lsst.daf.butler¶

This module provides an abstracted data access interface, known as the Butler. It can be used to read and write data without having to know the details of file formats or locations.

Contributing¶

lsst.daf.butler is developed at https://github.com/lsst/daf_butler. You can find Jira issues for this module under the daf_butler component.

Using the Butler¶

Command Line Scripts¶

makeButlerRepo.py¶

Create an empty Gen3 Butler repository.

usage: makeButlerRepo.py [-h] [-c CONFIG] [--standalone] [--outfile OUTFILE]
                         [--verbose] [--override]
                         root

positional arguments¶

root¶: Filesystem path for the new repository. Will be created if it does not exist.

optional arguments¶

-h, --help¶: show this help message and exit

-c <config>, --config <config>¶: Path to an existing YAML config file to apply (on top of defaults).

--standalone¶: Include all defaults in the config file in the repo, insulating the repo from changes in package defaults.

--outfile <outfile>, -f <outfile>¶: Name of output file to receive repository configuration. Default is to write butler.yaml into the specified root.

--verbose, -v¶: Turn on debug reporting.

--override, -o¶: Allow values in the supplied config to override any root settings.

dumpButlerConfig.py¶

Dump either a subset or full Butler configuration to standard output.

usage: dumpButlerConfig.py [-h] [--subset SUBSET] [--searchpath SEARCHPATH]
                           [--verbose]
                           root

positional arguments¶

root¶: Filesystem path for an existing Butler repository or path to config file.

optional arguments¶

-h, --help¶: show this help message and exit

--subset <subset>, -s <subset>¶: Subset of a configuration to report. This can be any key in the hierarchy such as ‘.datastore.root’ where the leading ‘.’ specified the delimiter for the hierarchy.

--searchpath <searchpath>, -p <searchpath>¶: Additional search paths to use for configuration overrides

--verbose, -v¶: Turn on debug reporting.

validateButlerConfiguration.py¶

Validate the configuration files for a Gen3 Butler repository.

usage: validateButlerConfiguration.py [-h] [--collection COLLECTION] [--quiet]
                                      [--datasettype DATASETTYPE]
                                      [--ignore IGNORE]
                                      root

positional arguments¶

root¶: Filesystem path for an existing Butler repository.

optional arguments¶

-h, --help¶: show this help message and exit

--collection <collection>, -c <collection>¶: Collection to refer to in this repository.

--quiet, -q¶: Do not report individual failures.

--datasettype <datasettype>, -d <datasettype>¶: Specific DatasetType(s) to validate (can be comma-separated)

--ignore <ignore>, -i <ignore>¶: DatasetType(s) to ignore for validation (can be comma-separated)

The Dimensions System¶

Concrete Storage Classes¶

DataFrame

Python API reference¶

lsst.daf.butler Package¶

Functions¶

makeBoxWcsRegion(box, wcs, margin) Construct a spherical ConvexPolygon from a WCS and a bounding box.

