Rapiq (Rest Api Query) is a library to build an efficient interface between client- & server-side applications. It defines a format for the request, but not for the response.
Table of Contents
npm install rapiq --save
To read the docs, visit https://rapiq.tada5hi.net
fields
- Description: Return only specific fields or extend the default selection.
- URL-Parameter: fields
filters
- Description: Filter the data set, according to specific criteria.
- URL-Parameter: filter
relations
- Description: Include related resources of the primary data.
- URL-Parameter: include
pagination
- Description: Limit the number of resources returned from the entire collection.
- URL-Parameter: page
sort
- Description: Sort the resources according to one or more keys in asc/desc direction.
- URL-Parameter: sort
It is based on the JSON-API specification.
This is a small outlook on how to use the library. For detailed explanations and extended examples, read the docs.
The first step is to construct a BuildInput object for a generic Record <T>
and
pass it to the buildQuery method to convert it to a string.
The result string can then be provided as a URL query string to a backend application. The backend application can than process the request, by parsing the query string.
The following example should give an insight on how to use this library.
Therefore, a type which will represent a User
and a method getAPIUsers
are defined.
The method should perform a request to the resource API to receive a collection of entities.
import axios from "axios";
import {
buildQuery,
BuildInput
} from "rapiq";
type Profile = {
id: number;
avatar: string;
cover: string;
}
type User = {
id: number;
name: string;
age?: number;
profile: Profile;
}
type ResponsePayload = {
data: User[],
meta: {
limit: number,
offset: number,
total: number
}
}
export async function getAPIUsers(
record: BuildInput<User>
): Promise<ResponsePayload> {
const response = await axios.get('users' + buildQuery(record));
return response.data;
}
(async () => {
const record: BuildInput<User> = {
pagination: {
limit: 20,
offset: 10
},
filters: {
id: 1 // some possible values:
// 1 | [1,2,3] | '!1' | '~1' | ['!1',2,3] | {profile: {avatar: 'xxx.jpg'}}
},
fields: ['id', 'name'], // some possible values:
// 'id' | ['id', 'name'] | '+id' | {user: ['id', 'name'], profile: ['avatar']}
sort: '-id', // some possible values:
// 'id' | ['id', 'name'] | '-id' | {id: 'DESC', profile: {avatar: 'ASC'}}
relations: {
profile: true
}
};
const query = buildQuery(record);
// console.log(query);
// ?filter[id]=1&fields=id,name&page[limit]=20&page[offset]=10&sort=-id&include=profile
let response = await getAPIUsers(record);
// do something with the response :)
})();
The next section will describe, how to parse the query string on the backend side.
For explanation purposes, two simple entities with a basic relation between them are declared to demonstrate the usage on the backend side. Therefore, typeorm is used as ORM for the database.
entities.ts
import {
Entity,
PrimaryGeneratedColumn,
Column,
OneToOne,
JoinColumn
} from "typeorm";
@Entity()
export class User {
@PrimaryGeneratedColumn({unsigned: true})
id: number;
@Column({type: 'varchar', length: 30})
@Index({unique: true})
name: string;
@Column({type: 'varchar', length: 255, default: null, nullable: true})
email: string;
@OneToOne(() => Profile)
profile: Profile;
}
@Entity()
export class Profile {
@PrimaryGeneratedColumn({unsigned: true})
id: number;
@Column({type: 'varchar', length: 255, default: null, nullable: true})
avatar: string;
@Column({type: 'varchar', length: 255, default: null, nullable: true})
cover: string;
@OneToOne(() => User)
@JoinColumn()
user: User;
}
import { Request, Response } from 'express';
import {
parseQuery,
Parameter,
ParseOutput
} from 'rapiq';
import {
applyQueryParseOutput,
useDataSource
} from 'typeorm-extension';
/**
* Get many users.
*
* ...
*
* @param req
* @param res
*/
export async function getUsers(req: Request, res: Response) {
// const {fields, filter, include, page, sort} = req.query;
const output: ParseOutput = parseQuery(req.query, {
fields: {
defaultAlias: 'user',
allowed: ['id', 'name', 'profile.id', 'profile.avatar']
},
filters: {
defaultAlias: 'user',
allowed: ['id', 'name', 'profile.id']
},
relations: {
allowed: ['profile']
},
pagination: {
maxLimit: 20
},
sort: {
defaultAlias: 'user',
allowed: ['id', 'name', 'profile.id']
}
});
const dataSource = await useDataSource();
const repository = dataSource.getRepository(User);
const query = repository.createQueryBuilder('user');
// -----------------------------------------------------
// apply parsed data on the db query.
const parsed = applyQueryParseOutput(query, output);
// -----------------------------------------------------
const [entities, total] = await query.getManyAndCount();
return res.json({
data: {
data: entities,
meta: {
total,
...output.pagination
}
}
});
}