slight modification of the standard XPath function fn:doc-available()
+ :  which will return false() for binary documents instead of failing
+~:)
+declare function wega-util-shared:doc-available($uri as xs:string?) as xs:boolean {
+    try {doc-available($uri)}
+    catch * {false()}
+};
+
+(:~
+ : Helper function for guessing a mime-type from a file extension
+ : (Should be expanded to read in $exist.home$/mime-types.xml)
+ :
+ : @author Peter Stadler 
+ : @param $suffix the file extension
+ : @return the mime-type or the empty sequence when no match was found
+ :)
+declare function wega-util-shared:guess-mimeType-from-suffix($suffix as xs:string) as xs:string? {
+    switch($suffix)
+        case 'xml' return 'application/xml'
+        case 'rdf' return 'application/rdf+xml'
+        case 'jpg' return 'image/jpeg'
+        case 'png' return 'image/png'
+        case 'txt' return 'text/plain'
+        default return ()
+};