How to get role details by name which has space

santosh_csc - It seems to be some other issue, either the role you are fetching is not present in the community or might be the spelling mistake.  Could you please verify. 

Tried the same call and it worked fine on my side. 

API:

community-url/restapi/vc/roles/name/Test%20Role

Response:

<response status="success">
   <role type="role" href="/roles/id/531">
   <name type="string">Test Role</name>
   <id type="int">531</id>
   <node type="community"/>
   </role>
</response>