About this package
Here are set of internal tools that are shared between different projects internally. Originally most tools related to testing, so they provide some base classes for various cases in testing
NOTE: all our tools are intentially support only 3.8+ python.
Some might work with other versions, but we're going to be free from all these crutches to backport things like async/await
to lower versions, so if it works - fine, if not - feel free to send PR, but it isn't going to be merged all times.
Testing helpers
Caching decorators
from fan_tools.python import cache_async
@cache_async[type(dict)](fname, model, {})
async def func():
return model
from fan_tools.python import memoize
@memoize
def func(*args, **kwargs):
return json.dumps(
{
'args': args,
'kwargs': kwargs,
}
)
ApiUrls
Defined in fan_tools/testing/__init__.py
. Required for defining nested urls with formatting.
You can use it in fixtures, like:
@pytest.fixture(scope='session')
def api(api_v_base):
yield ApiUrls('{}/'.format(api_v_base), {
'password_reset_request': 'password/request/code/',
'password_reset': 'password/reset/',
'user_review_list': 'user/{user_id}/review/',
'user_review': 'user/{user_id}/review/{review_id}/',
'wine_review': 'wine/{wine_id}/review/',
'drink_review': 'drink/{drink_id}/review/',
})
def test_review_list(user, api):
resp = user.get_json(api.user_review_list(user_id=user1.id), {'page_size': 2})
PropsMeta
You can find source in fan_tools/testing/meta.py
.
For now it convert methods that are started with prop__
into descriptors with cache.
class A(metaclass=PropsMeta):
def prop__conn(self):
conn = SomeConnection()
return conn
Became:
class A:
@property
def conn(self):
if not hasattr(self, '__conn'):
setattr(self, '__conn', SomeConnection())
return self.__conn
Thus it allows quite nice style of testing with lazy initialization. Like:
class MyTest(TestCase, metaclass=PropsMeta):
def prop__conn(self):
return psycopg2.connect('')
def prop__cursor(self):
return self.conn.cursor()
def test_simple_query(self):
self.cursor.execute('select 1;')
row = self.cursor.fetchone()
assert row[0] == 1, 'Row: {}'.format(row)
Here you just get and use self.cursor
, but automatically you get connection and cursor and cache they.
This is just simple example, complex tests can use more deep relations in tests. And this approach is way more easier and faster than complex setUp
methods.
fan_tools.unix helpers
Basic unix helpers
- run - run command in shell
- succ - wrapper around
run
with return code and stderr check - wait_socket - wait for socket awailable (eg. you can wait for postgresql with
wait_socket('localhost', 5432)
- asucc - asynchronous version of
succ
for use with await
. supports realtime logging - source - acts similar to bash 'source' or '.' commands.
- cd - contextmanager to do something with temporarily changed directory
interpolate_sysenv
Format string with system variables + defaults.
PG_DEFAULTS = {
'PGDATABASE': 'postgres',
'PGPORT': 5432,
'PGHOST': 'localhost',
'PGUSER': 'postgres',
'PGPASSWORD': '',
}
DSN = interpolate_sysenv('postgresql://{PGUSER}:{PGPASSWORD}@{PGHOST}:{PGPORT}/{PGDATABASE}', PG_DEFAULTS)
fan_tools.fan_logging.JSFormatter
Enable json output with additional fields, suitable for structured logging into ELK or similar solutions.
Accepts env_vars
key with environmental keys that should be included into log.
import logging
import logging.config
LOGGING = {
'version': 1,
'disable_existing_loggers': True,
'formatters': {
'json': {
'()': 'fan_tools.fan_logging.JSFormatter',
'env_vars': ['HOME'],
},
'standard': {
'format': '%(asctime)s [%(levelname)s] %(name)s: %(message)s'
},
},
'handlers': {
'default': {
'level': 'DEBUG',
'class': 'safe_logger.TimedRotatingFileHandlerSafe',
'filename': 'test_json.log',
'when': 'midnight',
'interval': 1,
'backupCount': 30,
'formatter': 'json',
},
},
'loggers': {
'': {
'handlers': ['default'],
'level': 'DEBUG',
},
},
}
logging.config.dictConfig(LOGGING)
log = logging.getLogger('TestLogger')
log.debug('test debug')
log.info('test info')
log.warn('test warn')
log.error('test error')
fan_tools.mon_server.MetricsServer
FastAPI based server that servers metrics in prometheus format.
import uvicorn
from fan_tools.mon_server.certs import update_certs_loop
app = FastAPI()
mserver = MetricsServer(app)
mserver.add_task(update_certs_loop, hosts=['perfectlabel.io', 'robopickles.com'])
uvicorn.run(app, host='0.0.0.0', port=os.environ.get('MONITORING_PORT', 8000))
fan_tools.backup
There are two backup helpers: fan_tools.backup.s3.S3backup
and fan_tools.backup.gcloud.GCloud
We're assuming that backup script has access to backup execution and dump directory.
Default setup includes support for docker container that access DB.
By default script provides interface for monitoring (last backup date).
fan_tools.backup.s3.S3backup
provides external script called fan_s3_backup
that has accepts some configuration via environmental variables.
