usage.rst

Usage

To use tg-utils in a project:

import tg_utils

Django Compressor filters

If you're using Django Compressor for compressing CSS/JS, we have a few filters to use clean-css and Uglify JS 2 for compression out of the box.

To use them, add to your Django settings:

COMPRESS_CSS_FILTERS = [
    'compressor.filters.css_default.CssAbsoluteFilter',
    'tg_utils.compressor_filters.CleanCssFilter',
]
COMPRESS_JS_FILTERS = [
    'tg_utils.compressor_filters.UglifyFilter',
]

Note that you need to have clean-css and uglify-js npm packages installed and in $PATH. Django Compressor versions 1.4 to 2.4 (inclusive) are supported.

Health-check endpoint

Make sure the extra dependencies are installed (by specifying [health_check] extra when adding tg_utils to project requirements).

Add health_check app and relevant health-checkers to installed apps:

INSTALLED_APPS = [
    ...
    'health_check',
    'health_check.db',
    'health_check.cache',
    'health_check.storage',
    'health_check.contrib.psutil',
    'health_check.contrib.celery',
    'tg_utils.health_check.checks.elvis',
    'tg_utils.health_check.checks.phantomjs',
    'tg_utils.health_check.checks.celery_beat',
    ...
[

Add healthcheck to your urls.py:

urlpatterns = [
    ...
    url(r'', include('tg_utils.health_check.urls')),
    ...
]

or manually, if you desire different urls:

from tg_utils.health_check.views import HealthCheckViewProtected, HealthCheckViewMinimal

urlpatterns = [
    ...
    url(r'^health/detail/?$', HealthCheckViewProtected.as_view(), name='health-check-detail'),
    url(r'^health/?$', HealthCheckViewMinimal.as_view(), name='health-check'),
    ...
]

Add settings, if required, to settings.py:

# Settings related to views
HEALTH_CHECK_ACCESS_TOKEN = 'secret' # Used to access protected detail view
HEALTH_CHECK_ACCESS_TOKEN_PARAMETER = 'tervisetoken'
HEALTH_CHECK_ACCESS_TOKEN_HEADER = 'HTTP_X_TERVISETOKEN'

# Settings related to checkers
HEALTH_CHECK = {
    # For 'health_check.contrib.psutil'
    'DISK_USAGE_MAX': 90,   # percent
    'MEMORY_MIN': 100,      # in MB

    # For 'tg_utils.health_check.checks.phantomjs'
    'PHANTOMJS_REQUIRES_HEADER_HTML': True,  # Defaults to False, set to true if phantomjs expects header_html data

    # For 'tg_utils.health_check.checks.celery_beat'
    'CELERY_APP': 'my_cool_project.celery.app',  # Celery app instance
    'CELERY_BEAT_CHECK_INTERVAL': 60,            # How frequently to schedule the health check beat, in seconds
    'CELERY_BEAT_DELAY_THRESHOLD': 10,           # Goes to error state if the task does not complete within
                                                 # this number of seconds after it was supposed to be scheduled

}

To access protected detail view, secret token has to be passed as either a GET parameter or HTTP header.