Sieve js filter builder example. git - https://github.com/Biarity/Sieve

1.httpQueryBuilder.d.ts

declare const enum RequestFilterOperator {
    Equals,
    NotEquals,
    GreaterThan,
    LessThan,
    GreaterThanOrEqualTo,
    LessThanOrEqualTo,
    Contains,
    StartsWith,
    CaseInsensitiveStringContains,
    CaseInsensitiveStringStartsWith,
    CaseInsensitiveStringEquals
}

declare const enum RequestSortDirection {
    Asc,
    Desc
}

interface IRequestFilter {
    parameter: string;
    operator: RequestFilterOperator;
    value: string | number;
}

interface IRequestSort {
    parameter: string;
    direction: RequestSortDirection;
}

interface IRequestQueryBuilder {
    filters: IRequestFilter[];
    sorts: IRequestSort[];
    page: number;
    pageSize: number;
    buildQuery(): string;
}

2.httpQueryBuilder.ts

class RequestQueryBuilder implements IRequestQueryBuilder {
    filters: IRequestFilter[];
    sorts: IRequestSort[];
    page: number;
    pageSize: number;


    constructor() {
        this.filters = new Array<IRequestFilter>();
        this.sorts = new Array<IRequestSort>();
        this.page = 1;
        this.pageSize = 100;
    }


    buildQuery(): string {
        let result = "filters=";

        this.filters.forEach((f, i) => {
            let translatedOperator = "";
            switch (f.operator) {
                case RequestFilterOperator.Equals:
                    translatedOperator = "==";
                    break;
                case RequestFilterOperator.NotEquals:
                    translatedOperator = "!=";
                    break;
                case RequestFilterOperator.GreaterThan:
                    translatedOperator = ">";
                    break;
                case RequestFilterOperator.LessThan:
                    translatedOperator = "<";
                    break;
                case RequestFilterOperator.GreaterThanOrEqualTo:
                    translatedOperator = ">=";
                    break;
                case RequestFilterOperator.LessThanOrEqualTo:
                    translatedOperator = "<=";
                    break;
                case RequestFilterOperator.Contains:
                    translatedOperator = "@=";
                    break;
                case RequestFilterOperator.StartsWith:
                    translatedOperator = "_=";
                    break;
                case RequestFilterOperator.CaseInsensitiveStringContains:
                    translatedOperator = "@=*";
                    break;
                case RequestFilterOperator.CaseInsensitiveStringStartsWith:
                    translatedOperator = "_=*";
                    break;
                case RequestFilterOperator.CaseInsensitiveStringEquals:
                    translatedOperator = "==*";
                    break;
            }

            result += (i === 0 ? "" : ",") + (f.parameter + translatedOperator + f.value);
        });

        result += "&sorts=";
        this.sorts.forEach((s, i) => {
            let translatedValue = "";
            switch (s.direction) {
                case RequestSortDirection.Asc:
                    translatedValue = s.parameter;
                    break;
                case RequestSortDirection.Desc:
                    translatedValue = `-${s.parameter}`;
                    break;
            }
            result += (i === 0 ? "" : ",") + translatedValue;
        });

        result += `&page=${this.page}&pageSize=${this.pageSize}`;
        return result;
    }
}

3.httpQueryBuilderExample.ts

let httpQueryBuilder = new RequestQueryBuilder();

httpQueryBuilder.filters.push({
  parameter: "my_parameter",
  operator: RequestFilterOperator.CaseInsensitiveStringContains,
  value: "my_value"
});

httpQueryBuilder.filters.push({
  parameter: "mpr",
  operator: RequestFilterOperator.Equals,
  value: "mvl"
});

httpQueryBuilder.sorts.push({
  parameter: "mpr",
  direction: RequestSortDirection.Asc
});

let query = httpQueryBuilder.buildQuery();
console.log(`https://my.site.com?${query}`);
// https://my.site.com?filters=my_parameter@=*my_value,mpr==mvl&sorts=mpr&page=1&pageSize=100