(Go) Get GMail Message Metadata

Demonstrates how to get the metadata for each message in a list of message IDs.

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

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

    http := chilkat.NewHttp()

    http.SetAuthToken("ACCESS_TOKEN")

    http.SetAccept("application/json")

    // Let's say we have the following JSON containing a list of message ID's

    // {
    //   "messages": [
    //     {
    //       "id": "1712bc1dc22da2a2",
    //       "threadId": "1712bc1dc22da2a2"
    //     },
    //     {
    //       "id": "1712b94fa2168040",
    //       "threadId": "1712b94fa2168040"
    //     },
    //     {
    //       "id": "1711e4bd96ded05e",
    //       "threadId": "1711e4bd96ded05e"
    //     },
    //     {
    //       "id": "1711de0d119e751e",
    //       "threadId": "1711de0d119e751e"
    //     },
    //     {
    //       "id": "1711c81a43050f59",
    //       "threadId": "1711c81a43050f59"
    //     },
    //     {
    //       "id": "1711c2c1516abce5",
    //       "threadId": "1711c2c1516abce5"
    //     },
    //     {
    //       "id": "1711c161e655c915",
    //       "threadId": "1711c161e655c915"
    //     },
    //     {
    //       "id": "171199c6e454558c",
    //       "threadId": "171199c6e454558c"
    //     },
    //     {
    //       "id": "17119474c8aa248e",
    //       "threadId": "17119474c8aa248e"
    //     }
    //   ],
    //   "nextPageToken": "16710921492249671162",
    //   "resultSizeEstimate": 309
    // }

    // Normally your program would have the above JSON in a string variable (obtained from a previous call to get
    // a list of message IDs from a GMail mailbox).  In this example, we'll load the JSON from a file.
    jsonMsgIds := chilkat.NewJsonObject()
    success := jsonMsgIds.LoadFile("qa_data/json/gmail_message_ids.json")

    var id *string = new(string)
    i := 0
    count_i := jsonMsgIds.SizeOfArray("messages")
    for i < count_i {
        jsonMsgIds.SetI(i)
        id = jsonMsgIds.StringOf("messages[i].id")

        // Get the metadata for this message ID.
        http.SetUrlVar("id",*id)

        resp := http.QuickRequest("GET","https://www.googleapis.com/gmail/v1/users/userId/messages/{$id}?format=metadata")
        if http.LastMethodSuccess() != true {
            fmt.Println(http.LastErrorText())
            http.DisposeHttp()
            jsonMsgIds.DisposeJsonObject()
            return
        }

        fmt.Println("Response Status Code: ", resp.StatusCode())

        jsonResponse := chilkat.NewJsonObject()
        jsonResponse.Load(resp.BodyStr())
        jsonResponse.SetEmitCompact(false)
        fmt.Println(*jsonResponse.Emit())

        if resp.StatusCode() != 200 {
            fmt.Println("Failed.")
            resp.DisposeHttpResponse()
            http.DisposeHttp()
            jsonMsgIds.DisposeJsonObject()
            jsonResponse.DisposeJsonObject()
            return
        }

        resp.DisposeHttpResponse()

        i = i + 1
    }

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    http.DisposeHttp()
    jsonMsgIds.DisposeJsonObject()
    jsonResponse.DisposeJsonObject()