Sometimes, already published conda packages contain metadata errors (which can be repaired without needing to rebuild the packages). Most commonly, package dependencies are incorrect, but the package artifacts themselves are fine. A repodata patch specifies which packages are contain errors and how the package should be modified to fix the error.
The best way to make a new patch is to use the patch YAML specification below. Custom patches
in python can be put into the gen_patch_json.py
file.
The files in this directory are used to construct repodata patches for conda-forge. Typically, a single feedstock will have a single YAML file specifying the patches for the packages produced by that feedstock. Use comments liberally to describe why the patch exists.
Patches are specified by two main blocks.
- The
if
block specifies a set of conditions under which the changes in thethen
block are applied. - The different conditions in the
if
block are combined with a logicalAND
. - Any condition may be prefixed by
not_
and will be negated. - The
if
conditions can use shell glob syntax as implemented in the pythonfnmatch
module in the standard library. The optional "?( *)" pattern from extended glob syntax is allowed to match zero or one sequences of spaces plus any other characters. - The
then
section uses the Pythonstring.Template
system to allow theversion
,build_number
,name
, orsubdir
values to be inserted into strings via templates (e.g.,"blah <=${version}"
) at runtime. - Multiple patches can be in the same file using separate YAML documents (i.e., separate the data by
---
on a new line).
if:
# possible conditions
# list of subdirs or a single subdir (e.g., "linux-64")
subdir_in: linux-64
# any subdir but linux-64
not_subdir_in: linux-64
# list of artifact names or a single name (e.g., "ngmix-2.3.0-py38h50d1736_1.conda")
artifact_in: ngmix-2.3.0-py38h50d1736_1.conda
# any key in the repodata entry (e.g., "version" or "build_number") with an operation
<repodata key>_<ge, gt, le, lt>: <value>
# this means version > 1.0.0
version_gt: 1.0.0
# keeps any record with timestamp < value
# you can generate the current time via
# python -c "import time; print(f'{time.time():.0f}000')"
timestamp_lt: 1633470721000
# any key in the repodata entry (e.g., "version" or "build_number") and a list of values or single value
<repodata key>_in: <list or single item>
# this means the build number is in the set {0, 1, 2}
build_number_in: [0, 1, 2]
# has specific dependencies as either a list or a single string
has_depends: numpy* # matches 'numpy', 'nump-blah', or 'numpy 5.6'
has_depends: numpy?( *) # matches 'numpy' or 'numpy 5.6' but not 'numpy-blah'
has_depends: numpy # matches "numpy" exactly (i.e., no pins)
# has specific constraints as either a list or a single key
has_constrains: numpy* # matches 'numpy', 'nump-blah', or 'numpy 5.6'
has_constrains: numpy?( *) # matches 'numpy' or 'numpy 5.6' but not 'numpy-blah'
has_constrains: numpy # matches "numpy" exactly (i.e., no pins)
# single value for a key that should match
<repodata key>: <value>
version: 1.0.0
then:
# list of instructions to change things
# add to the depends or constrains section of the repodata
# this function will not add items already present in the record
- add_<depends or constrains>: <list of str or single str>
# you can use data from the record being patched like this
# only name, version, build_number and subdir are supported
- add_depends: mypackage <=${version}
# remove from the depends or constrains sections of the repodata
- remove_<depends or constrains>: <list of str or single str>
# remove entries from track_features
- remove_track_features: <list of str or str>
# add entries to track_features
- add_track_features: <list of str or str>
# reset the depends or constrains section of the repodata
# this function resets the depends or constrains to the specified value(s)
- reset_<depends or constrains>: <list of str or single str>
# you can use data from the record being patched like this
# only name, version, build_number and subdir are supported
- reset_depends: mypackage <=${version}
# replace entries via an exact match in either the depends or constrains sections
- replace_<depends or constrains>:
# str of thing to be replaced
old: matplotlib ==1.3.0
# thing to replace `old` with
new: matplotlib-base ==1.4.0
# globs are allowed in the "old" field so * needs to be escaped via [*]
- replace_<depends or constrains>:
# str of thing to be replaced
old: matplotlib 1.3.[*] # matches matplotlib 1.3.* exactly
# thing to replace `old` with
new: matplotlib-base ==1.4.0
- replace_<depends or constrains>:
# str of thing to be replaced
old: matplotlib 1.3.* # matches matplotlib 1.3.0, matplotlib 1.3, etc.
