Add a List All the Notes API
Now we are going to add an API that returns a list of all the notes a user has.
Add the Function
Create a new file called list.js
with the following.
import handler from "./libs/handler-lib";
import dynamoDb from "./libs/dynamodb-lib";
export const main = handler(async (event, context) => {
const params = {
TableName: process.env.tableName,
// 'KeyConditionExpression' defines the condition for the query
// - 'userId = :userId': only return items with matching 'userId'
// partition key
KeyConditionExpression: "userId = :userId",
// 'ExpressionAttributeValues' defines the value in the condition
// - ':userId': defines 'userId' to be the id of the author
ExpressionAttributeValues: {
":userId": "123",
},
};
const result = await dynamoDb.query(params);
// Return the matching list of items in response body
return result.Items;
});
This is pretty much the same as our get.js
except we use a condition to only return the items that have the same userId
as the one we are passing in. In our case, it’s still hardcoded to 123
.
Configure the API Endpoint
Open the serverless.yml
file and append the following.
list:
# Defines an HTTP API endpoint that calls the main function in list.js
# - path: url path is /notes
# - method: GET request
handler: list.main
events:
- http:
path: notes
cors: true
method: get
This defines the /notes
endpoint that takes a GET request.
Test
Create a mocks/list-event.json
file and add the following.
{}
We are still adding an empty mock event because we are going to replace this later on in the guide.
And invoke our function from the root directory of the project.
$ serverless invoke local --function list --path mocks/list-event.json
The response should look similar to this.
{
"statusCode": 200,
"body": "[{\"attachment\":\"hello.jpg\",\"content\":\"hello world\",\"createdAt\":1602891322039,\"noteId\":\"42244c70-1008-11eb-8be9-4b88616c4b39\",\"userId\":\"123\"}]"
}
Note that this API returns an array of note objects as opposed to the get.js
function that returns just a single note object.
Next we are going to add an API to update a note.
For help and discussion
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