...
;
});
```
### Data Management
#### `ClientDataManager`
Main class for data management.
```ts
const dataManager = new ClientDataManager({
defaultOptions: {
queries: {
staleTime: 300000, // 5 minutes
retry: 3,
refetchOnWindowFocus: false,
},
},
});
```
**Methods:**
##### `invalidateTag(tag, options?)`
Invalidate all queries with a specific tag.
```ts
await dataManager.invalidateTag('users');
await dataManager.invalidateTag('posts', {
repeat: {count: 3, interval: 1000}, // Retry invalidation
});
```
##### `invalidateTags(tags, options?)`
Invalidate queries that have all specified tags.
```ts
await dataManager.invalidateTags(['user', 'profile']);
```
##### `invalidateSource(dataSource, options?)`
Invalidate all queries for a data source.
```ts
await dataManager.invalidateSource(userDataSource);
```
##### `invalidateParams(dataSource, params, options?)`
Invalidate a specific query with exact parameters.
```ts
await dataManager.invalidateParams(userDataSource, {userId: 123});
```
##### `resetSource(dataSource)`
Reset (clear) all cached data for a data source.
```ts
await dataManager.resetSource(userDataSource);
```
##### `resetParams(dataSource, params)`
Reset cached data for specific parameters.
```ts
await dataManager.resetParams(userDataSource, {userId: 123});
```
##### `invalidateSourceTags(dataSource, params, options?)`
Invalidate queries based on tags generated by a data source.
```ts
await dataManager.invalidateSourceTags(userDataSource, {userId: 123});
```
### Utilities
#### `skipContext(fetchFunction)`
Utility to adapt existing fetch functions to data source interface.
```ts
// Existing function
async function fetchUser(params: {userId: number}) {
// ...
}
// Adapted for data source
const dataSource = makePlainQueryDataSource({
name: 'user',
fetch: skipContext(fetchUser), // Skips context and fetchContext params
});
```
#### `withCatch(fetchFunction, errorHandler)`
Adds standardized error handling to fetch functions.
```ts
const safeFetch = withCatch(fetchUser, (error) => ({error: true, message: error.message}));
```
#### `withCancellation(fetchFunction)`
Adds cancellation support to fetch functions.
```ts
const cancellableFetch = withCancellation(fetchFunction);
// Automatically handles AbortSignal from React Query
```
#### `getProgressiveRefetch(options)`
Creates a progressive refetch interval function.
```ts
const progressiveRefetch = getProgressiveRefetch({
minInterval: 1000, // Start with 1 second
maxInterval: 30000, // Max 30 seconds
multiplier: 2, // Double each time
});
const dataSource = makePlainQueryDataSource({
name: 'data',
fetch: skipContext(fetchData),
options: {
refetchInterval: progressiveRefetch,
},
});
```
#### `normalizeStatus(status, fetchStatus)`
Converts React Query statuses to DataLoader status.
```ts
const status = normalizeStatus('pending', 'fetching'); // 'loading'
```
#### Status and Error Utilities
```ts
// Get combined status from multiple states
const status = getStatus([user, posts, comments]);
// Get first error from multiple states
const error = getError([user, posts, comments]);
// Merge multiple statuses
const combinedStatus = mergeStatuses(['loading', 'success', 'error']); // 'error'
// Check if query key has a tag
const hasUserTag = hasTag(queryKey, 'users');
```
#### Key Composition Utilities
```ts
// Compose cache key for a data source
const key = composeKey(userDataSource, {userId: 123});
// Compose full key including tags
const fullKey = composeFullKey(userDataSource, {userId: 123});
```
#### Constants
```ts
import {idle} from '@gravity-ui/data-source';
// Special symbol for skipping query execution
const params = shouldFetch ? {userId: 123} : idle;
// Type-safe alternative to enabled: false
// Instead of:
const {data} = useQueryData(userDataSource, {userId: userId || ''}, {enabled: Boolean(userId)});
// Use:
const {data} = useQueryData(userDataSource, userId ? {userId} : idle);
// TypeScript correctly infers types for both branches
```
#### Query Options Composition
```ts
// Compose React Query options for plain queries
const plainOptions = composePlainQueryOptions(context, dataSource, params, options);
// Compose React Query options for infinite queries
const infiniteOptions = composeInfiniteQueryOptions(context, dataSource, params, options);
```
**Note:** These functions are primarily for internal use when creating custom data source implementations.
## Advanced Patterns
### Conditional Queries with Idle
Use `idle` to create conditional queries:
```ts
import {idle} from '@gravity-ui/data-source';
const ConditionalDataComponent: React.FC<{
userId?: number;
shouldLoadPosts: boolean;
}> = ({userId, shouldLoadPosts}) => {
// Load user only if userId is defined
const user = useQueryData(
userDataSource,
userId ? {userId} : idle
);
// Load posts only if user is loaded and flag is enabled
const posts = useQueryData(
userPostsDataSource,
user.data && shouldLoadPosts ? {userId: user.data.id} : idle
);
const combined = useQueryResponses([user, posts]);
return (
{user.data && }
{posts.data && }
);
};
```
### Data Transformation
Transform request parameters and response data:
```ts
const apiDataSource = makePlainQueryDataSource({
name: 'api-data',
transformParams: (params: {id: number}) => ({
userId: params.id,
apiVersion: 'v2',
format: 'json',
}),
transformResponse: (response: ApiResponse) => ({
user: response.data.user,
metadata: response.meta,
}),
fetch: skipContext(apiFetch),
});
```
### Tag-Based Cache Invalidation
Use tags for sophisticated cache management:
```ts
const userDataSource = makePlainQueryDataSource({
name: 'user',
tags: (params) => [`user:${params.userId}`, 'users', 'profiles'],
fetch: skipContext(fetchUser),
});
const userPostsDataSource = makePlainQueryDataSource({
name: 'user-posts',
tags: (params) => [`user:${params.userId}`, 'posts'],
fetch: skipContext(fetchUserPosts),
});
// Invalidate all data for specific user
await dataManager.invalidateTag('user:123');
// Invalidate all user-related data
await dataManager.invalidateTag('users');
```
### Error Handling with Types
Create type-safe error handling:
```ts
interface ApiError {
code: number;
message: string;
details?: Record