Is it possible to install a version of a package from github using Haskell stack?
e.g. in a .cabal
or a stack.yaml
file, how can I point a depe
In my case i wanted to depend on a fork of pandoc, specifying a precise commit. It worked by adding the following to stack.yml
:
extra-deps:
- archive: https://github.com/italia/pandoc/archive/1327c564cccf5dfa387a2956443990d9854c85cd.zip
This would work with any branch-like URL on Git. I found my url by browsing the files at the commit and copying the URL from the "Download ZIP" button.
Note that my branch has a specific version, higher than any version Stack could fetch from the resolver. I pinpoint the version in the Cabal dependencies. If the version on that branch would overlap with one available in the resolver's index, i'm not sure about which one would be picked
New syntax for Stack >1.7.1
As @Flip commented, the docs at docs.haskellstack.org
clarify the new syntax for your stack.yaml
is: (note the full commit hash needs to be used)
extra-deps:
- github: apolishch/prime_table
commit: a510622a824af999a809191e8c959b8ea5fa8bdb
- github: apolishch/reactive-banana
commit: 74bac0f86ed172f95bb6f6a31041992fc161cf79
subdirs: reactive-banana
To be clear: dependencies in your stack.yaml
make sure that the packages (which are not in Stackage) are available would some .cabal
file in your project want them, just in case.
You still have to specify the name of the package in build-depends
in your .cabal
file to say you actually depend on the package.
Note it doesn't matter what branch the commit is on, and repos can be forks. When a package is in a subdirectory, you can specify it, otherwise it will default to top-level.
Syntax for Stack >1.6.0
extra-deps:
- github: git@github.com:apolishch/prime_table.git
commit: a510622a824af999a809191e8c959b8ea5fa8bdb
[Edit] I have found that sometimes the syntax from 1.7.1 fails with error message
C:\Users\username\AppData\Local\Programs\stack\x86_64-windows\ghc-8.4.3\lib/../mingw/bin\ar.exe: .stack-work\dist\7d103d30\build\objs-10648\libHSpackagename-0.1.0.0-DlGXqyeqb9MDn2z8KhgjVb.a: No such file or directory
and I solved that by using the 1.6.0 syntax, even though I was using Stack 1.7.1. When using Travis, that will fail because Travis can't clone via SSH without your SSH keys of course. But you can still use the https link as
extra-deps:
- github: https://github.com/apolishch/prime_table.git
commit: a510622a824af999a809191e8c959b8ea5fa8bdb
For stack <1.11:
The documentation for the stack.yaml packages section gives examples of referring to more complex package locations.
packages: - location: . - location: dir1/dir2 - location: https://example.com/foo/bar/baz-0.0.2.tar.gz - location: http://github.com/yesodweb/wai/archive/2f8a8e1b771829f4a8a77c0111352ce45a14c30f.zip - location: git: git@github.com:commercialhaskell/stack.git commit: 6a86ee32e5b869a877151f74064572225e1a0398 - location: hg: https://example.com/hg/repo commit: da39a3ee5e6b4b0d3255bfef95601890afd80709
Then add extra-dep: true
to the package
entry just to tell stack
not to treat the code it pulls in as something you're developing on (e.g., don't load it in GHCi).