MongoDB PHP Error: Warning: Undefined property: MongoDB\Driver\Manager

Question

I'm trying to use MongoDB on my local machine using the advice in this stack overflow. I'm using XAMPP on Windows 10, php version 8.01, and MongoDB extension 1.9.0.

It's a very basic script that connects to MongoDB and tries to use one of the databases.

But I am still getting this warning:

Connection to database successfully
Warning: Undefined property: MongoDB\Driver\Manager::$aws_inventories in C:\xampp\htdocs\mongo_connect.php on line 8

This is my code:

<?php
   require 'C:\xampp\htdocs\vendor\autoload.php'; // include Composer's autoloader
   $DB_CONNECTION_STRING="mongodb://localhost:27017";
   // connect to mongodb
   $m = new MongoDB\Driver\Manager( $DB_CONNECTION_STRING );
   echo "Connection to database successfully";
   // select a database
   $db = $m->aws_inventories;
?>

How can I get rid of the warning and connect to the DB correctly?

Answer 1

This example is adapted from the official doc https://www.php.net/manual/en/mongodb-driver-manager.executequery.php

<?php
require 'vendor/autoload.php';

$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");
$db = 'test_database';
$col = 'mycol';
$namespace = $db.'.'.$col;

// insert data
$bulk = new MongoDB\Driver\BulkWrite;
$bulk->insert(['x' => 1]);
$bulk->insert(['x' => 2]);
$bulk->insert(['x' => 3]);
$manager->executeBulkWrite($namespace, $bulk);

// query
$query = new MongoDB\Driver\Query(['x' => ['$gt' => 1]], []);
$cursor = $manager->executeQuery($namespace, $query);

foreach ($cursor as $document) {
    var_dump($document);
}

As the document suggests, MongoDB\Driver\Manager is a generic abstraction to manage any type of MongoDB connection (standalone server, replica set, or sharded cluster) so the methods will look a bit too complicated for simple CRUD on standalone server.

If you just want to connect to a standalone server, you may want to check MongoDB\Client. Here is the code that do exactly the same thing:

<?php
require 'vendor/autoload.php';

$client = new MongoDB\Client("mongodb://localhost:27017");
$col = $client->test_database->mycol;

// insert data
$col->insertMany([
    ['x' => 1],
    ['x' => 2],
    ['x' => 3],
]);

// query
$docs = $col->find(['x' => ['$gt' => 1]]);
foreach ($docs as $document) {
    var_dump($document);
}

Answer 2

First, you're trying to access a property which doesn't exists in MongoDB\Driver\Manager class object.

Second, $db = $m->aws_inventories; works with MongoDB\Client library.

Here are few example to get collections list or find all/specific document/s or insert/bulk insert, update a document or to perform a distinct query

Get all collections of aws_inventories:

try {
    $manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
    $command = new MongoDB\Driver\Command(["listCollections" => 1]);
    
    $cursor = $manager->executeCommand("aws_inventories", $command);
    
    // list of all collections in aws_inventories
    $collections = $cursor->toArray();
    
    var_dump($collections);
} catch (\MongoDB\Driver\Exception\Exception $e) {
}

Get all documents from a collection:

try {
    $manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
    
    // setting options and filter
    $filter  = [];
    $options = [];
    
    /*
    // or to find specific documents based on a condition and limit records
    $filter  = [
        'service' => 'ec2',
        'instance' => 'co',
        'type' => 'c5',
        'vCPU' => [
            '$gt' => 2
        ]
    ];
    
    $options = [
        'limit' => 10,
        'maxTimeMS' => 1000,    // to limit the execution time of a query
        'sort' => [
            'vCPU' => -1
        ]
    ];
    */
    
    // constructing the query
    $query = new MongoDB\Driver\Query($filter, $options);
    
    $cursor = $manager->executeQuery('aws_inventories.test', $query);
    
    foreach ($cursor as $document) {
        var_dump($document);
    }
} catch (\MongoDB\Driver\Exception\Exception $e) {
}

