CkPython

Refresh HMRC OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to refresh an HMRC access token. CkPython

import sys
import chilkat

success = False

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# See Get HMRC Access Token 
# for sample code showing how to obtain a HMRC access token for desktop apps.

# It is assumed we previously obtained an OAuth2 access token for HMRC.

jsonToken = chilkat.CkJsonObject()
success = jsonToken.LoadFile("qa_data/tokens/hmrc.json")
if (success != True):
    print("Failed to load hmrc.json")
    sys.exit()

# The access token JSON looks something like this:

# {
#   "token_type": "Bearer",
#   "scope": "user_impersonation",
#   "expires_in": "3599",
#   "ext_expires_in": "0",
#   "expires_on": "1524783438",
#   "not_before": "1524779538",
#   "resource": "https://mydomain.api.crm.dynamics.com",
#   "access_token": "...",
#   "refresh_token": "...",
#   "id_token": "..."
# }

oauth2 = chilkat.CkOAuth2()

oauth2.put_TokenEndpoint("https://test-api.service.hmrc.gov.uk/oauth/token")

# Replace these with actual values.
oauth2.put_ClientId("HMRC-CLIENT-ID")
oauth2.put_ClientSecret("HMRC-CLIENT-SECRET")

# Get the "refresh_token"
oauth2.put_RefreshToken(jsonToken.stringOf("refresh_token"))

# Send the HTTP POST to refresh the access token..
success = oauth2.RefreshAccessToken()
if (success != True):
    print(oauth2.lastErrorText())
    sys.exit()

# Load the access token response into the json object 
jsonToken.Load(oauth2.accessTokenResponse())

# If an "expires_on" member does not exist, then add the JSON member by
# getting the current system date/time and adding the "expires_in" seconds.
# This way we'll know when the token expires.
if (jsonToken.HasMember("expires_on") == False):
    dtExpire = chilkat.CkDateTime()
    dtExpire.SetFromCurrentSystemTime()
    dtExpire.AddSeconds(jsonToken.IntOf("expires_in"))
    jsonToken.AppendString("expires_on",dtExpire.getAsUnixTimeStr(False))

# Save the new JSON access token response to a file.
# The access + refresh tokens contained in this JSON will be needed for the next refresh.
sbJson = chilkat.CkStringBuilder()
jsonToken.put_EmitCompact(False)
jsonToken.EmitSb(sbJson)
sbJson.WriteFile("qa_data/tokens/hmrc.json","utf-8",False)

print("OAuth2 authorization granted!")
print("New Access Token = " + oauth2.accessToken())