[![Build](https://github.com/stackbuilders/hapistrano/actions/workflows/build.yml/badge.svg?branch=master)](https://github.com/stackbuilders/hapistrano/actions/workflows/build.yml) [![Draft](https://github.com/stackbuilders/hapistrano/actions/workflows/draft.yml/badge.svg)](https://github.com/stackbuilders/hapistrano/actions/workflows/draft.yml) [![Release](https://github.com/stackbuilders/hapistrano/actions/workflows/release.yml/badge.svg)](https://github.com/stackbuilders/hapistrano/actions/workflows/release.yml) # Hapistrano * [Description](#description) * [Purpose](#purpose) * [How it Works](#how-it-works) * [Usage](#usage) * [Environment Variables](#environment-variables) * [What to do when compiling on server is not viable](#what-to-do-when-compiling-on-server-is-not-viable) * [Deploying to multiple machines concurrently](#deploying-to-multiple-machines-concurrently) * [Docker](#docker) * [Nix](#nix) * [Notes](#notes) * [License](#license) * [Contributing](#contributing) # Description Hapistrano is a deployment library for Haskell applications similar to Ruby's [Capistrano](http://capistranorb.com/). ## Purpose 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 `current` 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. ## Usage Hapistrano 0.4.0.0 looks for a configuration file called `hap.yaml` that typically looks like this: ```yaml deploy_path: '/var/projects/my-project' host: user@myserver.com port: 2222 # To perform version control operations repo: 'https://github.com/stackbuilders/hapistrano.git' revision: origin/master # To copy the contents of the directory local_directory: '/tmp/my-project' 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. * Related to the `source` of the repository, you have the following options: - _Git repository_ **default** — consists of two parameters. When these are set, hapistrano will perform version control related operations. **Note:** Only GitHub is supported. * `repo` — the origin repository. * `revision` — the SHA1 or branch to deploy. If a branch, you will need to specify it as `origin/branch_name` due to the way that the cache repo is configured. * `local_directory` — when this parameter is set, hapistrano will copy the contents of the directory. The following parameters are *optional*: * `host` — the target host, if missing, `localhost` will be assumed (which is useful for testing and playing with `hap` locally). You can specify the user that is going to connect to the server here. Example: `user@server.com`. * `port` — SSH port number to use. If missing, 22 will be used. * `shell` — Shell to use. Currently supported: `zsh` ans `bash`. If missing, `Bash` will be used. * `ssh_args` — Optional ssh arguments. Only `-p` is passed via the `port` variable. * `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. * `vc_action` - Controls if version control related activity should take place. It defaults to true. When you don't want activity like cloning, fetching etc. to take place, set this to `false`. * `linux` - Specify, whether or not, the target system where Hapistrano will deploy to is a GNU/Linux or other UNIX (g.e. BSD, Mac). This is set to `true` by default so unless the target system is not GNU/Linux, this should not be necessary. The platform where Hapistrano is running won't affect the available options for commands (g.e. A Mac deploying to an Ubuntu machine, doesn't need this flag) * `release_format` - The release timestamp format, the '--release-format' argument passed via the CLI takes precedence over this value. If neither CLI nor configuration file value is specified, it defaults to 'short' * `keep_releases` - The number of releases to keep, the '--keep-releases' argument passed via the CLI takes precedence over this value. If neither CLI nor configuration file value is specified, it defaults to '5' * `keep_one_failed` - A boolean specifying whether to keep all failed releases or just one (the latest failed release), the '--keep-one-failed' flag passed via the CLI takes precedence over this value. If neither CLI nor configuration file value is specified, it defaults to false (i.e. keep all failed releases). * `linked_files:`- Listed files that will be symlinked from the `{deploy_path}/shared` folder into each release directory during deployment. Can be used for configuration files that need to be persisted (e.g. dotenv files). **NOTE:** The directory structure _must_ be similar in your release directories in case you need to link a file inside a nested directory (e.g. `shared/foo/file.txt`). * `linked_dirs:`- Listed directories that will be symlinked from the `{deploy_path}/shared` folder into each release directory during deployment. Can be used for data directories that need to be persisted (e.g. upload directories). **NOTE:** Do not add a slash `/` at the end of the directory (e.g. `foo/`) because we use `parseRelFile` to create