magic-app/second.py

"""Less flashy version. More hard-coding."""

from hashlib import md5
from json import dumps, loads
from os import environ, mkdir
from os.path import exists
from pathlib import Path
from shlex import split
from subprocess import run
from typing import Dict

from flask import Flask, render_template, request
from flask_wtf import FlaskForm
from ruamel.yaml import YAML
from wtforms import PasswordField, StringField
from wtforms.validators import URL, DataRequired, Length

app = Flask(__name__)
app.secret_key = b'_5#y2L"F4Q8z\n\xec]/'

yaml = YAML()

APPS_SPEC = {
    "gitea": {
        "url": "https://git.autonomic.zone/compose-stacks/gitea",
        "secrets": [
            "db_passwd",
            "db_root_passwd",
            "internal_token",
            "jwt_secret",
            "secret_key",
        ],
        "configs": ["app_ini"],
    }
}
DATA_DIR = Path("./data")


def clone_app_template(app_name: str) -> None:
    """Git clone an app template repository."""
    clone_path = DATA_DIR / app_name
    clone_url = APPS_SPEC[app_name]["url"]
    run(split(f"git clone {clone_url} {clone_path}"))


def create_docker_secret(key: str, value: str) -> None:
    """Load a docker secret into swarm."""
    command = f"echo {value} | docker secret create {key} -"
    run(command, shell=True)


def dump_db(db: Dict) -> None:
    """Dump the database."""
    with open(DATA_DIR / "db.json", "w") as handle:
        handle.write(dumps(db))


def load_db() -> Dict:
    """Load the database."""
    db_path = DATA_DIR / "db.json"
    if exists(db_path):
        with open(db_path, "r") as handle:
            return loads(handle.read())
    return {}


def get_hash(value: str) -> str:
    """Hash a value for swarm versioning with good 'ol md5."""
    hasher = md5()
    hasher.update(value.encode())
    return hasher.hexdigest()


def arrange_configs_and_secrets(app_name, form_data, env):
    """Version secrets and configs for swarm."""

    def _create_versions(values, secrets=False):
        """Step through listing and create an env var key/val.

        Takes "app_ini" and produces {"APP_INI_VERSION": "app_ini_laksjdklajsdkla"}.
        Hash is based on the value of the input passed in from the form.
        """
        for value in values:
            if value in form_data:
                hashed = get_hash(form_data[value])
                env_key = f"{value.upper()}_VERSION"
                env_val = f"{value}_{hashed}"
                env[env_key] = env_val
                if secrets:
                    create_docker_secret(env_val, form_data[value])

    _create_versions(APPS_SPEC[app_name]["configs"])
    _create_versions(APPS_SPEC[app_name]["secrets"], secrets=True)

    return env


def stack_deploy(app_name, stack_name, env):
    """Depoy an application to the swarm."""
    compose_yml = DATA_DIR / app_name / "compose.yml"
    command = f"docker stack deploy -c {compose_yml} {stack_name}"
    run(split(command), env=env)


def get_loaded_env(app_name, request_form):
    """Load environment from install form for compose.yml injection."""
    environment = environ.copy()
    for key in request_form.keys():
        environment[key.upper()] = request.form[key]
    return environment


class GiteaInstallForm(FlaskForm):
    """Gitea installation form."""

    app_name = StringField("Application name", default="Git with a cup of tea")
    domain = StringField("Domain name", validators=[DataRequired()],)
    stack_name = StringField("Stack name", default="magic-app-gitea")

    db_host = StringField("Database host", default="mariadb:3306")
    db_name = StringField("Database name", default="gitea")
    db_passwd = PasswordField(
        "Database password", validators=[DataRequired(), Length(min=32)],
    )
    db_root_passwd = PasswordField(
        "Database root password", validators=[DataRequired(), Length(min=32)],
    )
    db_type = StringField("Database type", default="mysql")
    db_user = StringField("Database user", default="mysql")
    internal_token = PasswordField(
        "Internal secret token", validators=[DataRequired(), Length(min=105)],
    )
    jwt_secret = PasswordField(
        "JWT secret", validators=[DataRequired(), Length(min=43)],
    )
    secret_key = PasswordField(
        "Secret key", validators=[DataRequired(), Length(min=64)],
    )
    ssh_port = StringField("SSH port", default="2222")


@app.route("/")
def index():
    """Home page for app installation possibilities."""
    return render_template("second/index.html", apps=[app for app in APPS_SPEC])


@app.route("/install/<app_name>")
def install(app_name):
    """Installation page for an app."""
    if app_name == "gitea":
        form = GiteaInstallForm()
    return render_template("second/install.html", app_name=app_name, form=form)


@app.route("/deploy/<app_name>", methods=["POST"])
def deploy(app_name):
    """Deployment end-point for an app."""
    if app_name == "gitea":
        form = GiteaInstallForm(request.form)

    if not form.validate():
        return render_template("second/install.html", app_name=app_name, form=form)

    try:
        mkdir(DATA_DIR)
    except FileExistsError:
        pass

    clone_app_template(app_name)

    env = get_loaded_env(app_name, form.data)
    env = arrange_configs_and_secrets(app_name, form.data, env)

    dump_db({form.data["stack_name"]: form.data})

    stack_deploy(app_name, form.data["stack_name"], env)

    return render_template(
        "second/deploy.html", app_name=app_name, stack_name=form.data["stack_name"]
    )


if __name__ == "__main__":
    app.run(debug=True, host="0.0.0.0")