Documentation for .group

[nilportugues]

Hello.

I managed to code a full library using this library (https://github.com/nilportugues/php-mongodb-repository)... but I haven't managed to do get this running:

db.book_facets.group({
    "key": {
        "facetName": true,
        "facetValue": true
    },
    "initial": {
        "total": 0
    },
    "reduce": function(obj, prev) {
        if (obj.facetValue != null) if (obj.facetValue instanceof Array) prev.total += obj.facetValue.length;
        else prev.total++;
    }
});

Any clues or better documentation on how to run this?
Thanks

[derickr]

I'm not sure whether you found the right github repository. Your code example is in javascript? This is the repository for the PHP library...

[nilportugues]

Hey @derickr thanks for the reply!

Thing is I'm trying to do this in PHP, and I wrote that repository, but I'm clueless on how to do this after examining this library's API.

[jmikola]

@nilportugues: The PHP library doesn't include a wrapper for the group command, so at present you'll need to use the Database::command() method directly by executing a command document:

$database = (new MongoDB\Client)->selectDatabase('test');
$cursor = $database->command([
    'group' => [
        'ns' => 'book_facets',
        'key' => ['facetName' => true, 'facetValue' => true],
        'initial' => ['total' => 0],
        '$reduce' => new MongoDB\BSON\Javascript('...'),
    ],
]);

$resultDocument = $cursor->toArray()[0];

I've opened PHPLIB-177 to track the request and linked it to a pre-existing ticket we have to also create a mapReduce helper in 1.1.0. While we definitely plan to add mapReduce, we were on the fence with group as it's generally discouraged in favor of the aggregation pipeline and mapReduce. In any event, that should be the ticket to watch for any future API changes.

[nilportugues]

@jmikola @derickr thanks 👍