fastapi-serviceutils

Python 3.7 coverage License MIT powered by dephell logo

Services stand for portability and scalability, so the deployment and configuration of these service should be as easy as possible. To achieve this a service based on fastapi-serviceutils is configured using a config.yml. These settings can be overwritten using environment-variables. Dependency management for these services is generalized using a combination of Dephell and Poetry.

For monitoring and chaining of service-calls some default endpoints should always be defined. For example an endpoint to check if the service is alive (/api/alive) and an endpoint to access the config of the service (/api/config). These endpoints are automatically added in services using fastapi-serviceutils if defined in the config.yml of the service.

Because a service should focus on only one task it may be required to create multiple small services in a short time. As always time matters. For this fastapi-serviceutils allows ** fast creation of new services** with create_service.

If an error occurs during a service-call it is important to have detailed logs with a good traceback. To achieve this the default logging of fastapi is optimized in fastapi-serviceutils using loguru.

Fastapi allows easily created swagger-documentation for service-endpoints. This is optimal for clients wanting to integrate these endpoints. For developers of the service an additional apidoc-documentation of the service and the source-code is required (most popular are documentations created using Sphinx or MKDocs). Fastapi-serviceutils based services serve sphinx-based documentations using google-documentation style in the code and rst-files inside the docs-folder.

The development of these services should be as much generalized as possible for easy workflows, as less manual steps as possible for the developer and short onboarding times. For this fastapi-serviceutils includes a Makefile for most common tasks during development. There is also a Tmuxp-config file to create a tmux-session for development.

Features

  • optimized logging using Loguru

  • optimized exception handling by additional exception handler log_exception handler

  • usage of a config.yml-file to configure the service

  • usage of environment-variables (Environment variable overwrites config-value) to configure the service

  • easily serve the apidoc with the service

  • easy deploment using Docker combined with Docker compose

  • fast creation of new service with create_service

  • Makefile and Tmuxp-config for easier development of services based on fastapi-serviceutils using Make and tmux-session

Content

Fastapi-serviceutils contains three subpackages:

  • fastapi_serviceutils.app

  • fastapi_serviceutils.cli

  • fastapi_serviceutils.utils

fastapi_serviceutils.app contains functions and classes for app-configuration (like config.yml file, logger, etc.), handlers and endpoint creation.

fastapi_serviceutils.cli contains executables for easier development like create_service to use the fastapi_serviceutils_template.

fastapi_serviceutils.utils contain utils to interact with external resources like databases and services, testutils and other utilities.

To see detailed usage of these functions and classes, and also recommended service-structure, see exampleservice.

Table of Contents

Usage

exampleservice

The easiest way to explain how to use fastapi-serviceutils is to demonstrate usage inside an exampleservice. Here we will explain the parts of the service and which functions and classes when to use.

Creating new service

To create a new service we use the tool create_service which is available after installing fastapi-serviceutils.

create_service -n exampleservice \
    -p 50001 \
    -a "Dummy User" \
    -e dummy.user@something.info \
    -ep example \
    -o /tmp

This creates the service exampleservice inside the folder /tmp/exampleservice. As author with email we define Dummy User and dummy.user@something.info. The initial endpoint we want to create is example. The service should listen to port 50001.

If we change into the created directory we will have the following folder-structure:

exampleservice
├── app
│   ├── config.yml
│   ├── endpoints
│   │   ├── __init__.py
│   │   └── v1
│   │       ├── errors.py
│   │       ├── example.py
│   │       ├── __init__.py
│   │       └── models.py
│   ├── __init__.py
│   └── main.py
├── .codespell-ignore-words.txt
├── docker-compose.yml
├── Dockerfile
├── docs
│   └── ...
├── .gitignore
├── Makefile
├── .pre-commit-config.yaml
├── pyproject.toml
├── .python-version
├── README.md
├── setup.cfg
├── tests
│   └── __init__.py
└── .tmuxp.yml

The files docker-compose.yml and Dockerfile are required for deployment of the service as docker-container.