Classes¶

`AmbiguousDatasetError`	Exception raised when a `DatasetRef` has no ID and a `Registry` operation requires one.
`Butler`([config, butler, collection, run, …])	Main entry point for the data access system.
`ButlerConfig`([other, searchPaths])	Contains the configuration for a `Butler`
`ButlerURI`(uri[, root, forceAbsolute])	Convenience wrapper around URI parsers.
`ButlerValidationError`	There is a problem with the Butler configuration.
`CompositeAssembler`(storageClass)	Class for providing assembler and disassembler support for composites.
`CompositesConfig`([other, validate, …])
`CompositesMap`(config, *, universe)	Determine whether a specific datasetType or StorageClass should be disassembled.
`Config`([other])	Implements a datatype that is used by `Butler` for configuration parameters.
`ConfigSubset`([other, validate, …])	Config representing a subset of a more general configuration.
`ConflictingDefinitionError`	Exception raised when trying to insert a database record when a conflicting record already exists.
`Constraints`(config, *, universe)	Determine whether a `DatasetRef`, `DatasetType`, or `StorageClass` is allowed to be handled.
`ConstraintsConfig`([other])	Configuration information for `Constraints`
`ConstraintsValidationError`	Exception thrown when a constraints list has mutually exclusive definitions.
`DataCoordinate`	An immutable data ID dictionary that guarantees that its key-value pairs identify all required dimensions in a `DimensionGraph`.
`DatasetComponent`(name, storageClass, component)	Component of a dataset and associated information.
`DatasetRef`	Reference to a Dataset in a `Registry`.
`DatasetType`(name, dimensions, storageClass, *)	A named category of Datasets that defines how they are organized, related, and stored.
`DatasetTypeNotSupportedError`	A `DatasetType` is not handled by this routine.
`Datastore`(config, registry[, butlerRoot])	Datastore interface.
`DatastoreConfig`([other, validate, …])
`DatastoreValidationError`	There is a problem with the Datastore configuration.
`DbAuth`([path, envVar, authList])	Retrieves authentication information for database connections.
`DbAuthError`	A problem has occurred retrieving database authentication information.
`DbAuthPermissionsError`	Credentials file has incorrect permissions.
`DeferredDatasetHandle`(butler, …)	This is a class to support deferred loading of a dataset from a butler.
`Dimension`(name, , uniqueKeys, *kwds)	A named data-organization concept that can be used as a key in a data ID.
`DimensionConfig`([other, validate, …])	Configuration that defines a `DimensionUniverse`.
`DimensionElement`(name, *, …)	A named data-organization concept that defines a label and/or metadata in the dimensions system.
`DimensionGraph`	An immutable, dependency-complete collection of dimensions.
`DimensionPacker`(fixed, dimensions)	An abstract base class for bidirectional mappings between a `DataCoordinate` and a packed integer ID.
`DimensionRecord`(*args)	Base class for the Python representation of database records for a `DimensionElement`.
`DimensionUniverse`	A special `DimensionGraph` that constructs and manages a complete set of compatible dimensions.
`ExpandedDataCoordinate`	A data ID that has been expanded to include all relevant metadata.
`FieldSpec`(name, dtype, length, nbytes, …)	A struct-like class used to define a column in a logical Registry table.
`FileDataset`(path, ref, *, formatter, str, …)	A struct that represents a dataset exported to a file.
`FileDescriptor`(location, storageClass[, …])	Describes a particular file.
`FileTemplate`(template)	Format a path template into a fully expanded path.
`FileTemplateValidationError`	Exception thrown when a file template is not consistent with the associated `DatasetType`.
`FileTemplates`(config[, default])	Collection of `FileTemplate` templates.
`FileTemplatesConfig`([other])	Configuration information for `FileTemplates`
`ForeignKeySpec`(table, source, …], target, …)	A struct-like class used to define a foreign key constraint in a logical Registry table.
`Formatter`(fileDescriptor)	Interface for reading and writing Datasets with a particular `StorageClass`.
`FormatterFactory`()	Factory for `Formatter` instances.
`Location`(datastoreRootUri, path)	Identifies a location within the `Datastore`.
`LocationFactory`(datastoreRoot)	Factory for `Location` instances.
`LookupKey`([name, dimensions, dataId, universe])	Representation of key that can be used to lookup information based on dataset type name, storage class name, dimensions.
`MappingFactory`(refType)	Register the mapping of some key to a python type and retrieve instances.
`OrphanedRecordError`	Exception raised when trying to remove or modify a database record that is still being used in some other table.
`Quantum`(*[, taskName, taskClass, dataId, …])	A discrete unit of work that may depend on one or more datasets and produces one or more datasets.
`Registry`(registryConfig[, schemaConfig, …])	Registry interface.
`RepoExport`(registry, datastore, backend, *, …)	Public interface for exporting a subset of a data repository.
`RepoExportBackend`	An abstract interface for data repository export implementations.
`RepoImportBackend`	An abstract interface for data repository import implementations.
`RepoTransferFormatConfig`([other, validate, …])	The section of butler configuration that associates repo import/export backends with file formats.
`Schema`([spec])	The SQL schema for a Butler Registry.
`SchemaConfig`([other, validate, …])
`SkyPixDimension`(name, pixelization)	A special `Dimension` subclass for hierarchical pixelizations of the sky.
`StorageClass`([name, pytype, components, …])	Class describing how a label maps to a particular Python type.
`StorageClassConfig`([other, validate, …])
`StorageClassFactory`([config])	Factory for `StorageClass` instances.
`StoredDatastoreItemInfo`	Internal information associated with a stored dataset in a `Datastore`.
`StoredFileInfo`(formatter, path, …)	Datastore-private metadata associated with a file stored in a Datastore.
`TableSpec`(fields, unique, …]], …)	A struct-like class used to define a logical Registry table (which may also be implemented in the database as a view).
`ValidationError`	Some sort of validation error has occurred.
`YamlRepoExportBackend`(stream)	A repository export implementation that saves to a YAML file.
`YamlRepoImportBackend`(stream)	A repository import implementation that reads from a YAML file.

Class Inheritance Diagram¶

Example datastores¶

lsst.daf.butler.datastores.posixDatastore Module¶

Classes¶

PosixDatastore(config, registry[, butlerRoot]) Basic POSIX filesystem backed Datastore.

Class Inheritance Diagram¶

lsst.daf.butler.datastores.inMemoryDatastore Module¶

Classes¶

`StoredMemoryItemInfo`(timestamp, …)	Internal InMemoryDatastore Metadata associated with a stored DatasetRef.
`InMemoryDatastore`(config[, registry, butlerRoot])	Basic Datastore for writing to an in memory cache.

Class Inheritance Diagram¶

lsst.daf.butler.datastores.chainedDatastore Module¶

Classes¶

ChainedDatastore(config[, registry, butlerRoot]) Chained Datastores to allow read and writes from multiple datastores.

Class Inheritance Diagram¶

Example registries¶

lsst.daf.butler.registries.sqlRegistry Module¶

Classes¶

`SqlRegistryConfig`([other, validate, …])
`SqlRegistry`(registryConfig, schemaConfig, …)	Registry backed by a SQL database.

