An elixir client for the Youtube API (v3).
If available in Hex, the package can be installed
by adding exyt to your list of dependencies in mix.exs:
def deps do
[{:exyt, "~> 0.2.0"}]
endGoogle's Youtube API uses OAuth2 to authenticate a user with its services. This requires first to have a set of credentials with which an authorization code can be obtained, where the user allows the application to be connected with the Google account. Once the user permits the application to connect with Google, the authorization code can then be used to fetch an access token. All endpoints of the Youtube API accept the access token to return results.
Google's authentication API requires to have a client_id and client_secret, both can be obtained on Google's Credentials page. On this page create OAuth client ID credentials. Once successfully created the credentials can be displayed. There are two ways to use these credentials with this library.
The recommended solution is to set application variables in the configuration file. Please note these credentials should stay outside of version control.
# config/prod.exs
use Mix.Config
config :exyt,
client_id: "123456…",
client_secret: "abcdef…",
redirect_uri: "http://example.com/callback"With these settings in place the library picks up the configuration variables automatically. Instead of defining the credentials directly a more common approach is to use environment variables. For example to set environment variables via terminal:
export YOUTUBE_CLIENT_ID="123456…"
export YOUTUBE_CLIENT_SECRET="abcdef…"Then the configuration file can be part of version control and just reads the environment variables:
# config/config.exs
use Mix.Config
config :exyt,
client_id: System.get_env["YOUTUBE_CLIENT_ID"],
client_Secret: System.get_env["YOUTUBE_CLIENT_SECRET"],
redirect_uri: "http://example.com/callback"An alternative version is to set client_id and client_secret directly when creating the Exyt.Client struct:
iex> client = Exyt.Client.new(client_id: "123456…", client_secret: "abcdef…", redirect_uri: "…")
%Exyt.Client{client_id: "123456…", client_secret: "abcdef…", redirect_uri: "…", …}Once the credentials are configured, the first step in the OAuth2 process is to open Google's authorization page. For more information on the process of getting an access token see Using OAuth2 for Web Server Applications To provide all necessary settings as query arguments a utility function can be used to generate such a URL.
In case the required settings are configured as shown above, simply call:
Exyt.Client.authorize_url()
"https://accounts.google.com/o/oauth2/auth?client_id=123456…&redirect_uri=http%3A%2F%2Fexample.com%2Fcallback&…"The returned URL can be used for example to redirect a web application to Google's authorization page. The user then can select the Google account to connect the application with. Once confirmed Google will call back the page specified via redirect_uri setting as configured on the Credentials page. The authentication code is provided as query parameter and needs to be handled by the application.
An example callback may look like:
"http://example.com/callback?code=4%2FABCDEF…&state=state_parameter_passthrough_value&…"
The application needs to read the query parameter code. With the help of this authentication code an access token can be obtained. With the above client variable in place another function can be used to fetch an access token:
code = "4\ABCDEF…"
case Exyt.Auth.access_token(client, code) do
{:ok, token} ->
IO.puts "Access token: #{inspect(token.access_token)}"
{:error, message} ->
IO.puts "Failed to fetch access token: #{message}"
endAlternatively call Exyt.Auth.access_token!\2 to fetch the token directly.
The following list shows which API endpoints this library supports.
References
- https://developers.google.com/youtube/v3/guides/auth/server-side-web-apps
- https://blog.timekit.io/google-oauth-invalid-grant-nightmare-and-how-to-fix-it-9f4efaf1da35
The following libraries are used