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Tcl

Get XOAUTH2 Access Token from Google OAuth 2.0 Authorization Server

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Obtains an OAUTH2 access token from the Google OAuth 2.0 Authorization Server. This is for Server to server applications using Google API's that need an access token. See https://developers.google.com/accounts/docs/OAuth2ServiceAccount

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

set success 0

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

set http [new_CkHttp]

# --------------------------------------------------------------------------------
# For a step-by-step guide for setting up your Google Workspace service account,
# see Setup Google Workspace Account for Sending SMTP GMail from a Service Account
# --------------------------------------------------------------------------------
# Begin by loading your Google service account key (.p12)
set cert [new_CkCert]

set success [CkCert_LoadPfxFile $cert "c:/someDirectory/keys/chilkat25-cbd7b42afbd8.p12" "notasecret"]
if {$success != 1} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkHttp $http
    delete_CkCert $cert
    exit
}

# The ISS is your service account email address ending in gserviceaccount.com.
set iss "chilkatsvc@chilkat25.iam.gserviceaccount.com"

# The scope is always the following string:
set scope "https://mail.google.com/"

# The sub is your company email address
set oauth_sub "bob@yourcompany.com"

# The access token is valid for this number of seconds.
set numSec 3600

set accessToken [CkHttp_g_SvcOauthAccessToken $http $iss $scope $oauth_sub $numSec $cert]
if {[CkHttp_get_LastMethodSuccess $http] != 1} then {
    puts [CkHttp_lastErrorText $http]
    delete_CkHttp $http
    delete_CkCert $cert
    exit
} else {
    puts "access token: $accessToken"
}

# The access token allows us to send unlimited emails while it's valid. Once it expires, we must obtain and use a new one.

delete_CkHttp $http
delete_CkCert $cert