TypeORM Query String Translator

Translates the HTTP Query String from an Express Request object to a TypeORM FindManyOptions object.

Installation

npm i -S typeqsfind

Usage

The example below presumes that you have a database configured with a single table named 'user'

ID | Name | Level ---|------|------ 1 | Jon | 9 2 | Nancy | 11

import {typeqs} from "typeqsfind";
import {FindManyOptions, createConnection, Repository} from "typeorm";
import express from "express";
import {Request, Response} from "express";
import {User} from "./entity/User";
import ormconfig from "./ormconfig";

const app = express();

let conn = await createConnection(ormconfig);

app.get("/users", async (req: Request, res: Response) => {
    let myOptions: FindManyOptions = typeqs.TranslateQuery(request);

    // myOptions is now a TypeORM FindManyOptions object taken from the query string
    let repo = getRepository(User);
    let results = await repo.find(myOptions);
    return results;
});

app.listen(3000);

Example Queries

GET http://localhost:3000/users?whereName=Jon
// Returns record 1

GET http://localhost:3000/users?whereName=Nancy
// Returns record 2

GET http://localhost:3000/users?greaterthanLevel=10
// Returns record 2

Production warning

This code is in experimental status. Using this code in production should only happen if you have completed extensive testing after integration with your own software.

Supported features

• Supports referencing nested relationships from the query string.
• Supports all common simple clause types (listed below)
• Supports sending a JSON object either encoded on the query string, or in the request body that will become the options object that you want. This is used as a starting point (if provided) to add more parameters to as provided from the query string.
• Supports typescript.
• Preliminary tests have been completed.

Supported Query String Operators

The following query string parameters are supported, and will be translated in the following ways:

NOTE: The query string examples in the Example column have not been properly URLEncoded. Please always make sure your query strings are properly encoded.

Prefix | SQL equivalent | Query String Example -------|-------------|-------- limit | LIMIT ? (Default 10) | ?limit=100 where | WHERE Name = ? | ?whereName=Jon orwhere | WHERE (Name = ? OR Name = ? | ?orwhereName[]=Jon&orwhereName[]=Nancy inarray | WHERE Name IN (?,?) | ?inarrayName[]=Jon&inarrayName[]=Nancy notinarray | WHERE Name NOT IN (?,?) | ?notinarrayName[]=Jon&notinarrayName[]=Nancy between | WHERE Name BETWEEN ? AND ? | ?betweenLevel[]=4&betweenLevel[]=10 isnull | WHERE Name IS NULL | ?isnullName isnotnull | WHERE Name IS NOT NULL | ?isnotnullName like | WHERE Name LIKE ? | ?likeName=%Jon% ilike | WHERE Name ILIKE ? | ?ilikeName=%jon% greaterthan | WHERE Level > ? | ?greaterthanLevel=10 greaterthanorequalto | WHERE Level >= ? | ?greaterthanorequaltoLevel=10 lessthan | WHERE Level < ? | ?lessthanLevel=10 lessthanorequalto | WHERE Level <= ? | ?lessthanorequaltoLevel=10 with | (joins a table and selects) | ?with[]=Sponsors orderby | ORDER BY Name | ?orderbyName=DESC

Referencing Nested Relations

Nested relations can be referenced with a dot operator between relation names and field names.

Consider a fundraiser schema as follows:

Table Beneficiaries

BenficiaryId | FirstName | LastName | Phone -------------|-----------|----------|------ 1 | Jon | Watson | 555-1212 2 | Sherlock | Holmes | 555-2121

Table Sponsors

SponsorId | FirstName | LastName | Phone | AmountCommitted | BeneficiaryId ----------|-----------|----------|-------|-----------------|-------------- 1 | Jill | Clemons | 555-1111 | 300 | 1 2 | Fred | Baker | 555-2222 | 200 | 2

http://localhost:3000/beneficiaries?greaterthanSponsors.AmountCommitted=250
// Returns Beneficiary 1

Extras

ORDER BY array syntax

More than one order by can be used in either syntax. But the array syntax is simply a different preference.

Example

?orderby[]=Name|DESC&orderby[]=Phone|ASC

Providing an options object

There are two different ways to provide an options JSON object to the request:

1. As a base64 encoded string using the options query string parameter. ?options=base64EncodedString
2. As the request body. Using express bodyParser.json() is helpful for this because it automatically parses JSON input and makes it available via request.body.