(Node.js) BatchModify - Add a Label to each Message in Search Results

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

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var success;

    var http = new chilkat.Http();
    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 chilkat.StringBuilder();
    success = http.QuickGetSb(url,sb);
    if (success !== true) {
        console.log(http.LastErrorText);
        return;
    }

    var json = new chilkat.JsonObject();
    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 chilkat.JsonObject();

    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";
    // resp: HttpResponse
    var resp = http.PostJson3(url,"application/json",json2);
    if (http.LastMethodSuccess !== true) {
        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!");

}

chilkatExample();