Add Document Export Functionality

backend/package.json

@@ -35,7 +35,10 @@
 		"@prisma/client": "^5.8.1",
 		"class-transformer": "^0.5.1",
 		"class-validator": "^0.14.1",
+		"fs-extra": "^11.2.0",
+		"html-pdf-node": "^1.0.8",
 		"langchain": "^0.1.9",
+		"markdown-it": "^14.1.0",
 		"markdown-to-txt": "^2.0.1",
 		"moment": "^2.30.1",
 		"passport-github": "^1.1.0",

backend/src/files/files.controller.ts

@@ -1,9 +1,20 @@
-import { Body, Controller, Get, HttpRedirectResponse, Param, Post, Redirect } from "@nestjs/common";
+import {
+	Body,
+	Controller,
+	Get,
+	HttpRedirectResponse,
+	InternalServerErrorException,
+	Param,
+	Post,
+	Redirect,
+	StreamableFile,
+} from "@nestjs/common";
+import { ApiBody, ApiOperation, ApiResponse } from "@nestjs/swagger";
+import { Public } from "src/utils/decorators/auth.decorator";
+import { CreateUploadPresignedUrlDto } from "./dto/create-upload-url.dto";
 import { FilesService } from "./files.service";
-import { ApiResponse, ApiOperation, ApiBody } from "@nestjs/swagger";
 import { CreateUploadPresignedUrlResponse } from "./types/create-upload-url-response.type";
-import { CreateUploadPresignedUrlDto } from "./dto/create-upload-url.dto";
-import { Public } from "src/utils/decorators/auth.decorator";
+import { ExportFileRequestBody } from "./types/export-file.type";
 
 @Controller("files")
 export class FilesController {
@@ -32,7 +43,7 @@ export class FilesController {
 	@Redirect()
 	@ApiOperation({
 		summary: "Create Presigned URL for Download",
-		description: "Create rresigned URL for download",
+		description: "Create Presigned URL for download",
 	})
 	async createDownloadPresignedUrl(
 		@Param("file_name") fileKey: string
@@ -42,4 +53,27 @@ export class FilesController {
 			statusCode: 302,
 		};
 	}
+
+	@Post("export-markdown")
+	@ApiOperation({
+		summary: "Export Markdown",
+		description: "Export Markdown to various formats",
+	})
+	@ApiBody({ type: ExportFileRequestBody })
+	@ApiResponse({ status: 200, description: "File exported successfully" })
+	async exportMarkdown(
+		@Body() exportFileRequestBody: ExportFileRequestBody
+	): Promise<StreamableFile> {
+		try {
+			const { fileContent, mimeType, fileName } =
+				await this.filesService.exportMarkdown(exportFileRequestBody);
+
+			return new StreamableFile(fileContent, {
+				type: mimeType,
+				disposition: `attachment; filename="${fileName}"`,
+			});
+		} catch (error) {
+			throw new InternalServerErrorException(`Failed to export file: ${error.message}`);
+		}
+	}
 }

backend/src/files/files.service.ts

@@ -1,20 +1,26 @@
+import { GetObjectCommand, PutObjectCommand, S3Client } from "@aws-sdk/client-s3";
+import { getSignedUrl } from "@aws-sdk/s3-request-presigner";
 import {
+	BadRequestException,
 	Injectable,
+	InternalServerErrorException,
 	NotFoundException,
 	UnauthorizedException,
 	UnprocessableEntityException,
 } from "@nestjs/common";
-import { S3Client, GetObjectCommand, PutObjectCommand } from "@aws-sdk/client-s3";
-import { getSignedUrl } from "@aws-sdk/s3-request-presigner";
 import { ConfigService } from "@nestjs/config";
-import { generateRandomKey } from "src/utils/functions/random-string";
-import { PrismaService } from "src/db/prisma.service";
 import { Workspace } from "@prisma/client";
+import * as htmlPdf from "html-pdf-node";
+import * as MarkdownIt from "markdown-it";
+import { PrismaService } from "src/db/prisma.service";
+import { generateRandomKey } from "src/utils/functions/random-string";
 import { CreateUploadPresignedUrlResponse } from "./types/create-upload-url-response.type";
+import { ExportFileRequestBody, ExportFileResponseDto } from "./types/export-file.type";
 
 @Injectable()
 export class FilesService {
 	private s3Client: S3Client;
+	private readonly markdown = new MarkdownIt();
 
 	constructor(
 		private configService: ConfigService,
@@ -68,4 +74,63 @@ export class FilesService {
 			throw new NotFoundException();
 		}
 	}
+
+	async exportMarkdown(
+		exportFileRequestBody: ExportFileRequestBody
+	): Promise<ExportFileResponseDto> {
+		const { exportType, content, fileName } = exportFileRequestBody;
+
+		try {
+			switch (exportType) {
+				case "markdown":
+					return this.exportToMarkdown(content, fileName);
+				case "html":
+					return this.exportToHtml(content, fileName);
+				case "pdf":
+					return this.exportToPdf(content, fileName);
+				default:
+					throw new BadRequestException("Invalid export type");
+			}
+		} catch (error) {
+			if (error instanceof BadRequestException) {
+				throw error;
+			}
+			throw new InternalServerErrorException(
+				`Failed to export ${exportType} file: ${error.message}`
+			);
+		}
+	}
+
+	private async exportToMarkdown(
+		content: string,
+		fileName: string
+	): Promise<ExportFileResponseDto> {
+		return {
+			fileContent: Buffer.from(content),
+			mimeType: "text/markdown",
+			fileName: `${fileName}.md`,
+		};
+	}
+
+	private async exportToHtml(content: string, fileName: string): Promise<ExportFileResponseDto> {
+		const html = this.markdown.render(content);
+		return {
+			fileContent: Buffer.from(html),
+			mimeType: "text/html",
+			fileName: `${fileName}.html`,
+		};
+	}
+
+	private async exportToPdf(content: string, fileName: string): Promise<ExportFileResponseDto> {
+		const html = this.markdown.render(content);
+		const options = { format: "A4" };
+		const file = { content: html };
+
+		const pdfBuffer = await htmlPdf.generatePdf(file, options);
+		return {
+			fileContent: pdfBuffer,
+			mimeType: "application/pdf",
+			fileName: `${fileName}.pdf`,
+		};
+	}
 }

backend/src/files/types/export-file.type.ts

@@ -0,0 +1,18 @@
+import { ApiProperty } from "@nestjs/swagger";
+
+export class ExportFileRequestBody {
+	@ApiProperty({ type: String, description: "export_type" })
+	exportType: "pdf" | "html" | "markdown";
+
+	@ApiProperty({ type: String, description: "markdown string" })
+	content: string;
+
+	@ApiProperty({ type: String, description: "File name" })
+	fileName: string;
+}
+
+export interface ExportFileResponseDto {
+	fileContent: Buffer;
+	mimeType: string;
+	fileName: string;
+}