openreplay/ee/connectors/msgcodec/msgcodec.pyx
Delirium c7e5145282
feat(tracker): add beacon proxy and request body size (#1389)
* feat(tracker): add beacon proxy and body size

* feat(ui): remove unused components

* feat(ui): generate new messages, add body size to resource parser

* feat(ui): fix tooltip text, fix size detection (ts safe)

* feat(ui): cover resource with tests

* feat(ui): enable test coverage for player, utils and mstore

* fix(tracker): adjust test to support new message

* fix(tracker): fix tracker version for back compat

* feat(backend): added new column to network requests

* fix(tracker): fix unit tests

* fix(backend): fix msg gen

* fix(tracker): ci fun

* fix(tracker): changelog

* fix(tracker): fix some test

---------

Co-authored-by: Alexander Zavorotynskiy <zavorotynskiy@pm.me>
2023-10-17 12:25:20 +02:00

1009 lines
33 KiB
Cython

# Auto-generated, do not edit
from messages import *
#from io cimport BytesIO
from io import BytesIO
from libc.stdlib cimport abort
cdef extern from "Python.h":
int PyArg_ParseTupleAndKeywords(object args, object kwargs, char* format, char** keywords, ...)
cdef class PyMsg:
def __cinit__(self):
pass
ctypedef object PyBytesIO
cdef class MessageCodec:
"""
Implements encode/decode primitives
"""
cdef list msg_selector
def __init__(self, list msg_selector):
self.msg_selector = msg_selector
@staticmethod
cdef read_boolean(PyBytesIO reader):
cdef bint b
b = reader.read(1)[0]
return b == 1
@staticmethod
def read_bool_method(PyBytesIO reader):
return MessageCodec.read_boolean(reader)
@staticmethod
cdef read_uint(PyBytesIO reader):
cdef unsigned long x = 0 # the result
cdef unsigned int s = 0 # the shift (our result is big-ending)
cdef int i = 0 # n of byte (max 9 for uint64)
cdef bytes b
cdef unsigned long num
while True:
b = reader.read(1)
if len(b) == 0:
raise IndexError('bytes out of range')
num = int.from_bytes(b, "big", signed=False)
if num < 0x80:
if i > 9 or (i == 9 and num > 1):
raise OverflowError()
return int(x | num << s)
x |= (num & 0x7f) << s
s += 7
i += 1
@staticmethod
def read_size(PyBytesIO reader):
cdef unsigned long size = 0
cdef bytes b
cdef unsigned long num
for i in range(3):
b = reader.read(1)
num = int.from_bytes(b, "big", signed=False)
size += num << (8*i)
return size
@staticmethod
def read_int(PyBytesIO reader):
"""
ux, err := ReadUint(reader)
x := int64(ux >> 1)
if err != nil {
return x, err
}
if ux&1 != 0 {
x = ^x
}
return x, err
"""
cdef unsigned long ux = MessageCodec.read_uint(reader)
cdef long x = int(ux >> 1)
if ux & 1 != 0:
x = - x - 1
return x
@staticmethod
def read_string(PyBytesIO reader):
cdef unsigned long length = MessageCodec.read_uint(reader)
cdef bytes s
try:
s = reader.read(length)
except Exception as e:
print(f'Error while reading string of length {length}')
raise Exception(e)
try:
return s.decode("utf-8", errors="replace").replace("\x00", "\uFFFD")
except UnicodeDecodeError:
return None
@staticmethod
def read_message_id(PyBytesIO reader):
"""
Read and return the first byte where the message id is encoded
"""
cdef unsigned long id_ = MessageCodec.read_uint(reader)
return id_
@staticmethod
def encode(PyMsg m):
...
@staticmethod
def decode(bytes b):
cdef PyBytesIO reader = BytesIO(b)
return MessageCodec.read_head_message(reader)
@staticmethod
def check_message_id(bytes b):
"""
todo: make it static and without reader. It's just the first byte
Read and return the first byte where the message id is encoded
"""
cdef PyBytesIO reader = BytesIO(b)
cdef unsigned long id_ = MessageCodec.read_uint(reader)
return id_
@staticmethod
def decode_key(bytes b):
"""
Decode the message key (encoded with little endian)
"""
cdef unsigned long decoded
try:
decoded = int.from_bytes(b, "little", signed=False)
except Exception as e:
print(f"Error while decoding message key (SessionID) from {b}")
