feat: implement TagsModule with service, controller, and endpoints

Added TagsModule to manage tags, including a TagsService for querying and sorting by popularity or recency. Created TagsController with endpoint to retrieve paginated and searchable tag data. Integrated with database and relevant schemas.

backend/src/tags/tags.controller.ts

@@ -0,0 +1,23 @@
+import {
+	Controller,
+	DefaultValuePipe,
+	Get,
+	ParseIntPipe,
+	Query,
+} from "@nestjs/common";
+import { TagsService } from "./tags.service";
+
+@Controller("tags")
+export class TagsController {
+	constructor(private readonly tagsService: TagsService) {}
+
+	@Get()
+	findAll(
+		@Query("limit", new DefaultValuePipe(10), ParseIntPipe) limit: number,
+		@Query("offset", new DefaultValuePipe(0), ParseIntPipe) offset: number,
+		@Query("query") query?: string,
+		@Query("sort") sort?: "popular" | "recent",
+	) {
+		return this.tagsService.findAll({ limit, offset, query, sortBy: sort });
+	}
+}

backend/src/tags/tags.module.ts

@@ -0,0 +1,12 @@
+import { Module } from "@nestjs/common";
+import { DatabaseModule } from "../database/database.module";
+import { TagsController } from "./tags.controller";
+import { TagsService } from "./tags.service";
+
+@Module({
+	imports: [DatabaseModule],
+	controllers: [TagsController],
+	providers: [TagsService],
+	exports: [TagsService],
+})
+export class TagsModule {}

backend/src/tags/tags.service.ts

@@ -0,0 +1,53 @@
+import { Injectable } from "@nestjs/common";
+import { desc, eq, ilike, sql } from "drizzle-orm";
+import { DatabaseService } from "../database/database.service";
+import { contentsToTags, tags } from "../database/schemas";
+
+@Injectable()
+export class TagsService {
+	constructor(private readonly databaseService: DatabaseService) {}
+
+	async findAll(options: {
+		limit: number;
+		offset: number;
+		query?: string;
+		sortBy?: "popular" | "recent";
+	}) {
+		const { limit, offset, query, sortBy } = options;
+
+		let whereClause = sql`1=1`;
+		if (query) {
+			whereClause = ilike(tags.name, `%${query}%`);
+		}
+
+		// Pour la popularité, on compte le nombre d'associations dans contentsToTags
+		if (sortBy === "popular") {
+			const data = await this.databaseService.db
+				.select({
+					id: tags.id,
+					name: tags.name,
+					slug: tags.slug,
+					count: sql<number>`count(${contentsToTags.contentId})`.as("usage_count"),
+				})
+				.from(tags)
+				.leftJoin(contentsToTags, eq(tags.id, contentsToTags.tagId))
+				.where(whereClause)
+				.groupBy(tags.id)
+				.orderBy(desc(sql`usage_count`))
+				.limit(limit)
+				.offset(offset);
+
+			return data;
+		}
+
+		const data = await this.databaseService.db
+			.select()
+			.from(tags)
+			.where(whereClause)
+			.orderBy(sortBy === "recent" ? desc(tags.createdAt) : desc(tags.name))
+			.limit(limit)
+			.offset(offset);
+
+		return data;
+	}
+}