.tmuxp.yml is used for development of the service if you prefer to develop inside tmux in combination with for example vim or emacs.

The .python-version defines which python-version this service uses and is used by poetry / dephell workflow inside virtual-environments.

The pyproject.toml is used for dependency-management and package-creation.

setup.cfg contains configurations for tools used during development like yapf, flake8, pytest, etc.

The .pre-commit-config.yaml allows the usage of pre-commit and is also used in the make command make check. It enables running of multiple linters, checkers, etc. to ensure a fixed codestyle.

The Makefile contains helper command like initializing the project, updating the virtual-environment, running tests, etc.

Because codespell is used inside the configuration of pre-commit, the file .codespell-ignore-words.txt is used to be able to define words to be ignored during check with codespell.

Initialising project

To initialise the project after creation we run:

make init

This creates the virtual-environment and installs the dependencies as defined in the pyproject.toml. It also initialises the project as a git-folder and creates the initial commit.

We now activate the poetry-shell to enable the environment:

poetry shell

Attention

Please ensure to always enable the poetry-shell before development using:

poetry shell

The Makefile assumes the environment is activated on usage.

Folder-structure

Following shows code-relevant files for an exampleservice as created using the create_service-tool of fastapi-serviceutils.

exampleservice
├── app
│   ├── config.yml
│   ├── endpoints
│   │   ├── __init__.py
│   │   └── v1
│   │       ├── errors.py
│   │       ├── example.py
│   │       ├── __init__.py
│   │       └── models.py
│   ├── __init__.py
│   └── main.py
├── pyproject.toml
└── tests
    ├── __init__.py
    └── service_test.py
pyproject.toml

The dependencies and definitions like the package-name, version, etc. are defined inside the pyproject.toml. This file is used by Poetry and Dephell. Following the pyproject.toml for our exampleservice:

the pyproject.toml of the exampleservice.
[tool.poetry]
name = "exampleservice"
version = "0.1.0"
description = "Exampleservice to demonstrate usage of fastapi-serviceutils."
authors = ["Dummy User <dummy.user@something.info>"]
readme = "README.md"
include = ["README.md", "app/config.yml"]

[tool.poetry.dependencies]
python = ">=3.7,<4"
fastapi-serviceutils = ">=2"

[tool.poetry.dev-dependencies]
autoflake = ">=1.3"
coverage-badge = ">=1"
flake8 = ">=3.7"
ipython = ">=7.8"
isort = ">=4.3"
jedi = ">=0.14"
neovim = ">=0.3.1"
pre-commit = ">=1.18.3"
pudb = ">=2019.1"
pygments = ">=2.4"
pytest = ">=5"
pytest-asyncio = ">=0.10"
pytest-cov = ">=2"
pytest-xdist = ">=1.30"
sphinx = ">=2"
sphinx-autodoc-typehints = ">=1.6"
sphinx-rtd-theme = ">=0.4.3"
yapf = ">=0.27"

[tool.poetry.extras]
devs = [
    "autoflake", "coverage", "coverage-badge", "flake8", "ipython", "isort",
    "jedi", "neovim", "pre-commit", "pudb", "pygments", "pytest",
    "pytest-asyncio", "pytest-cov", "pytest-xdist", "sphinx",
    "sphinx-autodoc-typehints", "sphinx-rtd-theme", "yapf"
]

[tool.dephell.devs]
from = {format = "poetry", path = "pyproject.toml"}
envs = ["main", "devs"]

[tool.dephell.main]
from = {format = "poetry", path = "pyproject.toml"}
to = {format = "setuppy", path = "setup.py"}
envs = ["main"]
versioning = "semver"

[tool.dephell.lock]
from = {format = "poetry", path = "pyproject.toml"}
to = {format = "poetrylock", path = "poetry.lock"}

[tool.poetry.scripts]
exampleservice = "app.main:main"

[build-system]
requires = ["poetry>=0.12"]
build-backend = "poetry.masonry.api"
app/config.yml

