A small Flask REST API app written to a spec.

FlaskREST.py

from flask import Flask, jsonify, request
import uuid
import sqlite3
from flask import g

DATABASE = '/tmp/database.db'

app = Flask(__name__)


def get_db():
    db = getattr(g, '_database', None)
    if db is None:
        db = g._database = sqlite3.connect(DATABASE)
    return db


@app.teardown_appcontext
def close_connection(exception):
    db = getattr(g, '_database', None)
    if db is not None:
        db.close()


def query_db(query, args=(), one=False):
    cur = get_db().execute(query, args)
    rv = cur.fetchall()
    cur.close()
    return (rv[0] if rv else None) if one else rv


def init_db():
    with app.app_context():
        db = get_db()
        with app.open_resource('schema.sql', mode='r') as f:
            db.cursor().executescript(f.read())
        db.commit()


@app.route('/test/api/register', methods=['GET'])
def create_app_id():
    a = uuid.uuid4()
    reg_token = a.hex
    new_id = {
        'app_id': reg_token
    }

    return jsonify(app_id=reg_token)


@app.route('/test/api/store/<reg_token>', methods=['POST'])
def store_data(reg_token):
    db = get_db()
    app_id = query_db('select id from application where app_id = ?', [reg_token], one=True)

    if app_id:

        print app_id[0]
    else:
        print "Nothing found"

    ''' If the app_id is not in the database, save it and generate an id for the pairs table'''
    if not app_id:
        print reg_token
        db.execute('INSERT INTO application (app_id) VALUES (?)', [reg_token])
        print "success"
        db.commit()

        app_id = query_db('select id from application where app_id = ?', [reg_token], one=True)

        ''' Then save the key/pair data'''
        data_record = [(request.json['key_name']),
                   (request.json['val']),
                    app_id[0],
        ]

        print data_record
        db.execute('INSERT INTO pairs(key_name, val, app) VALUES (?,?,?)', data_record)
        db.commit()
        return "Inserted new application id and key/pair data into database"

    else:
        '''If the app_id is in the database, save the key/pair value against it's id'''

        data_record = [(request.json['key_name']),
                   (request.json['val']),
                    app_id[0],
        ]

        print data_record
        db.execute('INSERT INTO pairs(key_name, val, app) VALUES (?,?,?)', data_record)
        db.commit()
        return "Inserted key/pair data for existing app_id in database"


@app.route('/test/api/retrieve/<reg_token>', methods=['GET'])
def get_data_values(reg_token):

    key = request.args.get('key_name')
    print key
    app_id = reg_token
    print app_id
    db = get_db()
    identifier = query_db('select id from application where app_id=?', [app_id], one=True)

    ''' If the key_name is found '''
    key_exists = query_db('select key_name from pairs where key_name=?', [key], one=True)
    if key_exists:
        print "Key exists"

        print identifier[0]
        if not identifier:
            return "Application id not found in database"

        ''' Return value for key specified '''
        print key
        data_record=[
            key,
            identifier[0],
        ]

        val = query_db('SELECT val FROM pairs WHERE key_name=(?) AND app=(?)', data_record, one=True)
        return jsonify(key_value=val)
    else:
        print "Key was not found"
        ''' Return all key/value pairs for identified application '''
        for row in query_db('SELECT key_name, val FROM pairs WHERE app=?', [identifier[0]]):
            return jsonify(row=row)

    return "Successfully finished"

if __name__ == '__main__':
    app.run()