send server requests to stream (#918)

* send server requests to stream
* comment out method not found

Author: prabirshrestha

autoload/lsp.vim

@@ -760,15 +760,22 @@ endfunction
 
 function! s:on_request(server_name, id, request) abort
     call lsp#log_verbose('<---', a:id, a:request)
+
+    let l:stream_data = { 'server': a:server_name, 'request': a:request }
+    call s:Stream(1, l:stream_data) " notify stream before callbacks
+
     if a:request['method'] ==# 'workspace/applyEdit'
         call lsp#utils#workspace_edit#apply_workspace_edit(a:request['params']['edit'])
         call s:send_response(a:server_name, { 'id': a:request['id'], 'result': { 'applied': v:true } })
     elseif a:request['method'] ==# 'workspace/configuration'
         let l:response_items = map(a:request['params']['items'], { key, val -> lsp#utils#workspace_config#get_value(a:server_name, val) })
         call s:send_response(a:server_name, { 'id': a:request['id'], 'result': l:response_items })
     else
-        " Error returned according to json-rpc specification.
-        call s:send_response(a:server_name, { 'id': a:request['id'], 'error': { 'code': -32601, 'message': 'Method not found' } })
+        " TODO: for now comment this out until we figure out a better solution.
+        " We need to comment this out so that others outside of vim-lsp can
+        " hook into the stream and provide their own response.
+        " " Error returned according to json-rpc specification.
+        " call s:send_response(a:server_name, { 'id': a:request['id'], 'error': { 'code': -32601, 'message': 'Method not found' } })
     endif
 endfunction