(Visual FoxPro) Facebook Upload Photo from Local File

Uploads a new photo with a caption from a local file.

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

LOCAL loHttp
LOCAL loReq
LOCAL lnSuccess
LOCAL loResp
LOCAL lcResponseJson

* This example assumes Chilkat HTTP to have been previously unlocked.
* See Global Unlock Sample for sample code.

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Http')
loHttp = CreateObject('Chilkat.Http')

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.HttpRequest')
loReq = CreateObject('Chilkat.HttpRequest')
loReq.HttpVerb = "POST"
loReq.ContentType = "multipart/form-data"
loReq.Path = "/v2.7/me/photos"

* Use the previously obtained access token.
* Note: The publish_actions scope is required to upload a photo.
loReq.AddHeader("Authorization","Bearer FACEBOOK-ACCESS-TOKEN")

* Send an "Expect: 100-continue" header in the request.
* This causes the HTTP server to end a 100-continue response
* immediately after receiving the HTTP header.  The client
* (Chilkat) will receive this intermediate response, and if
* it's not an error response, it knows that the HTTP server will
* accept the data that is forthcoming.
* The alternative is to get an error response after trying to upload
* the entire contents of the files.
loReq.AddHeader("Expect","100-continue")

* Set a photo caption.
loReq.AddParam("caption","Here are some penguins!")

* Additional parameters can be added to the request by 
* calling AddParam once per parameter.  
* See https://developers.facebook.com/docs/graph-api/reference/user/photos
* for more information about other optional parameters.

* Indicate the local file to be uploaded.
lnSuccess = loReq.AddFileForUpload("source","qa_data/jpg/penguins2.jpg")
IF (lnSuccess <> 1) THEN
    ? loReq.LastErrorText
    RELEASE loHttp
    RELEASE loReq
    CANCEL
ENDIF

* Upload the image file..
loResp = loHttp.SynchronousRequest("graph.facebook.com",443,1,loReq)
IF (loHttp.LastMethodSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loHttp
    RELEASE loReq
    CANCEL
ENDIF

* Examine the response body:
lcResponseJson = loResp.BodyStr
? lcResponseJson

* The response contains JSON, such as this:
* {"id":"10210224963435862","post_id":"10224048320139890_10210224963435862"}

RELEASE loResp

RELEASE loHttp
RELEASE loReq