The service is configured using a config-file (config.yml). It is possible to overwrite these setting using environment-variables. An example for the config.yml of the exampleservice is shown below:

config.yml of exampleservice.
service:
    name: 'exampleservice'
    mode: 'devl'
    port: 50001
    description: 'Example tasks'
    apidoc_dir: 'docs/_build'
    readme: 'README.md'
    allowed_hosts:
        - '*'
    use_default_endpoints:
        - alive
        - config
external_resources:
    services: null
    databases: null
    other: null
logger:
    path: './log/EXAMPLESERVICE'
    filename: 'service_{mode}.log'
    level: 'debug'
    rotation: '1 days'
    retention: '1 months'
    format: "<green>{time:YYYY-MM-DD HH:mm:ss.SSS}</green> | <level>{level: <8}</level> | <cyan>{name}</cyan>:<cyan>{function}</cyan>:<cyan>{line}</cyan> [id: {extra[request_id]}] - <level>{message}</level>"
available_environment_variables:
    env_vars:
        - SERVICE__MODE
        - SERVICE__PORT
        - LOGGER__LEVEL
        - LOGGER__PATH
        - LOGGER__FILENAME
        - LOGGER__ROTATION
        - LOGGER__RETENTION
        - LOGGER__FORMAT
    external_resources_env_vars:
        - EXTERNAL_RESOURCES__API__URL
        - EXTERNAL_RESOURCES__API__SCHEMA
    rules_env_vars: []

The config contains four main sections:

  • service

  • external_resources

  • logger

  • available_environment_variables

config: [service]

Inside this section we define the name of the service name. This name is used for the swagger-documentation and extraction of the environment-variables.

The mode define the runtime-mode of the service. This mode can be overwritten with the environment-variable EXAMPLESERVICE__SERVICE__MODE (where 'EXAMPLESERVICE' is the name of the service, meaning if you have a service named SOMETHING the environment-variable would be SOMETHING__SERVICE__MODE).

The port configure the port the service will listen to. This can also be overwritten using the environment variable EXAMPLESERVICE__SERVICE__PORT.

The description is used for the swagger-documentation.

To define the folder where the to find the apidoc to serve by route /api/apidoc/index.html the keyword apidoc_dir is used.

readme defines where to get the readme from to be used as main description for the swagger-documentation at /docs / /redoc.

To controll if only specific hosts are allowed to controll the service we use allowed_hosts. Per default a service would allow all hosts ('*') but this can be customized here in the config.

To define which default endpoints should be included in our service we use use_default_endpoints. Currently we support the default endpoints /api/alive (inside config: 'alive') and /api/config (inside config: 'alive').

config: [external_resources]

Inside this section external dependencies (resources) are defines. A service can depend on other services, databases, remote-connections or files / folders.

Dependencies to other services should be defined inside services. Database connections inside databases (currently only postgres is supported). If any other dependency exist define it in other.

Defined services can be accessed in the code using app.config.external_resources.services or ENDPOINT.config.external_resources.services depending if you are in a main part of the app or inside an endpoint.

Databases are automatically included into the startup and shutdown handlers. You can access the database connection using app.databases['DATABASE_NAME'] or ENDPOINT.databases['DATABASE_NAME'] depending if you are in a main part of the app or inside an endpoint.

config: [logger]

All settings inside this section are default Loguru settings to configure the logger. You can control where to log (path) and how the logfile should be named (filename). Also which minimum level to log (level). To control when to rotate the logfile use rotation. retention defines when to delete old logfiles. The format defines the format to be used for log-messages.

config: [available_environment_variables]

The environment-variables are seperated into three types:

  • env_vars

  • external_resources_env_vars

  • rules_env_vars

Here you can control which environment-variables to use if they are set.

The environment-variables are named like the following: <SERVICENAME>__<MAJOR_SECTION>__<PARAMETER_NAME>. The servicename would be 'EXAMPLESERVICE' in our example. The major-section is one of:

  • 'SERVICE'

  • 'LOGGER'

  • 'EXTERNAL_RESOURCES'

env_vars control the sections service and logger. external_resources_env_vars control the configurations inside the section external_resources. The rules_env_vars should overwrite settings of a ruleset of the service. Such a ruleset defines constants and other rules for the logic of the endpoints. For example a default time-range for your pandas dataframes, etc. Currently this is not implemented, so you would have to use these definitions yourself to overwrite your ruleset-definitions.

app/__init__.py

Inside the __init__.py file of the app we only define the version of our service.

