caom2

Common Archive Observation Model - data engineering tools

caom2 module

The caom2 module is a library implementing the Common Archive Observation Model (CAOM-2.3) for manipulating CAOM observations and reading and writing XML documents.

http://www.opencadc.org/caom2/

To create a minimal Simple Observation

import sys
from caom2 import SimpleObservation, TypedOrderedDict, Plane, Artifact,\
                  Part, Chunk, ObservationWriter, ProductType,\
                  ReleaseType, TypedList

observation = SimpleObservation('collection', 'observationID')

observation.planes = TypedOrderedDict(Plane)
plane = Plane('productID')
observation.planes['productID'] = plane

plane.artifacts = TypedOrderedDict(Artifact)
artifact = Artifact('uri:foo/bar', ProductType.SCIENCE, ReleaseType.META)
plane.artifacts['uri:foo/bar'] = artifact

artifact.parts = TypedOrderedDict(Part)
part = Part('name')
artifact.parts['name'] = part

part.chunks = TypedList(Chunk)
chunk = Chunk()
part.chunks.append(chunk)

writer = ObservationWriter()
writer.write(observation, sys.stdout)

The output:

<?xml version='1.0' encoding='UTF-8'?>
<caom2:Observation xmlns:caom2="http://www.opencadc.org/caom2/xml/v2.3" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="caom2:SimpleObservation" caom2:id="00000000-0000-0000-3d6a-420eab45bf2e" caom2:lastModified="2016-11-24T08:40:54.003">
  <caom2:collection>collection</caom2:collection>
  <caom2:observationID>observationID</caom2:observationID>
  <caom2:algorithm>
    <caom2:name>exposure</caom2:name>
  </caom2:algorithm>
  <caom2:planes>
    <caom2:plane caom2:id="00000000-0000-0000-1fe6-420eab45c0bc" caom2:lastModified="2016-11-24T08:40:54.003">
      <caom2:productID>productID</caom2:productID>
      <caom2:artifacts>
        <caom2:artifact caom2:id="00000000-0000-0000-7adf-420eab45c170" caom2:lastModified="2016-11-24T08:40:54.004">
          <caom2:uri>uri:foo/bar</caom2:uri>
          <caom2:productType>science</caom2:productType>
          <caom2:releaseType>meta</caom2:releaseType>
          <caom2:parts>
            <caom2:part caom2:id="00000000-0000-0000-16f0-420eab45c246" caom2:lastModified="2016-11-24T08:40:54.004">
              <caom2:name>name</caom2:name>
              <caom2:chunks>
                <caom2:chunk caom2:id="00000000-0000-0000-0c8f-420eab45c2a1" caom2:lastModified="2016-11-24T08:40:54.004"/>
              </caom2:chunks>
            </caom2:part>
          </caom2:parts>
        </caom2:artifact>
      </caom2:artifacts>
    </caom2:plane>
  </caom2:planes>
</caom2:Observation>

To create a complete Observation

# make it compatible with Python 2 and 3
from __future__ import (absolute_import, division, print_function,
                    unicode_literals)
from datetime import datetime
import sys
from caom2 import SimpleObservation, Plane, Artifact, Part, Chunk,\
                  TypedOrderedDict, ObservationWriter, ProductType, \
                  ReleaseType, TypedList, Target, TargetPosition, \
                  TargetType, ObservationIntentType, Instrument, \
                  Telescope, Environment, DataProductType, Provenance, \
                  CalibrationLevel, Metrics, Proposal, Point, Slice, Axis,\
                  ObservableAxis, CoordAxis1D, CoordAxis2D, SpatialWCS,\
                  SpectralWCS, EnergyTransition, TemporalWCS, CoordFunction1D,\
                  RefCoord, PolarizationWCS

observation = SimpleObservation('collection', 'observationID')
observation.obs_type = 'flat'
observation.intent = ObservationIntentType.SCIENCE
observation.meta_release = datetime(2016, 11, 22, 11, 53, 44, 0)

observation.proposal = Proposal('proposal id')
observation.proposal.pi_name = 'pi name'
observation.proposal.project = 'proposal project'
observation.proposal.title = 'proposal title'
observation.proposal.keywords.update({'proposal', 'key', 'words'})

observation.target = Target('target name')
observation.target.target_type = TargetType.OBJECT
observation.target.standard = False
observation.target.redshift = 1.5
observation.target.keywords.update({'target', 'key', 'words'})

