json-api-nestjs

This plugin works upon TypeOrm or MicroOrm library, which is used as the main database abstraction layer tool. The module
automatically generates an API according to JSON API specification from the database structure (TypeOrm or MicroOrm entities). It
supports features such as requests validation based on database fields types, request filtering, endpoints extending,
data relations control and much more. Our module significantly reduces the development time of REST services by removing
the need to negotiate the mechanism of client-server interaction and implementing automatic API generation without the
need to write any code.

Installation

``bash
$ npm install json-api-nestjs
`

Example

Once the installation process is complete, we can import the JsonApiModule into the root AppModule.


$3


`typescript
import {Module} from '@nestjs/common';
import {JsonApiModule, TypeOrmJsonApiModule} from 'json-api-nestjs';
import {Users} from 'type-orm/database';

@Module({
imports: [
JsonApiModule.forRoot(TypeOrmJsonApiModule, {
entities: [Users]
}),
],
})
export class AppModule {
}
`

$3


`typescript
import {Module} from '@nestjs/common';
import {JsonApiModule, MicroOrmJsonApiModule} from 'json-api-nestjs';
import {Users} from 'micro-orm/database';

@Module({
imports: [
JsonApiModule.forRoot(MicroOrmJsonApiModule, {
entities: [Users]
}),
],
})
export class AppModule {
}
`

After this, you have to prepare CRUDs with ready-to-use endpoints:

- GET /users
- POST /users
- GET /users/:id
- PATCH /users/:id
- DELETE /users/:id
- GET /users/{id}/relationships/{relName}
- POST /users/{id}/relationships/{relName}
- PATCH /users/{id}/relationships/{relName}
- DELETE /users/{id}/relationships/{relName}

Configuration params

The following interface is using for the configuration:

`typescript
export interface ModuleOptions {
entities: Entity[]; // List of typeOrm Entity
controllers?: NestController[]; // List of controller, if you need extend default present
connectionName?: string; // Type orm connection name: "default" is default name
providers?: NestProvider[]; // List of addition provider for useing in custom controller
imports?: NestImport[]; // List of addition module for useing in custom controller
options?: {
requiredSelectField?: boolean; // Need list of select field in get endpoint, try is default
debug?: boolean; // Debug info in result object, like error message
pipeForId?: Type // Nestjs pipe for validate id params, by default ParseIntPipe
operationUrl?: string // Url for atomic operation https://jsonapi.org/ext/atomic/
// TypeOrm
useSoftDelete?: boolean // Use soft delete
runInTransaction?: any>(
isolationLevel: IsolationLevel,
fn: Func
) => ReturnType // You can use cutom function for wrapping transaction in atomic operation, example: runInTransaction from https://github.com/Aliheym/typeorm-transactional
// MicroOrm
arrayType?: string[]; //Custom type for indicate of array
};
}
`

You can extend the default controller:

`typescript
import {Get, Param, Inject, BadRequestException} from '@nestjs/common';

import {Users} from 'database';
import {
JsonApi,
excludeMethod,
JsonBaseController,
InjectService,
JsonApiService,
ResourceObjectRelationships,
Query,
} from 'json-api-nestjs';
import {ExampleService} from '../../service/example/example.service';

@JsonApi(Users, {
allowMethod: excludeMethod(['deleteRelationship']),
requiredSelectField: true,
overrideRoute: 'user',
})
export class ExtendUserController extends JsonBaseController {
@InjectService() public service: JsonApiService;
@Inject(ExampleService) protected exampleService: ExampleService;

public override getAll(query: Query): Promise> {
if (!this.exampleService.someCheck(query)) {
throw new BadRequestException({});
}
return this.service.getAll(query);// OR call parent method: super.getAll(query);
}

public override patchRelationship>(
id: string | number,
relName: Rel,
input: PatchRelationshipData
): Promise> {
return super.patchRelationship(id, relName, input);
}

@Get(':id/example')
testOne(@Param('id') id: string): string {
return this.exampleService.testMethode(id);
}
}
`

You can overwrite the default config for the current controller using options in the decorator JsonAPi.
Also you can specify an API method necessary for you, using allowMethod
Defulat validation check only simple type and database structure.
If you need custom pipe validation you can your owner pipe like this:

`typescript

import { Query } from '@nestjs/common';
import {
JsonApi,
excludeMethod,
JsonBaseController,
InjectService,
JsonApiService,
Query as QueryType,
} from 'json-api-nestjs';

@JsonApi(Users, {
allowMethod: excludeMethod(['deleteRelationship']),
requiredSelectField: true,
overrideRoute: 'user',
})
export class ExtendUserController extends JsonBaseController {
@InjectService() public service: JsonApiService;
@Inject(ExampleService) protected exampleService: ExampleService;

public override getAll(
@Query(ExamplePipe) query: QueryType
): Promise> {
return super.getAll(query);
}
}
`

`typescript
import { ArgumentMetadata, PipeTransform } from '@nestjs/common';

import { Query } from 'json-api-nestjs';
import { Users } from 'database';

export class ExamplePipe implements PipeTransform, Query> {
transform(value: Query, metadata: ArgumentMetadata): Query {
return value;
}
}
`

