Cloud Computing and Virtualization - Project Base App

This repo contains the demo web application that should be used as base in the final project (versions A + B). It consists of a web app (/app), and a websockets server (/ws). These run in a single Linux VM provisioned with Vagrant and shell scripts.

Pre-requisites

Install the latest versions of VirtualBox, VirtualBox Extension Pack and Vagrant:

• VirtualBox: https://www.virtualbox.org/wiki/Downloads
• VirtualBox Extension Pack: https://www.virtualbox.org/wiki/Downloads
• Vagrant: https://developer.hashicorp.com/vagrant/install

Note: After upgrading VirtualBox it is recommended to upgrade the guest additions as well.

Vagrant

The VM is defined in the Vagrantfile. Currently uses Ubuntu Server 22.04 and both services run on it. The provisioning is defined in the provision/web.sh script, which will:

• Install Apache2 HTTP Server
• Install PHP (and other libraries)
• Install PostgreSQL
  • Create a database and user
  • Import the provision/dump.sql script
• Run composer to install dependencies
• Setup the web app in apache2
• Update the DEPLOY_DATE in the .env file

You are free to change it as needed to achieve your desired configuration. If RAM/CPU is an issue, you might want to consider using a lighter distro, such as Alpine Linux, for some of your VMs (see generic/alpine38 or boxomatic/alpine-3.18, note that the package manager and other commands are different so you need to Google).

After provisioning, the web app should be accessible at http://192.168.44.10. In this base version, you must manually start the WebSockets server (see below).

Web App

The web app is a set of small php pages (security was not a concern) that ilustrate typical functionalities of a modern application, namely:

• Static / simple pages
• Sessions
• Database layer
• File uploads
• Data via WebSockets

Dependencies are installed via composer, and settings are defined in the .env file.

WebSockets Server

The websockets server is a simple one file server, which receives messages on port 8000 and broadcasts to all connected clients. Dependencies are also installed via composer. It uses Ratchet as the websockets server, and should be started in the CLI with:

vagrant ssh
cd /vagrant/ws
php websockets_server.php
# you may want to configure it as a daemon / service to autostart by default

Load Testing

If you want to load test the web app, you can download tools such as hey, or vegeta, and run sets of requests against specific endpoints.

Example under Win10, using Git BASH:

# create a folder to dl the tools (outside of the project)
mkdir HTTPLoad
cd HTTPLoad

# download hey and vegeta
curl -o hey.exe https://hey-release.s3.us-east-2.amazonaws.com/hey_windows_amd64
curl -LJO https://github.com/tsenart/vegeta/releases/download/v12.8.3/vegeta-12.8.3-windows-amd64.zip
unzip vegeta-12.8.3-windows-amd64.zip
rm vegeta-12.8.3-windows-amd64.zip

# check help (under other cli you might use hey.exe...)
./hey -h
./vegeta -h

# run hey with default settings
./hey http://192.168.44.10/db.php

Summary:
  Total:        5.4095 secs
  Slowest:      4.9218 secs
  Fastest:      0.1381 secs
  Average:      0.7955 secs
  Requests/sec: 36.9719

Response time histogram:
  0.138 [1]     |
  0.616 [119]   |■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■
  1.095 [50]    |■■■■■■■■■■■■■■■■■
  1.573 [11]    |■■■■
  2.052 [2]     |■
  2.530 [0]     |
  3.008 [6]     |■■
  3.487 [0]     |
  3.965 [1]     |
  4.443 [7]     |■■
  4.922 [3]     |■

Latency distribution:
  10% in 0.1739 secs
  25% in 0.2481 secs
  50% in 0.5157 secs
  75% in 0.7591 secs
  90% in 1.3820 secs
  95% in 3.9908 secs
  99% in 4.9216 secs

Details (average, fastest, slowest):
  DNS+dialup:   0.0006 secs, 0.1381 secs, 4.9218 secs
  DNS-lookup:   0.0000 secs, 0.0000 secs, 0.0000 secs
  req write:    0.0000 secs, 0.0000 secs, 0.0004 secs
  resp wait:    0.7947 secs, 0.1378 secs, 4.9170 secs
  resp read:    0.0002 secs, 0.0001 secs, 0.0011 secs

Status code distribution:
  [200] 200 responses

# Run vegeta test (from vegeta -h)
 echo "GET http://192.168.44.10/db.php" | ./vegeta attack -duration=5s | tee results.bin | ./vegeta report
Requests      [total, rate, throughput]         250, 50.19, 44.65
Duration      [total, attack, wait]             5.599s, 4.981s, 618.628ms
Latencies     [min, mean, 50, 90, 95, 99, max]  125.287ms, 444.677ms, 213.447ms, 1.186s, 2.453s, 3.427s, 3.466s
Bytes In      [total, mean]                     1039250, 4157.00
Bytes Out     [total, mean]                     0, 0.00
Success       [ratio]                           100.00%
Status Codes  [code:count]                      200:250
Error Set:

# Generate vegeta report based on previous test
./vegeta report -type=json results.bin > metrics.json

# Plot results as latency vs time elapsed (to plot.html)
cat results.bin | ./vegeta plot > plot.html

# Show histogram (terminal)
cat results.bin | ./vegeta report -type="hist[0,100ms,200ms,300ms]"
Bucket           #    %       Histogram
[0s,     100ms]  0    0.00%
[100ms,  200ms]  103  41.20%  ##############################
[200ms,  300ms]  80   32.00%  ########################
[300ms,  +Inf]   67   26.80%  ####################