(Node.js) IMAP Search with THREAD Semantics

Demonstrates how to search an IMAP mailbox and return message numbers grouped together in parent/child relationships based on which messages are replies to others.

Note: This example requires Chilkat v9.5.0.77 or greater.

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 imap = new chilkat.Imap();

    // Connect to your IMAP server and authenticate..
    imap.Ssl = true;
    imap.Port = 993;
    var success = imap.Connect("imap.mail.us-west-2.awsapps.com");
    if (success !== true) {
        console.log(imap.LastErrorText);
        return;
    }

    success = imap.Login("myLogin","myPassword");
    if (success !== true) {
        console.log(imap.LastErrorText);
        return;
    }

    // Select a mailbox
    success = imap.SelectMailbox("Inbox");
    if (success !== true) {
        console.log(imap.LastErrorText);
        return;
    }

    // Search for all message having the letter 'a' somewhere in the Subject,
    // and return the messages as JSON.
    // json: JsonObject
    var json = imap.ThreadCmd("REFERENCES","UTF-8","SUBJECT a",true);
    if (imap.LastMethodSuccess == false) {
        console.log(imap.LastErrorText);
        return;
    }

    // The IMAP server will return a raw response with a format such as this:  (2)(3 6 (4 23)(44 7 96))

    // In tree form, it's like this:
    // 
    //             -- 2
    //             -- 3
    //                 \-- 6
    //                    |-- 4
    //                    |      \-- 23
    //                    |
    //                    |-- 44
    //                               \-- 7
    //                                       \-- 96
    // 

    // It means there are 2 main threads returned, but the 2nd thread splits into two sub-threads.
    // In total, we can think of it as 3 threads -- 2 main threads (with no parents) and one sub-thread w/ a parent.
    // 
    // - The 1st thread contains the message 2, and has no parent thread.
    // - The 2nd thread contains the messages 3, 6, 4, 23, and has no parent thread.
    // - The 3rd thread contains the messages 44, 7, 96 and the parent thread is message 6.
    // 

    // (Yes, this is all highly confusing...)

    // Chilkat will return the above sample response as JSON that looks like this:

    // {
    //   "threads": [
    //     [2],
    //     [3, 6, [4, 23], [44, 7, 96]]
    //   ]
    // }
    // 

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON
    // In this case, the online tool can help you get a feel for how to write the JSON parsing code..

    var numThreads = json.SizeOfArray("threads");
    console.log("The total number of top-level threads is " + numThreads);

    // Let's say we wanted to get the messages in the thread 3, 6, 4, 23.
    // We always follow the 1st branch to the bottom, ignoring the other branches.
    // For example, if we had  [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]
    // then the thread would be 3, 5, 4, 43, 55, 56, 57

    // For testing, let's substitute the response from the IMAP server with this sample:
    json.Load("{\"threads\": [[2], [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]]}");

    // Begin with the 2nd top-level thread, which is at index 1.
    console.log("Following the 2nd top level thread...");
    // arr: JsonArray
    var arr = json.ArrayOf("threads[1]");
    var threadSize = arr.Size;
    var i = 0;
    while (i < threadSize) {
        // Do we have an array or integer at this position?
        if (arr.TypeAt(i) == 4) {
            // This is a sub-array.
            // subArr: JsonArray
            var subArr = arr.ArrayAt(i);

            // Follow the sub-array starting at the 1st position..
            arr = subArr;
            i = 0;
            threadSize = arr.Size;
        }
        else {
            // Must be a single integer.
            console.log(arr.IntAt(i));
            i = i+1;
        }

    }

    // The output is:
    // 
    // Following the 2nd top level thread...
    // 3
    // 5
    // 4
    // 23
    // 55
    // 56
    // 57

}

chilkatExample();