Index: /gs2-extensions/apache-jena/trunk/src/README-FUSEKI2.txt
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--- /gs2-extensions/apache-jena/trunk/src/README-FUSEKI2.txt	(revision 37134)
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+
+Installation of this extension follows the usual pattern:
+
+  ./CASCADE-MAKE.sh
+
+
+For interative experiments with the Triplestore, you can then visit
+the home page:
+
+  http://localhost:3030/
+
+Go to the control panel:
+
+  http://localhost:3030/control-panel.tpl
+
+The control panel lets you choose which dataset to work with through a
+drop-down menu.  For the Greenstone extension installation there
+should only be one:
+
+  /greenstone
+
+Pressing 'select' triggers a POST action to:
+
+  http://localhost:3030/$/dataset
+  
+which triggers a redirect (through setting 'Location:' in the respose header) to:
+
+
+  http://localhost:3030/sparql.tpl
+
+
+A generic query to try out is:
+
+  select * where { ?s ?p ?o } limit 100
+
+
+#----
+# ReverseProxying
+#----
+
+If serving your Greenstone3 through a public facing web server, such as Apache2:
+
+    ProxyPass /greenstone3-lod3 http://localhost:4040
+    ProxyPassReverse /greenstone3-lod3 http://localhost:4040
+
+then the installed '.tpl' files and the Location redirects don't work.  Introducing
+a base tag into the header such as:
+
+<base href="/greenstone3-lod/" />
+
+and changing the 'control-panel.tpl' form action to be:
+
+ <form action="/greenstone3-lod/${action}" method="post">
+ 
+helps a bit, but the Location redirect is still an issue.
+
+Bottom-line to run a SPARQL query directly, (for localhost) you would do:
+
+  http://localhost:3030/greenstone/query?query=select+*+where+%7B+%3Fs+%3Fo+%3Fp+%7D+limit+100&output=text&stylesheet=
+
+For a proxied install you would (continuing the example) do:
+
+  http://sowemustthink.space/greenstone3-lod/greenstone/query?query=select+*+where+%7B+%3Fs+%3Fo+%3Fp+%7D+limit+100&output=text&stylesheet=
+
+
+Factoring in these details, it is possible to setup a transform/page/sparql.xsl page in Greenstone3 this is fully operational,
+even in the ReverseProxying situation.
+
+One key step in sparql.xsl is to updated the form input argument for 'stylesheet' to specify the proxied prefix URL:
+
+  stylesheet=/greenstone3-lod/xml-to-html-links.xsl
+  stylesheet=%2Fgreenstone3-lod%2Fxml-to-html-links.xsl
+
+
+When asking for the SPARQL XML result to be transformed to html-links, the hyperlinks in the page generated
+also need some tweaking.  The Greenstone3 sparql.xsl page helps plumb the static files used back to the
+/greenstone3-lod/ url, but inside 'xml-to-html-links.xsl' this sets another 'stylesheet=' argument that
+needs to be updated to the ReverseProxy setup
+
+
+    <a href="?query={$query}&amp;output=xml&amp;stylesheet=%2Fxml-to-html-links.xsl">
+->    
+    <a href="?query={$query}&amp;output=xml&amp;stylesheet=%2Fgreenstone3-lod%2Fxml-to-html-links.xsl">
+
+You might need to reload the xml-to-html-links.xsl file in the browser if it has been cached before the change
+
+
+% fgrep -rl xml-to-html etc/
+  etc/pages/sparql.html
+  etc/pages/sparql.tpl
+  etc/pages/xml-to-html-links.xsl
+
+
+
+
+#----
+# Note about Jena code:
+#----
+
+  Jena is a pure Java code base, and the relevant compiled jar files
+  are bundled with this extension, so no actual compilation is needed.
+  The main task CASCADE-MAKE.sh does is to untar the 'binary' files,
+  and setup them up in appropriate top-level ' lib' folder (for jar
+  files) etc so Greenstone can find them
+
+  In case it is ever needed, the companion source code is in 'src'
+  directory (taken from the Apache Jena website, matched to the binary
+  version).  For source code, there was only a zip version of the file
+  to download.
+
+   To run the command-line client programs, such as 's-put', this
+   requires Ruby to be installed.  The source code for this is
+   provided in the 'packages' directory, and compiled up and installed
+   as part of running ./CASCADE-MAKE.sh
+      
+     
+
+
+
