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JavaScript

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.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

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

var http = new CkHttp();
http.AuthToken = "GMAIL-ACCESS-TOKEN";

var userId = "me";
http.SetUrlVar("userId",userId);

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

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

var sb = new CkStringBuilder();
success = http.QuickGetSb(url,sb);
if (success == false) {
    console.log(http.LastErrorText);
    return;
}

var json = new CkJsonObject();
json.LoadSb(sb);
json.EmitCompact = false;
console.log(json.Emit());

if (http.LastStatus !== 200) {
    console.log("Failed.");
    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.

var json2 = new CkJsonObject();

var i = 0;
var numMessages = json.SizeOfArray("messages");
while ((i < numMessages)) {
    json.I = i;
    var id = json.StringOf("messages[i].id");
    json2.I = 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"
var labelId = "Label_43";
json2.UpdateString("addLabelIds[0]",labelId);
json2.UpdateNewArray("removeLabelIds");

json2.EmitCompact = false;
console.log(json2.Emit());

// Send the batchModify
url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages/batchModify";
var resp = new CkHttpResponse();
success = http.HttpJson("POST",url,json2,"application/json",resp);
if (success == false) {
    console.log(http.LastErrorText);
    return;
}

console.log("status = " + resp.StatusCode);

// A 204 response status indicate success.
if (resp.StatusCode !== 204) {
    console.log(resp.BodyStr);
    console.log("Failed.");
    return;
}

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

console.log("BatchModify success!");