reddit-clone

The flask-app allows any user to create a topic and upvote/downvote any topic.

Setup

pip install -r requirements.txt

Steps to run

python runserver.py

Run test cases

pytest --setup-show tests/

Key features:

Allow user creation by unique id
Allow an existing user to create a topic
Allow an existing user to upvote/downvote a topic
Returns top 20 topics by upvotes

Constraints

All the data is stored in-memory, so app restart will remove previously created data
User creation can only be done on a unique id
Topic length should be less than 255 characters.
Topic creation/upvote/downvote can be done by existing user.
A user can upvote/downvote a topic any number of times.

Error log

Logs will be generated in a file service.log. For any incorrect output, please check the error log.

In-memory database design

There is one DataStore object that stores all the data about users, topics, upvotes and downvotes.
Users can be created using unique id. A hash_map stores all the users with key as user_id and value as user_object.
Topics are stored in a hash_map. For each new topic, a unique uuid is generated and is stored in a hash_map with key as id and value as topic content.
Upvotes and downvotes are stored separately using Counter which keeps the count of upvotes/downvotes against topic_id.
Top 20 topics are displayed using Counter inbuilt function most_common.

UI Design

The user should login/signup first before creating a topic/upvote/downvote.
Logout user will be redirected to login page if they go to login/upvote/downvote/signout page.
Only user_id is required for signup/login page.
Home page displays all the topics sorted by upvotes.
All topics page displays all the topics.

Curl Requests:

Create user

curl -i -X POST
-H "Accept:application/json"
-H "Content-Type:application/json"
-d
'{"user_id": }'
'https://reddit-clone1.herokuapp.com/signup'

e.g.

curl -i -X POST
-H "Accept:application/json"
-H "Content-Type:application/json"
-d
'{"user_id": "charul"}'
'https://reddit-clone1.herokuapp.com/signup'

Create topic

curl -i -X POST
-H "Accept:application/json"
-H "Content-Type:application/json"
-d
'{"user_id": , "content": }'
'https://reddit-clone1.herokuapp.com/topic'

e.g. curl -i -X POST
-H "Accept:application/json"
-H "Content-Type:application/json"
-d
'{"user_id": "charul", "content": "test"}'
'https://reddit-clone1.herokuapp.com/topic'

Upvote a topic

curl -i -X POST
-H "Accept:application/json"
-H "Content-type:application/json"
-d
'{"user_id": }'
'https://reddit-clone1.herokuapp.com/upvote/'

e.g. curl -i -X POST
-H "Accept:application/json"
-H "Content-type:application/json"
-d
'{"user_id": "a1"}'
'https://reddit-clone1.herokuapp.com/upvote/0100de81-b3e2-4785-99d2-29062b699c41'

Downvote a topic

curl -i -X POST
-H "Accept:application/json"
-H "Content-type:application/json"
-d
'{"user_id": }'
'https://reddit-clone1.herokuapp.com/downvote/'

e.g. curl -i -X POST
-H "Accept:application/json"
-H "Content-type:application/json"
-d
'{"user_id": "a1"}'
'https://reddit-clone1.herokuapp.com/downvote/0100de81-b3e2-4785-99d2-29062b699c41'

Get a topic by id

curl -i -X GET
-H "Accept:application/json"
'https://reddit-clone1.herokuapp.com/topic/'