csci499_chengtsu

An FaaS platform and a social network system on top of it. For USC CSCI499 - Robust Systems Design and Implementation.

Table of Contents

• Architecture
• Pre-reqs
• Build
• Usage
• Test
• Authors
• Acknowledgments

Architecture

As shown in the diagram, there will be four executables built in this project (except tests), they are:

• caw_cli: The Caw command-line tool who accepts the user's input, sends requests to the Faz Server through the CawClient accordingly, and displays response messages to the user based on the return from the Faz Server.

• caw_cli_go: Same as caw_cli except caw_cli is built from C++ sources and caw_cli_go is built from Go sources.

• faz_server: The Faz Server who hosts a FazService, which executes the corresponding Caw handler functions based on the incoming event types, and sends back response messages. During the execution of Caw handler functions, interactions with a KVStore Server may occur, through a KVStoreClient.

• kvstore_server: The KVStore Server who hosts a KVStoreService, which performs put/get/remove operations to the underlying KVStore instance as requested, and sends back response messages to remote callers.

Pre-reqs

If you are using vagrant, the Vagrantfile at the project root directory can install all dependencies for you automatically. Assume you have cloned the project on your host machine and are already in the project root directory, you just need to to create your guest machine and connect to it.

vagrant up
vagrant ssh
cd csci499_chengtsu

If not using vagrant, to build and run this project locally you will need a few things:

• Install googletest
• Install gflags
• Install glog
• Install gRPC and Protobuf
• Install Go
• Install Go plugins for the protocol compiler

Build

Assume you are already in the project root directory (on your vagrant guest, or on your host machine after all pre-requisites installed), run:

mkdir build && cd build
cmake ..
make

If you are using vagrant and the provisioning script in Vagrantfile somehow does not work perfectly and causes errors when you are building or running the project (I have tested for several times to make it work well on my own machine, but I am not completely sure that works perfectly for you), you may need to manually fix the errors accordingly.

Usage

To get the Caw platform work, you need to first start the KVStore server, and then start the FaaS server. Then you can use the Caw command-line tool to use the Caw functionalities.

Assume you are already in a directory containing the built executables. Below are instructions to get the system work.

KVStore Server

To run the KVStore server. When given the --store <file> flag, the key-value store server will store all operations to the given file; if the file already exists when it starts, it will first load entries from the specified previously-stored file and then store any new operations to that same file. If no flag is given, it will not store data to any file.

./kvstore_server [--store <file>]

FaaS Server

To run the FaaS server

./faz_server

Caw Command-line Tool

To use the Caw command-line tool for different purposes.

• To hook all Caw functions:
  • ./caw_cli --hook_all
  • ./caw_cli_go --hook_all
• To register a user:
  • ./caw_cli --registeruser <username>
  • ./caw_cli_go --registeruser <username>
• To follow another user on behalf of a user:
  • ./caw_cli --user <username> --follow <to_follow>
  • ./caw_cli_go --user <username> --follow <to_follow>
• To get a user's profile:
  • ./caw_cli --user <username> --profile
  • ./caw_cli_go --user <username> --profile
• To post a caw on behalf of a user:
  • ./caw_cli --user <username> --caw <text>
  • ./caw_cli_go --user <username> --caw <text>
• To post a caw replying an existing caw on behalf of a user:
  • ./caw_cli --user <username> --caw <text> --reply <parent_caw_id>
  • ./caw_cli_go --user <username> --caw <text> --reply <parent_caw_id>
• To read a caw thread starting from a caw:
  • ./caw_cli --read <caw_id>
  • ./caw_cli_go --read <caw_id>
• To unhook all Caw functions:
  • ./caw_cli --unhook_all
  • ./caw_cli_go --unhook_all

For Example:

# C++ version
./caw_cli --hook_all
./caw_cli --registeruser Eren
./caw_cli --registeruser Mikasa
./caw_cli --user Mikasa --follow Eren
./caw_cli --user Mikasa --profile
./caw_cli --user Eren --caw "Sit down, Reiner"
./caw_cli --unhook_all
# Go version
./caw_cli_go --hook_all
./caw_cli_go --registeruser Eren
./caw_cli_go --registeruser Mikasa
./caw_cli_go --user Mikasa --follow Eren
./caw_cli_go --user Mikasa --profile
./caw_cli_go --user Eren --caw "Sit down, Reiner"
./caw_cli_go --unhook_all

Note! The command-line tool also supports chaining flags to enable you to run multiple functions in one command for convenience. For example you can do some thing like

./caw_cli --hook_all --registeruser Reiner --user Reiner --follow Zeke \ 
  --caw "I am the Armored Titan, he is the Colossal Titan" \
  --profile --unhook_all

When flags for multiple functions are specified, the requested functions will always be executed in the order of: HookAll (first), RegisterUser, Follow, Profile, Caw, Read, UnhookAll (last).

Also note that the C++ and Go command-line tool share the same hooking, that means: if you hooked all functions in one command-line tool, you don't need to hook them again with the other one to get it work; same for unhooking.

Test

Assume you are already in a directory containing the built executables. Below are instructions to run the tests.

To run the KVStore (storage only) test

./kvstore_test

To run the Caw handler function test

./caw_handler_test

To run the KVStore shell to do interactive testing. It will prompt usage after you run the below command, just follow the usage message. Note that you can even run this when the other executables are running to inspect the content of the KVStore, or even update the content to create some extreme cases (for example, a posted caw accidentally lost in the database).

./kvstore_shell_test

Authors

• Cheng-Tsung Liu
• Guosheng Zhou ("phase3" branch)

Acknowledgements

(In alphabetical order of first name)

• Adam Egyed
• Barath Raghavan
• Grace Susanto