raise e
return decoded
def decode_detailed(self, bytes b):
cdef PyBytesIO reader = BytesIO(b)
cdef list messages_list
cdef int mode
try:
messages_list = [self.handler(reader, 0)]
except IndexError:
print('[WARN] Broken batch')
return list()
if isinstance(messages_list[0], BatchMeta):
# Old BatchMeta
mode = 0
elif isinstance(messages_list[0], BatchMetadata):
# New BatchMeta
if messages_list[0].version == 0:
mode = 0
else:
mode = 1
else:
return messages_list
while True:
try:
msg_decoded = self.handler(reader, mode)
if msg_decoded is not None:
messages_list.append(msg_decoded)
except IndexError:
break
return messages_list
def handler(self, PyBytesIO reader, int mode = 0):
cdef unsigned long message_id = MessageCodec.read_message_id(reader)
cdef int r_size
if mode == 1:
# We read the three bytes representing the length of message. It can be used to skip unwanted messages
r_size = MessageCodec.read_size(reader)
if message_id not in self.msg_selector:
reader.read(r_size)
return None
return MessageCodec.read_head_message(reader, message_id)
elif mode == 0:
# Old format with no bytes for message length
return MessageCodec.read_head_message(reader, message_id)
else:
raise IOError()
@staticmethod
def read_head_message(PyBytesIO reader, unsigned long message_id):
if message_id == 0:
return Timestamp(
timestamp=self.read_uint(reader)
)
if message_id == 1:
return SessionStart(
timestamp=self.read_uint(reader),
project_id=self.read_uint(reader),
tracker_version=self.read_string(reader),
rev_id=self.read_string(reader),
user_uuid=self.read_string(reader),
user_agent=self.read_string(reader),
user_os=self.read_string(reader),
user_os_version=self.read_string(reader),
user_browser=self.read_string(reader),
user_browser_version=self.read_string(reader),
user_device=self.read_string(reader),
user_device_type=self.read_string(reader),
user_device_memory_size=self.read_uint(reader),
user_device_heap_size=self.read_uint(reader),
user_country=self.read_string(reader),
user_id=self.read_string(reader)
)
if message_id == 3:
return SessionEndDeprecated(
timestamp=self.read_uint(reader)
)
if message_id == 4:
return SetPageLocation(
url=self.read_string(reader),
referrer=self.read_string(reader),
navigation_start=self.read_uint(reader)
)
if message_id == 5:
return SetViewportSize(
width=self.read_uint(reader),
height=self.read_uint(reader)
)
if message_id == 6:
return SetViewportScroll(
x=self.read_int(reader),
y=self.read_int(reader)
)
if message_id == 7:
return CreateDocument(
)
if message_id == 8:
return CreateElementNode(
id=self.read_uint(reader),
parent_id=self.read_uint(reader),
index=self.read_uint(reader),
tag=self.read_string(reader),
svg=self.read_boolean(reader)
)
if message_id == 9:
return CreateTextNode(
id=self.read_uint(reader),
parent_id=self.read_uint(reader),
index=self.read_uint(reader)
)
if message_id == 10:
return MoveNode(
id=self.read_uint(reader),
parent_id=self.read_uint(reader),
index=self.read_uint(reader)
)
if message_id == 11:
return RemoveNode(
id=self.read_uint(reader)
)
if message_id == 12:
return SetNodeAttribute(
id=self.read_uint(reader),
name=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 13:
return RemoveNodeAttribute(
id=self.read_uint(reader),
name=self.read_string(reader)
)
if message_id == 14:
return SetNodeData(
id=self.read_uint(reader),
data=self.read_string(reader)
)
if message_id == 15:
return SetCSSData(
id=self.read_uint(reader),
data=self.read_string(reader)
)
if message_id == 16:
return SetNodeScroll(
id=self.read_uint(reader),
x=self.read_int(reader),
y=self.read_int(reader)
)
if message_id == 17:
return SetInputTarget(
id=self.read_uint(reader),
label=self.read_string(reader)
)
if message_id == 18:
return SetInputValue(
id=self.read_uint(reader),
value=self.read_string(reader),