Note

We use semantic-versioning style for services based on fastapi-serviceutils.

This means we have the following version-number: <MAJOR>.<MINOR>.<PATCH>.

For details about semantic-versioning see Semver.

If we bump the version using either dephell bump {major, minor, fix} or poetry version {major, minor, patch}, both the version defined here, and the version defined inside the pyproject.toml will be increased.

__init__.py of app.
__version__ = '0.1.0'
app/main.py

Inside this file we glue all parts of our service together.

Here the app is created which is used either in development inside the function main or in production using uvicorn from command line (or docker-container).

main.py of app.
from pathlib import Path
from typing import NoReturn

from app import __version__
from app.endpoints import ENDPOINTS

from fastapi_serviceutils import make_app

app = make_app(
    config_path=Path(__file__).with_name('config.yml'),
    version=__version__,
    endpoints=ENDPOINTS,
    enable_middlewares=['trusted_hosts',
                        'log_exception'],
    additional_middlewares=[]
)


def main() -> NoReturn:
    import uvicorn
    uvicorn.run(app, host='0.0.0.0', port=app.config.service.port)


if __name__ == '__main__':
    main()

We define where to collect the config-file of the service from, the version of the service and which endpoints and middlewares to use.

app/endpoints/v1/example.py

The following shows the example-endpoint we created:

example.py in version 1. Define the endpoint example.
from app.endpoints.v1.models import Example as Output
from app.endpoints.v1.models import GetExample as Input
from fastapi import APIRouter
from fastapi import Body
from starlette.requests import Request

from fastapi_serviceutils.app import create_id_logger
from fastapi_serviceutils.app import Endpoint

ENDPOINT = Endpoint(router=APIRouter(), route='/example', version='v1')
SUMMARY = 'Example request.'
EXAMPLE = Body(..., example={'msg': 'some message.'})


@ENDPOINT.router.post('/', response_model=Output, summary=SUMMARY)
async def example(request: Request, params: Input = EXAMPLE) -> Output:
    _, log = create_id_logger(request=request, endpoint=ENDPOINT)
    log.debug(f'received request for {request.url} with params {params}.')
    return Output(msg=params.msg)

The ENDPOINT includes the router, route and the version of our endpoint.

Inside the endpoint-function we create a new bound logger with the request-id of the request to allow useful traceback.

Note

Defining endpoints like this allows our worklow with endpoint-versioning and usage of fastapi_serviceutils.endpoints.set_version_endpoints() inside app/endpoints/v1/__init__.py and app/endpoints/__init__.py.

app/endpoints/v1/models.py

The models.py contains models for the endpoints in version 1 of our exampleservice.

For each endpoint we create the model for the input (request) and the model for the output (response).

The models are of type pydantic.BaseModel

models.py of endpoints of version 1.
from pydantic import BaseModel


class GetExample(BaseModel):
    msg: str


class Example(BaseModel):
    msg: str


__all__ = ['Example', 'GetExample']

More complex models could look like the following:

"""
In special cases also an ``alias_generator`` has to be defined.
An example for such a special case is the attribute ``schema`` of
:class:`SpecialParams`. The schema is already an attribute of a BaseModel,
so it can't be used and an alias is required.

