Create a filter pipe

back/src/song/song.controller.ts

@@ -1,5 +1,4 @@
 import {
-	BadRequestException,
 	Body,
 	ConflictException,
 	Controller,
@@ -26,14 +25,23 @@ import { createReadStream, existsSync } from 'fs';
 import { ApiTags, ApiUnauthorizedResponse } from '@nestjs/swagger';
 import { HistoryService } from 'src/history/history.service';
 import { JwtAuthGuard } from 'src/auth/jwt-auth.guard';
+import { FilterQuery } from 'src/utils/filter.pipe';
 
 @Controller('song')
 @ApiTags('song')
 export class SongController {
+	static filterableFields: string[] = [
+		'+id',
+		'name',
+		'+artistId',
+		'+albumId',
+		'+genreId',
+	];
+
 	constructor(
 		private readonly songService: SongService,
 		private readonly historyService: HistoryService,
-	) { }
+	) {}
 
 	@Get(':id/midi')
 	async getMidi(@Param('id', ParseIntPipe) id: number) {
@@ -104,24 +112,16 @@ export class SongController {
 	@Get()
 	async findAll(
 		@Req() req: Request,
-		@Query() filter: Prisma.SongWhereInput,
+		@FilterQuery(SongController.filterableFields) where: Prisma.SongWhereInput,
 		@Query('skip', new DefaultValuePipe(0), ParseIntPipe) skip: number,
 		@Query('take', new DefaultValuePipe(20), ParseIntPipe) take: number,
 	): Promise<Plage<Song>> {
-		try {
-			const ret = await this.songService.songs({
-				skip,
-				take,
-				where: {
-					...filter,
-					id: filter.id ? +filter.id : undefined,
-				},
-			});
-			return new Plage(ret, req);
-		} catch (e) {
-			console.log(e);
-			throw new BadRequestException(null, e?.toString());
-		}
+		const ret = await this.songService.songs({
+			skip,
+			take,
+			where,
+		});
+		return new Plage(ret, req);
 	}
 
 	@Get(':id')

back/src/utils/filter.pipe.ts

@@ -0,0 +1,35 @@
+import {
+	BadRequestException,
+	Injectable,
+	PipeTransform,
+	Query,
+} from '@nestjs/common';
+
+@Injectable()
+export class FilterPipe implements PipeTransform {
+	constructor(private readonly fields: string[]) {}
+
+	transform(value: Record<string, string>) {
+		const filter = {};
+		for (const fieldIdentifier of this.fields) {
+			const field = fieldIdentifier.startsWith('+')
+				? fieldIdentifier.slice(1)
+				: fieldIdentifier;
+
+			if (value[field] === undefined) continue;
+
+			if (fieldIdentifier.startsWith('+')) {
+				filter[field] = parseInt(value[field]);
+				if (isNaN(filter[field]))
+					throw new BadRequestException(
+						`Invalid filter, ${field} should be a number but it was ${value[field]}.`,
+					);
+			} else filter[field] = value[field];
+		}
+		return filter;
+	}
+}
+
+export function FilterQuery(fields: string[]) {
+	return Query(new FilterPipe(fields));
+}