# thing to replace `old` with
new: matplotlib-base ==1.4.0
- replace_<depends or constrains>:
# str of thing to be replaced
old: matplotlib ==1.3.0
# thing to replace `old` with
new: ${old},<1.4.0 # you can refer to the "old" value as well
# rename a dependency - this preserves the version information and simply renames the package
- rename_<depends or constrains>:
# str of thing to be renamed
old: matplotlib
# new name for thing
new: matplotlib-base
# relax an exact pin (e.g., blah ==1.0.0) to something like blah >=1.0.0 and possibly with
# `,<2.0a0` added if max_pin='x'
- relax_exact_depends:
# the package name whose constraint should be relaxed
name: matplotlib
# optional string of 'x', 'x.x' etc. format specify an upper bound
# if not given, no upper bound is applied
# max_pin: 'x.x'
# make a dependency version constraint stricter
- tighten_depends:
# package to pin stricter
name: matplotlib # this field can use the fnmatch glob syntax
# you must give one of max_pin or upper_bound
# optional way to specify the new maximum pin as 'x', 'x.x', etc.
max_pin: 'x.x'
# optional way to specify upper bound explicitly
# do not use with `max_pin`
upper_bound: 2.0.1
# make a dependency version constraint looser
- loosen_depends:
# package to pin looser
name: matplotlib # this field can use the fnmatch glob syntax
# you must give one of max_pin or upper_bound
# optional pinning expression 'x', 'x.x', etc. to set how much looser to make the pin
max_pin: 'x.x'
# optional way to specify upper bound explicitly
# do not use with `max_pin`
upper_bound: 2.0.1
---
# more than one patch can be in the file by putting the next one here as a new YAML doc
if:
...
then:
...
---
if:
...
then:
...
Warning
The condition timestamp_lt
is required to prevent your patch from modifying
any packages built in the future. Don't forget to calculate it with python -c "import time; print(f'{time.time():.0f}000')"
and include it in the if:
section of your patch
Tip
You can install a development environment for testing your repodata patch
using the environment file dev-env-for-patches.yaml
The show_diff.py
script in this directory can be used to test out
modifications to gen_patch_json.py
. This scripts shows the difference
between the package records currently available on anaconda.org/conda-forge and those
produced from the patch instructions produced by gen_patch_json.py
.
Usage is:
usage: show_diff.py [-h] [--subdirs [SUBDIRS [SUBDIRS ...]]] [--use-cache]
show repodata changes from the current gen_patch_json
optional arguments:
-h, --help show this help message and exit
--subdirs [SUBDIRS [SUBDIRS ...]]
subdir(s) show, default is all
--use-cache use cached repodata files, rather than downloading
them
Repodata is cached in a cache
directory in the current directory or in the
path specified by the CACHE_DIR
environment variable.
Typically, show_diff.py
is run without any argument to download the
necessary repodata followed by repeated calls to show_diff.py --use-cache
to test out changes to the gen_patch_json.py
script.
Tip
If you're having trouble running show_diff.py
locally, don't despair. You
should still submit your patch. The Azure job also returns this information.
Search the build log for patching repodata:
and copy-paste the output for
all the architectures to your Pull Request. Stop copying once you've reached
patching repodata: 100%
This scheme generates one file per subdir, patch_instructions.json
. This file has entries
instructions = {
"patch_instructions_version": 1,
"packages": defaultdict(dict),
"revoke": [],
"remove": [],
}
remove
are lists of filenames that will not show up in the index but may still be downloadable with a direct URL to the file.
packages
is a dictionary, where keys are package filenames. Values are dictionaries similar to the contents of each package in repodata.json
. Any values provided in packages
here overwrite the values in repodata.json
. Any value set to None is removed.
A tool downloads this package when it sees updates to it, and applies the patch_instructions.json
to the repodata of the conda-forge
channel on anaconda.org
After a patch PR is merged there are no further actions for patch submitters, feedstock maintainers, or conda-forge to take. Anaconda, Inc. manages the infrastructure that applies patches from this repository to the repodata of distributions on anaconda.org/conda-forge/. This infrastructure is related to the process for updating their CDN, so patches should generally be applied and usable within a few hours after a patch PR is merged.