To be able to add post-parse-methods the pydantic ``dataclass`` can be
used.
An example for this can be seen in :class:`Complex`.
"""

from pydantic import BaseModel
from pydantic import Schema
from pydantic.dataclasses import dataclass

@dataclass
class Complex:
    """Represent example model with attribute-change of model after init."""
    accuracy: str

    def __post_init_post_parse__(self) -> NoReturn:
        """Overwrite self.accuracy with a mapping as defined below."""
        accuracy_mapping = {
            'something': 's',
            'match': 'm',
        }
        self.accuracy = accuracy_mapping[self.accuracy]

def _alias_for_special_model_attribute(alias: str) -> str:
    """Use as ``alias_generator`` for models with special attribute-names."""
    return alias if not alias.endswith('_') else alias[:-1]

class SpecialParams(BaseModel):
    """Represent example model with special attribute name requiring alias."""
    msg: str
    schema_: str = Schema(None, alias='schema')

    class Config:
        """Required for special attribute ``schema``."""
        alias_generator = _alias_for_special_model_attribute
app/endpoints/v1/__init__.py

Inside this file we include our example-endpoint to the version 1 endpoints.

Note

If additional endpoints are available, these should be added here, too.

The created ENDPOINTS is used inside app/endpoints/__init__.py later.

Note

If we would increase our version to version 2 and we want to change the endpoint example we would add an additional folder inside app/endpoints named v2 and place the new version files there.

__init__.py of v1.
from app.endpoints.v1 import example

from fastapi_serviceutils.app.endpoints import set_version_endpoints

ENDPOINTS = set_version_endpoints(
    endpoints=[example],
    version='v1',
    prefix_template='/api/{version}{route}'
)

__all__ = ['ENDPOINTS']
app/endpoints/__init__.py

In this file we import all endpoint-versions like in this example from app.endpoints.v1 import ENDPOINTS as v1.

Note

If we would have an additional version 2 we would also add from app.endpoints.v2 import ENDPOINTS as v2.

Then we use fastapi_serviceutils.endpoints.set_version_endpoints() with the latest version endpoints to create LATEST.

Note

If we would have version 2, too we would replace parameter endpoints with v2.

The ENDPOINTS is a list of all available versions.

These ENDPOINTS are used inside app/main.py to include them to the service.

__init__.py of endpoints.
from app.endpoints.v1 import ENDPOINTS as v1

from fastapi_serviceutils.app.endpoints import set_version_endpoints

LATEST = set_version_endpoints(
    endpoints=v1,
    version='latest',
    prefix_template='{route}'
)

ENDPOINTS = LATEST + v1

__all__ = ['ENDPOINTS']
tests

The tests for the exampleservice are using Pytest. We also used the testutils of fastapi-serviceutils. An example for simple endpoint tests of our exampleservice:

tests/service_test.py
import pytest
from app.main import app

from fastapi_serviceutils.app.service_config import Config
from fastapi_serviceutils.utils.tests.endpoints import json_endpoint


def test_endpoint_example():
    json_endpoint(
        application=app,
        endpoint='/api/v1/example/',
        payload={'msg': 'test'},
        expected={'msg': 'test'}
    )


@pytest.mark.parametrize(
    'endpoint, status_code',
    [
        ('/api/v1/example',
         307),
        ('/api/',
         404),
        ('/api/v1/',
         404),
        ('/api/v1/example/',
         200),
    ]
)
def test_endpoint_invalid(endpoint, status_code):
    json_endpoint(
        application=app,
        endpoint=endpoint,
        status_code=status_code,
        payload={'msg': 'test'}
    )

External resources

Databases
config.yml

If we use a database in our service we declare the connection info in the config.yml of the service like the following:

app/config.yml
...
external_resources:
    services: null
    databases:
        userdb:
            dsn: 'postgresql://postgres:1234@localhost:5434/userdb'
            databasetype: 'postgres'
            min_size: 5
            max_size: 20
    other: null
...

For each database we want to use in our service, we define a new item inside databases. The key will be the name of our database. The connection itself is defined as dsn. The databasetype defines the type of the database we are using. This setting is for future releases of fastapi-serviceutils. Currently we only support postgres and this setting has no effect. min_size and max_size define the minimum and maximum amount of connections to open to the database.

app/endpoints/v1/dbs.py

Inside the module dbs.py we define our datatables like the following:

app/endpoints/v1/dbs.py
from sqlalchemy import Boolean
from sqlalchemy import Column
from sqlalchemy import insert
from sqlalchemy import Integer
from sqlalchemy import String
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

class User(Base):
    __tablename__ = 'users'

    id = Column(Integer, primary_key=True, index=True)
    email = Column(String, unique=True, index=True)
    password = Column(String)
app/endpoints/v1/models.py

