(Lianja) Download GMail Message Attachment by ID

Demonstrates how to download a GMail email attachment by the attachment ID.

For more information, see https://developers.google.com/gmail/api/v1/reference/users/messages/attachments/get

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.

loHttp = createobject("CkHttp")

loHttp.AuthToken = "ACCESS_TOKEN"
loHttp.Accept = "application/json"

// See the following example:  Get GMail Message (format=full)
// It shows how to download an email by message ID, and it shows how to parse the JSON
// response which includes attachment names, ids, and other information.

// This example will assume we already have the attachment id and filename.

// This is the attachment ID for a file named "helloWorld.pdf".
lcAttachmentId = "ANGjdJ-oy3aCuZISJKLAhUdaEksCEklbAPyMaWzFgqOMGbPCRkgwgeu_Kttd99C17OBTHROkDZGekibTKWXGfscB5ww7fw4E65_V1dQ-jHhb2TD1Cdm58-BbNw2iDxzptco8iILPiSnLLfFn5Ps7nsRcxHaGTt3r0yqFKCuIYNnPK1vM04BXI_cfzo-HnI4I3tD6oHNHOGVQrL01MdShFQjPELPUjXM8z1qs7Kom-QyvV1iOldUN-66UuhynsmDX-CMM5TIdB-8KD_lmdhf-0DqG8JnCA20XpXyfqwS8XFkPA-t-QSjb7SdkHQFtQ4lz2PcBREFzZ2eI5j0l0Y_dQHRPYTeMwkVl1yl4MfFT4C4iso3VSF-eqaIjiFCbXKCFNyeEIW5WFsv189dhlSqU"

lcMessageId = "1712bc1dc22da2a2"

loHttp.SetUrlVar("messageId",lcMessageId)
loHttp.SetUrlVar("attachmentId",lcAttachmentId)

lcUrl = "https://www.googleapis.com/gmail/v1/users/userId/messages/{$messageId}/attachments/{$attachmentId}"

// When we download, the response is JSON that contains the attachment data base64url encoded, like this:
// {
//  "size": 934,
//  "data": "JVBERi0xLjM ... CiUlRU9GCg=="
// }

lcOutputFilePath = "qa_output/helloWorld.pdf"

// Download into a StringBuilder.
loSbJson = createobject("CkStringBuilder")
llSuccess = loHttp.DownloadSb(lcUrl,"utf-8",loSbJson)
if (llSuccess = .F.) then
    ? loHttp.LastErrorText
    release loHttp
    release loSbJson
    return
endif

if (loHttp.LastStatus <> 200) then
    // Something failed.
    // the JSON contains an error message.
    ? loSbJson.GetAsString()
    release loHttp
    release loSbJson
    return
endif

// Load into a Chilkat JSON object.
loJson = createobject("CkJsonObject")
llSuccess = loJson.LoadSb(loSbJson)

// Extract the base64url data into a BinData.
loBd = createobject("CkBinData")
llSuccess = loJson.BytesOf("data","base64url",loBd)

// Save the data to a file.
llSuccess = loBd.WriteFile("qa_output/helloWorld.pdf")

? "Success."


release loHttp
release loSbJson
release loJson
release loBd