Why am I getting a 429 error with the Reddit API? - python-3.x

Question

I have been experimenting with flask and the Reddit api, but no matter what I try, I seem to be hitting the 429 'too many requests' error every time I try to receive the access token.
The initial user auth works without any issue, and I receive the code back and can validate that I've auth'd the app in my Reddit settings. I've also made sure to use a unique user-agent, as this seemed to resolve the issue for most people, and am not using any words like 'bot', 'curl', 'web' or anything else which would be a likely blocker.
As far as I'm aware, I am also well under the tolerance of getting rate limited with too many requests.
Given that this is the first time I'm using both flask, and the Reddit API, I'm sure I'm missing something obvious,but after 4 hours, copious Googling and reading all the docs, I don't understand what I'm getting wrong here.
import requests
import requests.auth
from flask import Flask, redirect, request, url_for
import string
import random
app = Flask(__name__)
client_id = "client id of my web app"
client_secret = "client secret of my web app"
base_auth_url = 'https://www.reddit.com/api/v1'
authorization_endpoint = '/authorize'
access_token_endpoint = '/access_token'
#app.route("/login")
def get_the_auth_code():
state = state_generator()
params = {
'client_id': client_id,
'response_type': 'code',
'state': state,
'redirect_uri': 'http://localhost:5000/redditor',
'scope': 'identity',
'user-agent': 'myapp v0.1 by /u/myredditusername'
}
return redirect(url_builder(authorization_endpoint, params))
#app.route("/redditor")
def get_the_access_token():
code = request.args.get('code')
client_auth = requests.auth.HTTPBasicAuth(client_id, client_secret)
post_data = {
'grant_type': 'authorization_code',
'code': code,
'redirect_uri': 'http://localhost:5000/redditor',
'user-agent': 'myapp v0.1 by /u/myredditusername'
}
response = requests.post(base_auth_url + access_token_endpoint, auth=client_auth, data=post_data)
token_json = response.json()
return token_json
def state_generator(size=25, chars=string.ascii_uppercase + string.digits):
return ''.join(random.choice(chars) for _ in range(size))
def url_builder(endpoint, parameters):
params = '&'.join(['%s=%s' % (k, v) for k, v in parameters.items()])
url = '%s%s?%s' % (base_auth_url, endpoint, params)
return url
if __name__ == "__main__":
app.run(debug=True)

Answer 1

With help from the Reddit community (specifically /u/nmtake), I found out where I was going wrong.
In my get_the_access_token() function, I was adding the user-agent field to my data parameters, instead of declaring it as part of the header.
Instead of:
post_data = {
'grant_type': 'authorization_code',
'code': code,
'redirect_uri': 'http://localhost:5000/redditor',
'user-agent': 'myapp v0.1 by /u/myredditusername'
}
response = requests.post(base_auth_url + access_token_endpoint, auth=client_auth, data=post_data)
I am now using the following, which works perfectly:
post_data = {
'grant_type': 'authorization_code',
'code': code,
'redirect_uri': 'http://localhost:5000/redditor',
}
post_headers = {
'user-agent': 'myapp v0.1 by /u/myredditusername'
}
response = requests.post(base_auth_url + access_token_endpoint, auth=client_auth, data=post_data, headers=post_headers)