As for each endpoint we declare the input- and output-models we are using in our new endpoints like the following:

app/endpoints/v1/models.py
from pydantic import BaseModel

class InsertUser(BaseModel):
    email: str
    password: str

class Inserted(BaseModel):
    msg: bool = True

class User(BaseModel):
    id: int
    email: str
    password: str
app/endpoints/v1/insert_user.py
app/endpoints/v1/insert_user.py
from fastapi import Body
from fastapi import APIRouter
from fastapi_serviceutils.app import Endpoint
from fastapi_serviceutils.app import create_id_logger
from sqlalchemy import insert

from app.endpoints.v1.dbs import User
from app.endpoints.v1.models import InsertUser as Input
from app.endpoints.v1.models import Inserted as Output

ENDPOINT = Endpoint(router=APIRouter(), route='/insert_user', version='v1')
SUMMARY = 'Example request.'
EXAMPLE = Body(
    ...,
    example={
        'email': 'dummy.user@something.info'
        'password': 'an3xampleP4ssword'
    }
)

@ENDPOINT.router.post('/', response_model=Output, summary=SUMMARY)
async def insert_user(params: Input = EXAMPLE, request: Request) -> Output:
    _, log = create_id_logger(request=request, endpoint=ENDPOINT)
    log.debug(f'received request for {request.url} with params {params}.')
    database = app.databases['userdb'].dbase
    async with database.transaction():
        query = insert(User).values(
            email=params.email,
            password=params.password
        )
        await database.execute(query)
    return Output()
app/endpoints/v1/get_users.py
app/endpoints/v1/get_users.py
from fastapi import Body
from fastapi import APIRouter
from fastapi_serviceutils.app import Endpoint
from fastapi_serviceutils.app import create_id_logger

from app.endpoints.v1.dbs import User
from app.endpoints.v1.models import User as Output

ENDPOINT = Endpoint(router=APIRouter(), route='/get_users', version='v1')
SUMMARY = 'Example request.'

@ENDPOINT.router.post('/', response_model=Output, summary=SUMMARY)
async def get_users(request: Request) -> List[Output]:
    _, log = create_id_logger(request=request, endpoint=ENDPOINT)
    log.debug(f'received request for {request.url}.')
    database = app.databases['userdb'].dbase
    async with database.transaction():
        users = await database.fetch_all(User.__table__.select())
    return users
app/endpoints/v1/__init__.py

Finally we include these endpoints to our ENDPOINTS.

__init__.py
from fastapi_serviceutils.endpoints import set_version_endpoints

from app.endpoints.v1 import get_users
from app.endpoints.v1 import insert_user

ENDPOINTS = set_version_endpoints(
    endpoints=[get_users, insert_user],
    version='v1',
    prefix_template='/api/{version}{route}'
)

__all__ = ['ENDPOINTS']

The rest of our service, like the main.py, the __init__.py files of the modules, etc. have the same content as described in exampleservice.

Services

If we need to call external services we first have to declare the service inside the config.yml like the following:

app/config.yml
...
external_resources:
    services:
        testservice:
            url: http://someserviceurl:someport
            servicetype: rest
    databases: null
    other: null
...
app/endpoints/v1/models.py
from pydantic import BaseModel

class CallExternalService(BaseModel):
    street: str
    street_number: str
    zip_code: str
    city: str
    country: str

class ExternalServiceResult(BaseModel):
    longitude: str
    latitude: str
app/endpoints/v1/external_service.py
from fastapi import APIRouter
from fastapi import Body
from fastapi_serviceutils.app import Endpoint
from fastapi_serviceutils.app import create_id_logger
from fastapi_serviceutils.utils.external_resources.services import call_service
from starlette.requests import Request

from app.endpoints.v1.models import CallExternalService as Input
from app.endpoints.v1.models import ExternalServiceResult as Output

