We Keep Coding

How to use Flask development server successfully with Ajax post request?

I'm currently using Flasks's development server instead of using a separate one because I don't need the extra bulk. My server will not be processing many requests at once, so I feel the development server is fine enough.
What I'm Trying To Do
I have a python script that I'm trying to run with the click of a button on a web page. This web page is run on an Apache 2 web server on Ubuntu.
What I've Done
I've installed Flask and tried to post to my python script, but I always get this error:
* Serving Flask app "ResetPOE" (lazy loading)
* Environment: production WARNING: Do not use the development server in a production environment. Use a production WSGI server instead. * Debug mode: on
It always returns to my error block in my Ajax request and never to my success block. I do not get any return JSON from my Python script. I just want to know whether or not my script ran, I don't necessarily need any output from the script itself.
P.S. my Python may be incorrect, but I haven't even gotten it to recognize it yet, so that's been on the back burner for now. I'm just trying to get the post request to be successful.
ajax.js
function ajaxCall(input) {
var data = {"param" : input};
$.ajax({
url: "/cgi-bin/reset.py/request",
type: "POST",
contentType: "application/json",
data: JSON.stringify(data),
dataType: 'json',
success: function(response){
console.log("success");
console.log(response);
},
error: function(xhr, status, error) {
console.log("error");
var err = xhr.responseText;
console.log(err);
}
});
}
reset.py
#!/usr/bin/python3
print("Content-type: text/html")
print ("")
from flask import Flask, request, jsonify
import json
app = Flask(__name__)
#app.route('/')
def sendOK(environ, start_response):
status = '200 OK'
output = "Hello World!"
response_headers = [('Content-type', 'text/plain'),('Content-Length', str(len(output)))]
start_response(status, response_headers)
return [output]
#app.route('/request', methods=['POST'])
def processRequest():
data = request.form["param"]
# other code to do stuff with the data...
return Response(json.dumps({"status":"success"}), mimetype="application/json")
if __name__=="__main__":
app.run(debug=True, threaded=True, host="192.168.1.101")
It returns a 200 (OK) in my browser, but I'm not getting any return values, and I can tell my error block is executing and not my success block.

Python flask server issue

Could you please help me with Python-Flask server misunderstanding. I have some project with flask, it perfectly works on local server 127.0.0.1, but when I moved it to the Web Server (blue host), some of my script give me these errors:
Here I have jQuery, Ajax response to show a table without reloading page:
<button class="myButton" id = "Lbutton">Load</button>
<script>
$("#Lbutton").click(function(){
$.ajax({
url: "/table,
type: "get",
data: {jsdata: $( "#select option:selected" ).text()},
success: function(response) {
$("#place_for_suggestions").html(response);
},
error: function(xhr) {
// handle error
}
});
});
</script>
url: "/table, is the link for Flask function:
#FlaskApp2.route('/table')
def table():
modid = request.args.get('jsdata')
return render_template('table.html')
But finally the Server gave me error:
File does not exist: /home1/user/public_html/table
Why direct link for action, server understand like a link for a file?
So, every action to Python-Flask
<form action="/sendemail" method="post">
the Server understand like a link and give an error message !
What I'm doing wrong ?

Solved, I need to put the full path in action and route() decorator #app.route "/.../templates/table.html"

Most likely you need to add the POST method to your route definition.
#FlaskApp2.route('/table')
becomes:
#FlaskApp2.route('/table', methods=['GET', 'POST'])
Check out the documentation here:
http://flask.pocoo.org/docs/0.12/quickstart/#http-methods
Which has an example of an endpoint that accepts both GET and POST HTTP methods.
Also check out a related question: Flask example with POST

