NestJS/SheetJS demo instructions

.npmignore

@@ -43,6 +43,7 @@ tmp
 .eslintignore
 .eslintrc
 .jshintrc
+xlsx.mini.js
 CONTRIBUTING.md
 Makefile
 make.cmd

demos/server/.gitignore

@@ -1 +1,2 @@
 xlsx.full.min.js
+xlsx-demo

demos/server/Makefile

@@ -19,3 +19,7 @@ koa: init ## koa demo
 hapi: init ## hapi demo
 	cp ../../dist/xlsx.full.min.js .
 	node hapi.js
+
+.PHONY: nest
+nest: init ## nest demo
+	bash -c ./nest.sh

demos/server/README.md

@@ -25,7 +25,7 @@ The following commands are required in order to test the [Koa](https://github.co
 ```bash
 npm install koa printj formidable xlsx
 node koa.js
-``` 
+```
 
 ### Hapi Setup
 
@@ -36,7 +36,7 @@ The following commands are required in order to test the [Hapi](https://github.c
 ```bash
 npm install hapi@16.x printj tiny-worker xlsx
 node hapi.js
-``` 
+```
 
 
 
@@ -163,4 +163,36 @@ curl -X POST http://localhost:7262/file?f=sheetjs.csv
 curl -X GET http://localhost:7262/?f=sheetjs.xlsb
 ```
 
+
+
+## NestJS
+
+[NestJS](https://nestjs.com/) is a Node.js framework for server-side web applications.
+
+This demo uses SheetJS to injest a spreadsheet via a POST API endpoint. The file
+arrive to the endpoint as body `form-data`, accessible using the `file` key.
+After parsing the file, CSV contents of the first worksheet will be returned.
+[Body parsing uses `multer`](https://docs.nestjs.com/techniques/file-upload).
+
+Before running the demo, the NestJS CLI tool must be installed.  The instruction
+is described in the NestJS ["First Steps"](https://docs.nestjs.com/first-steps):
+
+```bash
+npm i -g @nestjs/cli
+make nest
+```
+
+The demo can be tested using the `/sheetjs/upload-xlsx-file` endpoint:
+
+```bash
+curl -X POST -F "file=@test.xlsx" http://localhost:3000/sheetjs/upload-xlsx-file
+```
+
+The included [`nest.sh`](./nest.sh) script creates and configures the project.
+
+
+This demo creates a module and a controller.  The controller handles the actual
+requests (creating the endpoint) while the module is used to configure `multer`.
+
+
 [![Analytics](https://ga-beacon.appspot.com/UA-36810333-1/SheetJS/js-xlsx?pixel)](https://github.com/SheetJS/js-xlsx)

demos/server/nest.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# it is assumed that @nestjs/cli is installed globally
+
+if [ ! -e xlsx-demo ]; then
+	nest new -p npm xlsx-demo
+fi
+
+cd xlsx-demo
+npm i --save xlsx
+npm i --save-dev @types/multer
+
+if [ ! -e src/sheetjs/sheetjs.module.ts ]; then
+	nest generate module sheetjs
+fi
+
+if [ ! -e src/sheetjs/sheetjs.controller.ts ]; then
+	nest generate controller sheetjs
+fi
+
+cp ../sheetjs.module.ts src/sheetjs/
+cp ../sheetjs.controller.ts src/sheetjs/
+mkdir -p upload
+npm run start

demos/server/sheetjs.controller.ts

@@ -0,0 +1,19 @@
+import { Controller, Logger, Post, UploadedFile, UseInterceptors } from '@nestjs/common';
+import { FileInterceptor } from '@nestjs/platform-express';
+import { readFile, utils } from 'xlsx';
+
+@Controller('sheetjs')
+export class SheetjsController {
+  private readonly logger = new Logger(SheetjsController.name);
+
+  @Post('upload-xlsx-file')
+  @UseInterceptors(FileInterceptor('file'))
+  async uploadXlsxFile(@UploadedFile() file: Express.Multer.File) {
+    // Open the uploaded XLSX file and perform SheetJS operations
+    const workbook = readFile(file.path);
+    const firstSheet = workbook.Sheets[workbook.SheetNames[0]];
+    const output = utils.sheet_to_csv(firstSheet);
+    this.logger.log(output);
+    return output;
+  }
+}

demos/server/sheetjs.module.ts

@@ -0,0 +1,13 @@
+import { Module } from '@nestjs/common';
+import { SheetjsController } from './sheetjs.controller';
+import { MulterModule } from '@nestjs/platform-express';
+
+@Module({
+  controllers: [SheetjsController],
+  imports: [
+    MulterModule.register({
+      dest: './upload',
+    }),
+  ],
+})
+export class SheetjsModule {}