nosql-constraints/dist/constraints/constraints.js

Helpers to manage constrants (i.e. cascade delete) in a NoSQL database

import _ from 'lodash';
/**
 * Constraints class, supporting fast access to the constraints
 */
export class Constraints {
    constraintsGraph;
    constraintsMap;
    constructor(constraintsGraph, constraintsMap) {
        this.constraintsGraph = constraintsGraph;
        this.constraintsMap = constraintsMap;
    }
    getDirectConstraints(containerId, refDocType, cascadeDelete) {
        // Find vertices that match the refDocType and return the direct constraints (first element of each path)
        const constraints = [];
        const constraintEdgesSet = new Set();
        for (const [vertex, paths] of this.constraintsMap.entries()) {
            if (containerId === vertex.vertex.containerId &&
                _.isMatch(refDocType ?? {}, vertex.vertex.refDocType ?? {})) {
                for (const path of paths) {
                    if (path.length > 0) {
                        const edgeId = `${path[0].fromId} -> ${path[0].toId}`;
                        if (!constraintEdgesSet.has(edgeId) &&
                            (cascadeDelete === undefined ||
                                (path[0].constraint.cascadeDelete ?? false) === cascadeDelete)) {
                            constraintEdgesSet.add(edgeId);
                            constraints.push(path[0]);
                        }
                    }
                }
            }
        }
        return constraints;
    }
    getDirectCascadeDeleteConstraints(containerId, refDocType) {
        return this.getDirectConstraints(containerId, refDocType, true);
    }
    getDirectNoCascadeDeleteConstraints(containerId, refDocType) {
        return this.getDirectConstraints(containerId, refDocType, false);
    }
}