Update (Javascript) collection column in MongoDB with array

Question

When attempting to update a mongoDB collection with an array as the value, the update fails silently.

This does not work:

var arr = ["test","test1","test2"];
$.ajax('http://my.mongodb.com/collection?id=80a2c727de877ac9' , {
      type: "PUT",
      contentType: "application/json",
      data: JSON.stringify({
        mykey: arr
      }),
      success: function() {
        // Do something
      }, 
      error: function(xhr) {
        console.log(xhr.responseText);
      }
    });

This does:

$.ajax('http://my.mongodb.com/collection?id=80a2c727de877ac9' , {
      type: "PUT",
      contentType: "application/json",
      data: JSON.stringify({
        mykey: "test"
      }),
      success: function() {
        // Do something
      }, 
      error: function(xhr) {
        console.log(xhr.responseText);
      }
    });

Answer 1

It turns out I need to stringify the array before stringifying it within the ajax data:

var arr = ["test","test1","test2"];
arr = JSON.stringify(arr);
$.ajax('http://mordor.fmr.com:8030/techtest?id=80a2c727de877ac9' , {
      type: "PUT",
      contentType: "application/json",
      data: JSON.stringify({
        assignedTechs: arr
      }),
      success: function() {
        // Do something
      }, 
      error: function(xhr) {
        console.log(xhr.responseText);
      }
    });