point = Point(1.0, 2.0)
observation.target_position = TargetPosition(point, 'coordsys')
observation.target_position.equinox = 3.0

observation.telescope = Telescope('telescope name')
observation.telescope.geo_location_x = 1.0
observation.telescope.geo_location_y = 2.0
observation.telescope.geo_location_z = 3.0
observation.telescope.keywords.update({'telescope', 'key', 'words'})

observation.instrument = Instrument('instrument name')
observation.instrument.keywords.update({'instrument', 'key', 'words'})

observation.env = Environment()
observation.env.seeing = 0.08
observation.env.humidity = 0.35
observation.env.elevation = 2.7
observation.env.tau = 0.7
observation.env.wavelength_tau = 450e-6
observation.env.ambient_temp = 20.0
observation.env.photometric = True

observation.planes = TypedOrderedDict(Plane)
plane = Plane('productID')
observation.planes['productID'] = plane

plane.meta_release = datetime(2016, 11, 22, 12, 26, 21, 0)
plane.data_release = datetime(2018, 01, 01, 00, 00, 00, 0)
plane.data_product_type = DataProductType.IMAGE
plane.calibration_level = CalibrationLevel.PRODUCT

plane.provenance = provenance = Provenance('name')
plane.provenance.version = 'version'
plane.provenance.product = 'product'
plane.provenance.producer = 'producer'
plane.provenance.run_id = 'run_id'
plane.provenance.reference = 'http://foo/bar'
plane.provenance.last_executed = datetime(2016, 11, 22, 12, 28, 16, 0)
plane.provenance.keywords.update({'provenance', 'key', 'words'})

plane.metrics = Metrics()
plane.metrics.source_number_density = 1.0
plane.metrics.background = 2.0
plane.metrics.background_std_dev = 3.0
plane.metrics.flux_density_limit = 4.0
plane.metrics.mag_limit = 5.0

plane.artifacts = TypedOrderedDict(Artifact)
artifact = Artifact('uri:foo/bar', ProductType.SCIENCE, ReleaseType.META)
plane.artifacts['uri:foo/bar'] = artifact

artifact.content_type = 'application/fits'
artifact.content_length = 12345L

artifact.parts = TypedOrderedDict(Part)
part = Part('name')
artifact.parts['name'] = part
part.product_type = ProductType.SCIENCE

part.chunks = TypedList(Chunk)
chunk = Chunk()
part.chunks.append(chunk)

chunk.product_type = ProductType.SCIENCE
chunk.naxis = 5
chunk.observable_axis = 1
chunk.position_axis_1 = 1
chunk.position_axis_2 = 2
chunk.energy_axis = 3
chunk.time_axis = 4
chunk.polarization_axis = 5

observable_axis = Slice(Axis('observable_ctype', 'observable_cunit'), 1L)
chunk.observable = ObservableAxis(observable_axis)

position_axis = CoordAxis2D(Axis('position_ctype_1', 'position_cunit_1'),
                            Axis('position_ctype_2', 'position_cunit_2'))
chunk.position = SpatialWCS(position_axis)
chunk.position.coordsys = 'position coordsys'
chunk.position.equinox = 2000.0
chunk.position.resolution = 0.5

energy_axis = CoordAxis1D(Axis('energy_ctype', 'energy_cunit'))
chunk.energy = SpectralWCS(energy_axis, 'specsys')
chunk.energy.ssysobs = 'ssysobs'
chunk.energy.ssyssrc = 'ssyssrc'
chunk.energy.restfrq = 1.0
chunk.energy.restwav = 2.0
chunk.energy.velosys = 3.0
chunk.energy.zsource = 4.0
chunk.energy.velang = 5.0
chunk.energy.bandpassName = 'bandpass name'
chunk.energy.resolvingPower = 6.0
chunk.energy.transition = EnergyTransition('H', '21cm')

time_axis = CoordAxis1D(Axis('time_ctype', 'time_cunit'))
chunk.time = TemporalWCS(time_axis)
chunk.time.exposure = 1.0
chunk.time.resolution = 2.0
chunk.time.timesys = 'UTC'
chunk.time.trefpos = 'TOPOCENTER'
chunk.time.mjdref = 3.0

polarization_axis = CoordAxis1D(Axis('STOKES'))
polarization_axis.function = CoordFunction1D(4L, 1.0, RefCoord(1.0, 1.0))
chunk.polarization = PolarizationWCS(polarization_axis)

writer = ObservationWriter()
writer.write(observation, sys.stdout)

