adding gateway parsing code. so far, we have XML gateway handling using python minidom.

git-svn-id: svn://svn.open-ils.org/OpenSRF/trunk@935 9efc2488-bf62-4759-914b-345cdb29e865

diff --git a/src/python/osrf/gateway.py b/src/python/osrf/gateway.py
new file mode 100644 (file)
index 0000000..3a6efaf
--- /dev/null
+++ b/src/python/osrf/gateway.py
@@ -0,0 +1,136 @@
+from xml.dom import minidom
+from xml.sax import handler, make_parser, saxutils
+from json import *
+from net_obj import *
+import urllib, urllib2, sys
+
+defaultHost = None
+
+class GatewayRequest:
+    def __init__(self, service, method, params=[]):
+        self.service = service
+        self.method = method
+        self.params = params
+
+    def send(self):
+        params = self.buildPOSTParams()
+        request = urllib2.Request(self.buildURL(), data=params)
+        response = None
+        try:
+            response =urllib2.urlopen(request)
+        except urllib2.HTTPError, e:
+            # log this?
+            sys.stderr.write('HTTPError: code=%d : %s' % (e.code, str(e)))
+            raise e
+            
+        return self.handleResponse(response)
+
+    def buildPOSTParams(self):
+
+        params = urllib.urlencode({   
+            'service': self.service,
+            'method': self.method,
+            'format': self.getFormat()
+        })
+
+        for p in self.params:
+            param = {'param': osrfObjectToJSON(p)}
+            params += '&%s' % urllib.urlencode(param)
+
+        return params
+
+    def setDefaultHost(host):
+        global defaultHost
+        defaultHost = host
+    setDefaultHost = staticmethod(setDefaultHost)
+
+    def buildURL(self):
+        return 'http://%s/gateway' % defaultHost
+
+
+class XMLGatewayRequest(GatewayRequest):
+
+    def __init__(self, service, method, *params):
+        GatewayRequest.__init__(self, service, method, list(params))
+
+    def getFormat(self):
+        return 'xml'
+
+    def handleResponse(self, response):
+        handler = XMLGatewayParser()
+        parser = make_parser()
+        parser.setContentHandler(handler)
+        parser.parse(response)
+        return handler.getResult()
+
+class XMLGatewayParser(handler.ContentHandler):
+
+    def __init__(self):
+        self.result = None
+        self.objStack = []
+        self.keyStack = []
+
+    def getResult(self):
+        return self.result
+
+    def __getAttr(self, attrs, name):
+        for (k, v) in attrs.items():
+            if k == name:
+                return v
+        return None
+
+    def startElement(self, name, attrs):
+
+        # XXX add support for serializable objects!
+
+        if name == 'element': # this is an object item wrapper
+            self.keyStack.append(self.__getAttr(attrs, 'key'))
+            return
+
+        if name == 'object':
+            obj = {}
+            self.appendChild(obj)
+            self.objStack.append(obj)
+            return
+
+        if name == 'array':
+            obj = []
+            self.appendChild(obj)
+            self.objStack.append(obj)
+            return
+
+        if name == 'null':
+            self.appendChild(None)
+            return
+
+        if name == 'boolean':
+            self.appendChild((self.__getAttr(attrs, 'value') == 'true'))
+            return
+
+
+    def appendChild(self, child):
+
+        if self.result == None:
+            self.result = child
+
+        if not self.objStack: return;
+
+        parent = self.objStack[len(self.objStack)-1]
+
+        if( isinstance(parent, list) ):
+            parent.append(child)
+        else:
+            parent[self.keyStack.pop()] = child
+
+    def endElement(self, name):
+        if name == 'array' or name == 'object':
+            self.objStack.pop()
+
+    def characters(self, chars):
+        #self.appendChild(''.join(chars[start:leng+start]))
+        self.appendChild(urllib.unquote_plus(chars))
+
+
+
+    
+