ENDPOINT = Endpoint(router=APIRouter(), route='/use_service', version='v1')
SUMMARY = 'Example request using an external service.'
EXAMPLE = Body(
    ...,
    example={
        'street': 'anystreetname',
        'street_number': '42',
        'city': 'anycity',
        'country': 'gallifrey'
    }
)

@ENDPOINT.router.post('/', response_model=Output, summary=SUMMARY)
async def use_service(params: Input = EXAMPLE, request: Request) -> Output:
    data_to_fetch = {
        'street': params.street,
        'auth_key': 'fnbkjgkegej',
        'street_number': params.street_number,
        'city': params.city,
        'country': params.country
    }
    return await call_service(
        url=app.databases['testservice'].url,
        params=data_to_fetch,
        model=ExternalServiceResult
    )

Helpers

create_service

Create new service following the structure as described in the fastapi_serviceutils documentation. Using Cookiecutter to create the new folder.

usage: create_service [-h] -n SERVICE_NAME -p SERVICE_PORT -a AUTHOR -e
                      AUTHOR_EMAIL -ep ENDPOINT -o OUTPUT_DIR

create new service based on fastapi using fastapi_serviceutils.

optional arguments:
  -h, --help            show this help message and exit
  -n SERVICE_NAME, --service_name SERVICE_NAME
                        the name of the service to create. ATTENTION: only
                        ascii-letters, "_" and digits are allowed. Must not
                        start with a digit!
  -p SERVICE_PORT, --service_port SERVICE_PORT
                        the port for the service to listen.
  -a AUTHOR, --author AUTHOR
                        the name of the author of the service.
  -e AUTHOR_EMAIL, --author_email AUTHOR_EMAIL
                        the email of the author of the service.
  -ep ENDPOINT, --endpoint ENDPOINT
                        the name of the endpoint for the service to create.
                        ATTENTION: only lower ascii-letters, "_" and digits
                        are allowed. Must not start with a digit!
  -o OUTPUT_DIR, --output_dir OUTPUT_DIR
Makefile

Usual tasks during development are wrapped inside the Makefile. This contains updating of the environment, creation of the docs, etc.

Helpers for development of fastapi_serviceutils.

  Usage:

    make <target> [flags...]

  Targets:

    check      Run all checks defined in .pre-commit-config.yaml.
    clean      Clean the working directory from temporary files and caches.
    doc        Create sphinx documentation for the project.
    docs       Create sphinx documentation for the project.
    finalize   Finalize the main env.
    help       Show the help prompt.
    info       Show info about current project.
    init       Initialize project
    tests      Run tests using pytest.
    update     Update environments based on pyproject.toml definitions.

  Flags:



  Note:
      This workflow requires the following programs / tools to be installed:
      - poetry
      - dephell
      - pyenv
tmuxp

For a predefined development environment the .tmuxp.yml configuration can be used to create a Tmux-session (using Tmuxp) with a window including three panels:

  • one panel for editing files

  • one panel running the service

  • one panel running the tests

Run the following command to create the tmux-session:

tmuxp load .

Deployment

For more detailed information about deployment of fastapi-based services see FastAPI deployment

Services based on fastapi-serviceutils can be easily deployed inside a docker-container.

Before deployment you need to:

  • update the dependencies

  • run all tests

  • create the current requirements.txt

  • ensure the docker-compose.yml is defined correctly including the environment-variables

To run these tasks run:

make finalize

To run the service using docker-compose customize the docker-compose.yml and run:

sudo docker-compose up -d
Basics
Docker

The basic Dockerfile should look like:

FROM tiangolo/uvicorn-gunicorn-fastapi:python3.7

COPY requirements.txt ./

RUN pip install -r requirements.txt

COPY . /app
Docker-compose

The service can be deployed with Docker compose using the Docker compose file:

an example for a docker-compose.yml for a service using fastapi_serviceutils.
version: '3.7'

services:
    <SERVICENAME>:
        build:
            context: .
            dockerfile: Dockerfile
        image: <SERVICENAME>
        ports:
            - "<SERVICE_PORT>:80"
        environment:
            - <SERVICENAME>_SERVICE__MODE="prod"
            - ...
        volumes:
            - type: bind
              source: <LOGFOLDER_ON_HOST>
              target: <LOGFOLDER_INSIDE_DOCKER_CONTAINER>
Environment-variables

Setting environment-variables overwrites the default values defined in the config.

