Config Methods

getConfig()

Get configuration value synchronously from cache or defaults.

grain.getConfig(key: string): string | undefined

Parameters:

key - Configuration key

Returns: Configuration value or undefined Example:

const heroText = grain.getConfig('hero_text');
console.log(heroText); // Returns immediately

Behavior:

Returns cached value instantly
Returns default if provided
Returns undefined if not found
Triggers background refresh

getAllConfigs()

Get all configurations synchronously.

grain.getAllConfigs(): Record<string, string>

Returns: Object with all configuration key-value pairs Example:

const configs = grain.getAllConfigs();
console.log(configs);
// { hero_text: "Welcome", button_color: "blue", ... }

getConfigAsync()

Get configuration value asynchronously with cache-first strategy.

await grain.getConfigAsync(
  key: string,
  options?: RemoteConfigOptions
): Promise<string | undefined>

Parameters:

key - Configuration key
options.properties - User properties for personalization
options.forceRefresh - Skip cache, fetch from API
options.immediateKeys - Keys to fetch immediately

Returns: Promise resolving to configuration value Example:

// Basic usage
const value = await grain.getConfigAsync('hero_text');

// With personalization
const value = await grain.getConfigAsync('hero_text', {
  properties: {
    plan: 'premium',
    location: 'US'
  }
});

// Force refresh
const value = await grain.getConfigAsync('hero_text', {
  forceRefresh: true
});

getAllConfigsAsync()

Get all configurations asynchronously.

await grain.getAllConfigsAsync(
  options?: RemoteConfigOptions
): Promise<Record<string, string>>

Parameters:

options.properties - User properties for personalization
options.forceRefresh - Skip cache, fetch from API

Returns: Promise resolving to all configurations Example:

// Basic usage
const configs = await grain.getAllConfigsAsync();

// With personalization
const configs = await grain.getAllConfigsAsync({
  properties: {
    plan: 'premium',
    location: 'US'
  }
});

fetchConfig()

Fetch configurations directly from API.

await grain.fetchConfig(
  options?: RemoteConfigOptions
): Promise<RemoteConfigResponse>

Parameters:

options.immediateKeys - Keys to fetch immediately
options.properties - User properties for personalization
options.userId - User ID override

Returns: Promise resolving to full API response Example:

const response = await grain.fetchConfig({
  immediateKeys: ['hero_text', 'button_color'],
  properties: {
    plan: 'premium'
  }
});

console.log(response.configurations);
console.log(response.snapshotId);
console.log(response.qualifiedSegments);

Response includes:

configurations - Config key-value pairs
snapshotId - Configuration snapshot ID
qualifiedSegments - Matched user segments
qualifiedRuleSets - Matched rule sets
isFinal - Whether more configs may load
timestamp - Response timestamp

preloadConfig()

Preload configurations for immediate synchronous access.

await grain.preloadConfig(
  immediateKeys?: string[],
  properties?: Record<string, string>
): Promise<void>

Parameters:

immediateKeys - Specific keys to preload (optional, loads all if omitted)
properties - User properties for personalization

Returns: Promise that resolves when configs are loaded Example:

// Preload specific keys
await grain.preloadConfig(['hero_text', 'button_color']);

// Now available synchronously
const heroText = grain.getConfig('hero_text');

// Preload all configs
await grain.preloadConfig();

When to use:

App startup
Before rendering UI
Critical configs needed immediately

addConfigChangeListener()

Add listener for configuration changes.

grain.addConfigChangeListener(
  listener: ConfigChangeListener
): void

Parameters:

listener - Callback function receiving updated configs

Example:

const listener = (configurations) => {
  console.log('Configs updated:', configurations);
  // Update UI
};

grain.addConfigChangeListener(listener);

When listeners fire:

After background refresh completes
When manual refresh happens
When cache updates

removeConfigChangeListener()

Remove configuration change listener.

grain.removeConfigChangeListener(
  listener: ConfigChangeListener
): void

Parameters:

listener - Previously added listener function

Example:

grain.removeConfigChangeListener(listener);

When to remove:

Component unmounts
No longer need updates
Cleanup on destroy

Configuration Flow

Cache-first strategy:

getConfig() returns cached value (instant)
Background fetch starts automatically
When fresh data arrives, listeners fire
Cache updates for next access

Personalization: Pass properties to get user-specific values:

const message = await grain.getConfigAsync('welcome_message', {
  properties: {
    plan: user.plan,
    signup_date: user.signupDate,
    location: user.country
  }
});

Rules in dashboard determine which values match which users.

Next Steps

Remote Config

Learn configuration concepts

Core Methods

Event tracking methods

API Documentation

Query API

getConfig()

getAllConfigs()

getConfigAsync()

getAllConfigsAsync()

fetchConfig()

preloadConfig()

addConfigChangeListener()

removeConfigChangeListener()

Configuration Flow

Next Steps

Remote Config

Core Methods

​getConfig()

​getAllConfigs()

​getConfigAsync()

​getAllConfigsAsync()

​fetchConfig()

​preloadConfig()

​addConfigChangeListener()

​removeConfigChangeListener()

​Configuration Flow

​Next Steps

Remote Config

Core Methods

getConfig()

getAllConfigs()

getConfigAsync()

getAllConfigsAsync()

fetchConfig()

preloadConfig()

addConfigChangeListener()

removeConfigChangeListener()

Configuration Flow

Next Steps