Javascript – Bootstrap Typeahead with AJAX source: not returning array as expected

ajaxbootstrap-typeaheadjavascriptjquerytwitter-bootstrap

I am having a lot of trouble getting bootstraps typeahead to work properly with an AJAX source.

If I alert out the array that is being returned it is perfectly fine, even when I hard code it to test it. It seems to return nothing most of the time or only a few items from the array when you have typed in a near match.

Here is what I have at the moment:

$('#companyNameInput').typeahead({
      source: function(query, process){

          $.ajax({
            url: ROOT+'Record/checkCompanyName',
            async: false,
            data: 'q='+query,
            type: 'POST',
            cache: false,
            success: function(data)
            {
              companiesFinal = [];
              map = {};
              companies = $.parseJSON(data);
              $.each(companies, function(i, v){
                map[v.name] = v.id;
                companiesFinal.push(v.name);
              })
            }
          })
          process(companiesFinal);

          // return ['test1', 'test2'] This works fine
          return companiesFinal;
      }

Does anyone have an idea why this is working properly?

Here is an example of the object array returned from my PHP script. Objects with IDs 1 and 1216 show up on the typeahead dropdown, but non of the others do. I can not see any patterns or clue as to why only these would show and not the others.

[
   {
      "id": "1265",
      "score": "40",
      "name": "LMV AB"
   },
   {
      "id": "10834",
      "score": "33",
      "name": "Letona"
   },
   {
      "id": "19401",
      "score": "33",
      "name": "Lewmar"
   },
   {
      "id": "7158",
      "score": "33",
      "name": "Lazersan"
   },
   {
      "id": "3364",
      "score": "33",
      "name": "Linpac"
   },
   {
      "id": "1216",
      "score": "33",
      "name": "L H Evans Limted"
   },
   {
      "id": "1",
      "score": "33",
      "name": "LH Evans Ltd"
   },
   {
      "id": "7157",
      "score": "33",
      "name": "Lazersan"
   }
]

And finally the array that is past in process(companiesFinal):

["LMV AB", "Letona", "Lewmar", "Lazersan", "Linpac", "L H Evans Limted", "LH Evans Ltd", "Lazersan"]

Anyone have any clue? I am still totally clueless as to why this isn't working still 🙁

$('#companyNameInput').typeahead({
      source: function(query, process){

        companyTOut = setTimeout(function(){
          return $.ajax({
            url: ROOT+'Record/checkCompanyName',
            data: 'q='+query,
            type: 'POST',
            dataType: 'json',
            cache: false,
            success: function(data)
            {
              var count = 0;
              var companiesFinal = [];
              map = [];
              $.each(data, function(i, v){
                map[v.name] = [v.id, v.score];
                companiesFinal.push(v.name);
              })
              process(companiesFinal);

            }
          })
        }, 250)
      },
      minLength: 2,
      highlighter: function(item)
      {
        $('#companyNameInput').closest('.control-group').removeClass('success')
        companyLocked = false;
        return '<span class="unselectable" title="'+map[item].score+'">'+item+'</span>';
      },
      updater: function(item)
      {
        selectedEntityId = map[item][0];
        selectedCountryScore = map[item][1];
        lockCompany(selectedEntityId);
        return item;
      }
    });

$output .= '['.$output;
    foreach($results as $result) {
      $output .= '{"id":"'.$result['id'].'",';
      $output .= '"score":"'.$result['score'].'",';
      $output .= '"name":'.json_encode($result['name']).'},';
    }
    header('Content-Type: application/json');
    echo substr($output, 0, strlen($output)-1).']';

Console output for "parm":

[Object, Object, Object, Object, Object, Object]
0: Object
id: "25024"
name: "part"
score: "75"
__proto__: Object
1: Object
id: "15693"
name: "pari"
score: "75"
__proto__: Object
2: Object
id: "28079"
name: "Pato"
score: "50"
__proto__: Object
3: Object
id: "18001"
name: "PASS"
score: "50"
__proto__: Object
4: Object
id: "15095"
name: "PSR"
score: "33"
__proto__: Object
5: Object
id: "22662"
name: "PRP"
score: "33"
__proto__: Object
length: 6
__proto__: Array[0]

Best Answer

Update 2

Ah, your service returns items that actually don't match the query parm. Your typeahead query is 'parm', with which none of the returned results match. You can override the matcher function used by the typeahead plugin, see the docs. Simply implement it as return true to match all results returned by your service.

