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filtermatrix

v1.0.4

Published

Define relationships between selectors as a matrix of filter functions

Downloads

1

Readme

FilterMatrix

Define relationships between selectors as a matrix of filter functions

npm install --save filtermatrix

Define your filters:

Filters must be in the form (items: TItem[], value: TValue) => TItem[]

Where items is the list to be filtered and value is an item selected on another selector

interface Relations: {
    buildingContract: BuildingContract[];
}

//A function that get your filter functions:
const getBaseFilters = (relations: Relations)  => ({
    //A filter between buildings and machine, note that there is a Many-To-One relationship between buildings and machines
    buildingsByMachine: (buildings: Building[], machine: Machine | undefined) =>
            machine ?
            buildings.filter(x => x.idBuilding == machine.idBuilding) : 
            buildings
            ,

    //A filter between buildings and contract, there is a many-to-many relationship between buildings and contracts
    buildingsByContract: (buildings: Building[], contract: Contract | undefined) =>       
        contract ?       
        manyToManyFilter(relations.buildingContract, buildings, contract.idContract, x => x.idBuilding, x => x.idBuilding, x => x.idContract) :
        buildings
})
    

Build the matrix from a row of filters

function getFilterMatrix(data: Data) {
    const { buildingByContract, buldingsByMachine} = getFilters(data);
    const row = { building: x => x, contract: buildingByContract, machine: buldingsByMachine};

    return createMatrixFromRow(row, "building")(data.buildings);
}

Or build the filter matrix manually

type ItemTypes = {
    building: Building;
    contract: Contract;
    machine: Machine;
}

type Data = { [K in keyof ItemTypes]: ItemTypes[K]} & Relations;

function getFilterMatrix(data: Data) {
    const { buildingByContract, buldingsByMachine} = getFilters(data);

    //Idempotent function, a filter that pass the input as-is
    const idem = x => x;
    const matrix: FilterMatrix<ItemTypes> = {
        building: {
            building: idem,
            contract: buildingsByContract,
            machine: buildingsByMachine,
        },
        contract: {
            building: invertFilter(buildingsByContract),
            contract: idem,
            machine: joinFilter(buildingsByContract, buildingsByMachine)(data.buildings),
        },
        machine: {
            building: invertFilter(buildingsByMachine),
            contract:  joinFilter(buildingsByMachine, buildingsByContract)(data.buildings),
            machine: idem
        }
    };

    return applyMatrix(matrix)(data);
}

Apply the filter matrix:


//Return all lists, filtered by the given selected items
const selectedValues = {
    contract: data.contracts[1],
    machine: data.machine[6]
};
const myMatrix = getFilterMatrix(data);
const filteredLists = myMatrix(selectedValues);