Building Small Web Tools on Tencent Cloud: Questionnaire System, QR‑Code Utility, Map Search, and Xcode Download

This article documents a series of lightweight web tools that the author built while learning and practicing cloud development on Tencent Cloud. The tools include a questionnaire system, a QR‑code generator/scanner, a map‑search utility, and a script for retrieving Xcode dmg/docset download URLs.

Environment Setup (PHP)

The author uses a $65/month Ubuntu 14.04 x64 instance on Tencent Cloud. Both Apache+PHP+MySQL and Nginx+PHP‑FPM are described. Example commands for installing Apache:

sudo apt-get update
sudo apt-get install apache2 php5
service apache2 start

Preferred Nginx+PHP setup commands (including adding the official Nginx repository, installing, and configuring the service):

# Add Nginx official key
wget http://nginx.org/keys/nginx_signing.key
sudo apt-key add nginx_signing.key
rm nginx_signing.key
# Add Nginx repository
codename=$(lsb_release -a|grep Codename|awk '{print $2}')
echo deb http://nginx.org/packages/ubuntu/ $codename nginx > nginx.list
echo deb-src http://nginx.org/packages/ubuntu/ $codename nginx >> nginx.list
sudo cp nginx.list /etc/apt/sources.list.d/nginx.list
# Install Nginx
sudo apt-get update
sudo apt-get install nginx
# Verify port 80
netstat -tln
# Add nginx user to www-data group
sudo usermod -a -G www-data -G nginx nginx

Sample nginx virtual‑host configuration:

server {
listen       80;
server_name  localhost;
root /home/ubuntu/www;
index   index.php index.html index.htm;
error_page   500 502 503 504  /50x.html;
location = /50x.html {
root /home/ubuntu/www;
}
location ~ \.php$ {
try_files      $uri = 404;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass   unix:/var/run/php5-fpm.sock;
fastcgi_index  index.php;
include         fastcgi_params;
fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
}
}

Enable short open tags and restart services:

sed -i 's/short_open_tag = Off/short_open_tag = On/g' /etc/php5/fpm/php.ini
sudo service php5-fpm restart
sudo service nginx restart

Create a demo page to verify PHP:

echo "
" > /home/ubuntu/www/index.php

Questionnaire System

Background: The author needed a self‑hosted alternative to Google Forms. The system stores form definitions as JSON, saves responses to CSV files, and provides export functionality.

Implementation steps (high‑level):

Front‑end: JavaScript builds form elements; each element has an EntryType (text, single‑choice, etc.) and a Choices array.

Back‑end: PHP receives the whole JSON payload, stores it with a random ID, and later renders the form based on the stored JSON.

Submission: Answers are posted as key‑value pairs, reordered, and saved as CSV.

Export: A special link returns the CSV for download.

Sample JSON for a single question:

{
"EntryId": 3,
"Composite": false,
"QuestionTitle": "无标题的问题",
"HelpText": "",
"EntryType": 4,
"Choices": [
{"SelectedByDefault": false, "Value": "选项 1", "Label": "", "GoToPage": -2},
{"SelectedByDefault": false, "Value": "选项 2", "Label": "", "GoToPage": -2}
],
"OtherOptionEnabled": false,
"Required": false,
"GoToPageEnabled": false,
"Position": 3
}

QR‑Code Tool

Background: The author wanted a lightweight QR‑code generator without third‑party tracking and a way to generate short URLs for sharing.

Generation (pure JavaScript):

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script>
<script src="http://jeromeetienne.github.io/jquery-qrcode/src/jquery.qrcode.js"></script>
<div id="qrcode"></div>
$('#qrcode').qrcode({ width: 64, height: 64, text: 'hello, world' });

To obtain a downloadable <img> instead of a canvas:

<img id="qr_img"/>
function make_qrcode(text, width) {
width = width || 256;
var div = $('
');
div.qrcode({ width: width, height: width, text: text });
var url = div.find('canvas')[0].toDataURL();
$('#qr_img').attr('src', url);
}
make_qrcode('hello, world', 256);

Parsing (jsqrcode library):

var reader = new FileReader();
reader.onload = function(e) { qrcode.decode(e.target.result); };
reader.readAsDataURL(file);

Short‑URL generation is handled by a simple PHP script that calls api.t.sina.com.cn .

Map Search Utility

Background: Quickly locate company shuttle stops on a map.

Implementation uses Baidu Map API to geocode a city name and display markers. Key JavaScript snippet:

var city = '深圳';
var geocoder = new BMap.Geocoder();
var map = new BMap.Map('container');
geocoder.getPoint(city, function(point){
console.info('point:', point);
map.centerAndZoom(point, 11);
map.addControl(new BMap.MapTypeControl());
map.addControl(new BMap.NavigationControl());
map.addControl(new BMap.ScaleControl({anchor: BMAP_ANCHOR_TOP_LEFT}));
});

Xcode dmg / docset Download URL Retrieval

Background: Direct download of Xcode dmg and documentation packages is faster than using the App Store, but third‑party sources pose security risks.

Implementation (PHP + CFPropertyList):

$url = 'https://developer.apple.com/library/downloads/docset-index.dvtdownloadableindex';
$xml = file_get_contents($url);
$plist = new CFPropertyList\CFPropertyList();
$plist->parse($xml);
$docs = $plist->toArray();

The script parses Apple’s CFPropertyList file and outputs a friendly list of download URLs.

Overall, the article serves as a practical guide for setting up a low‑cost cloud environment, deploying PHP/NGINX services, and building small, reusable web utilities.