mask=self.read_int(reader)
)
if message_id == 19:
return SetInputChecked(
id=self.read_uint(reader),
checked=self.read_boolean(reader)
)
if message_id == 20:
return MouseMove(
x=self.read_uint(reader),
y=self.read_uint(reader)
)
if message_id == 21:
return NetworkRequestDeprecated(
type=self.read_string(reader),
method=self.read_string(reader),
url=self.read_string(reader),
request=self.read_string(reader),
response=self.read_string(reader),
status=self.read_uint(reader),
timestamp=self.read_uint(reader),
duration=self.read_uint(reader)
)
if message_id == 22:
return ConsoleLog(
level=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 23:
return PageLoadTiming(
request_start=self.read_uint(reader),
response_start=self.read_uint(reader),
response_end=self.read_uint(reader),
dom_content_loaded_event_start=self.read_uint(reader),
dom_content_loaded_event_end=self.read_uint(reader),
load_event_start=self.read_uint(reader),
load_event_end=self.read_uint(reader),
first_paint=self.read_uint(reader),
first_contentful_paint=self.read_uint(reader)
)
if message_id == 24:
return PageRenderTiming(
speed_index=self.read_uint(reader),
visually_complete=self.read_uint(reader),
time_to_interactive=self.read_uint(reader)
)
if message_id == 25:
return JSExceptionDeprecated(
name=self.read_string(reader),
message=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 26:
return IntegrationEvent(
timestamp=self.read_uint(reader),
source=self.read_string(reader),
name=self.read_string(reader),
message=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 27:
return CustomEvent(
name=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 28:
return UserID(
id=self.read_string(reader)
)
if message_id == 29:
return UserAnonymousID(
id=self.read_string(reader)
)
if message_id == 30:
return Metadata(
key=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 31:
return PageEvent(
message_id=self.read_uint(reader),
timestamp=self.read_uint(reader),
url=self.read_string(reader),
referrer=self.read_string(reader),
loaded=self.read_boolean(reader),
request_start=self.read_uint(reader),
response_start=self.read_uint(reader),
response_end=self.read_uint(reader),
dom_content_loaded_event_start=self.read_uint(reader),
dom_content_loaded_event_end=self.read_uint(reader),
load_event_start=self.read_uint(reader),
load_event_end=self.read_uint(reader),
first_paint=self.read_uint(reader),
first_contentful_paint=self.read_uint(reader),
speed_index=self.read_uint(reader),
visually_complete=self.read_uint(reader),
time_to_interactive=self.read_uint(reader)
)
if message_id == 32:
return InputEvent(
message_id=self.read_uint(reader),
timestamp=self.read_uint(reader),
value=self.read_string(reader),
value_masked=self.read_boolean(reader),
label=self.read_string(reader)
)
if message_id == 37:
return CSSInsertRule(
id=self.read_uint(reader),
rule=self.read_string(reader),
index=self.read_uint(reader)
)
if message_id == 38:
return CSSDeleteRule(
id=self.read_uint(reader),
index=self.read_uint(reader)
)
if message_id == 39:
return Fetch(
method=self.read_string(reader),
url=self.read_string(reader),
request=self.read_string(reader),
response=self.read_string(reader),
status=self.read_uint(reader),
timestamp=self.read_uint(reader),
duration=self.read_uint(reader)
)
if message_id == 40:
return Profiler(
name=self.read_string(reader),
duration=self.read_uint(reader),
args=self.read_string(reader),
result=self.read_string(reader)
)
if message_id == 41:
return OTable(
key=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 42:
return StateAction(
type=self.read_string(reader)
)
if message_id == 44:
return Redux(
action=self.read_string(reader),
state=self.read_string(reader),
duration=self.read_uint(reader)
)
if message_id == 45:
return Vuex(
mutation=self.read_string(reader),
state=self.read_string(reader)
