http_client: content-type fixes

src/http_client.nim

@@ -26,9 +26,30 @@ proc url(req: HttpRequest): Uri =
       elif i < vals.high: result.query.add ','
       result.query.add val.string.encodeUrl
 
-proc bodyString(req: HttpRequest): string =
-  if req.body.orKind == RequestBodyKind.present:
-    return cast[string](req.body.present)
+proc toContent(body: Value; contentType: var string): string =
+  case contentType
+  of "application/json":
+    var stream = newStringStream()
+    writeText(stream, body, textJson)
+    return stream.data.move
+  of "application/preserves":
+    return cast[string](body.encode)
+  of "text/preserves":
+    return $body
+  else:
+    discard
+
+  case body.kind
+  of pkString:
+    result = body.string
+    if contentType == "":
+      contentType = "text/plain"
+  of pkByteString:
+    result = cast[string](body.bytes)
+    if contentType == "":
+      contentType = "application/octet-stream"
+  else:
+    raise newException(ValueError, "unknown content type")
 
 proc spawnHttpClient*(turn: Turn; root: Cap): Actor {.discardable.} =
 
@@ -42,14 +63,15 @@ proc spawnHttpClient*(turn: Turn; root: Cap): Actor {.discardable.} =
             headers = newHttpHeaders()
             contentType = ""
           for key, val in ctx.req.headers:
-            if key == Symbol"Content-Type":
+            if key == Symbol"content-type":
               contentType = val
             client.headers[key.string] = val
           let stdRes = client.request(
               ctx.req.url,
               ctx.req.method.string.toUpper,
-              ctx.req.bodyString, headers
+              ctx.req.body.toContent(contentType), headers
             )
+          client.headers["content-type"] = contentType
           var resp = HttpResponse(orKind: HttpResponseKind.status)
           resp.status.code = stdRes.status[0 .. 2].parseInt
           resp.status.message = stdRes.status[3 .. ^1]