Swagger UI

For using swagger, you should only add @nestjs/swagger and configure it
`typescript
const app = await NestFactory.create(AppModule);

const config = new DocumentBuilder()
.setTitle('JSON API swagger example')
.setDescription('The JSON API list example')
.setVersion('1.0')
.build();

SwaggerModule.setup(
'swagger',
app,
() => SwaggerModule.createDocument(app, config), // !!!Important: document as factory
{}
);

`

Available endpoint method

Using Users entity and relation Roles entity as example

$3

`
GET /users
`

Available query params:

- include - you can extend result with relations (aka join)
`
GET /users?include=roles
`
result of request will have role relation for each Users item

- fields - you can specify required fields of result query

`
GET /users?fields[target]=login,lastName&fileds[roles]=name,key
`
The "target" is Users entity
The "roles" is Roles entity
So, result of request will be have only fields login and lastName for Users entity and fields name and *
key* for Roles entity
- sort - you can sort result of the request

`
GET /users?sort=target.name,-roles.key
`
The "target" is Users entity
The "roles" is Roles entity
So, result of the request will be sorted by field name of Users by ASC and field key of Roles entity
by DESC.
- page - pagination for you request

`
GET /users?page[number]=1page[size]=20
`
- filter - filter for query

`
GET /users?filter[name][eq]=1&filter[roles.name][ne]=test&filter[roles.status][eq]=true
`
The "name" is a field of Users entity
The "roles.name" is name field of Roles entity
The "eq", "ne" is Filter operand

So, this query will be transformed like sql:
`sql
WHERE users.name = 1 AND roles.name <> 'test' AND roles.status = true
`

Filter operand

`typescript
type FilterOperand
{
in:string[] // is equal to the conditional of query "WHERE 'attribute_name' IN ('value1', 'value2')"
nin: string[] // is equal to the conditional of query "WHERE 'attribute_name' NOT IN ('value1', 'value1')"
eq: string // is equal to the conditional of query "WHERE 'attribute_name' = 'value1'
ne: string // is equal to the conditional of query "WHERE 'attribute_name' <> 'value1'
gte: string // is equal to the conditional of query "WHERE 'attribute_name' >= 'value1'
gt: string // is equal to the conditional of query "WHERE 'attribute_name' > 'value1'
lt: string // is equal to the conditional of query "WHERE 'attribute_name' < 'value1'
lte:string // is equal to the conditional of query "WHERE 'attribute_name' <= 'value1'
regexp: string // is equal to the conditional of query "WHERE 'attribute_name' ~* value1
some: string // is equal to the conditional of query "WHERE 'attribute_name' && [value1]
}
`

$3

`
GET /users/:id
`
- include - you can extend result with relations (aka join)
`
GET /users?include=roles
`
result of request will have role relation for each Users item

- fields - you can specify required fields of result query

`
GET /users?fields[target]=login,lastName&fileds[roles]=name,key
`
The "target" is Users entity
The "roles" is Roles entity
So, result of request will be have only fields login and lastName for Users entity and fields name and *
key* for Roles entity

$3


`
POST /users
`

- body - Create new User and add link to address

`json
{
"data": {
"type": "users",
"attributes": {
"id": 0,
"login": "string",
"firstName": "string",
"lastName": "string",
"isActive": true,
"createdAt": "2023-12-08T10:32:27.352Z",
"updatedAt": "2023-12-08T10:32:27.352Z"
},
"relationships": {
"addresses": {
"id": "1",
"type": "addresses"
}
}
}
}
`


$3


`
PATCH /users/:id
`

- body - Update User with id 1 and update link to address and manager

`json
{
"data": {
"id": "1",
"type": "users",
"attributes": {
"id": 0,
"login": "string",
"firstName": "string",
"lastName": "string",
"isActive": true,
"createdAt": "2023-12-08T10:34:57.752Z",
"updatedAt": "2023-12-08T10:34:57.752Z"
},
"relationships": {
"addresses": {
"id": "2",
"type": "addresses"
},
"manager": {
"id": "2",
"type": "users"
}
}
}
}

`

$3

You can more information find here
But you have additinal feature.
For example: you will need create new Roles, then - create new Users and assign new Roles to new Users.
If use native json api you need send 3 http request:
- POST /roles
- POST /users

but Atomic operation allow for one request.
`json

{
"atomic:operations":[
{
"op":"add",
"ref":{
"type":"roles",
"tmpId":10000
},
"data":{
"type":"roles",
"attributes":{
"name":"testRolesAgain",
"key":"testRolesAgain"
}
}
},
{
"op":"add",
"ref":{
"type":"users"
},
"data":{
"type":"users",
"attributes":{
"login":"newLogin"
},
"relationships":{
"addresses":{
"type":"addresses",
"id":"1"
},
"roles":[
{
"type":"roles",
"id":"10000"
}
]
}
}
}
]
}

`
tmpId - is params for operation add, should be unique for all operations.
If you have Interceptor you can check call it from AtomicOperation

`ts
@Injectable()
export class AtomicInterceptor implements NestInterceptor {
intercept(context: ExecutionContext, next: CallHandler): Observable {
const isAtomic = context.getArgByIndex(3)
if (isAtomic) {
console.log('call from atomic operation')
}
return next.handle();
}
}
``
isAtomic - is array of params of method