Not possible to find service when Accept headers with multiple schemes

[tiberiuichim]

This simple jquery call should work:

  $.ajax(
    {
      url,
      method: 'POST',
      dataType: 'json',
      success: function (resp) { }
    }
  );

The Accept is sent as 'application/json, text/javascript, */*; q=0.01', result of parse_accept_header(accept) is [('application', 'json'), ('text', 'javascript'), ('*', '*')].

Except for cowardly exiting in lookup_service_id:

    if len(media_types) != 1:
        return None

IMHO, it should loop over the result of media_types and only return None if no services are found.

[tisto]

@tiberiuichim plone.rest is a low level framework to create custom REST endpoints, not an out-of-the box solution that allows you to do POST calls via jQuery. You might want to look into plone.restapi.

[tisto]

Feel free to re-open if I misunderstood your report.

[tiberiuichim]

I'm using plone.restapi.

[tiberiuichim]

My concern is that this common use case, of doing a call with jquery is not supported. I know, it is possible to set the exact headers in jquery.ajax(), but I think the default should be supported OOTB

[tiberiuichim]

We can also go strictly by protocol definitions. "My client" says that it accepts any of application/json, text/javascript or really really any response (based on the wildcard), while plone.rest will refuse to return a proper response because it wants that my client only accept application/json, where "proper" is the appropriate service for the application/json encoding. This is wrong, from my perspective.

[tisto]

@tiberiuichim then please provide a curl/wget/httpie example of even better a python test to prove your point.

[tisto]

@tiberiuichim sorry for misunderstanding your bug report at first. The problem is that the underlying existing implementation in the zpublisher is very complex. Therefore we decided to implement content negotiation in the simplistic way we did.

What you describe is certainly desirable, but we will not be able to implement that anytime soon. The amount of work that would be necessary to fix does not rationalize what we gain from it. Therefore I will close the issue. Feel free to re-open when you or somebody else wants to tackle this. Though, I would not advise doing so.

What you describe is certainly desirable, but we will not be able to implement that anytime soon. The amount of work that would be necessary to fix does not rationalize what we gain from it. Therefore I will close the issue. Feel free to re-open when you or somebody else wants to tackle this. Though, I would not advise doing so.

[tiberiuichim]

Maybe I'm missing something, but wouldn't something like this be enough?

diff --git a/src/plone/rest/negotiation.py b/src/plone/rest/negotiation.py
index ffc6231..e0718ae 100644
--- a/src/plone/rest/negotiation.py
+++ b/src/plone/rest/negotiation.py
@@ -24,17 +24,15 @@ def lookup_service_id(method, accept):
        negotiation.
     """
     media_types = parse_accept_header(accept)
-    if len(media_types) != 1:
-        return None
-    type_, subtype = media_types[0]
-    types = _services.get(method, {})
-    subtypes = types.get(type_, {})
-    if subtype in subtypes:
-        return subtypes[subtype]
-    elif '*' in subtypes:
-        return subtypes['*']
-    if '*' in types:
-        return types['*']['*']
+    for type_, subtype in media_types:
+        types = _services.get(method, {})
+        subtypes = types.get(type_, {})
+        if subtype in subtypes:
+            return subtypes[subtype]
+        elif '*' in subtypes:
+            return subtypes['*']
+        if '*' in types:
+            return types['*']['*']
     return None

[buchi]

@tiberiuichim the check for a single media type in the Accept header is intentional. We use that to distinguish between regular requests and REST API requests. With your proposed change every regular browser request would go to the REST API endpoint as browsers always include */* in their Accept header.

[petri]

This use case may actually become supported if/when #105 is merged.