The output:

<?xml version='1.0' encoding='UTF-8'?>
<caom2:Observation xmlns:caom2="http://www.opencadc.org/caom2/xml/v2.3" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="caom2:SimpleObservation" caom2:id="00000000-0000-0000-21ae-41feaaab49f6" caom2:lastModified="2016-11-23T13:35:24.404">
  <caom2:collection>collection</caom2:collection>
  <caom2:observationID>observationID</caom2:observationID>
  <caom2:metaRelease>2016-11-22T11:53:44.000</caom2:metaRelease>
  <caom2:algorithm>
        <caom2:name>exposure</caom2:name>
  </caom2:algorithm>
  <caom2:type>flat</caom2:type>
  <caom2:intent>science</caom2:intent>
  <caom2:proposal>
        <caom2:id>proposal id</caom2:id>
        <caom2:pi>pi name</caom2:pi>
        <caom2:project>proposal project</caom2:project>
        <caom2:title>proposal title</caom2:title>
        <caom2:keywords>proposal words key</caom2:keywords>
  </caom2:proposal>
  <caom2:target>
        <caom2:name>target name</caom2:name>
        <caom2:type>object</caom2:type>
        <caom2:standard>false</caom2:standard>
        <caom2:redshift>1.5</caom2:redshift>
        <caom2:keywords>words key target</caom2:keywords>
  </caom2:target>
  <caom2:targetPosition>
        <caom2:coordsys>coordsys</caom2:coordsys>
        <caom2:equinox>3.0</caom2:equinox>
        <caom2:coordinates>
          <caom2:cval1>1.0</caom2:cval1>
          <caom2:cval2>2.0</caom2:cval2>
        </caom2:coordinates>
  </caom2:targetPosition>
  <caom2:telescope>
        <caom2:name>telescope name</caom2:name>
        <caom2:geoLocationX>1.0</caom2:geoLocationX>
        <caom2:geoLocationY>2.0</caom2:geoLocationY>
        <caom2:geoLocationZ>3.0</caom2:geoLocationZ>
        <caom2:keywords>words key telescope</caom2:keywords>
  </caom2:telescope>
  <caom2:instrument>
        <caom2:name>instrument name</caom2:name>
        <caom2:keywords>instrument words key</caom2:keywords>
  </caom2:instrument>
  <caom2:planes>
        <caom2:plane caom2:id="00000000-0000-0000-f768-41feaaab4bbc" caom2:lastModified="2016-11-23T13:35:24.404">
          <caom2:productID>productID</caom2:productID>
          <caom2:metaRelease>2016-11-22T12:26:21.000</caom2:metaRelease>
          <caom2:dataRelease>2018-01-01T00:00:00.000</caom2:dataRelease>
          <caom2:dataProductType>image</caom2:dataProductType>
          <caom2:calibrationLevel>3</caom2:calibrationLevel>
          <caom2:provenance>
                <caom2:name>name</caom2:name>
                <caom2:version>version</caom2:version>
                <caom2:producer>producer</caom2:producer>
                <caom2:runID>run_id</caom2:runID>
                <caom2:reference>http://foo/bar</caom2:reference>
                <caom2:lastExecuted>2016-11-22T12:28:16.000</caom2:lastExecuted>
                <caom2:keywords>provenance words key</caom2:keywords>
          </caom2:provenance>
          <caom2:metrics>
                <caom2:sourceNumberDensity>1.0</caom2:sourceNumberDensity>
                <caom2:background>2.0</caom2:background>
                <caom2:backgroundStddev>3.0</caom2:backgroundStddev>
                <caom2:fluxDensityLimit>4.0</caom2:fluxDensityLimit>
                <caom2:magLimit>5.0</caom2:magLimit>
          </caom2:metrics>
          <caom2:artifacts>
                <caom2:artifact caom2:id="00000000-0000-0000-d905-41feaaab4ca0" caom2:lastModified="2016-11-23T13:35:24.404">
                  <caom2:uri>uri:foo/bar</caom2:uri>
                  <caom2:productType>science</caom2:productType>
                  <caom2:releaseType>meta</caom2:releaseType>
                  <caom2:contentType>application/fits</caom2:contentType>
                  <caom2:contentLength>12345</caom2:contentLength>
                  <caom2:parts>
                        <caom2:part caom2:id="00000000-0000-0000-909d-41feaaab4d2d" caom2:lastModified="2016-11-23T13:35:24.405">
                          <caom2:name>name</caom2:name>
                          <caom2:productType>science</caom2:productType>
                          <caom2:chunks>
                                <caom2:chunk caom2:id="00000000-0000-0000-2ef1-41feaaab4d74" caom2:lastModified="2016-11-23T13:35:24.405">
                                  <caom2:productType>science</caom2:productType>
                                  <caom2:naxis>5</caom2:naxis>
                                  <caom2:observableAxis>1</caom2:observableAxis>
                                  <caom2:positionAxis1>1</caom2:positionAxis1>
                                  <caom2:positionAxis2>2</caom2:positionAxis2>
                                  <caom2:energyAxis>3</caom2:energyAxis>
                                  <caom2:timeAxis>4</caom2:timeAxis>
                                  <caom2:polarizationAxis>5</caom2:polarizationAxis>
                                  <caom2:observable>
                                        <caom2:dependent>
                                          <caom2:axis>
