1:- module(lsp_parser, [lsp_request//1]).

    9:- use_module(library(assoc), [list_to_assoc/2, get_assoc/3]).   10:- use_module(library(codesio), [open_codes_stream/2]).   11:- use_module(library(dcg/basics), [string_without//2]).   12:- use_module(library(http/json), [json_read_dict/3]).   13
   14header(Key-Value) -->
   15    string_without(":", KeyC), ": ", string_without("\r", ValueC),
   16    { string_codes(Key, KeyC), string_codes(Value, ValueC) }.
   17
   18headers([Header]) -->
   19    header(Header), "\r\n\r\n", !.
   20headers([Header|Headers]) -->
   21    header(Header), "\r\n",
   22    headers(Headers).

 lsp_request(-Req)// is det

A DCG nonterminal describing an HTTP request. Currently can only parse the request from a list of codes.

The HTTP headers are parsed into an assoc tree which maps strings to strings. The body of the request is parsed into a dict according to json_read_dict/3. The headers list must include a Content-Length header.

?- phrase(lsp_request(Req), `Content-Length: 7\r\n\r\n{"x":1}`).
Req = _{body:_{x:1}, headers:t("Content-Length", "7", -, t, t)}.

Arguments:

Req	- a dict containing keys headers and body

   40lsp_request(_{headers: Headers, body: Body}) -->
   41    headers(HeadersList),
   42    { list_to_assoc(HeadersList, Headers),
   43      get_assoc("Content-Length", Headers, LengthS),
   44      number_string(Length, LengthS),
   45      length(JsonCodes, Length) },
   46    JsonCodes,
   47    { ground(JsonCodes),
   48      open_codes_stream(JsonCodes, JsonStream),
   49      json_read_dict(JsonStream, Body, []) }