diff -r 000000000000 -r b97547f5f1fa web/views/dynimages.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/views/dynimages.py	Wed Nov 05 15:52:50 2008 +0100
@@ -0,0 +1,182 @@
+"""dynamically generated image views
+
+:organization: Logilab
+:copyright: 2001-2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+"""
+__docformat__ = "restructuredtext en"
+
+import os
+from tempfile import mktemp
+
+from logilab.common.graph import escape, GraphGenerator, DotBackend
+from yams import schema2dot as s2d
+
+from cubicweb.common.view import EntityView, StartupView
+
+
+class RestrictedSchemaDotPropsHandler(s2d.SchemaDotPropsHandler):
+    def __init__(self, req):
+        self.req = req
+        
+    def display_attr(self, rschema):
+        return not rschema.meta and (rschema.has_local_role('read')
+                                     or rschema.has_perm(self.req, 'read'))
+    
+    # XXX remove this method once yams > 0.20 is out
+    def node_properties(self, eschema):
+        """return default DOT drawing options for an entity schema"""
+        label = ['{',eschema.type,'|']
+        label.append(r'\l'.join(rel.type for rel in eschema.subject_relations()
+                                if rel.final and self.display_attr(rel)))
+        label.append(r'\l}') # trailing \l ensure alignement of the last one
+        return {'label' : ''.join(label), 'shape' : "record",
+                'fontname' : "Courier", 'style' : "filled"}
+    
+class RestrictedSchemaVisitorMiIn:
+    def __init__(self, req, *args, **kwargs):
+        # hack hack hack
+        assert len(self.__class__.__bases__) == 2
+        self.__parent = self.__class__.__bases__[1]
+        self.__parent.__init__(self, *args, **kwargs)
+        self.req = req
+        
+    def nodes(self):
+        for etype, eschema in self.__parent.nodes(self):
+            if eschema.has_local_role('read') or eschema.has_perm(self.req, 'read'):
+                yield eschema.type, eschema
+            
+    def edges(self):
+        for setype, oetype, rschema in self.__parent.edges(self):
+            if rschema.has_local_role('read') or rschema.has_perm(self.req, 'read'):
+                yield setype, oetype, rschema
+
+class FullSchemaVisitor(RestrictedSchemaVisitorMiIn, s2d.FullSchemaVisitor):
+    pass
+
+class OneHopESchemaVisitor(RestrictedSchemaVisitorMiIn, s2d.OneHopESchemaVisitor):
+    pass
+
+class OneHopRSchemaVisitor(RestrictedSchemaVisitorMiIn, s2d.OneHopRSchemaVisitor):
+    pass
+                
+        
+class TmpFileViewMixin(object):
+    binary = True
+    content_type = 'application/octet-stream'
+    cache_max_age = 60*60*2 # stay in http cache for 2 hours by default 
+    
+    def call(self):
+        self.cell_call()
+        
+    def cell_call(self, row=0, col=0):
+        self.row, self.col = row, col # in case one need it
+        tmpfile = mktemp('.png')
+        try:
+            self._generate(tmpfile)
+            self.w(open(tmpfile).read())
+        finally:
+            os.unlink(tmpfile)
+    
+class SchemaImageView(TmpFileViewMixin, StartupView):
+    id = 'schemagraph'
+    content_type = 'image/png'
+    skip_rels = ('owned_by', 'created_by', 'identity', 'is', 'is_instance_of')
+    def _generate(self, tmpfile):
+        """display global schema information"""
+        skipmeta = not int(self.req.form.get('withmeta', 0))
+        visitor = FullSchemaVisitor(self.req, self.schema, skiprels=self.skip_rels, skipmeta=skipmeta)
+        s2d.schema2dot(outputfile=tmpfile, visitor=visitor,
+                       prophdlr=RestrictedSchemaDotPropsHandler(self.req))
+
+class EETypeSchemaImageView(TmpFileViewMixin, EntityView):
+    id = 'eschemagraph'
+    content_type = 'image/png'
+    accepts = ('EEType',)
+    skip_rels = ('owned_by', 'created_by', 'identity', 'is', 'is_instance_of')
+    
+    def _generate(self, tmpfile):
+        """display schema information for an entity"""
+        entity = self.entity(self.row, self.col)
+        eschema = self.vreg.schema.eschema(entity.name)
+        visitor = OneHopESchemaVisitor(self.req, eschema, skiprels=self.skip_rels)
+        s2d.schema2dot(outputfile=tmpfile, visitor=visitor,
+                       prophdlr=RestrictedSchemaDotPropsHandler(self.req))
+
+class ERTypeSchemaImageView(EETypeSchemaImageView):
+    accepts = ('ERType',)
+    
+    def _generate(self, tmpfile):
+        """display schema information for an entity"""
+        entity = self.entity(self.row, self.col)
+        rschema = self.vreg.schema.rschema(entity.name)
+        visitor = OneHopRSchemaVisitor(self.req, rschema)
+        s2d.schema2dot(outputfile=tmpfile, visitor=visitor,
+                       prophdlr=RestrictedSchemaDotPropsHandler(self.req))
+
+
+
+class WorkflowDotPropsHandler(object):
+    def __init__(self, req):
+        self._ = req._
+        
+    def node_properties(self, stateortransition):
+        """return default DOT drawing options for a state or transition"""
+        props = {'label': stateortransition.name, 
+                 'fontname': 'Courier'}
+        if hasattr(stateortransition, 'state_of'):
+            props['shape'] = 'box'
+            props['style'] = 'filled'
+            if stateortransition.reverse_initial_state:
+                props['color'] = '#88CC88'
+        else:
+            props['shape'] = 'ellipse'
+            descr = []
+            tr = stateortransition
+            if tr.require_group:
+                descr.append('%s %s'% (
+                    self._('groups:'),
+                    ','.join(g.name for g in tr.require_group)))
+            if tr.condition:
+                descr.append('%s %s'% (self._('condition:'), tr.condition))
+            if descr:
+                props['label'] += escape('\n'.join(descr))
+        return props
+    
+    def edge_properties(self, transition, fromstate, tostate):
+        return {'label': '', 'dir': 'forward',
+                'color': 'black', 'style': 'filled'}
+
+class WorkflowVisitor:
+    def __init__(self, entity):
+        self.entity = entity
+
+    def nodes(self):
+        for state in self.entity.reverse_state_of:
+            state.complete()
+            yield state.eid, state
+            
+        for transition in self.entity.reverse_transition_of:
+            transition.complete()
+            yield transition.eid, transition
+            
+    def edges(self):
+        for transition in self.entity.reverse_transition_of:
+            for incomingstate in transition.reverse_allowed_transition:
+                yield incomingstate.eid, transition.eid, transition
+            yield transition.eid, transition.destination().eid, transition
+
+
+class EETypeWorkflowImageView(TmpFileViewMixin, EntityView):
+    id = 'ewfgraph'
+    content_type = 'image/png'
+    accepts = ('EEType',)
+    
+    def _generate(self, tmpfile):
+        """display schema information for an entity"""
+        entity = self.entity(self.row, self.col)
+        visitor = WorkflowVisitor(entity)
+        prophdlr = WorkflowDotPropsHandler(self.req)
+        generator = GraphGenerator(DotBackend('workflow', 'LR',
+                                              ratio='compress', size='30,12'))
+        return generator.generate(visitor, prophdlr, tmpfile)