(DataFlex) Twitter - Application Only Authentication

Demonstrates how to get a Twitter OAuth2 token for application-only authentication.

This allows you to issue authenticated requests on behalf of the application itself (as opposed to on behalf of a specific user). You don’t have the context of an authenticated user and this means that any request to API for endpoints that require user context, such as posting Tweets, will not work. However, the set of endpoints that will still be available can have a higher rate limit.

Your app will be able to, for example:

• Pull user timelines;
• Access friends and followers of any account;
• Access lists resources;
• Search in Tweets;
• Retrieve any user information;

And it will not be able to:

• Post Tweets or other resources;
• Connect to Streaming endpoints;
• Search for users;
• Use any geo endpoint;
• Access Direct Messages or account credentials;

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    String sConsumerKey
    String sConsumerSecret
    Handle hoHttp
    Variant vReq
    Handle hoReq
    Variant vResp
    Handle hoResp
    Handle hoJson
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // It requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Note: Define your Twitter apps at https://apps.twitter.com/

    // We're going to send an HTTPS POST that looks like this:

    // POST /oauth2/token HTTP/1.1
    // Host: api.twitter.com
    // User-Agent: My Twitter App v1.0.23
    // Authorization: Basic eHZ6MWV2RlM0d0VFUFRHRUZQSEJvZzpMOHFxOVBaeVJn
    //                      NmllS0dFS2hab2xHQzB2SldMdzhpRUo4OERSZHlPZw==
    // Content-Type: application/x-www-form-urlencoded;charset=UTF-8
    // Content-Length: 29
    // Accept-Encoding: gzip
    // 
    // grant_type=client_credentials

    // Update these values with your consumer key and secret (also known as API key and API secret).
    Move "TWITTER_CONSUMER_KEY" To sConsumerKey
    Move "TWITTER_CONSUMER_SECRET" To sConsumerSecret

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    Set ComBasicAuth Of hoHttp To True
    Set ComLogin Of hoHttp To sConsumerKey
    Set ComPassword Of hoHttp To sConsumerSecret

    Get Create (RefClass(cComChilkatHttpRequest)) To hoReq
    If (Not(IsComObjectCreated(hoReq))) Begin
        Send CreateComObject of hoReq
    End
    Send ComAddParam To hoReq "grant_type" "client_credentials"

    Get pvComObject of hoReq to vReq
    Get ComPostUrlEncoded Of hoHttp "https://api.twitter.com/oauth2/token" vReq To vResp
    If (IsComObject(vResp)) Begin
        Get Create (RefClass(cComChilkatHttpResponse)) To hoResp
        Set pvComObject Of hoResp To vResp
    End
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComStatusCode Of hoResp To iTemp1
    Showln "Response Status Code: " iTemp1

    Get ComStatusCode Of hoResp To iTemp1
    If (iTemp1 <> 200) Begin
        Showln "Expected a 200 response status code for success."
        Get ComBodyStr Of hoResp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // We should get a JSON response like this:

    // {
    //     "token_type":"bearer",
    //     "access_token":"..."
    // }

    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComBodyStr Of hoResp To sTemp1
    Get ComLoad Of hoJson sTemp1 To iSuccess

    Get ComStringOf Of hoJson "access_token" To sTemp1
    Showln "Access token = " sTemp1

    Send Destroy of hoResp


End_Procedure