Facebook Messenger with Flask

I'm trying to get the FB messenger API working using Python's Flask, adapting the following instructions: https://developers.facebook.com/docs/messenger-platform/quickstart
So far, things have been going pretty well. I have verified my callback and am able to receive the messages I send using Messenger on my page, as in the logs in my heroku server indicate the appropriate packets of data are being received by my server. Right now I'm struggling a bit to send responses to the client messenging my app. In particular, I am not sure how to perform the following segment from the tutorial in Flask:
var token = "<page_access_token>";
function sendTextMessage(sender, text) {
messageData = {
text:text
}
request({
url: 'https://graph.facebook.com/v2.6/me/messages',
qs: {access_token:token},
method: 'POST',
json: {
recipient: {id:sender},
message: messageData,
}
}, function(error, response, body) {
if (error) {
console.log('Error sending message: ', error);
} else if (response.body.error) {
console.log('Error: ', response.body.error);
}
});
}
So far, I have this bit in my server-side Flask module:
#app.route('/', methods=["GET", "POST"])
def chatbot_response():
data = json.loads(req_data)
sender_id = data["entry"][0]["messaging"][0]["sender"]["id"]
url = "https://graph.facebook.com/v2.6/me/messages"
qs_value = {"access_token": TOKEN_OMITTED}
json_response = {"recipient": {"id": sender_id}, "message": "this is a test response message"}
response = ("my response text", 200, {"url": url, "qs": qs_value, "method": "POST", "json": json_response})
return response
However, running this, I find that while I can process what someone send my Page, it does not send a response back (i.e. nothing shows up in the messenger chat box). I'm new to Flask so any help would be greatly appreciated in doing the equivalent of the Javascript bit above in Flask.
Thanks!

This is the code that works for me:
data = json.loads(request.data)['entry'][0]['messaging']
for m in data:
resp_id = m['sender']['id']
resp_mess = {
'recipient': {
'id': resp_id,
},
'message': {
'text': m['message']['text'],
}
}
fb_response = requests.post(FB_MESSAGES_ENDPOINT,
params={"access_token": FB_TOKEN},
data=json.dumps(resp_mess),
headers = {'content-type': 'application/json'})
key differences:
message needs a text key for the actual response message, and you need to add the application/json content-type header.
Without the content-type header you get the The parameter recipient is required error response, and without the text key under message you get the param message must be non-empty error response.

This is the Flask example using fbmq library that works for me:
echo example :
from flask import Flask, request
from fbmq import Page
page = fbmq.Page(PAGE_ACCESS_TOKEN)
#app.route('/webhook', methods=['POST'])
def webhook():
page.handle_webhook(request.get_data(as_text=True))
return "ok"
#page.handle_message
def message_handler(event):
page.send(event.sender_id, event.message_text)

In that scenario in your tutorial, the node.js application is sending an HTTP POST request back to Facebook's servers, which then forwards the content on to the client.
So far, sounds like your Flask app is only receiving (AKA serving) HTTP requests. The reason is that that's what the Flask library is all about, and it's the only thing that Flask does.
To send an HTTP request back to Facebook, you can use any Python HTTP client library you like. There is one called urllib in the standard library, but it's a bit clunky to use... try the Requests library.
Since your request handler is delegating to an outgoing HTTP call, you need to look at the response to this sub-request also, to make sure everything went as planned.
Your handler may end up looking something like
import json
import os
from flask import app, request
# confusingly similar name, keep these straight in your head
import requests
FB_MESSAGES_ENDPOINT = "https://graph.facebook.com/v2.6/me/messages"
# good practice: don't keep secrets in files, one day you'll accidentally
# commit it and push it to github and then you'll be sad. in bash:
# $ export FB_ACCESS_TOKEN=my-secret-fb-token
FB_TOKEN = os.environ['FB_ACCESS_TOKEN']
#app.route('/', method="POST")
def chatbot_response():
data = request.json() # flasks's request object
sender_id = data["entry"][0]["messaging"][0]["sender"]["id"]
send_back_to_fb = {
"recipient": {
"id": sender_id,
},
"message": "this is a test response message"
}
# the big change: use another library to send an HTTP request back to FB
fb_response = requests.post(FB_MESSAGES_ENDPOINT,
params={"access_token": FB_TOKEN},
data=json.dumps(send_back_to_fb))
# handle the response to the subrequest you made
if not fb_response.ok:
# log some useful info for yourself, for debugging
print 'jeepers. %s: %s' % (fb_response.status_code, fb_response.text)
# always return 200 to Facebook's original POST request so they know you
# handled their request
return "OK", 200

