ocaml-cohttp: add initial version (0.17.1) to the system

pkgs/development/ocaml-modules/cohttp/default.nix

@@ -0,0 +1,29 @@
+{stdenv, buildOcaml, fetchurl, cmdliner, re, uri, fieldslib, sexplib, conduit,
+ stringext, base64, magic-mime, ounit, alcotest, lwt ? null,
+ async ? null, async_ssl ? null}:
+
+buildOcaml rec {
+  name = "cohttp";
+  version = "0.17.1";
+
+  minimumSupportedOcamlVersion = "4.02";
+
+  src = fetchurl {
+    url = "https://github.com/mirage/ocaml-cohttp/archive/v${version}.tar.gz";
+    sha256 = "fb124fb2fb5ff2e74559bf380627f6a537e208c1518ddcb01f0d37b62b55f673";
+  };
+
+  buildInputs = [ alcotest ];
+  propagatedBuildInputs = [ cmdliner re uri fieldslib sexplib sexplib
+                            conduit stringext base64 magic-mime ounit async
+                            async_ssl lwt ];
+
+  buildFlags = "PREFIX=$(out)";
+
+  meta = with stdenv.lib; {
+    homepage = https://github.com/mirage/ocaml-cohttp;
+    description = "Very lightweight HTTP server using Lwt or Async";
+    license = licenses.mit;
+    maintainers = [ maintainers.ericbmerritt ];
+  };
+}

pkgs/top-level/all-packages.nix

@@ -4126,6 +4126,10 @@ let
 
     cmdliner = callPackage ../development/ocaml-modules/cmdliner { };
 
+    cohttp = callPackage ../development/ocaml-modules/cohttp {
+      lwt = ocaml_lwt;
+    };
+
     config-file = callPackage ../development/ocaml-modules/config-file { };
 
     cpdf = callPackage ../development/ocaml-modules/cpdf { };