mikelehen

/**
 * Fancy ID generator that creates 20-character string identifiers with the following properties:
 *
 * 1. They're based on timestamp so that they sort *after* any existing ids.
 * 2. They contain 72-bits of random data after the timestamp so that IDs won't collide with other clients' IDs.
 * 3. They sort *lexicographically* (so the timestamp is converted to characters that will sort properly).
 * 4. They're monotonically increasing.  Even if you generate more than one in the same timestamp, the
 *    latter ones will sort after the former ones.  We do this by using the previous random bits
 *    but "incrementing" them by 1 (only in the case of a timestamp collision).
 */

mikelehen

POST https://firestore.googleapis.com/v1beta1/projects/firestore-fun/databases/(default)/documents:commit?key={YOUR_API_KEY}
 
{
 "writes": [
  {
   "update": {
    "name": "projects/firestore-fun/databases/(default)/documents/foo/bar",
    "fields": {
     "some-field": {
      "stringValue": "some-value"