Please ensure to use the environment-variables (Environment variable) if you want to overwrite some default-settings of the service.

The environment-variables to use should be defined inside the config.yml. Set the values of the environment-variables inside the docker-compose.yml.

Development

Getting Started

After cloning the repository the development environment can be initialized using:

make init

This will create the dev environment fastapi_serviceutils/dev. Activate it.

Note

Make sure to always activate the environment when you start working on the project in a new terminal using

poetry shell

To update dependencies and poetry.lock:

make update

This also creates requirements.txt to be used for Docker.

Dependency management

We use Poetry including the dependency definition inside the pyproject.toml and python-venv for environment management. Additionally we use Dephell and make for easier workflow.

dependency-management files
<SERVICENAME>
├── ...
├── poetry.lock
├── pyproject.toml
├── .python-version
└── ...
  • pyproject.toml: stores what dependencies are required in which versions. Required by Dephell and Poetry.

  • poetry.lock: locked definition of installed packages and their versions of currently used devs-environment. Created by Poetry using make init, make update, make tests or make finalize.

  • .python-version: the version of the python-interpreter used for this project. Created by python-venv using make init, required by Poetry and Dephell.

Testing

All tests are located inside the folder tests. Tests for a module should be names like <MODULE_NAME>_test.py.

Note

For often used functions and workflows during testing the functions and classes inside fastapi_serviceutils.utils.tests can be used.

To run the tests run:

make tests

A HTML coverage report is automatically created in the htmlcov directory.

See also

For additional information how to test fastapi-applications:

For information how to test async functions:

Documentation

The project’s developer documentation is written using Sphinx.

The documentation sources can be found in the docs subdirectory. They are using restructuredText-files.

The API-documentation is auto-generated from the docstrings of modules, classes, and functions. For documentation inside the source-code the Google docstring standard is used.

To generate the documentation, run

make docs

The created documentation (as html files) will be inside the docs/_build directory.

There is also a swagger-documentation to be used for users of the service. After starting the service the documentation can be viewed at:

The sphinx-documentation can be viewed after service-started and docs created at http://0.0.0.0:<SERVICE_PORT>/apidoc/index.html.

documentation related files
 <SERVICENAME>
 ├── ...
 ├── docs
 │   ├── _build
 │   │   └── ...
 │   ├── conf.py
 │   ├── development.rst
 │   ├── index.rst
 │   ├── <ADDITIONAL_DOCUMENTATION_PAGE>.rst
 │   └── _static
 │       ├── coverage.svg
 │       └── logo.png
 ├── ...
 ├── README.md
 └── ...

fastapi_serviceutils package

Subpackages

fastapi_serviceutils.app package
Subpackages
fastapi_serviceutils.app.endpoints package
Subpackages
fastapi_serviceutils.app.endpoints.default package
Submodules
fastapi_serviceutils.app.endpoints.default.alive module
fastapi_serviceutils.app.endpoints.default.config module
fastapi_serviceutils.app.endpoints.default.models module
fastapi_serviceutils.app.handlers package
fastapi_serviceutils.app.middlewares package
Submodules
fastapi_serviceutils.app.logger module
fastapi_serviceutils.app.service_config module
fastapi_serviceutils.cli package
Submodules
fastapi_serviceutils.cli.create_service module
fastapi_serviceutils.utils package
Subpackages
fastapi_serviceutils.utils.docs package
Submodules
fastapi_serviceutils.utils.docs.apidoc module
fastapi_serviceutils.utils.external_resources package
Submodules
fastapi_serviceutils.utils.external_resources.dbs module
fastapi_serviceutils.utils.external_resources.services module
fastapi_serviceutils.utils.tests package
Submodules
fastapi_serviceutils.utils.tests.endpoints module