Overview


Client Object

Methods

The client singleton is the main object which is used to request data from the Yahoo Finance API servers. It has three methods: the get method, which is used to make a single request, the batch_get helper method, which is used to schedule multiple requests with one call, and the get_all helper method, which requests data about a single symbol from all symbol-specific endpoints at once.

You can get the list of valid endpoints and their arguments by running the server and reading the Swagger documentation. To convert the servers endpoint path param names for use with the client object, just omit the / character from the beginning of the endpoint name: /company_overview becomes company_overview.

Decorators

The client object has a single decorator named session, which opens a session to the Yahoo Finance API servers and inspects the concurrency mode of your program to adjust its behaviour accordingly. This enables YFrake to work in async and sync (threaded) modes out-of-the-box.

A function or a coroutine must be decorated with this decorator before any calls to the client methods are made. Calls to the client methods do not have to take place inside the same function or coroutine which was decorated.

For simplicity’s sake, it is recommended to decorate the main function or coroutine of your program, so the session is opened on program start and closed when the program ends, but in essence any function or a coroutine can be used, as long as the before-mentioned considerations are taken into account.

The best practice is to have your program activate the decorator only once, because repeatedly opening and closing the session will kill your performance.

Note: On Windows machines, the decorator automatically sets the asyncio event loop policy to WindowsSelectorEventLoopPolicy, because the default WindowsProactorEventLoopPolicy does not work correctly. This automatic selection works only when the decorated coroutine of your program is the main coroutine, which gets passed into the asyncio.run() function.


ClientResponse Object

Instances of this object are returned by the client.get method. It handles the request and contains the response from the Yahoo Finance API servers in three properties: endpoint, error and data. It has methods to (a)wait for the response and to check its completion status and also two properties, event and future, to access the low-level internals of the ClientResponse object.


Async- and ThreadResults Object

Instances of these objects, which are returned by the client.batch_get and the client.get_all methods, are a list-like containers of ClientResponse objects with additional functionality attached on top.

There are two kinds of results objects: AsyncResults and ThreadResults. Which one is returned depends on the concurrency mode of the program. AsyncResults is returned when the program is running in async mode and the ThreadResults is returned when the program is running in sync (threaded) mode.

The results objects can be used with the len() and list() functions and the subscript operator []. They have methods to (a)wait for the requests and to check their completion statuses and also generators to iterate over the ClientResponse objects in a for or an async for loop. These generators guarantee that the objects which they yield into the for loop have finished their request to the servers.

You can also loop over a results object with for resp in results, but the returned objects are not guaranteed to be in a finished state, unless you have specifically (a)waited the results object beforehand.