Pipeline Output Base

Module: astra.models.pipeline

All analysis pipeline output models inherit from PipelineOutputMixin. This mixin provides a standardized set of metadata fields that every pipeline result carries, along with a uniqueness constraint and convenience methods for creating results.

PipelineOutputMixin

Key Fields

Field	Type	Description
task_pk	AutoField	Auto-incrementing primary key for the pipeline task
source_pk	ForeignKeyField	Foreign key linking to the Source
spectrum_pk	ForeignKeyField	Foreign key linking to the Spectrum that was analyzed
v_astra	IntegerField	Astra version (as an integer) that produced the result
created	DateTimeField	Timestamp when the result was created
modified	DateTimeField	Timestamp when the result was last modified
t_elapsed	FloatField	Execution time in seconds
t_overhead	FloatField	Overhead time in seconds
tag	TextField	Optional text tag for organizing results

Uniqueness Constraint

A generated column v_astra_major_minor is computed as v_astra / 1000 (integer division), giving the major.minor version without the patch number. A uniqueness constraint ensures that each spectrum is analyzed at most once per major.minor Astra version:

UNIQUE (spectrum_pk, v_astra_major_minor)

This means if you re-run a pipeline at the same major.minor version, the existing result will be replaced (upserted). Bumping the patch version will not create a new row, but bumping the minor or major version will.

Methods

from_spectrum(spectrum, **kwargs) (classmethod)

A convenience method for creating a pipeline result record from a spectrum object. It automatically extracts spectrum_pk and source_pk from the given spectrum, and validates that any explicitly provided source_pk or spectrum_pk values match those on the spectrum.

from astra.models.apogee import ApogeeCoaddedSpectrumInApStar

spectrum = ApogeeCoaddedSpectrumInApStar.get_by_id(1)
result = MyPipeline.from_spectrum(
    spectrum,
    teff=5000.0,
    logg=2.5,
    fe_h=-0.3,
)
result.save()

Parameters:

• spectrum – A spectrum model instance (e.g., ApogeeCoaddedSpectrumInApStar, BossVisitSpectrum).

• **kwargs – Additional keyword arguments to set on the pipeline result (e.g., derived stellar parameters).

Raises:

• ValueError if an explicitly provided source_pk or spectrum_pk does not match the one on the spectrum.

How Upserts Work

Because of the UNIQUE (spectrum_pk, v_astra_major_minor) constraint, pipeline results can be upserted. When a pipeline runs on a spectrum that already has a result at the same major.minor Astra version, the database will enforce the constraint. Pipeline code can handle this by using Peewee’s on_conflict_replace() or similar mechanisms to update the existing row instead of raising an error.

Extending PipelineOutputMixin

Individual pipeline models (e.g., ASPCAP, The Cannon, Snow White) extend PipelineOutputMixin with their own result fields (stellar parameters, abundances, flags, etc.). See the individual pipeline documentation pages for details on specific pipeline output models.

class MyPipeline(PipelineOutputMixin):
    teff = FloatField(null=True)
    logg = FloatField(null=True)
    fe_h = FloatField(null=True)
    my_flag = BitField(default=0)