diff options
| author | Jack Jansen <jack.jansen@cwi.nl> | 1996-09-09 01:48:40 (GMT) |
|---|---|---|
| committer | Jack Jansen <jack.jansen@cwi.nl> | 1996-09-09 01:48:40 (GMT) |
| commit | e1c3f36cc413dc826673a61c619421428914073c (patch) | |
| tree | ac042093e50fc8d64c09363a8f76fdb3714fbdf1 /Mac/Demo/cgi.html | |
| parent | 09da209ce4c75f4bbf241f91659a5f0a47ea5130 (diff) | |
| download | cpython-e1c3f36cc413dc826673a61c619421428914073c.zip cpython-e1c3f36cc413dc826673a61c619421428914073c.tar.gz cpython-e1c3f36cc413dc826673a61c619421428914073c.tar.bz2 | |
Documented preliminary CGI applet.
Diffstat (limited to 'Mac/Demo/cgi.html')
| -rw-r--r-- | Mac/Demo/cgi.html | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/Mac/Demo/cgi.html b/Mac/Demo/cgi.html new file mode 100644 index 0000000..3932b28 --- /dev/null +++ b/Mac/Demo/cgi.html @@ -0,0 +1,86 @@ +<HTML><HEAD><TITLE>Using python to create CGI scripts</TITLE></HEAD> +<BODY> +<H1>Using python to create CGI scripts</H1> +<HR> + +In this document we will (eventually) explain how to create Python CGI scripts +for use with NetPresenz and probably other Mac-based HTTP servers too. +Since CGI scripts are AppleEvent servers on the mac we will also learn +a little about general AppleEvent server programming and about applet +debugging. <p> + +<blockquote>Note that the current setup is very preliminary, and hence +itis probably not wise to base your strategic products on the information +in this document:-) In stead, play with the code here and join the +<a href="mailto:pythonmac-sig-request@python.org">pythonmac-sig</a>, where +we I would like to have a discussion on a real design for a Mac CGI framework +(preferrably something that will make CGI scripts portable to unix and other +platforms). +</blockquote> + +<h2>AppleEvent servers</h2> + +Since AppleEvent clients are easier to write and understand than servers +you should probably read the section on <a href="applescript.html">Open Scripting +clients in Python</a> first. <p> + +Next, let us have a look at the AE Server framework, +<a href="../Lib/toolbox/MiniAEFrame.py">MiniAEFrame.py</a>. +This file contains two classes, <code>MiniApplication</code> and <code>AEServer</code>. +MiniApplication is a tiny replacement for <code>FrameWork.Application</code>, +suitable if your application does not need windows and such. + +<blockquote>Actually, Framework.Application has a problem for AE Servers, +due to the way it expects to be quit through an exception, and raising an exception +while inside an Apple Event handler is a very bad idea. This will be fixed. +</blockquote> + +AEServer is a bit of glue that does part of the appleevent decoding for you. You +call <code>installaehandler</code> passing it the class and id (4-char strings) +of the event you have a handler for and the handler callback routine. When the +appleevent occurs your callback is called with the right arguments. For now, +your argument names are the 4-char values used internally by Open Scripting, +eventually there will be a translation similar to what the generated OSA client +suites provide. <p> + +You can test AEServer by double-clicking it. It will react to the standard +run/open/print/quit OSA commands. If it is running as a normal python script and you +drag a file onto the interpreter the script will tell you what event is got. <p> + +<h2>A Minimal CGI script</h2> + +To try a CGI script you will first need a http server. I have used the +shareware +<a href="http://www.share.com/peterlewis/netpresenz/netpresenz.html">NetPresenz</a> +by <a href="http://www.share.com/peterlewis/">Peter Lewis</a> +(don't forget to pay if you give it more than a test run!). Install your +http server, and make sure that it can serve textual documents. <p> + +Next, let us have a look at our example CGI scripts. CGI scripts have to be +applications, so we will have to make an applet as explained in +<a href="example2.html">example 2</a>. Our applet code, +<a href="cgi/cgitest.cgi.py">cgitest.cgi.py</a> is a rather minimal <code>execfile</code> +statement. The reason for this is debugging: the real code is in +<a href="cgi/realcgitest.py">realcgitest.py</a>, and this way you do not have +to run mkapplet again every time you change the code. Rename realcgitest.py +to cgitest.cgi.py once you are satisfied that it works. <p> + +The resource file is not very special, with one exception: since we want to do +our own appleevent handling we don't want the Python initialization code to +create argc and argv for use, since this might gobble up any appleevents we are +interested in. For this reason we have included a 'Popt' resource that disables +the argv initialization. An easy way to create this resource is to drop +the <code>.rsrc</code> file (or the finished applet, if you like) onto +<code>EditPythonPrefs</code> and set the "no argv processing" option. <p> + +The code itself is actually not too complicated either. We install handlers +for "open application" and "quit" (stolen from the test code in MiniAEFrame) +and the <code>"WWW\275"/"sdoc"</code> event, the event sent on CGI execution. +The cgi handler pretty-prints the CGI arguments in HTML and returns the whole +string that is to be passed to the client. The actual parameters passed +are explained in <a href="http://www.biap.com/datapig/mrwheat/cgi_params.html"> +http://www.biap.com/datapig/mrwheat/cgi_params.html</a>. <p> + +To test the script drop <code>cgitest.cgi.py</code> onto <code>mkapplet</code>, +move the resulting <code>cgitest.cgi</code> to somewhere where it is reachable +by NetPresenz, and point your web browser towards it. |