mordor2 0.0.55

Python Deployment Tool

Indexes

• Introduction
• Developers' guide
• Configuration
  • Configuration directory
  • Configuration structure
    • Hosts section
    • Deployments section
  • Deal with Application Configurations
• Sample Commands
  • Init target host
  • Stage application to target
  • Run a command on target
• Environment ENV_HOME
• Application Structure
• File Structure on Host

Introduction

Mordor is a tool helps you to deploy your python application.

• 2022-11-05: Support for python 2 has been deprecated.

Developers' guide

This is for developers who want to adding features or fix bugs for mordor. Please see For Developers

Configuration

Configuration directory

Mordor deploys your application using configurations, and configurations are located in a directory.

Mordor locates the configuration directory with the following order:

1. You can specify it with -c option in command line.
2. You can specify it with environment variable MORDOR_CONFIG_DIR
3. Fall back to ~/.mordor

• You can config mordor using either yaml or json format for your configuration file
  • For yaml format, you should provide config.yaml in configuration directory.
  • For json format, you should provide config.json in configuration directory.

Configuration structure

Here is an example config.json:

{
    "hosts": {
        "mordortest": {
            "ssh_host"  : "mordortest",
            "env_home"  : "/root/mordor",
            "python3"   : "/usr/bin/python3"
        }
    },
    "deployments": {
        "sample_beta": {
            "name"        : "sample",
            "stage"       : "beta",
            "home_dir"    : "/home/stonezhong/DATA_DISK/projects/mordor/sample",
            "deploy_to"   : [ "mordortest" ],
            "use_python3" : true,
            "config"      : {
                "foo.json": "copy"
            },
            "requirements": "requirements.txt",
        }
    }
}

or in yaml format config.yaml:

hosts:
    mordortest:
        ssh_host: mordortest
        env_home: /root/mordor
        python3: /usr/bin/python3
deployments:
    sample_beta:
        name: sample
        stage: beta
        home_dir: /home/stonezhong/DATA_DISK/projects/mordor/sample
        deploy_to:
            - mordortest
        use_python3: Yes
        requirements: requirements.txt
        config:
            - foo.json: copy

Hosts section

• In hosts section, you need to list all your hosts which you want to deploy to. The key is the host id, value is the configuration for the host, here are fields for value:
  • python3: Optional, please set python3 interrupter location, if you do not specify, mordor will assume it is /usr/bin/python3
  • env_home: Please set your mordor home directory.
  • ssh_host Optional, set your ssh hostname, if you do not specify, it will be the host id. Normally it should match what you have in your ~/.ssh/config file, You need to make sure you can ssh to each machine without entering password, you can config your ~/.ssh/config if needed

Deployments section

• In deployments section, you need to list all the deployments you have, key is the deployment id, value is the configuration for the deployment, here are the fields for value:
  • name is the name of the application, if missing, then the deployment id becomes the application name
  • stage is the name of the stage, usually it is something like beta, prod, etc, but it can be anything
    • The same application can have as many stages as it supports, but each host can only deploy one stage. For example, you cannot deploy both beta and prod stage of the same app to the same host
  • deploy_to is a list of the host ids
  • use_python3: set to false if your app uses python2, default is True
  • requirements: filename for requirements, which specify the python package dependency, default to requirements.txt
  • the config section list all the config file you need to deploy to host
  • stage: the stage of this deployment, if missing, then stage is ""

Deal with application configs

When mordor looks for a config whose name is config_name to deploy on a host, it looks for it in the following order:

• host specific directory, in {base_config_dir}/configs/{app_name}/{stage}/{host_name}/{config_name}
• stage specific directory, in {base_config_dir}/configs/{app_name}/{stage}/{config_name}
• in config directory, in {base_config_dir}/configs/{app_name}/{config_name}

Mordor supports 3 types of configuration:

• "copy" -- it simply copy the config file to the host
• "convert" -- the config is a python template string, you can refer the following context:

config_dir
env_home
app_name

• "template" -- the config is a jinja template string, you can refer the following context:

host_name
config_dir
log_dir
data_dir
env_home
app_name

Please visit here for a working example.

Sample commands

Init target host

Every host need to be initialized for mordor before you can stage application to it. Here is an example on how to initialize a host:

# initialize mordor on target host mordortest, using config file from /home/stonezhong/testmordor/.mordor
mordor -c /home/stonezhong/testmordor/.mordor -a init-host -o mordortest

Stage application to target

Here is an example to stage an application to a host and setup the python virtual environment for the application:

# stage application sample to beta stage
# the application will be copied to the target machine
# configuration will be copied to the target machine
# python virtual environment will be created on target machine
mordor -c /home/stonezhong/testmordor/.mordor -a stage -p sample -s beta --update-venv

• In most cases, you just need to do --update-venv once, unless you update the requirements.txt, or first time you stage the application.
• Via application manifest, you can let mordor to trigger an command after the application is staged on a host.

Run a command on target

# run command
# application is "sample", stage is "beta", command line is "foo xyz abc"
mordor -c /home/stonezhong/testmordor/.mordor -a run -p sample -s beta -cmd "foo xyz abc"

Application Structure

You can look at the Sample

• You need to have a manifest.json file, you normally want to bump the version if you make changes to your application.
• You need to have a requirements.txt in your application root directory which tells list of packages you need to install
• Optionally, if you want to support running remote command, you need to have a dispatch.py. When you run mordor -a run ..., dispatch.py owns the execution of the command. For details, see dispatch.py as example.

Command line options

mordor \
  <action> \
  -c <mordor_config_base> \
  -o <target_name> \
  -p <app_name> \
  -s <stage> \
  [--update-venv] \
  [--config-only] \
  -cmd="<your command here>"

# action, could be `init-host`, `stage` or `run`
# -c, optional, you can specify the mordir configration directory location
# -o, specify the the target host id.
#     for init-host, you must specify this
#     for stage or run, if missing, then the scope is all the host for the stage
# -p, the application name
# -s, the stage name, if missing, the stage name is empty string
# -cmd, the command you want to run when your action is "run"
# --update-venv, optional, when specified, mordor will update python virtual environment for the app
# --config-only, optional, when specified, mordor only update the application config.

Environment ENV_HOME

After modor is initialized on target, target will have a environment variable ENV_HOME, set to the env_home setting from your host setting of your mordor config file.

File Structure on Host

$ENV_HOME
  |
  +-- apps                                  Home directory for all applications
  |     |
  |     +-- <application name>              Home directory for an application
  |         |
  |         +-- <version 1>                 Directory for version 1 of application
  |         |
  |         +-- <version 2>                 Directory for version 2 of application
  |         |
  |         +-- current                     A symlink to the current version
  |
  +-- bin                                   Some tools used by mordor
  |
  +-- configs                               Home directory for configs for all applications
  |     |
  |     +-- <application name>              Config for an application
  |            |
  |            +-- config1                  depends on your deployment's `config` settings
  |            |
  |            +-- config2
  |
  +-- logs                                  Home directory for logs for all applications
  |     |
  |     +-- <application name>              Logs for an application
  |
  +-- pids                                  Directory for pid for each application
  |     |
  |     +-- <application name>              pid directory for the application
  |             |
  |             +-- main.pid                An application may have many pid files.
  |
  +-- venvs                                 Home for virtual envs for all application
  |     |
  |     +-- <application name>_<version>    Virtual env for a given application with given version
  |     |
  |     +-- <application_name>              A symlink points to the current version
  |
  +-- data
  |     |
  |     +-- <application name>
  |
  +-- temp                                  Temporary directory

Note, stage action does not touch the data directory, it only update code and config. So data is kept the same after your stage action.