metric element

class metrix.element.MElement(name: str, value: Union[int, float], *, tags: Optional[Dict] = None)

An individual metric element – a single data point – to be sent through a stream and on to one or more sinks.

>>> from metrix import MElement
>>> me = MElement("counts", 1, tags={"env": "dev", "foo": "bar"})
>>> print(me)
MElement(name='counts', value=1, tags={'env': 'dev', 'foo': 'bar'})
>>> me.key
'env:dev|foo:bar'

Parameters

• name – Base name of the metric to which the element belongs.

• value – Numeric value of the metric element.

• tags – Optional tags to associate with this (name, value) pair.

Note

In typical usage, users will not directly instantiate this class; instead, they’ll pass (name, value, tags) into MCoordinator.send() or MCoordinator.timer(), which will create a corresponding MElement under the hood.

metrix.element.key_from_tags(tags: Optional[Dict]) → Optional[str]

Generate a (hashable!) key string from a collection of tags, where tags are pipe-delimited and each tag’s field and value are colon-delimited.

>>> key_from_tags({"foo": "bar})
"foo:bar"
>>> key_from_tags({"foo": "bar", "bat": "baz"})
"bat:baz|foo:bar"

Note

The ordering of items in tags doesn’t matter, since the generated key is always ordered alphabetically.

metrix.element.tags_from_key(key: Optional[str]) → Optional[Dict]

Generate a collection of tags from a key string, where tags are pipe-delimited and each tag’s field and value are colon-delimited.

>>> tags_from_key(None)
None
>>> tags_from_key("foo:bar")
{"foo": "bar"}
>>> tags_from_key("foo:bar|bat:baz")
{"bat": "baz", "foo": "bar"}

Note

The ordering of items in key doesn’t matter, since the generated tags items are always ordered alphabetically.

See also

key_from_tags()