Improve event data handling

It looks like the first two characters after the ContentLength is
specified are a carriage return. This has thrown off the json string
parsing leading to hand rolling regex which fails in odd ways (see #204).
Now, pull out a couple extra characters to get past this leading
carriage return. If the leading characters are not there, we should have
a trailing \r\n\r\n which is safe to add, and will just be stripped out.
With this change in place, we are able to use json parsing on data, with
a fallback to sending the data string.

src/amcrest/event.py

@@ -8,6 +8,7 @@
 # GNU General Public License for more details.
 #
 # vim:sw=4:ts=4:et
+import json
 import logging
 import re
 from typing import (
@@ -31,9 +32,6 @@
 
 _LOGGER = logging.getLogger(__name__)
 _REG_PARSE_KEY_VALUE = re.compile(r"(?P<key>.+?)(?:=)(?P<value>.+?)(?:;|$)")
-_REG_PARSE_MALFORMED_JSON = re.compile(
- r'(?P<key>"[^"\\]*(?:\\.[^"\\]*)*"|[^\s"]+)\s:\s(?P<value>"[^"\\]*(?:\\.[^"\\]*)*"|[^\s"]+)'
-)
 
 
 def _event_lines(ret: Iterable[str]) -> Iterator[str]:
@@ -54,6 +52,14 @@ async def _async_event_lines(ret: AsyncIterable[str]) -> AsyncIterator[str]:
  line.clear()
 
 
+async def _async_event_info(ret: AsyncIterable[str], length: int) -> str:
+ line = []
+ async for char in ret:
+ line.append(char)
+ if len(line) == length:
+ return "".join(line)
+
+
 class Event(Http):
  def event_handler_config(self, handlername: str) -> str:
  return self._get_config(handlername)
@@ -304,7 +310,10 @@ def event_stream(
  try:
  for line in _event_lines(ret.iter_content(decode_unicode=True)):
  if line.lower().startswith("content-length:"):
- chunk_size = int(line.split(":")[1])
+ # There tends to be a leading \r\n, so add 2 to the length.
+ # If this is not present, there is a trailing \r\n\r\n at
+ # the end that will just be stripped out
+ chunk_size = int(line.split(":")[1]) + 2
  try:
  yield next(
  ret.iter_content(
@@ -332,16 +341,12 @@ async def async_event_stream(
  it = ret.aiter_text(chunk_size=1)
  async for line in _async_event_lines(it):
  if line.lower().startswith("content-length:"):
- chunk_size = int(line.split(":")[1])
- chars = []
- async for char in it:
- chars.append(char)
- if len(chars) == chunk_size:
- break
- else:
- # If we can't get the chunk, then return out
- return
- yield "".join(chars)
+ # There tends to be a leading \r\n, so add 2 to the
+ # length. If this is not present, there is a
+ # trailing \r\n\r\n at the end that will just be
+ # stripped out
+ chunk_size = int(line.split(":")[1]) + 2
+ yield await _async_event_info(it, chunk_size)
  except ReadTimeoutError:
  continue
 
@@ -375,12 +380,10 @@ def _build_payload(self, event_info: str) -> Dict[str, Any]:
  event_info.strip().replace("\n", "")
  ):
  if key == "data":
- value = {
- data_key.replace('"', ""): data_value.replace('"', "")
- for data_key, data_value in _REG_PARSE_MALFORMED_JSON.findall(
- value
- )
- }
+ try:
+ value = json.loads(value)
+ except json.JSONDecodeError:
+ pass
  payload[key] = value
  _LOGGER.debug(
  "%s generate new event, code: %s , payload: %s",