When doing responses in Flask, you have to be careful. Simply doing a return statement won't return anything to the requester.
In your case, you might want to look at jsonify(). It will take a Python dictionary and return it to your browser as a JSON object.
from flask import jsonify
return jsonify({"url": url, "qs": qs_value, "method": "POST", "json": json_response})
If you want more control over the responses, like setting codes, take a look at make_response()

AngularJS - http request with Basic Auth (connect to FreeNAS)

Im trying to connect to the REST API of FreeNAS (http://api.freenas.org/authentication.html) within my AngularJS app. The API uses basic authentication with username and password.
In python this is a very easy thing as there is only one line of code:
requests.get('http://freenas.mydomain/api/v1.0/account/bsdusers/',auth=('root', 'freenas'))
I tried to find something for AngularJS but stumbled only over excrutiating code, e.g. How do I get basic auth working in angularjs?
Is there anything available like this:
$http({
method: 'GET',
url: 'http://freenas.mydomain/api/v1.0/account/bsdusers/',
auth: ['username':'root', 'password':'pw']
}).then(function successCallback(response) {
// this callback will be called asynchronously
// when the response is available
}, function errorCallback(response) {
// called asynchronously if an error occurs
// or server returns response with an error status.
});

You need to create a function for encoding the user and password in Base64("username:password") and add Authorization header.
You can try encoding your username and password over here https://www.base64encode.org/ and see if it works. "root:freenas" being cm9vdDpmcmVlbmFz you can try the code below.
$http.defaults.headers.common['Authorization'] = 'Basic cm9vdDpmcmVlbmFz';
Once you get it working get implement the Base64 factory you posted ( How do I get basic auth working in angularjs? )
Hope it helps :)

You can try like this.
$http.defaults.headers.common = {"Access-Control-Request-Headers": "accept, origin, authorization"};
$http.defaults.headers.common['Authorization'] = 'Basic ' + Base64.encode('root' + ':' + 'freenas');
$http({
method: 'GET',
url: 'http://freenas.mydomain/api/v1.0/account/bsdusers/'
}).then(function successCallback(response) {
// this callback will be called asynchronously
// when the response is available
}, function errorCallback(response) {
// called asynchronously if an error occurs
// or server returns response with an error status.
});

Implement Google+ Sign-In without Flask (on GAE)

I've got an app on Google App Engine for which I use the webapp2 authentication as described in this tutorial (thus Google Account API is not being used for user account management).
Therefore I'm using this Google tutorial to implement Google+ Sign-In. The front-end works fine, however I am having troubles with the callback. I would like to do this without Flask, since the only thing it seems to be used for is generating a response. The original code for the first part of the callback is:
if request.args.get('state', '') != session['state']:
response = make_response(json.dumps('Invalid state parameter.'), 401)
response.headers['Content-Type'] = 'application/json'
return response
To get rid of the Flask dependency, I rewrote this to:
if self.request.get('state') != self.session.get('state'):
msg = json.dumps('Invalid state parameter.')
self.response.headers["Content-Type"] = 'application/json'
self.response.set_status(401)
return self.response.out.write(msg)
The problem though, is that self.request.get('state') returns nothing. I'm guessing this is because I am not reading the response properly, however I don't know how to do it right.
The Javascript that launches the callback is:
function signInCallback(authResult) {
if (authResult['code']) {
// Send the code to the server
$.ajax({
type: 'POST',
url: '/signup/gauth',
contentType: 'application/octet-stream; charset=utf-8',
success: function(result) {
console.log(result),
processData: false,
data: authResult['code']
});
} else if (authResult['error']) {
// There was an error.
// Possible error codes:
// "access_denied" - User denied access to your app
// "immediate_failed" - Could not automatially log in the user
console.log('There was an error: ' + authResult['error']);
}
}