command to update currency file.

Dockerfile

@@ -62,6 +62,9 @@ RUN pip --disable-pip-version-check install -v -e .
 ARG CI_COMMIT_SHA
 ENV CI_COMMIT_SHA=${CI_COMMIT_SHA}
 
+## Download the currency exchange rates from European Central Bank
+RUN flask update-currency-rates
+
 ## Save build date and time
 RUN echo "BUILD_DATE=$(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> /app/.env
 

requirements.txt

@@ -9,6 +9,8 @@ flask-babel
 
 flask-mongoengine==1.0
 
+CurrencyConverter
+
 # Git hooks
 pre-commit
 

src/tjts5901/app.py

@@ -76,6 +76,9 @@ def create_app(config: Optional[Dict] = None) -> Flask:
     from .auth import init_auth
     init_auth(flask_app)
 
+    from .currency import init_currency
+    init_currency(flask_app)
+
     from . import items
     flask_app.register_blueprint(items.bp)
     flask_app.add_url_rule('/', endpoint='index')

src/tjts5901/currency.py

+"""
+Currency module.
+
+This module contains the currency module, which is used to convert currencies.
+
+Uses the ECB (European Central Bank) as the source of currency conversion rates.
+
+To update the currency conversion rates, run the following command:
+    $ flask update-currency-rates
+
+"""
+
+from zipfile import ZipFile
+import urllib.request
+import click
+from currency_converter import (
+    SINGLE_DAY_ECB_URL,
+)
+
+from flask import (
+    Flask,
+    current_app,
+)
+
+
+def init_currency(app: Flask):
+    """
+    Initialize the currency module.
+
+    This function initializes the currency module, and registers the currency
+    converter as an extension.
+
+    :param app: The Flask application.
+    :return: None
+    """
+
+    # Set default currency file path
+    app.config.setdefault('CURRENCY_FILE', app.instance_path + '/currency.csv')
+
+    app.cli.add_command(update_currency_rates)
+
+
+@click.command()
+def update_currency_rates():
+    """
+    Update currency file from the European Central Bank.
+
+    This command is meant to be run from the command line, and is not meant to be
+    used in the application:
+        $ flask update-currency-rates
+
+    :return: None
+    """
+    click.echo('Updating currency file from the European Central Bank...')
+
+    fd, _ = urllib.request.urlretrieve(SINGLE_DAY_ECB_URL)
+    with ZipFile(fd) as zf:
+        file_name = zf.namelist().pop()
+        with open(current_app.config['CURRENCY_FILE'], 'wb') as f:
+            f.write(zf.read(file_name))
+
+    click.echo('Done.')