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pythonalexa-skills-kitngrok

Alexa Skill Development using flask-ask and ngrok error

I'm trying to begin developing a skill for Alexa using flask-ask and ngrok in python. Following is my code:

from flask import Flask

from flask_ask import Ask, statement


app = Flask(__name__)
ask = Ask(app, "/")

@ask.launch
def start_skill():
    welcome_message = 'Hello there'
    return statement(welcome_message)

@ask.intent("sampleIntent")
def sampleIntent():
    return statement('I am the sample intent')
    
@app.route('/')
def homepage():
    return "Hi,there"


if __name__ == '__main__':

    app.run(port=7025, debug=True)

The code runs fine on my machine and returns the correct output if I print it out and I am able to view the text "Hi,there" when i view both the ngrok https link and the python localhost link. Both ngrok and the python code are on the same port of 7025.

I know the issue is cryptography as i have version 3.0 installed. I was instructed by the tutorial to downgrade both cryptography and Werkzeug. I was able to downgrade Werkzeug but was not able to downgrade cryptography. The pip freeze is bellow:

aniso8601==1.2.0
appdirs==1.4.4
ask-sdk-core==1.14.0
ask-sdk-model==1.24.0
ask-sdk-runtime==1.14.0
ask-sdk-webservice-support==1.2.0
asn1crypto==1.4.0
certifi==2020.6.20
cffi==1.14.1
chardet==3.0.4
click==7.1.2
cryptography==3.0
distlib==0.3.1
filelock==3.0.12
Flask==0.12.1
Flask-Ask==0.9.8
flask-ask-sdk==1.0.0
idna==2.10
itsdangerous==1.1.0
Jinja2==2.11.2
MarkupSafe==1.1.1
openssl-python==0.1.1
pycparser==2.20
pyOpenSSL==17.0.0
pyserial==2.7
python-dateutil==2.8.1
PyYAML==3.12
requests==2.24.0
six==1.11.0
Unidecode==1.1.1
urllib3==1.25.10
virtualenv==20.0.30
Werkzeug==0.16.0

When I try and downgrade cryptography to the version 2.1.4, I get a lot of red text, however, the first line seems to be:

   Running setup.py install for cryptography ... error

I am running python version 3.8.5 and I have pip version 20.2.2.

Solution

  • There are several ways to solve this, to my mind the easiest looks like this (git required):

    1. navigate to your project's root folder
    2. clone the flask-ask repo: git clone https://github.com/johnwheeler/flask-ask -- this will create a local copy of the repo in your project's directory
    3. modify the requirements.txt file in /your_project/flask_ask/ and remove the version number from cryptography's package. It's currently frozen at ==2.1.4 -- simply remove ==2.1.4 to allow pip to resolve the correct dependency.
    4. Once you've modified the underlying package, and still in /your_project/flask_ask/ run pip install -e . -- this will install an "editable" copy of the flask_ask package so that further updates will be recognized

    enter image description here