)
if message_id == 46:
return MobX(
type=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 47:
return NgRx(
action=self.read_string(reader),
state=self.read_string(reader),
duration=self.read_uint(reader)
)
if message_id == 48:
return GraphQL(
operation_kind=self.read_string(reader),
operation_name=self.read_string(reader),
variables=self.read_string(reader),
response=self.read_string(reader)
)
if message_id == 49:
return PerformanceTrack(
frames=self.read_int(reader),
ticks=self.read_int(reader),
total_js_heap_size=self.read_uint(reader),
used_js_heap_size=self.read_uint(reader)
)
if message_id == 50:
return StringDict(
key=self.read_uint(reader),
value=self.read_string(reader)
)
if message_id == 51:
return SetNodeAttributeDict(
id=self.read_uint(reader),
name_key=self.read_uint(reader),
value_key=self.read_uint(reader)
)
if message_id == 53:
return ResourceTimingDeprecated(
timestamp=self.read_uint(reader),
duration=self.read_uint(reader),
ttfb=self.read_uint(reader),
header_size=self.read_uint(reader),
encoded_body_size=self.read_uint(reader),
decoded_body_size=self.read_uint(reader),
url=self.read_string(reader),
initiator=self.read_string(reader)
)
if message_id == 54:
return ConnectionInformation(
downlink=self.read_uint(reader),
type=self.read_string(reader)
)
if message_id == 55:
return SetPageVisibility(
hidden=self.read_boolean(reader)
)
if message_id == 56:
return PerformanceTrackAggr(
timestamp_start=self.read_uint(reader),
timestamp_end=self.read_uint(reader),
min_fps=self.read_uint(reader),
avg_fps=self.read_uint(reader),
max_fps=self.read_uint(reader),
min_cpu=self.read_uint(reader),
avg_cpu=self.read_uint(reader),
max_cpu=self.read_uint(reader),
min_total_js_heap_size=self.read_uint(reader),
avg_total_js_heap_size=self.read_uint(reader),
max_total_js_heap_size=self.read_uint(reader),
min_used_js_heap_size=self.read_uint(reader),
avg_used_js_heap_size=self.read_uint(reader),
max_used_js_heap_size=self.read_uint(reader)
)
if message_id == 57:
return LoadFontFace(
parent_id=self.read_uint(reader),
family=self.read_string(reader),
source=self.read_string(reader),
descriptors=self.read_string(reader)
)
if message_id == 58:
return SetNodeFocus(
id=self.read_int(reader)
)
if message_id == 59:
return LongTask(
timestamp=self.read_uint(reader),
duration=self.read_uint(reader),
context=self.read_uint(reader),
container_type=self.read_uint(reader),
container_src=self.read_string(reader),
container_id=self.read_string(reader),
container_name=self.read_string(reader)
)
if message_id == 60:
return SetNodeAttributeURLBased(
id=self.read_uint(reader),
name=self.read_string(reader),
value=self.read_string(reader),
base_url=self.read_string(reader)
)
if message_id == 61:
return SetCSSDataURLBased(
id=self.read_uint(reader),
data=self.read_string(reader),
base_url=self.read_string(reader)
)
if message_id == 62:
return IssueEventDeprecated(
message_id=self.read_uint(reader),
timestamp=self.read_uint(reader),
type=self.read_string(reader),
context_string=self.read_string(reader),
context=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 63:
return TechnicalInfo(
type=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 64:
return CustomIssue(
name=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 66:
return AssetCache(
url=self.read_string(reader)
)
if message_id == 67:
return CSSInsertRuleURLBased(
id=self.read_uint(reader),
rule=self.read_string(reader),
index=self.read_uint(reader),
base_url=self.read_string(reader)
)
if message_id == 69:
return MouseClick(
id=self.read_uint(reader),
hesitation_time=self.read_uint(reader),
label=self.read_string(reader),
selector=self.read_string(reader)
)
if message_id == 70:
return CreateIFrameDocument(
frame_id=self.read_uint(reader),
id=self.read_uint(reader)
)
if message_id == 71:
return AdoptedSSReplaceURLBased(
sheet_id=self.read_uint(reader),
text=self.read_string(reader),
base_url=self.read_string(reader)
)
if message_id == 72:
return AdoptedSSReplace(
sheet_id=self.read_uint(reader),
text=self.read_string(reader)
)
if message_id == 73:
return AdoptedSSInsertRuleURLBased(
sheet_id=self.read_uint(reader),
rule=self.read_string(reader),
index=self.read_uint(reader),
base_url=self.read_string(reader)
)
if message_id == 74:
return AdoptedSSInsertRule(
sheet_id=self.read_uint(reader),
rule=self.read_string(reader),
index=self.read_uint(reader)
)
if message_id == 75:
return AdoptedSSDeleteRule(
sheet_id=self.read_uint(reader),
index=self.read_uint(reader)
)
if message_id == 76:
return AdoptedSSAddOwner(
sheet_id=self.read_uint(reader),
id=self.read_uint(reader)
)
if message_id == 77:
return AdoptedSSRemoveOwner(
sheet_id=self.read_uint(reader),
id=self.read_uint(reader)
)
if message_id == 78:
return JSException(
name=self.read_string(reader),
message=self.read_string(reader),
payload=self.read_string(reader),
metadata=self.read_string(reader)
)
if message_id == 79:
return Zustand(
mutation=self.read_string(reader),
state=self.read_string(reader)
)
if message_id == 80:
return BatchMeta(
page_no=self.read_uint(reader),
first_index=self.read_uint(reader),
timestamp=self.read_int(reader)
)
if message_id == 81:
return BatchMetadata(
version=self.read_uint(reader),
page_no=self.read_uint(reader),
first_index=self.read_uint(reader),
timestamp=self.read_int(reader),
location=self.read_string(reader)
)
if message_id == 82:
return PartitionedMessage(
part_no=self.read_uint(reader),
part_total=self.read_uint(reader)
)
if message_id == 83:
return NetworkRequest(
type=self.read_string(reader),
method=self.read_string(reader),
url=self.read_string(reader),
request=self.read_string(reader),
response=self.read_string(reader),
status=self.read_uint(reader),
timestamp=self.read_uint(reader),
duration=self.read_uint(reader),
transferred_body_size=self.read_uint(reader)
)
if message_id == 112:
return InputChange(
id=self.read_uint(reader),
value=self.read_string(reader),
value_masked=self.read_boolean(reader),
label=self.read_string(reader),
hesitation_time=self.read_int(reader),
input_duration=self.read_int(reader)
)
if message_id == 113:
return SelectionChange(
selection_start=self.read_uint(reader),
selection_end=self.read_uint(reader),
selection=self.read_string(reader)
)
if message_id == 114:
return MouseThrashing(
timestamp=self.read_uint(reader)
)
if message_id == 115:
return UnbindNodes(
total_removed_percent=self.read_uint(reader)
)
if message_id == 116:
return ResourceTiming(
timestamp=self.read_uint(reader),
duration=self.read_uint(reader),
ttfb=self.read_uint(reader),
header_size=self.read_uint(reader),
encoded_body_size=self.read_uint(reader),
decoded_body_size=self.read_uint(reader),
url=self.read_string(reader),
initiator=self.read_string(reader),
transferred_size=self.read_uint(reader),
cached=self.read_boolean(reader)
)
if message_id == 117:
return TabChange(
tab_id=self.read_string(reader)
)
if message_id == 118:
return TabData(
tab_id=self.read_string(reader)
)
if message_id == 125:
return IssueEvent(
message_id=self.read_uint(reader),
timestamp=self.read_uint(reader),
type=self.read_string(reader),
context_string=self.read_string(reader),
context=self.read_string(reader),
payload=self.read_string(reader),
url=self.read_string(reader)
)
if message_id == 126:
return SessionEnd(
timestamp=self.read_uint(reader),
encryption_key=self.read_string(reader)
)
if message_id == 127:
return SessionSearch(
timestamp=self.read_uint(reader),
partition=self.read_uint(reader)
)
if message_id == 90:
return IOSSessionStart(
timestamp=self.read_uint(reader),
project_id=self.read_uint(reader),
tracker_version=self.read_string(reader),
