Hi Christian,

Yes, after a user login into OpenLayers-based web client I can successfully 
make a WMS GetCapabilities request as I provided the correct “Authorization” 
header and this request was made by using the OpenLayers.Request() construct 
which uses XMLHttpRequest object underneath.  However, even though I do this 
when OpenLayers makes WMS GetMap requests when I enable a certain layer the 
browser (latest versions of Chrome and Firefox) does not automatically send the 
credentials I provided with the previous request and I still get the browser 
login popup.  From my online research it appears that you cannot send an 
“Authorization” header for these WMS requests with OpenLayers because it uses 
the HTML <img> tag.  What did work is setting the URL for my layer to 
http://username:password@localhost:8080/geoserver/<workspace>/wms<http://username:password@localhost:8080/geoserver/%3cworkspace%3e/wms>,
 however this means I would need to send the password in plain text across the 
wire which is unacceptable.

Why doesn't the browser reuse the authorization headers after an authenticated 
XMLHttpRequest?
http://stackoverflow.com/questions/20617720/why-doesnt-the-browser-reuse-the-authorization-headers-after-an-authenticated-x

However, the solution proposed in the above stackoverflow question cannot be 
applied in this situation because the solution says to simply avoid using the 
<img> tag altogether and instead load images with JS XMLHttpRequest.


The key problem I see here is that the browser will not send credentials until 
a credential challenge (HTTP 401 server response) is sent back by the server, 
and with little control over how OpenLayers renders the images from WMS GetMap 
request, it doesn’t appear that I can provide a custom handling for the HTTP 
401 response to override this browser behavior on the client-side from 
Javascript when the request is not an XMLHttpRequest.

I’ve looked at the “authKey” plugin and it looks like it might work 
out-of-the-box for me.  I will attempt to try it today.

Thanks,
--Steve

From: Christian Mueller [mailto:christian.muel...@os-solutions.at]
Sent: Thursday, August 14, 2014 7:03 AM
To: Stephen Brooke
Cc: Andrea Aime; geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] After period of GeoServer inactivity client 
making WMS request gets HTTP 404 Not Found (pink no image tiles)

Hi Stephen

After the user is logged in into your application (open layers) successfully, 
did you try to send a OGC request to GeoServer containing the proper basic auth 
headers in your java script code simulating a popup login. Not sure if this 
works, never tried.

Of course it would be possible to add a configuration option "Do not send 
WWW-Authenticate" to the filter, but this is not standard and as a consequence, 
I do not want to implement it.

On the other side, it is possible to develop your own authentication filter as 
a plugin. The "authkey" module is a good example.
http://docs.geoserver.org/stable/en/user/community/authkey/index.html

Cheers
Christian







On Wed, Aug 13, 2014 at 6:26 PM, Stephen Brooke 
<sbro...@mdacorporation.com<mailto:sbro...@mdacorporation.com>> wrote:
Now that I get the login popup in the browser for the first WMS request I can 
see that this will not be very pleasant for the user who has already been made 
to login to my application.  According to several forum posts on the subject it 
is the HTTP header ‘WWW-Authenticate:Basic realm="GeoServer Realm“’ that causes 
this browser behavior.  Is there a way to tell GeoServer not to set the 
WWW-Authenticate response header when it sends HTTP 401?  Or is this something 
the “User-Agent”, that is, the browser needs to deal with?  According to the 
HTTP spec a “User-Agent” can set the HTTP Authorization header with appropriate 
credentials in place of popping up a login dialog, however, the consensus in 
the dev community seems to be that preventing the browser to popup the dialog 
is not currently possible unless the server deviates from the HTTP spec in some 
way (for example, if the server omits the WWW-Authenticate header).

Some forums suggest that it is becoming good practice for clients to set the 
HTTP header “X-Requested-With: XMLHttpRequest” as a hint to the server to not 
include the WWW-Authenticate header, and hence the browser would not popup the 
login prompt.

Anybody have any good solutions for preventing the browser to popup a login 
dialog in response to HTTP 401 from GeoServer and instead have the browser 
client (OpenLayers) respond with proper “Authorization” header?

Here’s an explanation of this web browser HTTP 401 problem:
http://www.freelock.com/2008/06/technical-note-http-auth-with-ajax

Here’s a Chrome issue that talks about this issue a bit more.
https://code.google.com/p/chromium/issues/detail?can=2&start=0&num=100&q=&colspec=ID%20Pri%20Mstone%20ReleaseBlock%20OS%20Area%20Feature%20Status%20Owner%20Summary&groupby=&sort=&id=31582

For instance could I put a Servlet Filter in GeoServer web.xml such that it 
causes the “WWW-Authenticate” header to not get set in certain situtions?

--Steve

From: Stephen Brooke
Sent: Tuesday, August 12, 2014 10:14 AM
To: 'Christian Mueller'
Cc: Andrea Aime; 
geoserver-users@lists.sourceforge.net<mailto:geoserver-users@lists.sourceforge.net>
Subject: RE: [Geoserver-users] After period of GeoServer inactivity client 
making WMS request gets HTTP 404 Not Found (pink no image tiles)

Hi Christian,

I tried opening a new browser window and making a WMS GetCapabilities request 
and it did not popup a login panel which I thought was strange.  I then used 
the filter chain tester tool in the GeoServer Web Admin and checked the WMS 
request URL and it said it was using the “default” filter which had both 
“anonymous” and “basic” authentication providers selected so I removed the 
“anonymous” authentication provider.  After this I re-ran the test and the WMS 
request caused a login panel to popup the first time I tried to access the 
resource.

