Example to use spotipy in an API, closes #287

FAQ.md

@@ -4,6 +4,10 @@
 
 spotipy can only return fields documented on the Spotify web API https://developer.spotify.com/documentation/web-api/reference/
 
+### How to use spotipy in an API?
+
+Check out [this example Flask app](examples/app.py)
+
 ### Incorrect user
 
 Error:

examples/app.py

@@ -0,0 +1,56 @@
+"""
+Prerequisites
+
+    pip3 install spotipy Flask Flask-Session
+
+    export SPOTIPY_CLIENT_ID=client_id_here
+    export SPOTIPY_CLIENT_SECRET=client_secret_here
+    // on Windows, use `SET` instead of `export`
+
+Run app.py
+
+    python3 -m flask run --port=8080
+"""
+
+import os
+from flask import Flask, session, request, redirect
+from flask_session import Session
+import spotipy
+
+app = Flask(__name__)
+app.config['SECRET_KEY'] = os.urandom(64)
+app.config['SESSION_TYPE'] = 'filesystem'
+
+Session(app)
+
+auth_manager = spotipy.oauth2.SpotifyOAuth()
+spotify = spotipy.Spotify(auth_manager=auth_manager)
+
+
+@app.route('/')
+def index():
+    if request.args.get("code"):
+        session['token_info'] = auth_manager.get_access_token(request.args["code"])
+        return redirect('/')
+
+    if not session.get('token_info'):
+        auth_url = auth_manager.get_authorize_url()
+        return f'<h2><a href="{auth_url}">Sign in</a></h2>'
+
+    return f'<h2>Hi {spotify.me()["display_name"]}, ' \
+           f'<small><a href="/sign_out">[sign out]<a/></small></h2>' \
+           f'<a href="/playlists">my playlists</a>'
+
+
+@app.route('/sign_out')
+def sign_out():
+    session.clear()
+    return redirect('/')
+
+
+@app.route('/playlists')
+def playlists():
+    if not session.get('token_info'):
+        return redirect('/')
+    else:
+        return spotify.current_user_playlists()