Yet another mongodb native driver facade. Takes care of:
- mongo URI parsing
- opening and closing DB connections
- opening collections
Install by running
npm install mniam
Connect to database mniam-test
and create friends
collection with index on name
field.
const db = database('mongodb://localhost/mniam-test');
const friends = db.collection({
name: 'friends',
indexes: [[{ name: 1 }]]
});
Mniam is using MongoClient to establish the connection: full mongo database URLs are supported. The database function also takes a hash of options divided into db/server/replset/mongos allowing you to tweak options not directly supported by the unified url string format.
const db = database('mongodb://localhost/mniam-test', {
db: {
w: -1
},
server: {
ssl: true
}
});
Add a new documents:
const item = await friends.save({
name: 'Alice',
age: 14,
};
console.log('Item id:', item._id);
Update a document:
const item = await friends.findAndModify({ _id: item._id }, {
$set: { age: 15 }
});
console.log('Alice is now:', item.age);
Remove a document:
await friends.deleteOne({ name: 'Alice' });
Use query
, fields
and options
to create and configure cursor.
Iterate over the results of the query using toArray
, eachSeries
, eachLimit
methods.
items
- can be used as async iterator
for await (const friend of friends.query({ age: { $gt: 21 } }).items()) {
console.log('My friend over 21 years old', friend.name);
}
toArray
- converts query results into array
const arr = await friends.query({ age: { $gt: 21 } }).toArray();
console.log('My friends over 21 years old', arr);
eachSeries
- callsonItem
sequentially for all results
await friends
.query()
.fields({ name: 1 })
.eachSeries(async item => console.log('Name:', item.name));
console.log('All friends listed.');
eachLimit
- iterates over all results callingonItem
in parallel, but no more thanlimit
at a time
await friends
.query()
.options({ sort: { age: 1 } })
.eachLimit(4, async item => console.log('Friend', item));
console.log('All friends listed.');
Mniam collections provides flex API for aggregation pipeline:
const results = await friends
.aggregate() // start pipeline
.project({ author: 1, tags: 1 })
.unwind('$tags')
.group({
_id : { tags : '$tags' },
authors : { $addToSet : '$author' },
count: { $sum: 1 }
})
.sort({ count: -1 })
.toArray();
console.log(results);
In addition to toArray
you can use eachSeries
and eachLimit
to iterate over aggregation results.
Each aggregation stage ($project
, $unwind
, $sort
, etc.) has a corresponding function with the same
name (without $
). You can also pass a traditional array of stages to .pipeline(stages)
method, and set
options with .options({})
method.
MIT