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Go

BatchModify - Add a Label to each Message in Search Results

See more GMail REST API Examples

Searchs GMail for messages meeting a criteria and adds a label to each message found.

Chilkat Go Downloads

Go
    success := false

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

    http := chilkat.NewHttp()
    http.SetAuthToken("GMAIL-ACCESS-TOKEN")

    userId := "me"
    http.SetUrlVar("userId",userId)

    query := "subject:questions"
    http.SetUrlVar("query",query)

    url := "https://www.googleapis.com/gmail/v1/users/{$userId}/messages?q={$query}"

    sb := chilkat.NewStringBuilder()
    success = http.QuickGetSb(url,sb)
    if success == false {
        fmt.Println(http.LastErrorText())
        http.DisposeHttp()
        sb.DisposeStringBuilder()
        return
    }

    json := chilkat.NewJsonObject()
    json.LoadSb(sb)
    json.SetEmitCompact(false)
    fmt.Println(*json.Emit())

    if http.LastStatus() != 200 {
        fmt.Println("Failed.")
        http.DisposeHttp()
        sb.DisposeStringBuilder()
        json.DisposeJsonObject()
        return
    }

    // If successful, the received JSON looks like this:
    // {
    //   "messages": [
    //     {
    //       "id": "166f583051d36144",
    //       "threadId": "166f583051d36144"
    //     },
    //     {
    //       "id": "166f5815e1f36144",
    //       "threadId": "166f5815e1f36144"
    //     },
    // 	...
    //     {
    //       "id": "166f580639e36144",
    //       "threadId": "166f580639e36144"
    //     },
    //     {
    //       "id": "15dbc2e28ec789c6",
    //       "threadId": "15dbc2e28ec789c6"
    //     }
    //   ],
    //   "nextPageToken": "13434766102274844688",
    //   "resultSizeEstimate": 103
    // }
    // 

    // Next, we'll be sending an HTTP POST to add the label "questions" to each message in the
    // search results.  The JSON to be sent for the batchModify is this:

    // 	{
    // 	  "ids": [
    // 	    string
    // 	  ],
    // 	  "addLabelIds": [
    // 	    string
    // 	  ],
    // 	  "removeLabelIds": [
    // 	    string
    // 	  ]
    // 	}

    // We'll omit "removeLabelIds" because we're not removing any labels.
    // We are parsing the JSON search results, and at the same time building the batchModify JSON.

    json2 := chilkat.NewJsonObject()

    i := 0
    numMessages := json.SizeOfArray("messages")
    for (i < numMessages) {
        json.SetI(i)
        id := json.StringOf("messages[i].id")
        json2.SetI(i)
        json2.UpdateString("ids[i]",*id)
        i = i + 1
    }

    // We need the id of the label (not the name).
    // I know the name of the label is "questions", but I need to know the id.
    // See this example: Get Label Id by Name
    // The id of my label named "questions" is "Label_43"
    labelId := "Label_43"
    json2.UpdateString("addLabelIds[0]",labelId)
    json2.UpdateNewArray("removeLabelIds")

    json2.SetEmitCompact(false)
    fmt.Println(*json2.Emit())

    // Send the batchModify
    url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages/batchModify"
    resp := chilkat.NewHttpResponse()
    success = http.HttpJson("POST",url,json2,"application/json",resp)
    if success == false {
        fmt.Println(http.LastErrorText())
        http.DisposeHttp()
        sb.DisposeStringBuilder()
        json.DisposeJsonObject()
        json2.DisposeJsonObject()
        resp.DisposeHttpResponse()
        return
    }

    fmt.Println("status = ", resp.StatusCode())

    // A 204 response status indicate success.
    if resp.StatusCode() != 204 {
        fmt.Println(resp.BodyStr())
        fmt.Println("Failed.")
        http.DisposeHttp()
        sb.DisposeStringBuilder()
        json.DisposeJsonObject()
        json2.DisposeJsonObject()
        resp.DisposeHttpResponse()
        return
    }

    // The 204 response has an empty response body..

    fmt.Println("BatchModify success!")

    http.DisposeHttp()
    sb.DisposeStringBuilder()
    json.DisposeJsonObject()
    json2.DisposeJsonObject()
    resp.DisposeHttpResponse()