79 lines
3 KiB
Python
Executable file
79 lines
3 KiB
Python
Executable file
#!/usr/bin/env python3
|
|
from flask import Flask, render_template, url_for, request, redirect, abort
|
|
import sqlite3, random, string, time, hashlib, base64
|
|
from urllib.parse import urlparse
|
|
|
|
app = Flask(__name__)
|
|
|
|
@app.route('/', methods=['GET', 'POST'])
|
|
@app.route('/<shortLink>', methods=['GET', 'POST'])
|
|
def short(shortLink=""):
|
|
if request.method == "GET":
|
|
if shortLink:
|
|
conn = sqlite3.connect("data/links.sqlite")
|
|
c = conn.cursor()
|
|
result = c.execute('SELECT * FROM links WHERE shortLink=?', (shortLink, )).fetchone()
|
|
conn.close()
|
|
if result:
|
|
url = result[1]
|
|
parsedUrl = urlparse(url)
|
|
if parsedUrl.scheme == "":
|
|
url = "http://" + url
|
|
return redirect(url, code=301) # Redirect to long URL saved in the database
|
|
else:
|
|
return render_template("index.html", name=shortLink, message="Enter long URL for "+ request.url_root + shortLink+":", message_type="info") # Custom link page
|
|
else:
|
|
return render_template("index.html", name=shortLink) # Landing page
|
|
elif request.method == "POST": # Someone submitted a new link to short
|
|
wishId = request.form["wishId"]
|
|
longUrl = request.form["url"]
|
|
if wishId:
|
|
databaseId = insertIdUnique(wishId, longUrl)
|
|
else:
|
|
databaseId = insertIdUnique("", longUrl)
|
|
return request.url_root + databaseId # Short link in plain text
|
|
|
|
def insertIdUnique(idToCheck, longUrl):
|
|
hashUrl = hashlib.sha256(longUrl.encode()).digest()
|
|
base64Url = base64.urlsafe_b64encode(hashUrl).decode()
|
|
if len(idToCheck) == 0:
|
|
idToCheck = base64Url[:4]
|
|
|
|
conn = sqlite3.connect("data/links.sqlite")
|
|
c = conn.cursor()
|
|
try:
|
|
c.execute('INSERT INTO links VALUES (?, ?, ?, ?, ?)', (idToCheck, longUrl, int(time.time()), request.remote_addr, "default" ))
|
|
databaseId = idToCheck
|
|
conn.commit()
|
|
conn.close()
|
|
except sqlite3.IntegrityError as e:
|
|
print("Hash already exists, does the long URL matches?")
|
|
longUrlDb = c.execute('SELECT * FROM links WHERE shortLink=?', (idToCheck, )).fetchone()
|
|
if longUrl == longUrlDb[1]:
|
|
print(longUrl + " is already in database with id " + idToCheck + ". Serving old id…")
|
|
databaseId = idToCheck
|
|
else:
|
|
print("Found real hash collision for " + longUrl + " and " + longUrlDb[1])
|
|
conn.commit()
|
|
conn.close()
|
|
if len(base64Url) - 1 >= len(idToCheck) + 1:
|
|
databaseId = insertIdUnique(base64Url[:len(idToCheck)+1], longUrl)
|
|
else:
|
|
print("Can't produce a long enough hash from the new link to be unique. This should never happen")
|
|
print("Bailing out, you are on your own. Good luck.")
|
|
print("=========================================================================================")
|
|
abort(500)
|
|
|
|
return databaseId
|
|
|
|
def initDB():
|
|
conn = sqlite3.connect("data/links.sqlite")
|
|
c = conn.cursor()
|
|
c.execute('''CREATE TABLE IF NOT EXISTS links (shortLink UNIQUE NOT NULL, longLink, timestamp, ip, redirectMethod);''')
|
|
conn.commit()
|
|
conn.close()
|
|
|
|
if __name__ == '__main__':
|
|
initDB()
|
|
app.run(debug=True) # If you call this file directly it will always run in debug mode. THIS IS VERY DANGEROUS!
|