Hapistrano is a deployment library for Haskell applications similar to Ruby's Capistrano.
We created Hapistrano because:
- Deploys should be simple, but as close to atomic as possible (eg, they shouldn't require much application downtime).
- Rollback should be trivial to achieve to bring the application back to the last-deployed state.
- Deploys shouldn't fail because of dependency problems.
How it Works
Hapistrano (like Capistrano for Ruby) deploys applications to a new directory marked with a timestamp on the remote host. It creates this new directory quickly by placing a git repository for caching purposes on the remote server.
When the build process completes, it switches a symlink to the
release directory, and optionally restarts the web server.
By default, Hapistrano keeps the last five releases on the target host filesystem and deletes previous releases to avoid filling up the disk.
Hapistrano 0.3.0.0 looks for a configuration file called
typically looks like this:
deploy_path: '/var/projects/my-project' host: myserver.com port: 2222 repo: 'https://github.com/stackbuilders/hapistrano.git' revision: origin/master build_script: - stack setup - stack build restart_command: systemd restart my-app-service
The following parameters are required:
deploy_path— the root of the deploy target on the remote host.
repo— the origin repository.
revision— the SHA1 or branch to deploy. If a branch, you will need to specify it as
origin/branch_namedue to the way that the cache repo is configured.
The following parameters are optional:
host— the target host, if missing,
localhostwill be assumed (which is useful for testing and playing with
port— SSH port number to use. If missing, 22 will be used.
build_script— instructions how to build the application in the form of shell commands.
restart_command— if you need to restart a remote web server after a successful rollback, specify the command that you use in this variable. It will be run after both deploy and rollback.
After creating a configuration file as above, deploying is as simple as:
$ hap deploy
Rollback is also trivial:
$ hap rollback # to rollback to previous successful deploy $ hap rollback -n 2 # go two deploys back in time, etc.
What to do when compiling on server is not viable
Sometimes the target machine (server) is not capable of compiling your
application because e.g. it has not enough memory and GHC exhausts it all.
You can copy pre-compiled files from local machine or CI server using
copy_files: - src: '/home/stackbuilders/my-file.txt' dest: 'my-file.txt' copy_dirs: - src: .stack-work dest: .stack-work
src maybe absolute or relative, it's path to file or directory on local
dest may only be relative (it's expanded relatively to cloned
repo) and specifies where to put the files/directories on target machine.
Directories and files with clashing names will be overwritten. Directories
are copied recursively.
MIT, see the LICENSE file.
Pull requests for modifications to this program are welcome. Fork and open a PR. Feel free to email me if you have questions about what may be accepted before working on a PR.
If you're looking for a place to start, you may want to check the open issue.
- Reduced verbosity of some commands to make reading logs easier.
- Restart command is now invoked after activation of new release (is it should).
- Fix a typo in flag that specifies SSH port for
- Ensure that containing directories for files and directories to copy
exist before invoking
- Add proper set of dependency version constraints.
optparse-applicativeto parse arguments.
- Add support for comments and empty lines to scripts.
- Parse ssh port from
- Drop support for GHCs older than 7.10 (because Chris Done's
pathdoes not compile with them, see: https://github.com/chrisdone/path/issues/46).
- Now Hapistrano uses
hap.yamlfile for all its configuration.
- Added the ability to copy arbitrary files and directories verbatim from local machine to target host.
- Add change log (#23).
README.mdto extra source files.
- Handle missing environment variables more graciously.
- Allow GHC 8 and base 4.9.
Fix tests (#31).
- Use Stack (#17).
- Clean up package (#20).
- Fix tests (#25).
GHC 7.10 support.
Refactoring and documentation improvements.
Various refactoring and relaxed dependency constraints.
Print error messages to
stderr, return non-zero exit code on failure.
- Initial release.