Update 1

This is an updated version, that maps the name to an id, which can be used later. A jsfiddle is available.

var nameIdMap = {};

$('#lookup').typeahead({
    source: function (query, process) {
        return $.ajax({
            dataType: "json",
            url: lookupUrl,
            data: getAjaxRequestData(),
            type: 'POST',
            success: function (json) {
                process(getOptionsFromJson(json));
            }
        });
    },
    minLength: 1,
    updater: function (item) {
        console.log('selected id'+nameIdMap[item]);
        return item;
    }
});

function getOptionsFromJson(json) {
    $.each(json, function (i, v) {
        nameIdMap[v.name] = v.id;
    });

    return $.map(json, function (n, i) {
        return n.name;
    });
}

Original answer

You need to make the call async and call the process callback from within the success callback like this:

$('#companyNameInput').typeahead({
    source: function (query, process) {
        $.ajax({
            url: ROOT + 'Record/checkCompanyName',
            // async: false, // better go async
            data: 'q=' + query,
            type: 'POST',
            cache: false,
            success: function (data) {
                var companiesFinal = ... // snip
                process(companiesFinal);
            }
        })
    }
});

The return ['test1', 'test2']; works, because the source function is then basically set to:

// do ajax stuff, but do nothing with the result
// return the typeahead array, which the typeahead will accept as the result:
return ['test1', 'test2'];

Notes

There is a one-liner to fill companiesData:

var companiesFinal = return $.map(data, function (n, i) { n.name; });

And you probably want to declare your variables using var; otherwise they'll have global scope, which will bite you.

Related Solutions

Javascript – How to extend an existing JavaScript array with another array, without creating a new array

The .push method can take multiple arguments. You can use the spread operator to pass all the elements of the second array as arguments to .push:

>>> a.push(...b)

If your browser does not support ECMAScript 6, you can use .apply instead:

>>> a.push.apply(a, b)

Or perhaps, if you think it's clearer:

>>> Array.prototype.push.apply(a,b)

Please note that all these solutions will fail with a stack overflow error if array b is too long (trouble starts at about 100,000 elements, depending on the browser).
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Javascript – jQuery Ajax POST example with PHP

Basic usage of .ajax would look something like this:

HTML:

<form id="foo">
    <label for="bar">A bar</label>
    <input id="bar" name="bar" type="text" value="" />

    <input type="submit" value="Send" />
</form>

jQuery:

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    // Callback handler that will be called on failure
    request.fail(function (jqXHR, textStatus, errorThrown){
        // Log the error to the console
        console.error(
            "The following error occurred: "+
            textStatus, errorThrown
        );
    });

    // Callback handler that will be called regardless
    // if the request failed or succeeded
    request.always(function () {
        // Reenable the inputs
        $inputs.prop("disabled", false);
    });

});

Note: Since jQuery 1.8, .success(), .error() and .complete() are deprecated in favor of .done(), .fail() and .always().

Note: Remember that the above snippet has to be done after DOM ready, so you should put it inside a $(document).ready() handler (or use the $() shorthand).

Tip: You can chain the callback handlers like this: $.ajax().done().fail().always();

PHP (that is, form.php):

// You can access the values posted by jQuery.ajax
// through the global variable $_POST, like this:
$bar = isset($_POST['bar']) ? $_POST['bar'] : null;

Note: Always sanitize posted data, to prevent injections and other malicious code.

You could also use the shorthand .post in place of .ajax in the above JavaScript code:

$.post('/form.php', serializedData, function(response) {
    // Log the response to the console
    console.log("Response: "+response);
});

Note: The above JavaScript code is made to work with jQuery 1.8 and later, but it should work with previous versions down to jQuery 1.5.