(PureBasic) Yahoo Mail OAuth2 Access Token for Desktop App

See more Yahoo Mail Examples

Note: This example requires Chilkat v10.1.2 or greater.

For more information, see https://developer.yahoo.com/oauth2/guide/

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkOAuth2.pb"
IncludeFile "CkStringBuilder.pb"

Procedure ChilkatExample()

    ; First, you must define your app in Yahoo Developer (https://developer.yahoo.com/apps/) like this:

    ; 

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

    oauth2.i = CkOAuth2::ckCreate()
    If oauth2.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Your applicaton must use your own public web server as an intermediate
    ; to receive and forward the redirect to localhost.
    ; See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost
    CkOAuth2::setCkAppCallbackUrl(oauth2, "https://yourwebserver.com/oauth_redirect")
    CkOAuth2::setCkListenPort(oauth2, 3017)

    CkOAuth2::setCkAuthorizationEndpoint(oauth2, "https://api.login.yahoo.com/oauth2/request_auth")
    CkOAuth2::setCkTokenEndpoint(oauth2, "https://api.login.yahoo.com/oauth2/get_token")

    ; Replace these with actual values.
    CkOAuth2::setCkClientId(oauth2, "CLIENT_ID")
    CkOAuth2::setCkClientSecret(oauth2, "CLIENT_SECRET")

    ; Do not send the "scope" query param for Yahoo OAuth2.
    CkOAuth2::setCkUncommonOptions(oauth2, "NO_OAUTH2_SCOPE")

    ; Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
    url.s = CkOAuth2::ckStartAuth(oauth2)
    If CkOAuth2::ckLastMethodSuccess(oauth2) <> 1
        Debug CkOAuth2::ckLastErrorText(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    Debug "url = " + url

    ; Launch the default browser on the system and navigate to the url.
    ; The LaunchBrowser method was added in Chilkat v10.1.2.
    success.i = CkOAuth2::ckLaunchBrowser(oauth2,url)
    If success = 0
        Debug CkOAuth2::ckLastErrorText(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    ; Wait for the user to approve or deny authorization in the browser.
    numMsWaited.i = 0
    While (numMsWaited < 90000) AND (CkOAuth2::ckAuthFlowState(oauth2) < 3)
        CkOAuth2::ckSleepMs(oauth2,100)
        numMsWaited = numMsWaited + 100
    Wend

    ; If the browser does not respond within the specified time, AuthFlowState will be:
    ; 
    ; 1: Waiting for Redirect - The OAuth2 background thread is waiting for the browser's redirect request.
    ; 2: Waiting for Final Response - The thread is awaiting the final access token response.
    ; In either case, cancel the background task initiated by StartAuth.

    If CkOAuth2::ckAuthFlowState(oauth2) < 3
        CkOAuth2::ckCancel(oauth2)
        Debug "No response from the browser!"
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    ; Check AuthFlowState to determine if authorization was granted, denied, or failed:
    ; 
    ; 3: Success - OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
    ; 4: Access Denied - OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
    ; 5: Failure - OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

    If CkOAuth2::ckAuthFlowState(oauth2) = 5
        Debug "OAuth2 failed to complete."
        Debug CkOAuth2::ckFailureInfo(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    If CkOAuth2::ckAuthFlowState(oauth2) = 4
        Debug "OAuth2 authorization was denied."
        Debug CkOAuth2::ckAccessTokenResponse(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    If CkOAuth2::ckAuthFlowState(oauth2) <> 3
        Debug "Unexpected AuthFlowState:" + Str(CkOAuth2::ckAuthFlowState(oauth2))
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    ; Save the full JSON access token response to a file.
    sbJson.i = CkStringBuilder::ckCreate()
    If sbJson.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkStringBuilder::ckAppend(sbJson,CkOAuth2::ckAccessTokenResponse(oauth2))
    CkStringBuilder::ckWriteFile(sbJson,"qa_data/tokens/yahooMail.json","utf-8",0)

    ; The saved JSON response looks like this:

    ; {
    ;   "access_token": "kCVQdnOdul...LHucA--",
    ;   "refresh_token": "AIenVXETSo0jklFBVkPS8vVm8E.Ej9ToRG.xDbDYmZ65WIs5t6CZhDrD",
    ;   "expires_in": 3600,
    ;   "token_type": "bearer",
    ;   "xoauth_yahoo_guid": "HGDQCVF5JB4YDOWHITQJFBHCWA"
    ; }

    Debug "OAuth2 authorization granted!"
    Debug "Access Token: " + CkOAuth2::ckAccessToken(oauth2)


    CkOAuth2::ckDispose(oauth2)
    CkStringBuilder::ckDispose(sbJson)


    ProcedureReturn
EndProcedure