PowerBuilder

IMAP Auto-Refresh Office365 Access Token

See more Office365 Examples

Demonstrates how to automatically recover from an expired access token when OAuth2 authentication fails in the IMAP protocol. If the server responds with "NO AUTHENTICATE failed.", then we refresh the access token and retry. PowerBuilder

integer li_rc
integer li_Success
oleobject loo_JsonToken
oleobject loo_Imap
string ls_LoginLastErrorText
oleobject loo_Oauth2
oleobject loo_SbJson

li_Success = 0

// An Office365 OAuth2 access token must first be obtained prior
// to running this code.

// Getting the OAuth2 access token for the 1st time requires the O365 account owner's 
// interactive authorizaition via a web browser.  Afterwards, the access token
// can be repeatedly refreshed automatically.

// See the following examples for getting and refreshing an OAuth2 access token

// Get Office365 SMTP/IMAP/POP3 OAuth2 Access Token
// Refresh Office365 SMTP/IMAP/POP3 OAuth2 Access Token

// First get our previously obtained OAuth2 access token.
loo_JsonToken = create oleobject
li_rc = loo_JsonToken.ConnectToNewObject("Chilkat.JsonObject")
if li_rc < 0 then
    destroy loo_JsonToken
    MessageBox("Error","Connecting to COM object failed")
    return
end if
li_Success = loo_JsonToken.LoadFile("qa_data/tokens/office365.json")
if li_Success = 0 then
    Write-Debug "Failed to open the office365 OAuth JSON file."
    destroy loo_JsonToken
    return
end if

loo_Imap = create oleobject
li_rc = loo_Imap.ConnectToNewObject("Chilkat.Imap")

loo_Imap.Ssl = 1
loo_Imap.Port = 993

// Connect to the Office365 IMAP server.
li_Success = loo_Imap.Connect("outlook.office365.com")
if li_Success <> 1 then
    Write-Debug loo_Imap.LastErrorText
    destroy loo_JsonToken
    destroy loo_Imap
    return
end if

// Use OAuth2 authentication.
loo_Imap.AuthMethod = "XOAUTH2"

// Login using our username (i.e. email address) and the access token for the password.
li_Success = loo_Imap.Login("OFFICE365_EMAIL_ADDRESS",loo_JsonToken.StringOf("access_token"))
if li_Success <> 1 then
    ls_LoginLastErrorText = loo_Imap.LastErrorText

    // If we're still connected to the mail server, then it means the server sent a non-success response,
    // Such as:  NO AUTHENTICATE failed.
    if loo_Imap.IsConnected() = 1 then

        // Refresh the OAuth2 access token, and if successful, save the new (refreshed) access token and try authenticating again.
        loo_Oauth2 = create oleobject
        li_rc = loo_Oauth2.ConnectToNewObject("Chilkat.OAuth2")

        // Use your actual Directory (tenant) ID instead of "112d7ed6-71bf-4eba-a866-738364321bfc"
        loo_Oauth2.TokenEndpoint = "https://login.microsoftonline.com/112d7ed6-71bf-4eba-a866-738364321bfc/oauth2/v2.0/token"

        // Replace these with your Azure App Registration's actual values.
        loo_Oauth2.ClientId = "CLIENT_ID"
        loo_Oauth2.ClientSecret = "CLIENT_SECRET"

        // Get the "refresh_token"
        loo_Oauth2.RefreshToken = loo_JsonToken.StringOf("refresh_token")

        // Send the HTTP POST to refresh the access token..
        li_Success = loo_Oauth2.RefreshAccessToken()
        if li_Success <> 1 then
            Write-Debug loo_Oauth2.LastErrorText
            destroy loo_JsonToken
            destroy loo_Imap
            destroy loo_Oauth2
            return
        end if

        Write-Debug "New access token: " + loo_Oauth2.AccessToken
        Write-Debug "New refresh token: " + loo_Oauth2.RefreshToken

        // Update the JSON with the new tokens.
        loo_JsonToken.UpdateString("access_token",loo_Oauth2.AccessToken)
        loo_JsonToken.UpdateString("refresh_token",loo_Oauth2.RefreshToken)

        // Save the new JSON access token response to a file.
        loo_SbJson = create oleobject
        li_rc = loo_SbJson.ConnectToNewObject("Chilkat.StringBuilder")

        loo_JsonToken.EmitCompact = 0
        loo_JsonToken.EmitSb(loo_SbJson)
        loo_SbJson.WriteFile("qa_data/tokens/office365.json","utf-8",0)

        Write-Debug "New Access Token = " + loo_Oauth2.AccessToken

        // Retry the login.
        li_Success = loo_Imap.Login("OFFICE365_EMAIL_ADDRESS",loo_JsonToken.StringOf("access_token"))
        if li_Success = 0 then
            Write-Debug loo_Imap.LastErrorText
            destroy loo_JsonToken
            destroy loo_Imap
            destroy loo_Oauth2
            destroy loo_SbJson
            return
        end if

    else
        // Show the last error text for the call to Login
        Write-Debug ls_LoginLastErrorText
        destroy loo_JsonToken
        destroy loo_Imap
        destroy loo_Oauth2
        destroy loo_SbJson
        return
    end if

else
    Write-Debug "O365 OAuth authentication is successful."
end if

// Do something...
li_Success = loo_Imap.SelectMailbox("Inbox")
if li_Success <> 1 then
    Write-Debug loo_Imap.LastErrorText
    destroy loo_JsonToken
    destroy loo_Imap
    destroy loo_Oauth2
    destroy loo_SbJson
    return
end if

// Your application can continue to do other things in the IMAP session....

// When finished, logout and close the connection.
li_Success = loo_Imap.Logout()
li_Success = loo_Imap.Disconnect()

Write-Debug "Finished."


destroy loo_JsonToken
destroy loo_Imap
destroy loo_Oauth2
destroy loo_SbJson