# Serving Dynamic HTML via API Gateway Example
This example illustrates how to hookup an API Gateway endpoint to a Lambda function to render HTML on a `GET` request.
## Use-cases
- Landing pages for marketing activities
- Single use dynamic webpages
## How it works
Instead of returning the default `json` from a request, you can display custom dynamic HTML by setting the `Content-Type` header to `text/html`.
```js
const response = {
statusCode: 200,
headers: {
'Content-Type': 'text/html',
},
body: html,
};
// callback will send HTML back
callback(null, response);
```
## Deploy
In order to deploy the you endpoint simply run
```bash
serverless deploy
```
The expected result should be similar to:
```bash
Serverless: Creating Stack...
Serverless: Checking Stack create progress...
.....
Serverless: Stack create finished...
Serverless: Packaging service...
Serverless: Uploading CloudFormation file to S3...
Serverless: Uploading service .zip file to S3 (1.01 KB)...
Serverless: Updating Stack...
Serverless: Checking Stack update progress...
...........................
Serverless: Stack update finished...
Service Information
service: serve-dynamic-html-via-http-endpoint
stage: dev
region: us-east-1
api keys:
None
endpoints:
GET - https://nzkl1kas89.execute-api.us-east-1.amazonaws.com/dev/landing-page
functions:
serve-dynamic-html-via-http-endpoint-dev-landingPage: arn:aws:lambda:us-east-1:377024778620:function:serve-dynamic-html-via-http-endpoint-dev-landingPage
```
## Usage
You can now send an HTTP request directly to the endpoint using a tool like curl
```bash
curl https://nzkl1kas89.execute-api.us-east-1.amazonaws.com/dev/landing-page?name=Nik%20Graf
```
The expected result should be similar to:
```bash
Landing Page
Hey Nik Graf!
%
```
Of course you can visit the URL in your browser and this is how it should look like:
To greet a specific person provide attach the query parameter with the name of that person e.g. `?name=Nik%20Graf`. The response should now contain the provided name:
## Scaling
By default, AWS Lambda limits the total concurrent executions across all functions within a given region to 100. The default limit is a safety limit that protects you from costs due to potential runaway or recursive functions during initial development and testing. To increase this limit above the default, follow the steps in [To request a limit increase for concurrent executions](http://docs.aws.amazon.com/lambda/latest/dg/concurrent-executions.html#increase-concurrent-executions-limit).