Connect from AWS Lambda
Learn how to set up a Neon database and connect from an AWS Lambda function
AWS Lambda is a serverless, event-driven compute service that allows you to run code without provisioning or managing servers. It is a convenient and cost-effective solution for running various types of workloads, including those that require a database.
This guide describes how to set up a Neon database and connect to it from an AWS Lambda function using Node.js as the runtime environment. It covers:
- Creating a Lambda function using the Serverless Framework, which is a serverless application lifecycle management framework.
- Connecting your Lambda function to a Neon database.
- Deploying the Lambda function to AWS.
- A Neon account. If you do not have one, see Sign up for instructions.
- An AWS account. You can create a free AWS account at AWS Free Tier. An IAM User and Access Key are required to programmatically interact with your AWS account. You must provide these credentials when deploying the Serverless Framework project.
- A Service Framework account. You can sign up at Serverless Framework.
Create a Neon project
If you do not have one already, create a Neon project:
- Navigate to the Projects page in the Neon Console.
- Click New Project.
- Specify your project settings and click Create Project.
Create a table in Neon
To create a table, navigate to the SQL Editor in the Neon Console:
In the SQL Editor, run the following queries to create a
users table and insert some data:
Create a Lambda function
Create the Lambda function using the Serverless Framework:
Install the Serverless Framework by running the following command:
my-lambdaproject directory and navigate to it.
Run the serverless command to create a serverless project.
Follow the prompts, as demonstrated below. You will be required to provide your AWS account credentials. The process creates an
Navigate to the
aws-node-projectdirectory created by the previous step and install the
node-postgrespackage, which you will use to connect to the database.
After installing the
node-postgrespackage, the following dependency should be defined in your
aws-node-projectdirectory, add a
users.jsfile, and add the following code to it:
The code in the
users.jsfile exports the
getAllUsersfunction, which retrieves all rows from the
userstable and returns them as a
JSONobject in the
This function uses the
pglibrary to connect to the Neon database. It creates a new
Clientinstance and passes the database connection string, which is defined in the
DATABASE_URLenvironment variable. It then calls
connect()to establish a connection to the database. Finally, it uses the
query()method to execute a
SELECTstatement that retrieves all rows from the
The query method returns a
Promisethat resolves to an object containing the rows retrieved by the
SELECTstatement, which the function parses to retrieve the
rowsproperty. Finally, the function returns an
HTTPresponse with a status code of 200 and a body that contains a
JSONobject with a single
dataproperty, which is set to the value of the rows variable.
DATABASE_URLenvironment variable and the function definition to the
serverless.ymlfile, which is located in your
You can copy the connection string from Connection Details widget the Neon Console. Add the
environment, and add
sslmode=requireto the end of the connection string to enable SSL. The
sslmode=requireoption tells Postgres to use SSL encryption and verify the server's certificate.
Deploy the serverless function using the following command:
serverless deploycommand generates an API endpoint using API Gateway. The output of the command appears similar to the following:
Test the generated endpoint by running a cURL command. For example:
The response returns the following data:
If you make API calls to the Lambda function from your app, you will likely need to configure Cross-Origin Resource Sharing (CORS). Visit the AWS documentation for information about how to enable CORS in API Gateway.
You can run the following command to enable CORS to your local development environment:
You can find your
api-id on the API Gateway dashboard:
In this guide, you have learned how to set up a Postgres database using Neon and connect to it from an AWS Lambda function using Node.js as the runtime environment. You have also learned how to use Serverless Framework to create and deploy the Lambda function, and how to use the
pg library to perform a basic database read operations.