Packages¶

class lsst.base.Packages(packages)¶

Bases: object

A table of packages and their versions.

There are a few different types of packages, and their versions are collected in different ways:

Run-time libraries (e.g., cfitsio, fftw): we get their version from interrogating the dynamic library
Python modules (e.g., afw, numpy; galsim is also in this group even though we only use it through the library, because no version information is currently provided through the library): we get their version from the __version__ module variable. Note that this means that we’re only aware of modules that have already been imported.
Other packages provide no run-time accessible version information (e.g., astrometry_net): we get their version from interrogating the environment. Currently, that means EUPS; if EUPS is replaced or dropped then we’ll need to consider an alternative means of getting this version information.
Local versions of packages (a non-installed EUPS package, selected with setup -r /path/to/package): we identify these through the environment (EUPS again) and use as a version the path supplemented with the git SHA and, if the git repo isn’t clean, an MD5 of the diff.

These package versions are collected and stored in a Packages object, which provides useful comparison and persistence features.

Example usage:

from lsst.base import Packages
pkgs = Packages.fromSystem()
print("Current packages:", pkgs)
old = Packages.read("/path/to/packages.pickle")
print("Old packages:", old)
print("Missing packages compared to before:", pkgs.missing(old))
print("Extra packages compared to before:", pkgs.extra(old))
print("Different packages: ", pkgs.difference(old))
old.update(pkgs)  # Include any new packages in the old
old.write("/path/to/packages.pickle")

Parameters:	packages : `dict` A mapping {package: version} where both keys and values are type `str`.

Notes

This is essentially a wrapper around a dict with some conveniences.

Attributes Summary

formats

Methods Summary

`difference`(other)	Get packages in symmetric difference of self and another `Packages` object.
`extra`(other)	Get packages in self but not in another `Packages` object.
`fromBytes`(data, format)	Construct the object from a byte representation.
`fromSystem`()	Construct a `Packages` by examining the system.
`missing`(other)	Get packages in another `Packages` object but missing from self.
`read`(filename)	Read packages from filename.
`toBytes`(format)	Convert the object to a serialized bytes form using the specified format.
`update`(other)	Update packages with contents of another set of packages.
`write`(filename)	Write to file.

Attributes Documentation

formats = {'.pickle': 'pickle', '.pkl': 'pickle', '.yaml': 'yaml'}¶

Methods Documentation

difference(other)¶

Get packages in symmetric difference of self and another Packages object.

Parameters:	other : `Packages` Other packages to compare against.
Returns:	difference : `dict` Packages in symmetric difference. Keys (type `str`) are package names; values (type `str`) are their versions.

extra(other)¶

Get packages in self but not in another Packages object.

Parameters:	other : `Packages` Other packages to compare against.
Returns:	extra : `dict` Extra packages. Keys (type `str`) are package names; values (type `str`) are their versions.

classmethod fromBytes(data, format)¶

Construct the object from a byte representation.

Parameters:	data : `bytes` The serialized form of this object in bytes. format : `str` The format of those bytes. Can be `yaml` or `pickle`.

classmethod fromSystem()¶

Construct a Packages by examining the system.

Determine packages by examining python’s sys.modules, runtime libraries and EUPS.

Returns:	packages : `Packages`

missing(other)¶

Get packages in another Packages object but missing from self.

Parameters:	other : `Packages` Other packages to compare against.
Returns:	missing : `dict` Missing packages. Keys (type `str`) are package names; values (type `str`) are their versions.

classmethod read(filename)¶

Read packages from filename.

Parameters:	filename : `str` Filename from which to read. The format is determined from the file extension. Currently support `.pickle`, `.pkl` and `.yaml`.
Returns:	packages : `Packages`

toBytes(format)¶

Convert the object to a serialized bytes form using the specified format.

Parameters:	format : `str` Format to use when serializing. Can be `yaml` or `pickle`.
Returns:	data : `bytes` Byte string representing the serialized object.

update(other)¶

Update packages with contents of another set of packages.

Parameters:	other : `Packages` Other packages to merge with self.

Notes

No check is made to see if we’re clobbering anything.

write(filename)¶

Write to file.

Parameters:	filename : `str` Filename to which to write. The format of the data file is determined from the file extension. Currently supports `.pickle` and `.yaml`

Navigation

Packages¶