- ENABLE_BACKUP - you need enable this by setting to non
false
value, default: false - BACKUP_DB_CONTAINER - container for backup command execution
- BACKUP_DB_SCRIPT - command for exectuion on db server from above. default:
/create_backup.py
- BACKUP_COMMAND - overrides all above
-b/--bucket
- to define bucket. default for s3: environmental variable AWS_BACKUP_BUCKET- BACKUP_PREFIX or
-p/--prefix
- directory backup prefix, usually it is subfolder for dumps, default: backups/
-d/--daemonize
- should we run in daemonized mode- MONITORING_PORT - port for listen when run in daemonized mode. default: 80
S3 specific:
- AWS_BACKUP_KEY
- AWS_BACKUP_SECRET
- AWS_BACKUP_BUCKET
fan_tools.drf.serializers.EnumSerializer
Allow you to deserealize incoming strings into Enum
values.
You should add EnumSerializer
into your serializers by hand.
from enum import IntEnum
from django.db import models
from rest_framework import serializers
from fan_tools.drf.serializers import EnumSerializer
class MyEnum(IntEnum):
one = 1
two = 2
class ExampleModel(models.Model):
value = models.IntegerField(choices=[(x.name, x.value) for x in MyEnum])
class ExampleSerializer(serializers.ModelSerializer):
value = EnumSerializer(MyEnum)
Due to Enum
and IntegerField
realizations you may use Enum.value
in querysets
ExampleModel.objects.filter(value=MyEnum.two)
fan_tools.django.log_requests.LoggerMiddleware
LoggerMiddleware will log request meta + raw post data into log.
For django<1.10 please use fan_tools.django.log_requests.DeprecatedLoggerMiddleware
fan_tools.django.request_uniq
Decorator adds a unique for each uwsgi request dict as first function
argument.
For tests mock _get_request_unique_cache
fan_tools.django.call_once_on_commit
Make function called only once on transaction commit. Here is examples
where function do_some_useful
will be called only once after
transaction has been committed.
class SomeModel(models.Model):
name = IntegerField()
@call_once_on_commit
def do_some_useful():
pass
def hook(sender, instance, **kwargs):
do_some_useful()
models.signals.post_save.connect(hook, sender=SomeModel)
with transaction.atomic():
some_model = SomeModel()
some_model.name = 'One'
some_model.save()
some_model.name = 'Two'
some_model.save()
For tests with nested transactions (commit actually most times is not
called) it is useful to override behaviour call_once_on_commit
when decorated function executed right in place where it is called.
To do so mock on_commit
function. Example pytest fixture:
@pytest.fixture(scope='session', autouse=True)
def immediate_on_commit():
def side_effect():
return lambda f: f()
with mock.patch('fan_tools.django.on_commit', side_effect=side_effect) as m:
yield m
fan_tools.django.fields.ChoicesEnum
Used for choices attribute for in model field
class FooBarEnum(ChoicesEnum):
foo = 1
bar = 2
class ExampleModel(models.Model):
type = models.IntegerField(choices=FooBarEnum.get_choices())
fan_tools.django.db.utils.set_word_similarity_threshold
Allow to set postgres trigram word similarity threshold for default django database connection
set_word_similarity_threshold(0.4)
fan_tools.django.contrib.postgres.models.LTreeModel
Django Model containing postgres ltree
class LTreeExampleModel(LTreeModel):
fan_tools.django.contrib.postgres.fields.LTreeDescendants
Lookup for postgres ltree descendants
LTreeExampleModel.objects.filter(path__descendants='root.level1')
fan_tools.django.contrib.postgres.fields.LTreeNlevel
Lookup for postgres ltree by level depth
LTreeExampleModel.objects.filter(path__nlevel=2)
fan_tools.django.db.pgfields.SimilarityLookup
Postgres text %> text
operator
# Add this import to models.py (file should be imported before lookup usage)
import fan_tools.django.db.pgfields # noqa
Books.objects.filter(title__similar='Animal Farm')
fan_tools.django.db.pgfields.WordSimilarity
Postgres text1 <<-> text2
operator. It returns 1 - word_similarity(text1, text2)
from django.db.models import Value, F
similarity = WordSimilarity(Value('Animal Farm'), F('title'))
Books.objects.annotate(similarity=similarity)
fan_tools.drf.filters.NumberInFilter
Django filter that match if integer is in the integers list separated by comma
class ExampleFilterSet(FilterSet):
example_values = NumberInFilter(field_name='example_value', lookup_expr='in')
fan_tools.django.mail.Mail
Send text and html emails using django templates.
Mail(
recipient_list=[user.email],
template_name='user/emails/reset_password',
context={
'frontend_url': settings.FRONTEND_URL,
},
).send()
fan_tools.django.url.build_absolute_uri
Get domain section of absolute url of current page using django request object.
build_absolute_uri(request)
fan_tools.drf.forms.use_form
Helps to use power of serializers for simple APIs checks.
from rest_framework import serializers
from rest_framework.decorators import api_view
from fan_tools.drf import use_form
class SimpleForm(serializers.Serializer):
test_int = serializers.IntegerField()
test_str = serializers.CharField()
@api_view(['GET'])
@use_form(SimpleForm)
def my_api(data):
print(f'Data: {data["test_int"]} and {data["test_str"]}')
Allow turn off pagination by specifying zero page_zize.
