(Lianja) Download Photo to a File

Assuming we have the ID of a Photo, this example demonstrates how to download the photo image data to a file.

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

// This example assumes a previously obtained an access token
loOauth2 = createobject("CkOAuth2")
loOauth2.AccessToken = "FACEBOOK-ACCESS-TOKEN"

loRest = createobject("CkRest")

// Connect to Facebook...
llSuccess = loRest.Connect("graph.facebook.com",443,.T.,.T.)
if (llSuccess <> .T.) then
    ? loRest.LastErrorText
    release loOauth2
    release loRest
    return
endif

// Provide the authentication credentials (i.e. the access key)
loRest.SetAuthOAuth2(loOauth2)

// Assumes we've already obtained a Photo ID.
lcPhotoId = "10210199026347451"

loSbPath = createobject("CkStringBuilder")
loSbPath.Append("/v2.7/")
loSbPath.Append(lcPhotoId)

// First we're going to get the photo informaton so we can get the URL of the image file data.
// Select the fields we want.
// See https://developers.facebook.com/docs/graph-api/reference/photo/
loRest.AddQueryParam("fields","id,album,images")

lcResponseJson = loRest.FullRequestNoBody("GET",loSbPath.GetAsString())
if (loRest.LastMethodSuccess <> .T.) then
    ? loRest.LastErrorText
    release loOauth2
    release loRest
    release loSbPath
    return
endif

loJson = createobject("CkJsonObject")
loJson.EmitCompact = .F.
loJson.Load(lcResponseJson)

// Show the JSON in human-readable format.
? loJson.Emit()

// Get the image URL.
lcImageUrl = loJson.StringOf("images[0].source")
? "Downloading from " + lcImageUrl

loSbImageUrl = createobject("CkStringBuilder")
loSbImageUrl.Append(lcImageUrl)

// Build the output local file path.
loSbToPath = createobject("CkStringBuilder")
loSbToPath.Append("qa_output/fb")
loSbToPath.Append(loJson.StringOf("id"))
llBCaseSensitive = .F.
if (loSbImageUrl.Contains(".jpg",llBCaseSensitive) = .T.) then
    loSbToPath.Append(".jpg")
else
    loSbToPath.Append(".png")
endif

? "Downloading to " + loSbToPath.GetAsString()

// Download using Chilkat HTTP.
loHttp = createobject("CkHttp")
llSuccess = loHttp.Download(lcImageUrl,loSbToPath.GetAsString())
if (llSuccess <> .T.) then
    ? loHttp.LastErrorText
else
    ? "Downloaded."
endif



release loOauth2
release loRest
release loSbPath
release loJson
release loSbImageUrl
release loSbToPath
release loHttp