MP2: Tiny Social Network Service

CSCE 438 - Distributed Systems Machine Problem 2
MP2: Tiny Social Network Service
150 points
Due: March 6th, 2023, at 11:59pm
1 Overview
The objective of this assignment is to exercise your knowledge about Google
Protocol Buffers and gRPC by building a Tiny SNS, similar in concept with
posting and receiving status updates on Facebook or Twitter. In this service,
the following must be considered:
1. Each user(client) has his/her own “Timeline” The user is allowed to
post to his/her own timeline. That is, whenever new user appears, the
server needs to create new timeline for the new user.
2. A user is allowed to FOLLOW any other user (i.e., is allowed to post
updates to other users’ timeline), after submitting the FOLLOW command. For example, when an user posts an update to his/her timeline,
followers can see it on his/her timeline.
3. All timeline must be persistent, i.e., their contents must be stored in
files in the local file system. The files must not be encrypted, for now.
4. A user operates in two modes: “command mode” and “timeline mode”.
When the client program starts, it automatically starts in command
mode. The commands the client can send are: FOLLOW, UNFOLLOW, LIST, TIMELINE
5. The LIST command retrieves from the server the list of existing users
and the list of users who follow the current user.
6. The TIMELINE command switches a user from command mode to
timeline mode and allows the user to post some updates to both his/her
and followers’ timeline.
7. Once a user issues the TIMELINE command, it can not return to the
command mode, and it will stay only in TIMELINE mode.
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CSCE 438 - Distributed Systems Machine Problem 2
8. The “UNFOLLOW <username>” command removes the current user
from the given user’s timeline.
9. The “FOLLOW <username>” command adds the current user to the
given user’s timeline.
10. After submitting the FOLLOW command, the user sees only new
posts. That is, the user can not see any posts that were posted before
the user started to follow.
11. After submitting the TIMELINE command, the user sees the last 20
posts as follows: “username”, “posting time” and “actual posting.”
12. All communications will be using Google Protocol Buffers v3 and
gRPC.
13. The client and server must be started in the following ways:
$ ./tsd <port_number>
$ ./tsc <host_name> <port_number> <username>
2 What to Hand In
The running system will consist of the tiny SNS server (tsd) (and possibly
other servers) and the tiny SNS client (tsc). As platform, you should use
the provided virtual machine where Google Protocol Buffers v3 and gRPC
are installed, and develop the program in C++. (See the document “Programming Guide HW2”)
2.1 Design
Before you start hacking away, write a design document. The result should
be a system level design document, which you hand in along with the source
code. Do not get carried away with it, but make sure it convinces the reader
that you know how to attack the problem. List and describe the components
of the system: Client/Server Program, and their interaction.
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CSCE 438 - Distributed Systems Machine Problem 2
For this assignment, we will not stress test your code. As long as the code
executes correctly for up to 10 clients, one client at a time updating, you
will receive full credit.
2.2 Source code
Hand in the source code, comprising of a makefile, a file tsd.cc, a file tsc.c
and any auxiliary files (for example Google protocol buffers and gRPC files).
The code should be easy to read (read: well-commented!). The instructors
reserve the right to deduct points for code that they considers undecipherable.
2.3 Grading criteria
The 150pts for this assignment are given as follows: 15pts for complete
design document, 15pts for compilation, 120pts for 6 test cases (the test
cases have different weights). Refer to provided 6 cases tests which cover
most scenarios but these are slightly different with the test cases for grading.
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