the symlink. * `run_locally:`- Instructions to run locally on your machine in the form of shell commands. Example: ``` run_locally: - pwd - bash deploy.sh ``` Note how we are even able to execute a bash script named `deploy.sh` above. Be sure to use `set -e` in your bash script to avoid headaches. Hapistrano will stop the execution on non-zero exit codes. Without the usage of `set -e`, there is a possibility that your bash script may return a zero exit code even if your intermediate command resulted in an error. After creating a configuration file as above, deploying is as simple as: ```bash $ hap deploy ``` Rollback is also trivial: ```bash $ hap rollback # to rollback to previous successful deploy $ hap rollback -n 2 # go two deploys back in time, etc. ``` * `maintenance_directory:`- The name of the directory on which the maintenance file will be placed. `{deploy_path}/{maintenance_directory}`. The default directory name is `maintenance` * `maintenance_filename:`- The name of the file that is going to be created in the maintenance_directory. It has to have the `.html` extension to be seen in the browser. `{deploy_path}/{maintenance_directory}/{maintenance_filename}`. The default filename is `maintenance.html` ### Environment Variables Configuration files are parsed using [loadYamlSettings](http://hackage.haskell.org/package/yaml-0.10.2.0/docs/Data-Yaml-Config.html#v:loadYamlSettings), therefore, variable substitution is supported. Considering the following configuration file: ```yaml revision: "_env:HAPISTRANO_REVISION:origin/master ... ``` The `revision` value could be overwritten as follows: ```sh HAPISTRANO_REVISION=origin/feature_branch hap deploy ``` ## 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` and `copy_dirs` parameters: ```haskell 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 machine, `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. ## Deploying to multiple machines concurrently Beginning with Hapistrano 0.3.1.0 it's possible to deploy to several machines concurrently. The only things you need to do is to adjust your configuration file and use `targets` parameter instead of `host` and `port`, like this: ```haskell targets: - host: myserver-a.com port: 2222 - host: myserver-b.com # the rest is the same… ``` A few things to note here: * `host` item is required for every target, but `port` may be omitted and then it defaults to `22`. * The deployment will run concurrently and finish when interactions with all targets have finished either successfully or not. If at least one interaction was unsuccessful, the `hap` tool will exit with non-zero exit code. * The log is printed in such a way that messages from several machines get intermixed, but it's guaranteed that they won't overlap (printing itself is sequential) and the headers will tell you exactly which machine was executing which command. If you don't specify `host` and `targets`, `hap` will assume `localhost` as usually, which is mainly useful for testing. ## Docker Docker images hosted on [Docker Hub](https://hub.docker.com/r/stackbuilders/hapistrano) are **no longer up to date**, newer versions are published to [GitHub's Docker Registry](https://github.com/stackbuilders/hapistrano/pkgs/container/hapistrano). ## GH Actions Check the documentation [here](.github/workflows/README.md) ## Nix If you want to use Nix for building Hapistrano, the required release.nix and default.nix are available. For installing the hap binary in your local path: ```bash nix-env -i hapistrano -f release.nix ``` For developing Hapistrano with Nix, you can create a development environment using: ```bash nix-shell --attr env release.nix ``` For just building Hapistrano, you just: ```bash nix-build release.nix ``` ## Enable/disable maintenance mode Present a maintenance page to visitors. Disables your application's web interface by writing a {maintenance_filename} file to each web server. The servers must be configured to detect the presence of this file, and if it is present, always display it instead of performing the request. The maintenance page will just say the site is down for maintenance, and will be back shortly. To enable maintenance mode run: ```bash hapistrano maintenance enable ``` Disabling maintenance mode will remove the file from the {maintenance_directory} it can be done with the following command: ```bash hapistrano maintenance disable ``` ## Notes * Hapistrano is not supported on Windows. Please check: [Issue #96](https://github.com/stackbuilders/hapistrano/issues/96). ## License MIT, see [the LICENSE file](LICENSE). ## Contributing Do you want to contribute to this project? Please take a look at our [contributing guideline](/docs/CONTRIBUTING.md) to know how you can help us build it. --- Stack Builders [Check out our libraries](https://github.com/stackbuilders/) | [Join our team](https://www.stackbuilders.com/join-us/)