rev_id=self.read_string(reader),
user_uuid=self.read_string(reader),
user_os=self.read_string(reader),
user_os_version=self.read_string(reader),
user_device=self.read_string(reader),
user_device_type=self.read_string(reader),
user_country=self.read_string(reader)
)
if message_id == 91:
return IOSSessionEnd(
timestamp=self.read_uint(reader)
)
if message_id == 92:
return IOSMetadata(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
key=self.read_string(reader),
value=self.read_string(reader)
)
if message_id == 93:
return IOSCustomEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
name=self.read_string(reader),
payload=self.read_string(reader)
)
if message_id == 94:
return IOSUserID(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
value=self.read_string(reader)
)
if message_id == 95:
return IOSUserAnonymousID(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
value=self.read_string(reader)
)
if message_id == 96:
return IOSScreenChanges(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
x=self.read_uint(reader),
y=self.read_uint(reader),
width=self.read_uint(reader),
height=self.read_uint(reader)
)
if message_id == 97:
return IOSCrash(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
name=self.read_string(reader),
reason=self.read_string(reader),
stacktrace=self.read_string(reader)
)
if message_id == 98:
return IOSViewComponentEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
screen_name=self.read_string(reader),
view_name=self.read_string(reader),
visible=self.read_boolean(reader)
)
if message_id == 100:
return IOSClickEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
label=self.read_string(reader),
x=self.read_uint(reader),
y=self.read_uint(reader)
)
if message_id == 101:
return IOSInputEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
value=self.read_string(reader),
value_masked=self.read_boolean(reader),
label=self.read_string(reader)
)
if message_id == 102:
return IOSPerformanceEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
name=self.read_string(reader),
value=self.read_uint(reader)
)
if message_id == 103:
return IOSLog(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
severity=self.read_string(reader),
content=self.read_string(reader)
)
if message_id == 104:
return IOSInternalError(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
content=self.read_string(reader)
)
if message_id == 105:
return IOSNetworkCall(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
type=self.read_string(reader),
method=self.read_string(reader),
url=self.read_string(reader),
request=self.read_string(reader),
response=self.read_string(reader),
status=self.read_uint(reader),
duration=self.read_uint(reader)
)
if message_id == 106:
return IOSSwipeEvent(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
label=self.read_string(reader),
x=self.read_uint(reader),
y=self.read_uint(reader),
direction=self.read_string(reader)
)
if message_id == 107:
return IOSBatchMeta(
timestamp=self.read_uint(reader),
length=self.read_uint(reader),
first_index=self.read_uint(reader)
)
if message_id == 110:
return IOSPerformanceAggregated(
timestamp_start=self.read_uint(reader),
timestamp_end=self.read_uint(reader),
min_fps=self.read_uint(reader),
avg_fps=self.read_uint(reader),
max_fps=self.read_uint(reader),
min_cpu=self.read_uint(reader),
avg_cpu=self.read_uint(reader),
max_cpu=self.read_uint(reader),
min_memory=self.read_uint(reader),
avg_memory=self.read_uint(reader),
max_memory=self.read_uint(reader),
min_battery=self.read_uint(reader),
avg_battery=self.read_uint(reader),
max_battery=self.read_uint(reader)
)
if message_id == 111:
return IOSIssueEvent(
timestamp=self.read_uint(reader),
type=self.read_string(reader),
context_string=self.read_string(reader),
context=self.read_string(reader),
payload=self.read_string(reader)
)