To perform distinct query:

try {
    $manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
    
    $query = [
        'size' => '2xlarge'
    ];
    $command = new MongoDB\Driver\Command([
        'distinct' => 'test',   // Collection name
        'key' => 'instance',    // field for which we want to get distinct values
        'query' => $query       // criteria to filter documents
    ]);
        
    $cursor = $manager->executeCommand("aws_inventories", $command);
    
    // to get distinct values as array
    $instances = current($cursor->toArray())->values;
    
    var_dump($instances);
} catch (\MongoDB\Driver\Exception\Exception $e) {
}

To insert single/multiple document/s:

try {
    $manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
    $bulk = new MongoDB\Driver\BulkWrite;

    $bulk->insert([
        'service' => 'ec2',
        'instance' => 'co',
        'type' => 'c5',
        'size' => 'large',
        'model' => 'c5.large',
        'vCPU' => 2,
        'memory' => 4,
        'storage' => 'ebs-only',
        'network_bandwidth' => 10,
        'ebs_bandwidth' => 4750  
    ]);
    
    $bulk->insert([
        'service' => 'ec2',
        'instance' => 'gp',
        'type' => 't3',
        'size' => 'nano',
        'model' => 't3.nano',
        'vCPU' => 2,
        'memory' => 0.5,
        'storage' => 'ebs-only',
        'network_bandwidth' => 5 
    ]);
    
    $result = $manager->executeBulkWrite('aws_inventories.test', $bulk);
    
} catch (\MongoDB\Driver\Exception\Exception $e) {
}

To update existing document/s: (Taken from executeUpdate example)

try {
    $manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
    $criteria = [
        'service' => 'ec2',
        'type' => 'c5'
    ];
    
    $document = [
        '$set' => [
            'features' => [
                'Powered by the AWS Nitro System, a combination of dedicated hardware and lightweight hypervisor'
            ]           
        ]       
    ];

    $updateOptions = array(
        'multi' => true,    // false - to update only first matching document, true - update all matching documents
        'upsert' => 0
    );
    
    $writeConcern = new MongoDB\Driver\WriteConcern(MongoDB\Driver\WriteConcern::MAJORITY, 100);

    $result = $manager->executeUpdate('aws_inventories.test', $criteria, $document, $updateOptions, $writeConcern);
    
    printf("Updated %d document(s)\n", $result->getModifiedCount());
    printf("Matched %d document(s)\n", $result->getMatchedCount());
    printf("Upserted documents: %d\n", $result->getUpsertedCount());
    foreach ($result->getUpsertedIds() as $index => $id) {
        printf("upsertedId[%d]: ", $index);
        var_dump($id);
    }
    
    /* If the WriteConcern could not be fulfilled */
    if ($writeConcernError = $result->getWriteConcernError()) {
        printf("%s (%d): %s\n", $error->getMessage(), $error->getCode(), var_export($error->getInfo(), true));
    }
    
    /* If the write could not happen at all */
    foreach ($result->getWriteErrors() as $writeError) {
        printf("%s (%d)\n", $error->getMessage(), $error->getCode());
    }
} catch (\MongoDB\Driver\Exception\Exception $e) {
}

Answer 3

$m->aws_inventories That looks like as the older/deprecated approach. Could you try to follow this tutorial?

https://zetcode.com/db/mongodbphp/

<?php

try {

    $mng = new MongoDB\Driver\Manager("mongodb://localhost:27017");

    $stats = new MongoDB\Driver\Command(["dbstats" => 1]);
    $res = $mng->executeCommand("aws_inventories", $stats);
    
    $stats = current($res->toArray());

    print_r($stats);

} catch (MongoDB\Driver\Exception\Exception $e) {

    $filename = basename(__FILE__);
    
    echo "The $filename script has experienced an error.\n"; 
    echo "It failed with the following exception:\n";
    
    echo "Exception:", $e->getMessage(), "\n";
    echo "In file:", $e->getFile(), "\n";
    echo "On line:", $e->getLine(), "\n";       
}
    
?>