Working with annotations

Note: Annotations were previously referred to as Elements.

References have been updated in the app and documentation, while naming in the REST API and JS SDK remains unchanged.

Annotations live at the top layer of a map, and are created directly inside the Felt app.

Combining annotations with webhooks is a great way to create interactive data apps in Felt.

Listing all annotations on a map

Annotations live at the top layer of a map, and are created directly inside the Felt app.

Annotations are returned as a GeoJSON Feature Collection.

# Your API token and map ID should look like this:
# FELT_API_TOKEN="felt_pat_ABCDEFUDQPAGGNBmX40YNhkCRvvLI3f8/BCwD/g8"
# MAP_ID="CjU1CMJPTAGofjOK3ICf1D"
FELT_API_TOKEN="<YOUR_API_TOKEN>"
MAP_ID="<YOUR_MAP_ID>"

curl -L \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements"

import requests

# Your API token and map ID should look like this:
# api_token = "felt_pat_ABCDEFUDQPAGGNBmX40YNhkCRvvLI3f8/BCwD/g8"
api_token = "<YOUR_API_TOKEN>"
map_id = "<YOUR_MAP_ID>"

r = requests.get(
  f"http://felt.com/api/v2/maps/{map_id}/elements",
  headers={"Authorization": f"Bearer {api_token}"}
)
assert r.ok
print(r.json())

import os

from felt_python import list_elements

# Setting your API token as an env variable can save
# you from repeating it in every function call
os.environ["FELT_API_TOKEN"] = "<YOUR_API_TOKEN>"

map_id = "<YOUR_MAP_ID>"

list_elements(map_id)

Listing all annotation groups

Returns a list of GeoJSON Feature Collections, one for each annotation group.

curl -L \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/element_groups"

Create or update new annotations

Each annotation is represented by a feature in the POSTed GeoJSON Feature Collection.

For each feature, including an existing annotation ID (felt:id) will result in the annotation being updated on the map. If no annotation ID is provided (or a non-existent one) , a new annotation will be created.

curl -L \
  -X POST \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements" \
  -d '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{},"geometry":{"coordinates":[[[15.478752514432728,15.576176978045694],[15.478752514432728,4.005934587045303],[29.892174099255755,4.005934587045303],[29.892174099255755,15.576176978045694],[15.478752514432728,15.576176978045694]]],"type":"Polygon"}}]}'

new_elements = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "coordinates": [
          [
            [
              15.478752514432728,
              15.576176978045694
            ],
            [
              15.478752514432728,
              4.005934587045303
            ],
            [
              29.892174099255755,
              4.005934587045303
            ],
            [
              29.892174099255755,
              15.576176978045694
            ],
            [
              15.478752514432728,
              15.576176978045694
            ]
          ]
        ],
        "type": "Polygon"
      }
    }
  ]
}

r = requests.post(
  f"http://felt.com/api/v2/maps/{map_id}/elements",
  headers={"Authorization": f"Bearer {api_token}"},
  json=new_elements
)
assert r.ok
print(r.json())

from felt_python import upsert_elements

new_elements = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "coordinates": [
          [
            [
              15.478752514432728,
              15.576176978045694
            ],
            [
              15.478752514432728,
              4.005934587045303
            ],
            [
              29.892174099255755,
              4.005934587045303
            ],
            [
              29.892174099255755,
              15.576176978045694
            ],
            [
              15.478752514432728,
              15.576176978045694
            ]
          ]
        ],
        "type": "Polygon"
      }
    }
  ]
}

upsert_elements(map_id, new_elements)

Delete an annotation

Annotations can be deleted by referencing them by ID

curl -L \
  -X DELETE \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements/{ELEMENT_ID}"

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Last updated 2 days ago

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