Databroker¶

Deprecation Notice¶

Databroker is no longer recommended for new users or facilities adopting Bluesky. Instead, Tiled with Bluesky Tiled Plugins is recommended as the canonical way to persist and access data and metadata from Bluesky.

Databroker now serves two purposes that remain relevant for some users and some faciilities. First, it contains code adapting the legacy MongoDB-based Bluesky document storage to Tiled—effectively a server-side plugin for Tiled. Second, it wraps the Tiled Python client to provide an API backward-compatible with legacy Databroker user code. _If you do not have MongoDB-based Bluesky storage and you do not have legacy Databroker user code, you do not need Databroker._

Databroker will be maintained by NSLS-II through April 2027 at minimum to support the transition from MongoDB-based document storage to PostgreSQL-based storage. The Python user interface may be maintained longer still, depending on the need.

PyPI	`pip install databroker`
Conda	`conda install -c conda-forge databroker`
Source code	https://github.com/bluesky/databroker
Documentation	https://blueskyproject.io/databroker

The bundle of metadata and data looks like this, for example.

>>> run
BlueskyRun
  uid='4a794c63-8223-4893-895e-d16e763188a8'
  exit_status='success'
  2020-03-07 09:17:40.436 -- 2020-03-07 09:28:53.173
  Streams:
    * primary
    * baseline

Additional user metadata beyond what is shown is stored in run.metadata. The bundle contains some number of logical tables of data (“streams”). They can be accessed by name and read into a standard data structure from xarray.

>>> run.primary.read()
<xarray.Dataset>
Dimensions:                   (time: 411)
Coordinates:
  * time                      (time) float64 1.584e+09 1.584e+09 ... 1.584e+09
Data variables:
    I0                        (time) float64 13.07 13.01 12.95 ... 9.862 9.845
    It                        (time) float64 11.52 11.47 11.44 ... 4.971 4.968
    Ir                        (time) float64 10.96 10.92 10.88 ... 4.761 4.763
    dwti_dwell_time           (time) float64 1.0 1.0 1.0 1.0 ... 1.0 1.0 1.0 1.0
    dwti_dwell_time_setpoint  (time) float64 1.0 1.0 1.0 1.0 ... 1.0 1.0 1.0 1.0
    dcm_energy                (time) float64 1.697e+04 1.698e+04 ... 1.791e+04
    dcm_energy_setpoint       (time) float64 1.697e+04 1.698e+04 ... 1.791e+04

Common search queries can be done with a high-level Python interface.

>>> from databroker.queries import TimeRange
>>> catalog.search(TimeRange(since="2020"))

Custom queries can be done with the MongoDB query language.

>>> query = {
...    "motors": {"$in": ["x", "y"]},  # scanning either x or y
...    "temperature" {"$lt": 300},  # temperature less than 300
...    "sample.element": "Ni",
... }
>>> catalog.search(query)

See the tutorials for more.

About the documentation¶

Why is the documentation structured this way?

Reference

Index