Instant On - Wireless

Hello.

I want get status regularly batch job. (linux crontab)
but Instant On has no API.

I'm trying to call portal URL like an API.

ex)
site_id="...UUID 1..." # Static. part of personal portal URL
client_id="...UUID 2..." # Static? capture https://sso.arubainstanton.com/as/token.oauth2 Form Data (by Chrome Developper Tool)
# access_token="xxxxx" # Dynamic. capture https://sso.arubainstanton.com/as/token.oauth2 response (by Chrome Developper Tool) but expires_in:3600sec
refresh_token="zzzzz" # Dynamic. capture https://sso.arubainstanton.com/as/token.oauth2 response (by Chrome Developper Tool) Expiration date unknown

x=$( curl -s -X POST 'https://sso.arubainstanton.com/as/token.oauth2' \
  -d "grant_type=refresh_token&client_id=${client_id}&refresh_token=${refresh_token}" )
access_token=$( echo ${x} | jq -r .access_token )

x=$( curl -s -H "authorization: Bearer ${access_token}" \
  https://nb.portal.arubainstanton.com/api/sites/${site_id}/clientSummary )

refresh_token sometimes becomes unusable.
How Can I get refresh_token automaticaly? someone knows?

or Is it illegal to do this?  Please advise me.
regards.

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Takabumi Ichikawa
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