Demonstrate creating cards (simply), finding them again (using filtered select), and then modifying them using the Supernotes API.

supernotesApiExample.js

// please note that this script contains limited error / success checking, 
// and a production script should probably have more (e.g. checking the 
// status of requests before you try to do things with the data)

const baseUrl = 'https://api.supernotes.app/v1'
const apiKey = 'MY_API_KEY'

const headers = new Headers({
  'Api-Key': apiKey,
  'Content-Type': 'application/json',
})

const MY_SPECIAL_TAG = 'special tag'

// create two cards with `MY_SPECIAL_TAG` tags, don't bother storing IDs for now
// create first card
await fetch(`${baseUrl}/cards/simple`, {
  headers,
  method: 'POST',
  body: JSON.stringify({
    name: 'First card',
    markup: 'Some **markdown** content.',
    tags: [MY_SPECIAL_TAG],
  }),
})
// make second card
await fetch(`${baseUrl}/cards/simple`, {
  headers,
  method: 'POST',
  body: JSON.stringify({
    name: 'Second card',
    markup: 'More markdown !!content!!.',
    tags: [MY_SPECIAL_TAG],
  }),
})

// now get all cards with my tag
const filteredSelect = {
    filter_group: {
      operator: 'and',
      filters: [
        {
          type: 'tag',
          operator: 'contains',
          arg: MY_SPECIAL_TAG,
        },
      ],
    }
}
const response = await fetch(`${baseUrl}/cards/get/select`, {
  headers,
  method: 'POST',
  body: JSON.stringify(filteredSelect),
})
const foundCardIds = Object.keys(await response.json());

// send a request to change all these cards to have a different tag set
const ADDITIONAL_TAG = "second"
const modificationPayload = {};
foundCardIds.forEach(cardId => {
  modificationPayload[cardId] = { data: { tags: [MY_SPECIAL_TAG, ADDITIONAL_TAG] } }
})
await fetch(`${baseUrl}/cards/`, {
  headers,
  method: 'PATCH',
  body: JSON.stringify(modificationPayload),
})

// get the count of cards with the second tag to ensure we did everything right
const filteredSelect2 = {
    filter_group: {
      operator: 'and',
      filters: [
        {
          type: 'tag',
          operator: 'contains',
          arg: ADDITIONAL_TAG,
        },
      ],
    }
}
const response2 = await fetch(`${baseUrl}/cards/get/select`, {
  headers,
  method: 'POST',
  body: JSON.stringify(filteredSelect2),
})

if (response.ok) {
  console.log(Object.keys(await response2.json()).length)
  // should be `2`
}