                                                <caom2:ctype>observable_ctype</caom2:ctype>
                                                <caom2:cunit>observable_cunit</caom2:cunit>
                                          </caom2:axis>
                                          <caom2:bin>1</caom2:bin>
                                        </caom2:dependent>
                                  </caom2:observable>
                                  <caom2:position>
                                        <caom2:axis>
                                          <caom2:axis1>
                                                <caom2:ctype>position_ctype_1</caom2:ctype>
                                                <caom2:cunit>position_cunit_1</caom2:cunit>
                                          </caom2:axis1>
                                          <caom2:axis2>
                                                <caom2:ctype>position_ctype_2</caom2:ctype>
                                                <caom2:cunit>position_cunit_2</caom2:cunit>
                                          </caom2:axis2>
                                        </caom2:axis>
                                        <caom2:coordsys>position coordsys</caom2:coordsys>
                                        <caom2:equinox>2000.0</caom2:equinox>
                                        <caom2:resolution>0.5</caom2:resolution>
                                  </caom2:position>
                                  <caom2:energy>
                                        <caom2:axis>
                                          <caom2:axis>
                                                <caom2:ctype>energy_ctype</caom2:ctype>
                                                <caom2:cunit>energy_cunit</caom2:cunit>
                                          </caom2:axis>
                                        </caom2:axis>
                                        <caom2:specsys>specsys</caom2:specsys>
                                        <caom2:ssysobs>ssysobs</caom2:ssysobs>
                                        <caom2:ssyssrc>ssyssrc</caom2:ssyssrc>
                                        <caom2:restfrq>1.0</caom2:restfrq>
                                        <caom2:restwav>2.0</caom2:restwav>
                                        <caom2:velosys>3.0</caom2:velosys>
                                        <caom2:zsource>4.0</caom2:zsource>
                                        <caom2:velang>5.0</caom2:velang>
                                        <caom2:transition>
                                          <caom2:species>H</caom2:species>
                                          <caom2:transition>21cm</caom2:transition>
                                        </caom2:transition>
                                  </caom2:energy>
                                  <caom2:time>
                                        <caom2:axis>
                                          <caom2:axis>
                                                <caom2:ctype>time_ctype</caom2:ctype>
                                                <caom2:cunit>time_cunit</caom2:cunit>
                                          </caom2:axis>
                                        </caom2:axis>
                                        <caom2:timesys>UTC</caom2:timesys>
                                        <caom2:trefpos>TOPOCENTER</caom2:trefpos>
                                        <caom2:mjdref>3.0</caom2:mjdref>
                                        <caom2:exposure>1.0</caom2:exposure>
                                        <caom2:resolution>2.0</caom2:resolution>
                                  </caom2:time>
                                  <caom2:polarization>
                                        <caom2:axis>
                                          <caom2:axis>
                                                <caom2:ctype>STOKES</caom2:ctype>
                                          </caom2:axis>
                                          <caom2:function>
                                                <caom2:naxis>4</caom2:naxis>
                                                <caom2:delta>1.0</caom2:delta>
                                                <caom2:refCoord>
                                                  <caom2:pix>1.0</caom2:pix>
                                                  <caom2:val>1.0</caom2:val>
                                                </caom2:refCoord>
                                          </caom2:function>
                                        </caom2:axis>
                                  </caom2:polarization>
                                </caom2:chunk>
                          </caom2:chunks>
                        </caom2:part>
                  </caom2:parts>
                </caom2:artifact>
          </caom2:artifacts>
        </caom2:plane>
  </caom2:planes>
</caom2:Observation>

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