diff options
Diffstat (limited to 'Timeline/ClientApp/src/app/data/timeline.ts')
| -rw-r--r-- | Timeline/ClientApp/src/app/data/timeline.ts | 133 |
1 files changed, 62 insertions, 71 deletions
diff --git a/Timeline/ClientApp/src/app/data/timeline.ts b/Timeline/ClientApp/src/app/data/timeline.ts index b30f3a7d..8680e9b8 100644 --- a/Timeline/ClientApp/src/app/data/timeline.ts +++ b/Timeline/ClientApp/src/app/data/timeline.ts @@ -32,7 +32,7 @@ import { HttpTimelineNameConflictError,
HttpTimelineGenericPostInfo,
} from '../http/timeline';
-import { BlobWithEtag, NotModified } from '../http/common';
+import { BlobWithEtag, NotModified, HttpNetworkError } from '../http/common';
export type TimelineInfo = HttpTimelineInfo;
export type TimelineChangePropertyRequest = HttpTimelinePatchRequest;
@@ -76,23 +76,17 @@ export interface TimelinePostListState { posts: TimelinePostInfo[];
}
-export interface TimelineInfoLoadingState {
- state: 'loading'; // Loading from cache.
- timeline: null;
-}
-
-export interface TimelineInfoNonLoadingState {
- state:
- | 'syncing' // Cache loaded and syncing now. If null means there is no cache for the timeline.
- | 'offline' // Sync failed and use cache.
- | 'synced' // Sync succeeded. If null means the timeline does not exist.
- | 'new'; // This is a new timeline different from cached one. If null means the timeline does not exist.
- timeline: TimelineInfo | null;
-}
-
-export type TimelineInfoState =
- | TimelineInfoLoadingState
- | TimelineInfoNonLoadingState;
+export type TimelineWithSyncState =
+ | {
+ syncState:
+ | 'offline' // Sync failed and use cache. Null timeline means no cache.
+ | 'synced'; // Sync succeeded. Null timeline means the timeline does not exist.
+ timeline: TimelineInfo | null;
+ }
+ | {
+ syncState: 'new'; // This is a new timeline different from cached one.
+ timeline: TimelineInfo;
+ };
interface TimelineCache {
timeline: TimelineInfo;
@@ -112,43 +106,35 @@ export class TimelineService { return `timeline.${timelineName}`;
}
- private getCachedTimeline(
+ private async fetchAndCacheTimeline(
timelineName: string
- ): Promise<TimelineInfo | null> {
- return dataStorage
- .getItem<TimelineCache | null>(this.getTimelineKey(timelineName))
- .then((cache) => cache?.timeline ?? null);
- }
-
- private async syncTimeline(timelineName: string): Promise<TimelineInfo> {
+ ): Promise<
+ | { timeline: TimelineInfo; type: 'new' | 'cache' | 'synced' }
+ | 'offline'
+ | 'notexist'
+ > {
const cache = await dataStorage.getItem<TimelineCache | null>(timelineName);
+ const key = this.getTimelineKey(timelineName);
const save = (cache: TimelineCache): Promise<TimelineCache> =>
- dataStorage.setItem<TimelineCache>(
- this.getTimelineKey(timelineName),
- cache
- );
- const push = (state: TimelineInfoState): void => {
- this._timelineSubscriptionHub.update(timelineName, () =>
- Promise.resolve(state)
- );
- };
+ dataStorage.setItem<TimelineCache>(key, cache);
- let result: TimelineInfo;
const now = new Date();
if (cache == null) {
try {
- const res = await getHttpTimelineClient().getTimeline(timelineName);
- result = res;
- await save({ timeline: result, lastUpdated: now.toISOString() });
- push({ state: 'synced', timeline: result });
+ const timeline = await getHttpTimelineClient().getTimeline(
+ timelineName
+ );
+ await save({ timeline, lastUpdated: now.toISOString() });
+ return { timeline, type: 'synced' };
} catch (e) {
if (e instanceof HttpTimelineNotExistError) {
- push({ state: 'synced', timeline: null });
+ return 'notexist';
+ } else if (e instanceof HttpNetworkError) {
+ return 'offline';
} else {
- push({ state: 'offline', timeline: null });
+ throw e;
}
- throw e;
}
} else {
try {
@@ -157,50 +143,55 @@ export class TimelineService { ifModifiedSince: new Date(cache.lastUpdated),
});
if (res instanceof NotModified) {
- result = cache.timeline;
- await save({ timeline: result, lastUpdated: now.toISOString() });
- push({ state: 'synced', timeline: result });
+ const { timeline } = cache;
+ await save({ timeline, lastUpdated: now.toISOString() });
+ return { timeline, type: 'synced' };
} else {
- result = res;
- await save({ timeline: result, lastUpdated: now.toISOString() });
+ const timeline = res;
+ await save({ timeline, lastUpdated: now.toISOString() });
if (res.uniqueId === cache.timeline.uniqueId) {
- push({ state: 'synced', timeline: result });
+ return { timeline, type: 'synced' };
} else {
- push({ state: 'new', timeline: result });
+ return { timeline, type: 'new' };
}
}
} catch (e) {
if (e instanceof HttpTimelineNotExistError) {
- push({ state: 'new', timeline: null });
- } else {
- push({ state: 'offline', timeline: cache.timeline });
+ await dataStorage.removeItem(key);
+ return 'notexist';
+ } else if (e instanceof HttpNetworkError) {
+ return { timeline: cache.timeline, type: 'cache' };
}
throw e;
}
}
- return result;
}
private _timelineSubscriptionHub = new SubscriptionHub<
string,
- TimelineInfoState
- >(
- (key) => key,
- () => ({
- state: 'loading',
- timeline: null,
- }),
- async (key) => {
- const result = await this.getCachedTimeline(key);
- void this.syncTimeline(key);
- return {
- state: 'syncing',
- timeline: result,
- };
- }
- );
+ TimelineWithSyncState
+ >({
+ setup: (key, next) => {
+ void this.fetchAndCacheTimeline(key).then((result) => {
+ if (result === 'offline') {
+ next({ syncState: 'offline', timeline: null });
+ } else if (result === 'notexist') {
+ next({ syncState: 'synced', timeline: null });
+ } else {
+ const { type, timeline } = result;
+ if (type === 'cache') {
+ next({ syncState: 'offline', timeline });
+ } else if (type === 'synced') {
+ next({ syncState: 'synced', timeline });
+ } else {
+ next({ syncState: 'new', timeline });
+ }
+ }
+ });
+ },
+ });
- get timelineHub(): ISubscriptionHub<string, TimelineInfoState> {
+ get timelineHub(): ISubscriptionHub<string, TimelineWithSyncState> {
return this._timelineSubscriptionHub;
}
|