Class Inheritance Diagram¶

Example formatters¶

lsst.daf.butler.formatters.fileFormatter Module¶

Classes¶

FileFormatter(fileDescriptor) Interface for reading and writing files on a POSIX file system.

Class Inheritance Diagram¶

lsst.daf.butler.formatters.jsonFormatter Module¶

Classes¶

JsonFormatter(fileDescriptor) Interface for reading and writing Python objects to and from JSON files.

Class Inheritance Diagram¶

lsst.daf.butler.formatters.yamlFormatter Module¶

Classes¶

YamlFormatter(fileDescriptor) Interface for reading and writing Python objects to and from YAML files.

Class Inheritance Diagram¶

lsst.daf.butler.formatters.pickleFormatter Module¶

Classes¶

PickleFormatter(fileDescriptor) Interface for reading and writing Python objects to and from pickle files.

Class Inheritance Diagram¶

Support API¶

lsst.daf.butler.core.safeFileIo Module¶

Functions¶

`safeMakeDir`(directory)	Make a directory in a manner avoiding race conditions
`setFileMode`(filename)	Set a file mode according to the user’s umask
`FileForWriteOnceCompareSame`(name)	Context manager to get a file that can be written only once and all other writes will succeed only if they match the initial write.
`SafeFile`(name)	Context manager to create a file in a manner avoiding race conditions
`SafeFilename`(name)	Context manager for creating a file in a manner avoiding race conditions.
`SafeLockedFileForRead`(name)	Context manager for reading a file that may be locked with an exclusive lock via SafeLockedFileForWrite.

Classes¶

`DoNotWrite`
`FileForWriteOnceCompareSameFailure`
`SafeLockedFileForWrite`(name)	File-like object that is used to create a file if needed, lock it with an exclusive lock, and contain file descriptors to readable and writable versions of the file.

Class Inheritance Diagram¶

lsst.daf.butler.core.utils Module¶

Functions¶

`allSlots`(self)	Return combined `__slots__` for all classes in objects mro.
`getClassOf`(typeOrName)	Given the type name or a type, return the python type.
`getFullTypeName`(cls)	Return full type name of the supplied entity.
`getInstanceOf`(typeOrName, args, *kwargs)	Given the type name or a type, instantiate an object of that type.
`getObjectSize`(obj[, seen])	Recursively finds size of objects.
`immutable`(cls)	A class decorator that simulates a simple form of immutability for the decorated class.
`iterable`(a)	Make input iterable.
`slotValuesAreEqual`(self, other)	Test for equality by the contents of all slots, including those of its parents.
`slotValuesToHash`(self)	Generate a hash from slot values.
`stripIfNotNone`(s)	Strip leading and trailing whitespace if the given object is not None.
`transactional`(func)	Decorator that wraps a method and makes it transactional.

Classes¶

`IndexedTupleDict`	An immutable mapping that combines a tuple of values with a (possibly shared) mapping from key to tuple index.
`NamedKeyDict`(*args)	A dictionary wrapper that require keys to have a `.name` attribute, and permits lookups using either key objects or their names.
`NamedValueSet`(elements)	A custom mutable set class that requires elements to have a `.name` attribute, which can then be used as keys in `dict`-like lookup.
`PrivateConstructorMeta`	A metaclass that disables regular construction syntax.
`Singleton`	Metaclass to convert a class to a Singleton.

Class Inheritance Diagram¶

lsst.daf.butler.core.repoRelocation Module¶

Functions¶

replaceRoot(configRoot, butlerRoot) Update a configuration root with the butler root location.

Variables¶

BUTLER_ROOT_TAG The special string to be used in configuration files to indicate that the butler root location should be used.

Navigation

lsst.daf.butler¶

Contributing¶

Using the Butler¶

Command Line Scripts¶

makeButlerRepo.py¶

positional arguments¶

optional arguments¶

dumpButlerConfig.py¶

positional arguments¶

optional arguments¶

validateButlerConfiguration.py¶

positional arguments¶

optional arguments¶

The Dimensions System¶

Concrete Storage Classes¶

Python API reference¶

lsst.daf.butler Package¶

Functions¶

Classes¶

Class Inheritance Diagram¶

Example datastores¶

lsst.daf.butler.datastores.posixDatastore Module¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.datastores.inMemoryDatastore Module¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.datastores.chainedDatastore Module¶

Classes¶

Class Inheritance Diagram¶

Example registries¶

lsst.daf.butler.registries.sqlRegistry Module¶

Classes¶

Class Inheritance Diagram¶

Example formatters¶

lsst.daf.butler.formatters.fileFormatter Module¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.formatters.jsonFormatter Module¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.formatters.yamlFormatter Module¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.formatters.pickleFormatter Module¶

Classes¶

Class Inheritance Diagram¶

Support API¶

lsst.daf.butler.core.safeFileIo Module¶

Functions¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.core.utils Module¶

Functions¶

Classes¶

Class Inheritance Diagram¶

lsst.daf.butler.core.repoRelocation Module¶

Functions¶

Variables¶