Tcl

POP3 Auto-Refresh Office365 Access Token

See more Office365 Examples

Demonstrates how to automatically recover from an expired OAuth2 access token when OAuth2 authentication fails in the POP3 protocol. If the server responds with "-ERR Authentication failure: unknown user name or bad password.", then we refresh the access token and retry. Tcl

load ./chilkat.dll

set success 0

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

set mailman [new_CkMailMan]

CkMailMan_put_MailHost $mailman "outlook.office365.com"
CkMailMan_put_MailPort $mailman 995
CkMailMan_put_PopSsl $mailman 1

# Use your O365 email address here.
CkMailMan_put_PopUsername $mailman "OFFICE365_EMAIL_ADDRESS"

# When using OAuth2 authentication, leave the password empty.
CkMailMan_put_PopPassword $mailman ""

# Load our previously obtained OAuth2 access token.
set jsonToken [new_CkJsonObject]

set success [CkJsonObject_LoadFile $jsonToken "qa_data/tokens/office365.json"]
if {$success == 0} then {
    puts [CkJsonObject_lastErrorText $jsonToken]
    delete_CkMailMan $mailman
    delete_CkJsonObject $jsonToken
    exit
}

CkMailMan_put_OAuth2AccessToken $mailman [CkJsonObject_stringOf $jsonToken "access_token"]

# Make the TLS connection to the outlook.office365.com POP3 server.
set success [CkMailMan_Pop3Connect $mailman]
if {$success != 1} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    delete_CkJsonObject $jsonToken
    exit
}

# Authenticate using XOAUTH2
set success [CkMailMan_Pop3Authenticate $mailman]
if {$success != 1} then {
    # If we're still connected to the mail server, then it means the server sent a non-success response,
    # Such as:  -ERR Authentication failure: unknown user name or bad password.
    if {[CkMailMan_get_IsPop3Connected $mailman] == 1} then {

        # Refresh the OAuth2 access token, and if successful, save the new (refreshed) access token and try authenticating again.
        set oauth2 [new_CkOAuth2]

        # Use your actual Directory (tenant) ID instead of "112d7ed6-71bf-4eba-a866-738364321bfc"
        CkOAuth2_put_TokenEndpoint $oauth2 "https://login.microsoftonline.com/112d7ed6-71bf-4eba-a866-738364321bfc/oauth2/v2.0/token"

        # Replace these with your Azure App Registration's actual values.
        CkOAuth2_put_ClientId $oauth2 "CLIENT_ID"
        CkOAuth2_put_ClientSecret $oauth2 "CLIENT_SECRET"

        # Get the "refresh_token"
        CkOAuth2_put_RefreshToken $oauth2 [CkJsonObject_stringOf $jsonToken "refresh_token"]

        # Send the HTTP POST to refresh the access token..
        set success [CkOAuth2_RefreshAccessToken $oauth2]
        if {$success != 1} then {
            puts [CkOAuth2_lastErrorText $oauth2]
            delete_CkMailMan $mailman
            delete_CkJsonObject $jsonToken
            delete_CkOAuth2 $oauth2
            exit
        }

        puts "New access token: [CkOAuth2_accessToken $oauth2]"
        puts "New refresh token: [CkOAuth2_refreshToken $oauth2]"

        # Update the JSON with the new tokens.
        CkJsonObject_UpdateString $jsonToken "access_token" [CkOAuth2_accessToken $oauth2]
        CkJsonObject_UpdateString $jsonToken "refresh_token" [CkOAuth2_refreshToken $oauth2]

        # Save the new JSON access token response to a file.
        set sbJson [new_CkStringBuilder]

        CkJsonObject_put_EmitCompact $jsonToken 0
        CkJsonObject_EmitSb $jsonToken $sbJson
        CkStringBuilder_WriteFile $sbJson "qa_data/tokens/office365.json" "utf-8" 0

        puts "New Access Token = [CkOAuth2_accessToken $oauth2]"

        # Update the mailman with the new access token.
        CkMailMan_put_OAuth2AccessToken $mailman [CkOAuth2_accessToken $oauth2]

        # Retry the authentication.
        set success [CkMailMan_Pop3Authenticate $mailman]
        if {$success == 0} then {
            puts [CkMailMan_lastErrorText $mailman]
            delete_CkMailMan $mailman
            delete_CkJsonObject $jsonToken
            delete_CkOAuth2 $oauth2
            delete_CkStringBuilder $sbJson
            exit
        }

    }     else {
        puts [CkMailMan_lastErrorText $mailman]
        delete_CkMailMan $mailman
        delete_CkJsonObject $jsonToken
        delete_CkOAuth2 $oauth2
        delete_CkStringBuilder $sbJson
        exit
    }

}

# Find out how many emails are on the server..
set numEmails [CkMailMan_CheckMail $mailman]
if {$numEmails < 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    delete_CkJsonObject $jsonToken
    delete_CkOAuth2 $oauth2
    delete_CkStringBuilder $sbJson
    exit
}

# Examine the POP3 session log:
puts [CkMailMan_pop3SessionLog $mailman]

# The POP3 session log will look something like this:

# **** Connected to outlook.office365.com:995
# < +OK The Microsoft Exchange POP3 service is ready. [QwBIADIAUABSADEANgBDAEEAMAAwADEAMgAuAG4AYQBtAHAAcgBkADEANgAuAHAAcgBvAGQALgBvAHUAdABsAG8AbwBrAC4AYwBvAG0A]
# > AUTH XOAUTH2
# < + 
# > <base64 string in XOAUTH2 format>
# < -ERR Authentication failure: unknown user name or bad password.
# > AUTH XOAUTH2
# < + 
# > <base64 string in XOAUTH2 format>
# < +OK User successfully authenticated.
# > STAT
# < +OK 248 46637086

# End the POP3 session and close the connection to the GMail server.
set success [CkMailMan_Pop3EndSession $mailman]
if {$success != 1} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    delete_CkJsonObject $jsonToken
    delete_CkOAuth2 $oauth2
    delete_CkStringBuilder $sbJson
    exit
}

puts "Finished."

delete_CkMailMan $mailman
delete_CkJsonObject $jsonToken
delete_CkOAuth2 $oauth2
delete_CkStringBuilder $sbJson