typeqsfind

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.