/**
* Copyright 2017 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { Query } from '../core/query';
import { SnapshotVersion } from '../core/snapshot_version';
import { ProtoByteString, TargetId } from '../core/types';
import { emptyByteString } from '../platform/platform';
/** An enumeration of the different purposes we have for queries. */
export enum QueryPurpose {
/** A regular, normal query. */
Listen,
/**
* The query was used to refill a query after an existence filter mismatch.
*/
ExistenceFilterMismatch,
/** The query was used to resolve a limbo document. */
LimboResolution
}
/**
* An immutable set of metadata that the local store tracks for each query.
*/
export class QueryData {
constructor(
/** The query being listened to. */
public query: Query,
/**
* The target ID to which the query corresponds; Assigned by the
* LocalStore for user listens and by the SyncEngine for limbo watches.
*/
public targetId: TargetId,
/** The purpose of the query. */
public purpose: QueryPurpose,
/** The latest snapshot version seen for this target. */
public snapshotVersion: SnapshotVersion = SnapshotVersion.MIN,
/**
* An opaque, server-assigned token that allows watching a query to be
* resumed after disconnecting without retransmitting all the data that
* matches the query. The resume token essentially identifies a point in
* time from which the server should resume sending results.
*/
public resumeToken: ProtoByteString = emptyByteString()
) {}
/**
* Creates a new query data instance with an updated snapshot version and
* resume token.
*/
update(updated: {
resumeToken: ProtoByteString;
snapshotVersion: SnapshotVersion;
}): QueryData {
return new QueryData(
this.query,
this.targetId,
this.purpose,
updated.snapshotVersion,
updated.resumeToken
);
}
isEqual(other: QueryData): boolean {
return (
this.targetId === other.targetId &&
this.purpose === other.purpose &&
this.snapshotVersion.isEqual(other.snapshotVersion) &&
this.resumeToken === other.resumeToken &&
this.query.isEqual(other.query)
);
}
}
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