Custom API

Rill allows you to create custom APIs to pull data out in a flexible manner. You can write custom SQL queries and expose them as an API endpoint.

Create a custom API

To create a custom API, create a new yaml file under apis directory in your Rill project. Currently, we support two types of custom APIs:

SQL API: You can write a SQL query and expose it as an API endpoint. This is useful when you want to directly write queries against a model that you have created. It should have the following structure:
```
kind: api
sql: SELECT abc FROM my_table
```
where my_table is your model name. Read more details about SQL apis.
Metrics SQL API: You can write a SQL query referring to metrics definition and dimensions defined in the metrics view. It should have the following structure:
```
kind: api
metrics_sql: SELECT dimension, AGGREGATE(measure) FROM my_metrics GROUP BY dimension
```
where my_metrics is your metrics view name, measure is a custom metrics that you have defined. Read more details about Metrics SQL API.

Refer to the integration docs here to learn how to use custom APIs in your application.