How to Deploy MongoDB with Marketplace Apps

MongoDB is a database engine that provides access to non-relational, document-oriented databases. It is part of the growing NoSQL movement, along with databases like Redis and Cassandra (although there are vast differences among the many non-relational databases).

MongoDB seeks to provide an alternative to traditional relational database management systems (RDBMS). In addition to its schema-free design and scalable architecture, MongoDB provides a JSON output and specialized, language-specific bindings that make it particularly attractive for use in custom application development and rapid prototyping. MongoDB has been used in a number of large scale production deployments and is currently one of the most popular database engines across all systems.

Deploying the MongoDB Marketplace App

The Linode Marketplace allows you to easily deploy software on a Linode using the Linode Cloud Manager.

1. Log in to the Cloud Manager and select the Marketplace link from the left navigation menu. This displays the Linode Compute Create page with the Marketplace tab pre-selected.

2. Under the Select App section, select the app you would like to deploy.

3. Fill out all required Options for the selected app as well as any desired Advanced Options (which are optional). See the Configuration Options section for details.

4. Complete the rest of the form as discussed within the Getting Started > Create a Linode.

5. Click the Create Linode button. Once the Linode has provisioned and has fully powered on, wait for the software installation to complete. If the Linode is powered off or restarted before this time, the software installation will likely fail. To determine if the installation has completed, open the Linode’s Lish console and wait for the system login prompt to appear.

6. Follow the instructions within the Getting Started After Deployment section.

Software installation should complete within 2-5 minutes after the Linode has finished provisioning.

Configuration Options

MongoDB Options

Here are the additional options available for this Marketplace App:

• Mongo password (required): Password for your MongoDB admin account.

General Options

For advice on filling out the remaining options on the Create a Linode form, see Getting Started > Create a Linode. That said, some options may be limited or recommended based on this Marketplace App:

• Supported distributions: Debian 9
• Recommended minimum plan: All plan types and sizes can be used, though consider using a High Memory Compute Instance for larger databases in a production environment.

Getting Started after Deployment

Access MongoDB

After MongoDB has finished installing, you will be able to access MongoDB from the console via ssh with your Linode’s IPv4 address:

1. SSH into your Linode and create a limited user account.

2. Log out and log back in as your limited user account.

3. Update your server:

   sudo apt-get update && apt-get upgrade
   

4. Access MongoDB with the admin account password you set when launching the Marketplace App:

   mongo -u admin -p --authenticationDatabase admin
   

   The -u, -p, and --authenticationDatabase options in the above command are required in order to authenticate connections to the shell. Without authentication, the MongoDB shell can be accessed but will not allow connections to databases.

   The admin user is purely administrative based on the roles specified. It is defined as an administrator of users for all databases, but does not have any database permissions itself. You may use it to create additional users and define their roles. If you are using multiple applications with MongoDB, set up different users with custom permissions for their corresponding databases.

5. As the admin user, create a new database to store regular user data for authentication. The following example calls this database user-data:

   use user-data
   

6. Permissions for different databases are handled in separate roles objects. This example creates the user, example-user, with read-only permissions for the user-data database and has read and write permissions for the exampleDB database that we’ll create in the Manage Data and Collections section below.

   Create a new, non-administrative user to enter test data. Change both example-user and password to something relevant and secure:

   db.createUser({user: "example-user", pwd: "password", roles:[{role: "read", db: "user-data"}, {role:"readWrite", db: "exampleDB"}]})
   

   To create additional users, repeat this step as the administrative user, creating new usernames, passwords and roles by substituting the appropriate values.

7. Exit the mongo shell:

   quit()
   

For more information on access control and user management, as well as other tips on securing your databases, refer to the MongoDB Security Documentation.

Manage Data and Collections

Much of MongoDB’s popularity comes from its ease of integration. Interactions with databases are done via JavaScript methods, but drivers for other languages are available. This section will demonstrate a few basic features, but we encourage you to do further research based on your specific use case.

1. Open the MongoDB shell using the example-user we created above:

   mongo -u example-user -p --authenticationDatabase user-data
   

2. Create a new database. This example calls it exampleDB:

   use exampleDB
   

   Make sure that this database name corresponds with the one for which the user has read and write permissions (we added these permissions in the previous section).

   To show the name of the current working database, run the db command.

3. Create a new collection called exampleCollection:

   db.createCollection("exampleCollection", {capped: false})
   

   If you’re not familiar with MongoDB terminology, you can think of a collection as analogous to a table in a relational database management system. For more information on creating new collections, see the MongoDB documentation on the db.createCollection() method.

   Note

   Collection names should not include certain punctuation such as hyphens. However, exceptions may not be raised until you attempt to use or modify the collection. For more information, refer to MongoDB’s naming restrictions.

4. Create sample data for entry into the test database. MongoDB accepts input as documents in the form of JSON objects such as those below. The a and b variables are used to simplify entry; objects can be inserted directly via functions as well.

   var a = { name : "John Doe",  attributes: { age : 30, address : "123 Main St", phone : 8675309 }}
   var b = { name : "Jane Doe",  attributes: { age : 29, address : "321 Main Rd", favorites : { food : "Spaghetti", animal : "Dog" } }}
   

   Note that documents inserted into a collection need not have the same schema, which is one of many benefits of using a NoSQL database.

5. Insert the data into exampleCollection, using the insert method:

   db.exampleCollection.insert(a)
   db.exampleCollection.insert(b)
   

   The output for each of these operations will show the number of objects successfully written to the current working database:

   WriteResult({ "nInserted" : 1 })

6. Confirm that the exampleCollection collection was properly created:

   show collections
   

   The output will list all collections containing data within the current working database:

   exampleCollection

7. View unfiltered data in the exampleCollection collection using the find method. This returns up to the first 20 documents in a collection, if a query is not passed:

   db.exampleCollection.find()
   

   The output will resemble the following:

   { "_id" : ObjectId("5e68d4618bd4ea23cc3f5e96"), "name" : "John Doe", "attributes" : { "age" : 30, "address" : "123 Main St", "phone" : 8675309 } }
   { "_id" : ObjectId("5e68d4628bd4ea23cc3f5e97"), "name" : "Jane Doe", "attributes" : { "age" : 29, "address" : "321 Main Rd", "favorites" : { "food" : "Spaghetti", "animal" : "Dog" } } }

   You may notice the objects we entered are preceded by _id keys and ObjectId values. These are unique indexes generated by MongoDB when an _id value is not explicitly defined. ObjectId values can be used as primary keys when entering queries, although for ease of use, you may wish to create your own index as you would with any other database system.

   The find method can also be used to search for a specific document or field by entering a search term parameter (in the form of an object) rather than leaving it empty. For example:

   db.exampleCollection.find({"name" : "John Doe"})
   

   Running the command above returns a list of documents containing the {"name" : "John Doe"} object:

   { "_id" : ObjectId("5e68d4618bd4ea23cc3f5e96"), "name" : "John Doe", "attributes" : { "age" : 30, "address" : "123 Main St", "phone" : 8675309 } }

Next Steps

Note

Currently, Linode does not manage software and systems updates for Marketplace Apps. It is up to the user to perform routine maintenance on software deployed in this fashion.

For more on MongoDB, checkout the following guides:

• Creating a MongoDB Replica Set
• Building Database Clusters with MongoDB

More Information

You may wish to consult the following resources for additional information on this topic. While these are provided in the hope that they will be useful, please note that we cannot vouch for the accuracy or timeliness of externally hosted materials.

• Official MongoDB Documentation
• MongoDB Project
• Language-Specific MongoDB Drivers