woltage/dist/src/ProjectionMap.js

A CQRS and Event-Sourcing Framework

import Projection from "./read/Projection.js";
export default class ProjectionMap {
    constructor() {
        this.idMap = new Map();
        this.activeProjectionMap = new Map();
    }
    add(projection) {
        this.idMap.set(projection.id, projection);
    }
    setActive(projectionName, projectionVersion, force = false) {
        const projectionId = Projection.getId(projectionName, projectionVersion);
        if (!this.idMap.has(projectionId))
            throw new Error(`Unknown projection '${projectionName}@${projectionVersion}'`);
        const projection = this.idMap.get(projectionId);
        if (!projection.isLiveTracking && !force)
            throw new Error(`Projection '${projectionName}@${projectionVersion}' is not tracking live events.`);
        this.activeProjectionMap.set(projectionName, projection);
    }
    getActive(projectionName) {
        return this.activeProjectionMap.get(projectionName);
    }
    get(nameOrId, projectionVersion) {
        const projectionId = typeof projectionVersion !== 'number'
            ? nameOrId
            : Projection.getId(nameOrId, projectionVersion);
        return this.idMap.get(projectionId);
    }
    async remove(projectionName, projectionVersion, force = false) {
        const projection = this.get(projectionName, projectionVersion);
        if (!projection)
            return;
        const isActive = this.getActive(projectionName) === projection;
        if (!force && isActive)
            throw new Error(`Can not remove active projection '${projectionName}@${projectionVersion}'.`);
        await projection.stop();
        this.idMap.delete(projection.id);
        if (isActive)
            this.activeProjectionMap.delete(projectionName);
    }
    async init() {
        await Promise.all([...this.idMap.values()].map(projection => projection.init()));
    }
    async stop() {
        await Promise.all([...this.idMap.values()].map(projection => projection.stop()));
    }
}