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The @lark-sh/client package exports several utility functions and constants for working with paths, IDs, and server values. 
import {
  generatePushId,
  ServerValue,
  normalizePath,
  joinPath,
  getParentPath,
  getKey,
  isVolatilePath,
} from '@lark-sh/client';

​
generatePushId

generatePushId(): string
Generates a unique, chronologically-sortable 20-character ID. The format is identical to the keys produced by DatabaseReference.push(). IDs are ordered by time, so items created earlier sort before items created later when using orderByKey(). 
const id = generatePushId();
// e.g. "-NxK3jR2fHa0YkLm9pQr"

await db.ref(`posts/${id}`).set({
  title: 'My Post',
  createdAt: ServerValue.TIMESTAMP,
});
Use generatePushId() when you need a key before writing, such as when referencing the key in multiple locations within a single update() call.

​
ServerValue.TIMESTAMP

ServerValue.TIMESTAMP: object
A placeholder value that the server replaces with its current timestamp (milliseconds since the Unix epoch) at the time the write is committed. Use this instead of Date.now() to ensure consistency across clients with different clock offsets. 
await db.ref('users/alice').update({
  lastLogin: ServerValue.TIMESTAMP,
});
ServerValue.TIMESTAMP is a sentinel object, not an actual number. It is resolved server-side when the write is processed.

​
normalizePath

normalizePath(path: string): string
Normalizes a database path by removing double slashes, trailing slashes, and leading slashes.
ParameterTypeDescription
pathstringThe path to normalize.
normalizePath('//users//alice/');
// "users/alice"

normalizePath('/');
// ""

​
joinPath

joinPath(...segments: string[]): string
Joins one or more path segments with /, producing a normalized path.
ParameterTypeDescription
...segmentsstring[]Path segments to join.
joinPath('users', 'alice', 'profile');
// "users/alice/profile"

joinPath('rooms', 'room1', 'members');
// "rooms/room1/members"

​
getParentPath

getParentPath(path: string): string
Returns the parent path of the given path. Returns an empty string for top-level paths.
ParameterTypeDescription
pathstringThe path to get the parent of.
getParentPath('users/alice/profile');
// "users/alice"

getParentPath('users');
// ""

​
getKey

getKey(path: string): string
Returns the last segment of a path (the key).
ParameterTypeDescription
pathstringThe path to extract the key from.
getKey('users/alice/profile');
// "profile"

getKey('users');
// "users"

​
isVolatilePath

isVolatilePath(path: string, patterns: string[]): boolean
Checks whether a given path matches any of the provided volatile path patterns. Volatile paths are used for high-frequency, low-latency data streams such as cursor positions or live indicators.
ParameterTypeDescription
pathstringThe path to check.
patternsstring[]An array of volatile path patterns to match against. Patterns support * as a single-segment wildcard.
const patterns = ['cursors/*', 'typing/*'];

isVolatilePath('cursors/alice', patterns);
// true

isVolatilePath('users/alice', patterns);
// false