diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/spack/docs/packaging_guide.rst | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/lib/spack/docs/packaging_guide.rst b/lib/spack/docs/packaging_guide.rst index ecc3f58830..cdf4cc7e3b 100644 --- a/lib/spack/docs/packaging_guide.rst +++ b/lib/spack/docs/packaging_guide.rst @@ -443,26 +443,31 @@ Version URLs By default, each version's URL is extrapolated from the ``url`` field in the package. For example, Spack is smart enough to download version ``8.2.1.`` of the ``Foo`` package above from -``http://example.com/foo-8.2.1.tar.gz``. +http://example.com/foo-8.2.1.tar.gz. If the URL is particularly complicated or changes based on the release, you can override the default URL generation algorithm by defining your -own ``url_for_version()`` function. For example, the developers of HDF5 -keep changing the archive layout, so the ``url_for_version()`` function -looks like: +own ``url_for_version()`` function. For example, the download URL for +OpenMPI contains the major.minor version in one spot and the +major.minor.patch version in another: -.. literalinclude:: ../../../var/spack/repos/builtin/packages/hdf5/package.py - :pyobject: Hdf5.url_for_version +https://www.open-mpi.org/software/ompi/v2.1/downloads/openmpi-2.1.1.tar.bz2 -With the use of this ``url_for_version()``, Spack knows to download HDF5 ``1.8.16`` -from ``http://www.hdfgroup.org/ftp/HDF5/releases/hdf5-1.8.16/src/hdf5-1.8.16.tar.gz`` -but download HDF5 ``1.10.0`` from ``http://www.hdfgroup.org/ftp/HDF5/releases/hdf5-1.10/hdf5-1.10.0/src/hdf5-1.10.0.tar.gz``. +In order to handle this, you can define a ``url_for_version()`` function +like so: -You'll notice that HDF5's ``url_for_version()`` function makes use of a special +.. literalinclude:: ../../../var/spack/repos/builtin/packages/openmpi/package.py + :pyobject: Openmpi.url_for_version + +With the use of this ``url_for_version()``, Spack knows to download OpenMPI ``2.1.1`` +from http://www.open-mpi.org/software/ompi/v2.1/downloads/openmpi-2.1.1.tar.bz2 +but download OpenMPI ``1.10.7`` from http://www.open-mpi.org/software/ompi/v1.10/downloads/openmpi-1.10.7.tar.bz2. + +You'll notice that OpenMPI's ``url_for_version()`` function makes use of a special ``Version`` function called ``up_to()``. When you call ``version.up_to(2)`` on a version like ``1.10.0``, it returns ``1.10``. ``version.up_to(1)`` would return ``1``. This can be very useful for packages that place all ``X.Y.*`` versions in -a single directory and then places all ``X.Y.Z`` versions in a subdirectory. +a single directory and then places all ``X.Y.Z`` versions in a sub-directory. There are a few ``Version`` properties you should be aware of. We generally prefer numeric versions to be separated by dots for uniformity, but not all @@ -493,9 +498,6 @@ of its versions, you can add an explicit URL for a particular version: version('8.2.1', '4136d7b4c04df68b686570afa26988ac', url='http://example.com/foo-8.2.1-special-version.tar.gz') -This is common for Python packages that download from PyPi. Since newer -download URLs often contain a unique hash for each version, there is no -way to guess the URL systematically. When you supply a custom URL for a version, Spack uses that URL *verbatim* and does not perform extrapolation. |