def address():
"""Get the address of a certain user.
From the users and servers tables, necessary details are extracted from
entries containing the given username.
Returns:
JSON response containing the address details of a certain user.
If the user is not found or the server is non existant, a failed JSON
response is returned.
"""
username = request.args.get('username')
# If username is not given, use the logged in username.
if username is None or username == '':
username = auth_username()
if username is None or username == '':
return bad_json_response("Bad request: Missing parameter 'username'.")
if users.exists(username=username):
server_id = users.export_one('server_id', username=username)
if not servers.exists(id=server_id):
bad_json_response('Server is not registered.')
name, address = servers.export_one('name', 'address', id=server_id)
return good_json_response({
'name': name,
'address': address,
'username': username
})
else:
return bad_json_response('User is not found.')
def edit():
"""Edit a certain users details in the central server.
The entry with the certain users username is edited in the users table in
the database.
Returns:
Success JSON response if the operation is successful.
Else a failed JSON response is returned with the correct error message.
"""
username = get_jwt_identity()
if users.exists(username=username):
if 'new_address' in request.form:
new_address = request.form['new_address']
if 'new_address' != '':
if servers.exists(address=new_address):
new_id = servers.export_one('id', address=new_address)
users.update({'server_id': new_id}, username=username)
return good_json_response({'new_address': new_address})
else:
return bad_json_response(
'This address does not exist in the database.')
else:
return bad_json_response('Address undefined.')
else:
return bad_json_response('Incorrect form.')
else:
return bad_json_response('No user found with the username ' +
username + '.')
def register():
"""Register a user to the central server.
For this registration, the username and server address are requested in the
form. A check is performed to see if the server is live. Then the user is
inserted into the users table.
Returns:
Success JSON response if the operation is successful.
If the username is valid or the server is not live, a failed JSON
response is returned.
"""
username = request.form['username']
address = request.form['server_address']
if not servers.exists(address=address):
return bad_json_response('Server is not registered.')
server_id = servers.export_one('id', address=address)
if ping(address):
if not users.exists(username=username):
users.insert(username=username, server_id=server_id)
else:
return bad_json_response(
'Username is already taken. Try again :).')
else:
return bad_json_response('This data server is not available. '
'Please contact the server owner.')
return good_json_response('success')
def get_pub_key(username):
"""Helper function to get the public key of a user.
Returns:
The public key of a user if available, else a bad JSON response.
"""
server_id = users.export_one('server_id', username=username)
if server_id is None:
return bad_json_response('No server_id')
pub = servers.export_one('pub_key', id=server_id)
if pub is None:
return bad_json_response('No pub')
return pub
def register():
"""Register a data server to the central server.
For this registration, the server name and address are requested in the
form. A check is performed to see if the server is live. Then the server
is inserted into the servers table if it does not already exists.
Returns:
JSON response containing the server id and the public key
at success, else a bad JSON response containing the error message.
"""
name = request.form['name']
address = request.form['address']
pub_key = ping(address)
if pub_key:
if not servers.exists(address=address):
result = servers.insert(
name=name, address=address, pub_key=pub_key)
return good_json_response({
'server_id': result,
'pub_key': pub_key
})
else:
name = servers.export_one('name', address=address)
return bad_json_response(
'The data server at "'
+ address
+ '" is already registered by the name "'
+ name
+ '".'
)
else:
return bad_json_response(
'The data server at "'
+ address +
'" did not respond. Is the installation correct?'
)