Add Global context fields to StdlibFormatter (#65)

* Resolves #57 See: #57 * Update _stdlib.py Updated the type hints. * Fix lint (mypy and line length) * Update _stdlib.py * Update _stdlib.py Co-authored-by: Difrango, Ronald <ronald.difrango@fmr.com> Co-authored-by: Colton Myers <colton.myers@gmail.com>

Author: rdifrango

ecs_logging/_stdlib.py

@@ -72,15 +72,16 @@ class StdlibFormatter(logging.Formatter):
  converter = time.gmtime
 
  def __init__(
- self,
- fmt=None,
- datefmt=None,
- style="%",
- validate=None,
- stack_trace_limit=None,
- exclude_fields=(),
+ self, # type: Any
+ fmt=None, # type: Optional[str]
+ datefmt=None, # type: Optional[str]
+ style="%", # type: str
+ validate=None, # type: Optional[bool]
+ stack_trace_limit=None, # type: Optional[int]
+ extra=None, # type: Optional[Dict[str, Any]]
+ exclude_fields=(), # type: Sequence[str]
  ):
- # type: (Any, Optional[str], Optional[str], str, Optional[bool], Optional[int], Sequence[str]) -> None
+ # type: (...) -> None
  """Initialize the ECS formatter.
 
  :param int stack_trace_limit:
@@ -89,6 +90,8 @@ def __init__(
  Setting this to zero will suppress stack traces.
  This setting doesn't affect ``LogRecord.stack_info`` because
  this attribute is typically already pre-formatted.
+ :param Optional[Dict[str, Any]] extra:
+ Specifies the collection of meta-data fields to add to all records.
  :param Sequence[str] exclude_fields:
  Specifies any fields that should be suppressed from the resulting
  fields, expressed with dot notation::
@@ -129,6 +132,7 @@ def __init__(
  ):
  raise TypeError("'exclude_fields' must be a sequence of strings")
 
+ self._extra = extra
  self._exclude_fields = frozenset(exclude_fields)
  self._stack_trace_limit = stack_trace_limit
 
@@ -218,6 +222,10 @@ def format_to_ecs(self, record):
  # since they can be defined as 'extras={"http": {"method": "GET"}}'
  extra_keys = set(available).difference(self._LOGRECORD_DICT)
  extras = flatten_dict({key: available[key] for key in extra_keys})
+ # Merge in any global extra's
+ if self._extra is not None:
+ for field, value in self._extra.items():
+ merge_dicts(de_dot(field, value), extras)
 
  # Pop all Elastic APM extras and add them
  # to standard tracing ECS fields.

tests/test_stdlib_formatter.py

@@ -26,7 +26,6 @@
 import ecs_logging
 from .compat import StringIO
 
-
 requires_py3 = pytest.mark.skipif(
  sys.version_info[0] < 3, reason="Test requires Python 3.x+"
 )
@@ -63,6 +62,19 @@ def test_record_formatted(spec_validator):
  )
 
 
+def test_extra_global_is_merged(spec_validator):
+ formatter = ecs_logging.StdlibFormatter(
+ exclude_fields=["process"], extra={"environment": "dev"}
+ )
+
+ assert spec_validator(formatter.format(make_record())) == (
+ '{"@timestamp":"2020-03-20T14:12:46.123Z","log.level":"debug","message":"1: hello","ecs":{"version":"1.6.0"},'
+ '"environment":"dev",'
+ '"log":{"logger":"logger-name","origin":{"file":{"line":10,"name":"file.py"},"function":"test_function"},'
+ '"original":"1: hello"}}'
+ )
+
+
 def test_can_be_overridden(spec_validator):
  class CustomFormatter(ecs_logging.StdlibFormatter):
  def format_to_ecs(self, record):