REST_FRAMEWORK = {
'DEFAULT_PAGINATION_CLASS': 'fan_tools.drf.pagination.ApiPageNumberPagination',
...
}
fan_tools.rest_framework.renderers.ApiRenderer
Pretty Django Rest Framework API renderer with error codes.
REST_FRAMEWORK = {
'DEFAULT_RENDERER_CLASSES': (
'fan_tools.drf.renderers.ApiRenderer',
},
...
}
fan_tools.rest_framework.handlers.api_exception_handler
Pretty Django Rest Framework API exception handler with error codes.
REST_FRAMEWORK = {
'EXCEPTION_HANDLER': 'fan_tools.drf.handlers.api_exception_handler',
...
}
fan_tools.drf.asserts.assert_validation_error
Helper assert function to be used in tests to match the validation error codes.
assert_validation_error(response, 'email', 'unique')
fan_tools.aio_utils.DbRecordsProcessorWorker
Asyncio worker which wait for new records in postgres db table and process them.
fan_tools.aio_utils.dict_query/sql_update
aiopg shortcuts
fan_tools.python.execfile
Backport of python's 2 execfile
function.
Usage: execfile('path/to/file.py', globals(), locals())
Returns: True if file exists and executed, False if file doesn't exist
fan_tools.doc_utils.fan_sphinx
Sphinx extensions to generate documentation for django restframework serializers and examples for http requests.
In order to use them specify dependency for package installation:
pip install fan_tools[doc_utils]
Usage:
# Add to Sphinx conf.py
extensions = [
# ...
'fan_tools.doc_utils.fan_sphinx.dyn_serializer',
'fan_tools.doc_utils.fan_sphinx.http_log'
]
Commands
fan_env_yaml
Convert template yaml with substituion of %{ENV_NAME}
strings to appropriate environment variables.
Usage: fan_env_yaml src_file dst_file
fan_ci_script
Helper to run default CI pipeline. Defaults are set up for giltab defaults. Includes stages:
- build docker image with temporary name (commit sha by default)
- run tests (optional)
- push branch (by default only for master and staging branches)
- push tag, if there are tags
- cache image with common name
- delete image with temporary name
It's optimized for parallel launches, so you need to use unique temporary name (--temp-name
). We want keep our system clean if possible, so we'll delete this tag in the end. But we don't want to repeat basic steps over and over, so we will cache image with common cache name (--cache-name
), it will remove previous cached image.
fan_wait
Wait for socket awailable/not-awailable with timeout.
# Wait until database port up for 180 seconds
fan_wait -t 180 postgres 5432
# Wait until nginx port down for 30 seconds
fan_wait -t 30 nginx 80
run_filebeat
- checks environmental variables
-e KEY=VALUE -e KEY2=VALUE2
- converts yaml template
fan_env_yaml {TEMPLATE} /tmp/filebeat.yml
- run
/usr/bin/filebeat /tmp/filebeat.yml
run_filebeat -e CHECKME=VALUE path_to_template
doc_serializer
- output rst with list of serializers
- generates documentation artifacts for serializers
usage: doc_serializer [-h] [--rst] [--artifacts]
Parse serializers sources
optional arguments:
-h, --help show this help message and exit
--rst Output rst with serializers
--artifacts Write serializers artifacts
image_utils.Transpose
Save rotated by exif tag images. Some browsers/applications don't respect this tag,
so it is easier to do that explicitly.
class Image(models.Model):
uploaded_by = models.ForeignKey(User, blank=True, null=True, on_delete=models.SET_NULL)
image = models.ImageField(blank=True, upload_to=image_upload_to)
thumb_image = models.ImageField(blank=True, upload_to=thumb_upload_to)
full_url = models.CharField(blank=True, max_length=255)
thumb_url = models.CharField(blank=True, max_length=255)
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
class ImageSerializer(ModelSerializer):
class Meta:
model = Image
fields = ['id', 'created', 'updated', 'full_url', 'thumb_url']
class UploadImageView(views.GenericAPIView):
permission_classes = [IsAuthenticated]
def post(self, request, *args, **kwargs):
image_data = request.data['image']
transformed_image = Transpose().process(image_data)
obj = Image.objects.create(uploaded_by=request.user, image=transformed_image)
obj.full_url = obj.image.url
obj.save()
s = ImageSerializer(instance=obj)
return Response(s.data)
fan_tools.metrics
Helper to send metrics. Example for datadog
Usually you want to setup some kind of notification for metric with name error_metric
. It is sent by send_error_metric
.
For DataDog your metric query will look like:
sum:error_metric{service:prod*} by {error_type,service}.as_count()
development
tox -e py311-django40 -- --keep-db django_tests
tox -e py311-django40 -- --keep-db --docker-skip django_tests