[MapServer-users] readGIF error meaning ?

[Jeff McKenna]

Hello JC,

If you are using MS4W, you can test a GetLegendGraphic request by using 
the local demo WMS service that comes with every MS4W install, 
out-of-the-box, such as:

https://ms4w.dev/cgi-bin/mapserv.exe?MAP=/ms4w/apps/local-demo/local.map&SERVICE=WMS&VERSION=1.1.1&REQUEST=getlegendgraphic&layer=countries&FORMAT=image/png

(you should be able to modify the url above for 127.0.0.1/ instead)

If that works locally for you, just follow the local-demo.map, for your 
own mapfile.

-jeff


-- 
Jeff McKenna
GatewayGeo: Developers of MS4W, MapServer Consulting and Training
co-founder of FOSS4G
http://gatewaygeo.com/




On 2022-11-07 11:23 a.m., Jean-Christophe Bastin wrote:
> Hello,
> 
> I have many map files and I’m trying to get legends from them.
> 
> I followed the documentation I found : 
> https://mapserver.org/ogc/wms_server.html#getlegendgraphic-request 
> <https://mapserver.org/ogc/wms_server.html#getlegendgraphic-request>
> 
> The map file I test follows the requirements. I tried many calls :
> 
> http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.0.0 <http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.0.0>
> 
> http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.1.0 <http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.1.0>
> 
> http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.1.1 <http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.1.1>
> 
> http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.3.0&SLD_VERSION=1.1.0 <http://127.0.0.1/cgi-bin/mapserv.exe?MAP=C:/mywms.map&SERVICE=WMS&layer=mylayer&REQUEST=getlegendgraphic&FORMAT=image/png&VERSION=1.3.0&SLD_VERSION=1.1.0>
> 
> Each of them give me the error :
> 
> readGIF(): General error message. corrupted gif image?: Failed to read 
> from file
> 
> What does that mean ? Am I missing a parameter in my call or something 
> more in the map file that is not in the documentation ?
> 
> Or is it the kind of generic error “I can’t generate your legend, just 
> find by yourself why” ? XD
> 
> Many thanks !
> 
> *JCB*
>