A twitter-toy-clone backend using Python and Redis


Keywords
redis, twitter, python3, 6, python36
License
Apache-2.0
Install
pip install pytwis==0.4.1

Documentation

pytwis

Build Status

This package contains two modules pytwis and pytwis_clt where

  • pytwis is a Twitter-toy-clone backend using Redis;
  • pytwis_clt is a command-line tool which uses pytwis to interact with the Redis database of the Twitter-toy clone.

To install this package,

$ pip install pytwis

Note that

  • This package requires Python 3.6 and later since it depends on Python 3.6 built-in module secrets.
  • There is a breaking change introduced in v0.4.0: the salted password hashes are stored in the Redis database instead of the plain-text passwords, so the Redis database created by the version before v0.4.0 won't work with the version v0.4.0 and after unless a manual database migration is done.

Table of Contents

1. pytwis

1.1 Introduction

This module implements the backend for a simplified Twitter clone based on Redis. We follow the Redis tutorial (https://redis.io/topics/twitter-clone) to design the data layout of the Redis database.

It supports the following features:

  • Register new users
  • Log in/out
  • Change user password
  • Get user profile
  • Post tweets
  • Follower/Following
  • General timeline for anonymous user
  • User timeline
  • Get tweets posted by one user

TODOs:

  • Search users
  • Delete a user
  • Recover user password
  • #hashtags
  • @mentions
  • Retweets
  • Replies
  • Conversations
  • Edit/Delete tweets
  • And more

1.2 Sample usage

Below is a sample usage of this module. You can find a more detailed example in the module pytwis_clt.

import pytwis

# Connect to the Redis server by creating a Pytwis instance. 
twis = pytwis.Pytwis()

# You may specify the hostname, the port, the database index, and the password of the Redis server as keyword arguments.
twis = pytwis.Pytwis(hostname='127.0.0.1', port=6379, db=0, password='password')

# For all the following operations, if succeeded is False, check result['error'] for the error string.

# Register a new user.
succeeded, result = twis.register('username', 'password')

# Log into the user. If succeeded is True, result['auth'] will contain the authentication secret.
succeeded, result = twis.login('username', 'password')
if succeeded:
    auth_secret = result['auth']

# Post a tweet. 
succeeded, result = twis.post_tweet(auth_secret, 'A tweet')

# Get the general timeline. Note that we are passing an empty authentication secret and '-1' as the second 
# input parameter to get all the tweets in the general timeline. 
# If succeeded is True, result['tweets'] will contain a list of tweets.
succeeded, result = twis.get_timeline('', -1)

# Get the user timeline. Note that the second input parameter 100 specifies the maximum number of tweets 
# that will be included in the general timeline.
succeeded, result = twis.get_timeline(auth_secret, 100)

# Get the tweets posted by a user. Note that this user may be different from the currently logged-in user.
# If succeeded is True, result['tweets'] will contain a list of tweets.
succeeded, result = twis.get_user_tweets(auth_secret, 'username', -1)

# Follow a user.
succeeded, result = twis.follow(auth_secret, 'followee_username')

# Unfollow a user.
succeeded, result = twis.unfollow(auth_secret, 'followee_username')

# Get the follower list. If succeeded is True, result['follower_list'] will contain the follower list.
succeeded, result = twis.get_followers(auth_secret)

# Get the following list. If succeeded is True, result['following_list'] will contain the following list.
succeeded, result = twis.get_followings(auth_secret)

# Change the user password. If succeeded is True, result['auth'] will contain the new authentication secret.
succeeded, result = twis.change_password(auth_secret, 'password', 'new_password')

# Get the user profile. If succeeded is True, result['username'] will contain the username, result['password'] 
# will contain the password, and result['auth'] will contain the authentication secret.
succeeded, result = twis.get_user_profile(auth_secret)

# Log out of the user.
succeeded, result = twis.logout(auth_secret)

2. pytwis_clt

After you install the package, you will be able to launch pytwis_clt as a console command. To get the help information,

$ pytwis_clt -h
$ pytwis_clt --help

2.1. Connect to Redis

2.1.1. Connect to the local Redis server at the default port 6379 with no password.

$ ./pytwis_clt.py 

2.1.2. Connect to the local Redis server via the socket file /tmp/redis.sock with password zzzzzz.

Make sure that the unixsocket parameter is defined in your redis.conf file. It’s commented out by default.

$ ./pytwis_clt.py -s /tmp/redis.sock -a zzzzzz

2.1.3 Connect to a remote Redis server with IP = xxx.xxx.xxx.xxx at port yyyy with password zzzzzz.

$ ./pytwis_clt.py -h xxx.xxx.xxx.xxx -p yyyy -a zzzzzz

2.2. Available commands

After successfully connecting to the twitter clone, you can try the following commands in pytwis_clt.

2.2.1. register

Register a new user xxxxxx with password yyyyyy.

127.0.0.1:6379> register xxxxxx yyyyyy

2.2.2. login

Log into a user xxxxxxx with password yyyyyy.

127.0.0.1:6379> login xxxxxx yyyyyy

2.2.3. logout

Log out of the current user.

127.0.0.1:6379> logout

2.2.4. changepwd

Change the password. Assume that the old password is yyyyyy and the new password is zzzzzz.

127.0.0.1:6379> changepwd yyyyyy zzzzzz zzzzzz

2.2.5. userprofile

Get the profile of the currently logged-in user.

127.0.0.1:6379> userprofile

2.2.6. follow

Follow a user xxxxxx.

127.0.0.1:6379> follow xxxxxx

2.2.7. unfollow

Unfollow a user xxxxxx.

127.0.0.1:6379> unfollow xxxxxx

2.2.8. followers

Get the follower list of the current user.

127.0.0.1:6379> followers

2.2.9. followings

Get the following list of the current user.

127.0.0.1:6379> followings

2.2.10. post

Post a tweet.

127.0.0.1:6379> post <tweet>

2.2.11. timeline

Get the general/user timeline. It will return the user timeline if a user is logged in and will return the general timeline otherwise. Also, it will return all the tweets in the timeline if max-tweet-count is not specified.

127.0.0.1:6379> timeline [max-tweet-count]

2.2.12. tweetsby

Get the tweets posted by a user. It will return the tweets posted by the current logged-in user if no username is specified. Also, it will return all the tweets posted by the user if max-tweet-count is not specified.

127.0.0.1:6379> tweetsby [username] [max-tweet-count]

2.2.13. exit or quit

Exit the console program.

127.0.0.1:6379> exit
127.0.0.1:6379> quit

Note that some of the above commands have to be executed after a successful log-in.

  • logout
  • changepassword
  • userprofile
  • follow
  • unfollow
  • followers
  • followings
  • post
  • tweetsby

3. PEP8

We use pylint to enforce the Python Style Guide PEP8.

$ pylint pytwis
$ pylint tests

We have fixed all the convention violations, warnings, and errors in the packages pytwis and tests. We will address the refactor recommendations made by pylint later (see issue #8).

4. Unit test

Since this unit test requires a running local Redis server, it is in fact a small integration test. To run the test,

$ make test

5. Documentation

5.1. Sphinx

To generate the Sphinx HTML documentation,

$ make docs

5.2. README.rst

README.rst is generated from README.md via pandoc.

$ pandoc --from=markdown --to=rst --output=README.rst README.md