I will try the scenario again to see if the timeout happens now that I have the 
correct “default” service chain filter in place.

--Steve

From: Christian Mueller [mailto:christian.muel...@os-solutions.at]
Sent: Tuesday, August 12, 2014 2:57 AM
To: Stephen Brooke
Cc: Andrea Aime; 
geoserver-users@lists.sourceforge.net<mailto:geoserver-users@lists.sourceforge.net>

Subject: Re: [Geoserver-users] After period of GeoServer inactivity client 
making WMS request gets HTTP 404 Not Found (pink no image tiles)

Hi Stephen

Can you try the following.

Open a browser and call a OGC service on a protected resource. The browser 
should pop up a login panel (for basic or digest auth). After login, the 
browser should send authentication header attributes for each request. To stop 
sending this attributes, you must close your browser because there is no 
explicit log out for stateless authentication.

AFAIK it is not possible to disable "session integration". Would be a new 
feature.

Christian

On Mon, Aug 11, 2014 at 6:58 PM, Stephen Brooke 
<sbro...@mdacorporation.com<mailto:sbro...@mdacorporation.com>> wrote:
Andrea,

Here are some more details that should answer your questions:

>Session? As in HTTP one?
[Steve]: Yes I mean HTTP session

>OGC services should create a session to start with, unless you configured the 
>security otherwise, or you are using the same browser
>to admin and do OGC requests at the same time.
[Steve]: Yes, I am using the same browser to admin GeoServer and also to run a 
web client that uses OGC services.  I will try running the web client in a 
different browser and see if the problem is still reproducible in that case.

My web client can pass credentials each time so a session isn’t really needed 
for the OGC services.  Is there a stateless mode for the OGC services?  I see 
in the “GeoServer User Manual, Release 2.5-RC2” it states:

----------------------------------------
16.2.3 Authentication to OWS and REST services

“OWS and REST services are stateless and have no inherent awareness of 
“session”, so the authentication
scheme for these services requires the client to supply credentials on every 
request. That said, “session integration”
is supported, meaning that if a session already exists on the server (from a 
concurrent authenticated
web admin session) it will be used for authentication. This scheme allows 
GeoServer to avoid the overhead
of session creation for OWS and REST services.”
----------------------------------------

Is there a way to disable “session integration” for OGC services?

--Steve

From: andrea.a...@gmail.com<mailto:andrea.a...@gmail.com> 
[mailto:andrea.a...@gmail.com<mailto:andrea.a...@gmail.com>] On Behalf Of 
Andrea Aime
Sent: Saturday, August 09, 2014 1:07 AM
To: Stephen Brooke
Cc: 
geoserver-users@lists.sourceforge.net<mailto:geoserver-users@lists.sourceforge.net>
Subject: Re: [Geoserver-users] After period of GeoServer inactivity client 
making WMS request gets HTTP 404 Not Found (pink no image tiles)

On Fri, Aug 8, 2014 at 10:38 PM, Stephen Brooke 
<sbro...@mdacorporation.com<mailto:sbro...@mdacorporation.com>> wrote:
I’m running GeoServer 2.5.1 with OpenLayers client making WMS requests and I 
have basic authentication turned on for all OGC services.

After a period (say 30 minutes) of GeoServer inactivity due to client 
inactivity, if the client is then used to make a WMS request it receives HTTP 
404 Not Found and I get the dreaded pink square tiles instead of my imagery 
tiles.  In the GeoServer log there are several warning log messages of the form:

08 Aug 20:23:03 WARN [servlet.PageNotFound] - No mapping found for HTTP request 
with URI [/geoserver/<workspace>/wms] in DispatcherServlet with name 
'dispatcher'


If I go to the GeoServer web admin console and login as administrator or simply 
refresh an existing timed-out session then the WMS requests work fine again.  
Does anyone know what I need to do to get GeoServer to not do this?

Session? As in HTTP one?
OGC services should create a session to start with, unless you configured the 
security otherwise, or you are using the same browser
to admin and do OGC requests at the same time.

Is this your case?

Can you provide more details on your setup?

Cheers
Andrea

--
==
GeoServer Professional Services from the experts! Visit
http://goo.gl/NWWaa2 for more information.
==

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054  Massarosa (LU)
Italy
phone: +39 0584 962313<tel:%2B39%200584%20962313>
fax: +39 0584 1660272<tel:%2B39%200584%201660272>
mob: +39  339 8844549<tel:%2B39%20%C2%A0339%208844549>

http://www.geo-solutions.it
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DI Christian Mueller MSc (GIS), MSc (IT-Security)
OSS Open Source Solutions GmbH




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DI Christian Mueller MSc (GIS), MSc (IT-Security)
OSS Open Source Solutions GmbH

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