Metadata-Version: 1.1
Name: fdk
Version: 0.0.11
Summary: Function Developer Kit for Python
Home-page: https://fnproject.github.io
Author: Denis Makogon
Author-email: denys.makogon@oracle.com
License: UNKNOWN
Description-Content-Type: UNKNOWN
Description: FN development kit for Python
        =============================
        
        Purpose of this library to provide simple interface to parse HTTP 1.1 requests represented as string
        
        Following examples are showing how to use API of this library to work with streaming HTTP requests from Fn service.
        
        Handling Hot HTTP Functions
        ---------------------------
        
        A main loop is supplied that can repeatedly call a user function with a series of HTTP requests.
        In order to utilise this, you can write your `app.py` as follows:
        
        ```python
        import fdk
        
        from fdk import response
        
        
        def handler(context, data=None, loop=None):
            return response.RawResponse(
                context,
                status_code=200,
                headers={},
                response_data=data.readall()
            )
        
        
        if __name__ == "__main__":
            fdk.handle(handler)
        
        ```
        
        Automatic input coercions
        ------------------------------
        
        Decorators are provided that will attempt to coerce input values to Python types.
        Some attempt is made to coerce return values from these functions also:
        
        ```python
        import fdk
        
        
        @fdk.coerce_input_to_content_type
        def handler(context, data=None, loop=None):
            """
            body is a request body, it's type depends on content type
            """
            return data
        
        
        if __name__ == "__main__":
            fdk.handle(handler)
        
        ```
        
        Working with async automatic input coercions
        -------------------------------------------------
        
        Latest version supports async coroutines as a request body processors:
        ```python
        import asyncio
        import fdk
        
        from fdk import response
        
        
        @fdk.coerce_input_to_content_type
        async def handler(context, data=None, loop=None):
            headers = {
                "Content-Type": "text/plain",
            }
            return response.RawResponse(
                context,
                status_code=200,
                headers=headers,
                response_data="OK"
            )
        
        
        if __name__ == "__main__":
            loop = asyncio.get_event_loop()
            fdk.handle(handler, loop=loop)
        
        ```
        As you can see `app` function is no longer callable, because its type: coroutine, so we need to bypass event loop inside
        
        Handling Hot JSON Functions
        ---------------------------
        
        A main loop is supplied that can repeatedly call a user function with a series of HTTP requests.
        In order to utilise this, you can write your `app.py` as follows:
        
        ```python
        import fdk
        
        
        def handler(context, data=None, loop=None):
            return data
        
        
        if __name__ == "__main__":
            fdk.handle(handler)
        
        ```
        
        Working with async Hot JSON Functions
        -------------------------------------
        
        Latest version supports async coroutines as a request body processors:
        ```python
        import asyncio
        
        import fdk
        
        
        async def handler(context, data=None, loop=None):
            return data
        
        
        if __name__ == "__main__":
            loop = asyncio.get_event_loop()
            fdk.handle(handler, loop=loop)
        
        ```
        
        Applications powered by Fn: Concept
        -----------------------------------
        
        FDK is not only about developing functions, but providing necessary API to build serverless applications
        that look like nothing but classes with methods powered by Fn.
        
        ```python
        import requests
        
        from fdk.application import decorators
        
        
        @decorators.fn_app
        class Application(object):
        
            def __init__(self, *args, **kwargs):
                pass
        
            @decorators.with_fn(fn_image="denismakogon/os.environ:latest")
            def env(self, fn_data=None):
                return fn_data
        
            @decorators.with_fn(fn_image="denismakogon/py-traceback-test:0.0.1",
                                fn_format="http")
            def traceback(self, fn_data=None):
                return fn_data
        
            @decorators.fn(fn_type="sync")
            def square(self, x, y, *args, **kwargs):
                return x * y
        
            @decorators.fn(fn_type="sync", dependencies={
                "requests_get": requests.get
            })
            def request(self, *args, **kwargs):
                requests_get = kwargs["dependencies"].get("requests_get")
                r = requests_get('https://api.github.com/events')
                r.raise_for_status()
                return r.text
        
        
        if __name__ == "__main__":
            app = Application(config={})
        
            res, err = app.env()
            if err:
                raise err
            print(res)
        
            res, err = app.traceback()
            if err:
                raise err
            print(res)
        
            res, err = app.square(10, 20)
            if err:
                raise err
            print(res)
        
            res, err = app.request()
            if err:
                raise err
            print(res)
        
        ```
        In order to identify to which Fn instance code needs to talk set following env var:
        
        ```bash
            export API_URL = http: // localhost: 8080
        ```
        with respect to IP address or domain name where Fn lives.
        
        
        Applications powered by Fn: supply data to a function
        -----------------------------------------------------
        
        At this moment those helper - decorators let developers interact with Fn - powered functions as with regular class methods.
        In order to pass necessary data into a function developer just needs to do following
        ```python
        
        if __name__ == "__main__":
            app = Application(config={})
        
            app.env(keyone="blah", keytwo="blah", somethingelse=3)
        
        ```
        Key - value args will be turned into JSON instance and will be sent to a function as payload body.
        
        
        Applications powered by Fn: working with function's result
        ----------------------------------------------------------
        
        In order to work with result from function you just need to read key - value argument `fn_data`:
        ```python
            @decorators.with_fn(fn_image="denismakogon/py-traceback-test:0.0.1",
                                fn_format="http")
            def traceback(self, fn_data=None):
                return fn_data
        ```
        
        Applications powered by Fn: advanced serverless functions
        ---------------------------------------------------------
        
        Since release v0.0.3 developer can consume new API to build truly serverless functions
        without taking care of Docker images, application, etc.
        
        ```python
            @decorators.fn(fn_type="sync")
            def square(self, x, y, *args, **kwargs):
                return x * y
        
            @decorators.fn(fn_type="sync", dependencies={
                "requests_get": requests.get
            })
            def request(self, *args, **kwargs):
                requests_get = kwargs["dependencies"].get("requests_get")
                r = requests_get('https://api.github.com/events')
                r.raise_for_status()
                return r.text
        ```
        
        Each function decorated with `@decorator.fn` will become truly serverless and distributed.
        So, how it works?
        
            * A developer writes function
            * FDK(Fn - powered app) creates a recursive Pickle v4.0 with 3rd - party dependencies
            * FDK(Fn - powered app) transfers pickled object to a function based on Python3 GPI(general purpose image)
            * FDK unpickles function and its 3rd - party dependencies and runs it
            * Function sends response back to Fn - powered application function caller
        
        So, each CPU - intensive functions can be sent to Fn with the only load on networking(given example creates 7kB of traffic between app's host and Fn).
        
        
        Applications powered by Fn: exceptions
        --------------------------------------
        
        Applications powered by Fn are following Go - like errors concept. It gives you full control on errors whether raise them or not.
        ```python
            res, err = app.env()
            if err:
                raise err
            print(res)
        
        ```
        Each error is an instance fn `FnError` that encapsulates certain logic that makes hides HTTP errors and turns them into regular Python - like exceptions.
        
        TODOs
        -----
        
            - generic response class
            - use fdk.headers.GoLikeHeaders in http
        
        
Platform: UNKNOWN
Classifier: Intended Audience :: Information Technology
Classifier: Intended Audience :: System Administrators
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Operating System :: POSIX :: Linux
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
