How can I add a signature in my Google static map API - google-maps

Question

I want to get some maps from Google statics map, but there are many requests in my code at least 60000 times. Google can allow users to get request 25000 times per day. If I want to get more requests, I must make a signature on my code.
def download_image(lat, lon, filename):
param_url = "maptype=satellite&center="+ lat + "," + lon + "&zoom=16&size=400x400&style=feature:all|element:labels|visibility:off&format=png&key="
#sig_url = "&signature="
final_url = base_url + param_url + key
print(final_url)
r = requests.get(final_url)
print(r)
if r.status_code == 200:
with open(filename, 'wb') as img:
img.write(r.content)
This is my code, who have some suggestions to teach me how to add a signature. Although I have tried many times! Thank you every one

Answer 1

Since it sounds like you want to make a bunch of requests, I don't think you will be able to use the Sign a URL Now widget.
Luckily, you can generate your own signature for each request by following Google's URL signing sample code at https://developers.google.com/maps/documentation/streetview/get-api-key#sample-code-for-url-signing.
To do this, there are a number of steps you need to follow:
Strip the host and protocol scheme portions of the URL.
starting_url = 'https://maps.googleapis.com/maps/api/streetview?key=YOUR_API_KEY&location=ADDRESS&size=640x400'
stripped_url = '/maps/api/streetview?key=YOUR_API_KEY&location=ADDRESS&size=640x400'
Decode the URL-encoded private key (secret = secret key/URL signing secret generated for you in the credentials page).
decoded_key = base64.urlsafe_b64decode(secret)
Sign the stripped url request using HMAC-SHA1 (and encode the stripped URL in byte format - str.encode).
signature = hmac.new(decoded_key, str.encode(stripped_url), hashlib.sha1)
Encode the binary signature into base64 for use within a URL.
encoded_signature = base64.urlsafe_b64encode(signature.digest())
Append the Base64-encoded signature to the original unsigned request URL in the signature parameter, and decode from raw byte form.
final_url = starting_url + '&signature=' + encoded_signature
r = requests.get(final_url)

Answer 2

You can generate your digital signature through your GCP console. Here are the steps:
Build an unsigned request URL like:
https://maps.googleapis.com/maps/api/staticmap?center=40.714%2c%20-73.998&zoom=12&size=400x400&key=YOUR_API_KEY
Note: You need to include your API key on the the key parameter.
Get your signing secret from the Credentials page under Maps Static API in your GCP console. That is API & Services > Library > Maps Static API > Credential. You'll find your current signing secret under "Secret Generator" card
Generate a signed URL on the "Sign a URL now" card on the Credentials page under Maps Static API. All you need to do is paste your unsigned URL with your API key on the URL field. Then a signed URL will automatically be generated with your digital signature. You'll find your digital signature on the signature parameter on your generated signed URL.
Note: You'll have a unique signature for each of your requests. That means that you can only use a specific digital signature in a specific request.
Hope this helps!