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StreamSet

pingthings.timeseries.client.StreamSet

StreamSet(streams: list[Stream] = [])

A collection of Stream objects.

Create a collection of stream objects.

Methods:

Name Description
count

Get the total count of raw measurements that are present in each stream.

earliest

Find the earliest point (in time) that is present in the streams.

filter

Create a new StreamSet that is a subset of the streams based on metadata filtering.

flush

Force a flush of the buffered data to persistent storage for all streams.

get_latest_version

Get the latest version of each stream.

get_version_at_time

Get the version of each stream at time realtime.

insert

Insert new timeseries data into the streams.

latest

Find the latest point (in time) that is present in the streams.

pin_versions

Pin the versions of all streams to specific values.

raw_values

Return the raw time,value pairs of data from the streams.

refresh_metadata

Update all metadata for each stream in the StreamSet

windowed_values

Return statistical summaries of the data.

Functions

count

Get the total count of raw measurements that are present in each stream.

Parameters:

Name Type Description Default
start
Optional[int | datetime | Timestamp]

Bound the lower end of this query by a start time, by default MINIMUM_TIME.

MINIMUM_TIME
end
Optional[int | datetime | Timestamp]

Bound the upper end of this query by an end time, by default MAXIMUM_TIME

MAXIMUM_TIME
versions
Optional[int | dict[UUID, int]]

Versions of the streams to query against, by default None, which means a version of 0 is used.

None
precise
bool

Do we need an exact count or is an estimate reasonable, by default False

False

Returns:

Type Description
dict[UUID, Optional[int]]

Mapping of individual stream.uuid's to count values.

earliest

earliest() -> dict[UUID, Optional[Point]]

Find the earliest point (in time) that is present in the streams.

Returns:

Type Description
dict[UUID, Optional[Point]]

The earliest points in the streams.

filter

filter(
    collection: Optional[str] = None,
    tags: Optional[dict[str, str]] = None,
    annotations: Optional[dict[str, str]] = None,
    refresh_metadata: bool = True,
) -> Optional[StreamSet]

Create a new StreamSet that is a subset of the streams based on metadata filtering.

Parameters:

Name Type Description Default
collection
Optional[str]

The collection string to filter by, by default None

None
tags
Optional[dict[str, str]]

Tag metadata to filter on, by default None

None
annotations
Optional[dict[str, str]]

Annotation metadata to filter on, by default None

None
refresh_metadata
bool

Should we use the latest metadata of the streams to filter on, by default True

True

Returns:

Type Description
Optional[StreamSet]

A subset of the streams that match the provided filters, if any.

flush

flush() -> dict[UUID, int]

Force a flush of the buffered data to persistent storage for all streams.

If data was present, the version number will be positively incremented.

Returns:

Type Description
dict[UUID, int]

The version number of each stream after the flush as a uuid:version dictionary mapping.

get_latest_version

get_latest_version() -> dict[UUID, int]

Get the latest version of each stream.

Returns:

Type Description
dict[UUID, int]

A stream.uuid, latest version mapping.

get_version_at_time

get_version_at_time(
    realtime: int | datetime,
) -> dict[UUID, int]

Get the version of each stream at time realtime.

Parameters:

Name Type Description Default
realtime
int | datetime

The time to check the stream version against

required

Returns:

Type Description
dict[UUID, int]

A stream.uuid, version mapping.

insert

insert(
    data_map: dict[UUID, Table],
    merge_policy: MergePolicy = "replace",
) -> dict[UUID, int]

Insert new timeseries data into the streams.

Default merge policy has changed!

Starting with the new pingthings api, the default merge policy is now replace. Please refer to the merge policy docs

Data must follow a specific schema for insertion

Your data pyarrow table or record batch must have a schema that matches the TIME_VALUE_F64_SCHEMA, defined. Order of the columns matter.

Parameters:

Name Type Description Default
data_map
dict[UUID, Table]

A mapping of stream.uuid to pyarrow.Table timeseries data.

required
merge_policy
MergePolicy

How to handle when duplicate timestamp points are inserted into the stream

'replace'

Returns:

Type Description
dict[UUID, int]

A mapping of stream.uuid, version of the stream after insertion.

latest

latest() -> dict[UUID, Optional[Point]]

Find the latest point (in time) that is present in the streams.

Returns:

Type Description
dict[UUID, Optional[Point]]

The latest point in the streams, if present.

pin_versions

pin_versions(versions: Optional[list[int]] = None) -> None

Pin the versions of all streams to specific values.

raw_values

raw_values(
    start: int | datetime | Timestamp,
    end: int | datetime | Timestamp,
    snap_period: Optional[int | timedelta | Timedelta] = 0,
    versions: Optional[list[int]] = None,
    schema: Optional[Schema] = None,
) -> Table

Return the raw time,value pairs of data from the streams.

StreamSet raw value queries de-duplicate timestamps

Current behavior for the accelerated "multistream" streamset queries de-duplicates timestamps internally.

Parameters:

Name Type Description Default
start
int | datetime | Timestamp

Start time to get data (inclusive)

required
end
int | datetime | Timestamp

End time for the data query (exclusive)

required
snap_period
Optional[int | timedelta | Timedelta]

What period of time (if any) should the data be aligned to?

0
versions
Optional[list[int]]

What versions of the streams to query against, using the default of None will use version 0.

None
schema
Optional[Schema]

What pyarrow.Schema should the time,values be returned as, default will be the server default.

None

Returns:

Type Description
Table

A table of timeseries data in the interval of [start, end)

refresh_metadata

refresh_metadata() -> None

Update all metadata for each stream in the StreamSet

windowed_values

windowed_values(
    start: int | datetime | Timestamp,
    end: int | datetime | Timestamp,
    width: int | timedelta | Timedelta | _PW,
    precise: Optional[bool] = False,
    versions: Optional[list[int]] = None,
    schema: Optional[Schema] = STAT_F32_SCHEMA,
) -> Table

Return statistical summaries of the data.

Parameters:

Name Type Description Default
start
int | datetime | Timestamp

The approximate start time to get data (inclusive). See notes.

required
end
int | datetime | Timestamp

The approximate end time for the data query (exclusive). See notes.

required
width
int | timedelta | Timedelta | _PW

The approximate size of statistical windows to return, will contain summaries of the data between start to end of size width.

required
precise
Optional[bool]

Pass in precise=True to use the exact start, end and width values specified. See notes.

False
versions
Optional[list[int]]

What versions of the stream to query against, using the default of None will use version 0.

None
schema
Optional[Schema]

What pyarrow.Schema should the time,statistical summary timeseries be returned as, default will be the server default.

STAT_F32_SCHEMA

Returns:

Type Description
Table

The statistical summary information of the stream as a timeseries.

Notes

By default (precise=False), the values provided to start, end and width may not fully align with the values actually used by the query. Instead, the window width used will be the largest power of 2 ns that is smaller than the provided window. Doing so aligns the query with BTrDB's internal tree structure and thus increases query performance by several orders of magnitude.

Consequently, the actual time-range of the data pulled will be the aligned values that fall within the range \([start, end)\).