Handling an API

🔗 Handling an API

At this point, we’ve set up some data structures around our feature, including some endpoints and params we can interact with. To handle the endpoint from the API context, we’ll make a new file /api/src/handlers/todo.ts. Just like we did with our core type folder definitions, we’ll import our new API handler file into /api/src/handlers/index.ts. Add this file reference to createHandlers, which is a simple utility function to merge all of our endpoint definitions into an object which is bound to the endpoint definitions we’re exporting from the core types folder.

In our handler file todo.ts, we’ll import createHandlers, to again make use of that binding, and begin crafting a new object. Intellisense will show us all the available endpoints we can define. It’s important to note that all endpoint definitions exported from the core package must be accompanied by a corresponding handler, otherwise the api package will not compile.

Using the POST method from our Todo example, the definition specifies a “task” as query argument, and we should return an “id”. To do this we’ll use a simple SQL query using the pg-promise client via props.tx since this is a MUTATION. If we were otherwise writing the handler for a QUERY, we would just use props.db.

import { createHandlers, ITodo } from 'awayto/core';

export default createHandlers({
  postTodo: async props => {
    const { id } = await props.tx.one<ITodo>(`
      INSERT INTO dbtable_schema.todos (task)
      VALUES ($1)
      RETURNING id
    `, [props.event.body.task]);

    return { id };
  },
  // Make sure to define the rest of the handlers below
});

That’s all there is to API handlers. Now our Express app is exposing the POST /api/todos endpoint. Check out the existing handlers in /api/src/handlers for examples of what can be done, as well as the API Props and Functionality guide to learn more about what’s available in the props object and its features.