feat(Spreadsheet File Node): Improve CSV parsing (#7448)

This adds support for
1. custom delimiters
2. reading offsets to avoid having to read a large CSV all at once
3. excluding byte-order-mark

NODE-861
#7443

packages/nodes-base/nodes/SpreadsheetFile/description.ts

@@ -201,6 +201,59 @@ export const optionsProperties: INodeProperties[] = [
 				default: true,
 				description: 'Whether the first row of the file contains the header names',
 			},
+			{
+				displayName: 'Delimiter',
+				name: 'delimiter',
+				type: 'string',
+				displayOptions: {
+					show: {
+						'/operation': ['fromFile'],
+						'/fileFormat': ['csv'],
+					},
+				},
+				default: ',',
+				description: 'Set the field delimiter',
+			},
+			{
+				displayName: 'Starting Line',
+				name: 'fromLine',
+				type: 'number',
+				displayOptions: {
+					show: {
+						'/operation': ['fromFile'],
+						'/fileFormat': ['csv'],
+					},
+				},
+				default: 0,
+				description: 'Start handling records from the requested line number',
+			},
+			{
+				displayName: 'Max Number of Rows to Load',
+				name: 'maxRowCount',
+				type: 'number',
+				displayOptions: {
+					show: {
+						'/operation': ['fromFile'],
+						'/fileFormat': ['csv'],
+					},
+				},
+				default: -1,
+				description: 'Stop handling records after the requested number of rows are read',
+			},
+			{
+				displayName: 'Exclude Byte Order Mark (BOM)',
+				name: 'enableBOM',
+				type: 'boolean',
+				displayOptions: {
+					show: {
+						'/operation': ['fromFile'],
+						'/fileFormat': ['csv'],
+					},
+				},
+				default: false,
+				description:
+					'Whether to detect and exclude the byte-order-mark from the CSV Input if present',
+			},
 			{
 				displayName: 'Include Empty Cells',
 				name: 'includeEmptyCells',

packages/nodes-base/nodes/SpreadsheetFile/test/SpreadsheetFile.test.ts

@@ -1,24 +1,28 @@
+import path from 'path';
+import type { IWorkflowBase } from 'n8n-workflow';
 import * as Helpers from '@test/nodes/Helpers';
 import type { WorkflowTestData } from '@test/nodes/types';
-
 import { executeWorkflow } from '@test/nodes/ExecuteWorkflow';
-import path from 'path';
 
 describe('Execute Spreadsheet File Node', () => {
 	beforeEach(async () => {
 		await Helpers.initBinaryDataService();
 	});
 
-	// replace workflow json 'Read Binary File' node's filePath to local file
-	const workflow = Helpers.readJsonFileSync('nodes/SpreadsheetFile/test/workflow.json');
-	const node = workflow.nodes.find((n: any) => n.name === 'Read Binary File');
-	node.parameters.filePath = path.join(__dirname, 'spreadsheet.csv');
+	const loadWorkflow = (fileName: string, csvName: string) => {
+		const workflow = Helpers.readJsonFileSync<IWorkflowBase>(
+			`nodes/SpreadsheetFile/test/${fileName}`,
+		);
+		const node = workflow.nodes.find((n) => n.name === 'Read Binary File');
+		node!.parameters.fileSelector = path.join(__dirname, csvName);
+		return workflow;
+	};
 
 	const tests: WorkflowTestData[] = [
 		{
 			description: 'execute workflow.json',
 			input: {
-				workflowData: workflow,
+				workflowData: loadWorkflow('workflow.json', 'spreadsheet.csv'),
 			},
 			output: {
 				nodeData: {
@@ -78,6 +82,7 @@ describe('Execute Spreadsheet File Node', () => {
 							},
 						],
 					],
+					'Read CSV with Row Limit': [[{ json: { A: '1', B: '2', C: '3' } }]],
 					'Write To File CSV': [
 						[
 							{
@@ -149,6 +154,18 @@ describe('Execute Spreadsheet File Node', () => {
 				},
 			},
 		},
+		{
+			description: 'execute workflow.bom.json',
+			input: {
+				workflowData: loadWorkflow('workflow.bom.json', 'bom.csv'),
+			},
+			output: {
+				nodeData: {
+					'Edit with BOM included': [[{ json: { X: null } }]],
+					'Edit with BOM excluded': [[{ json: { X: '1' } }]],
+				},
+			},
+		},
 	];
 
 	const nodeTypes = Helpers.setup(tests);

packages/nodes-base/nodes/SpreadsheetFile/test/bom.csv

@@ -0,0 +1,2 @@
+a,b,c
+1,2,3

packages/nodes-base/nodes/SpreadsheetFile/test/workflow.bom.json

@@ -0,0 +1,155 @@
+{
+  "nodes": [
+    {
+      "parameters": {},
+      "id": "40bf604f-19f9-43e7-8bbb-74c36925f154",
+      "name": "When clicking \"Execute Workflow\"",
+      "type": "n8n-nodes-base.manualTrigger",
+      "typeVersion": 1,
+      "position": [
+        -320,
+        1040
+      ]
+    },
+    {
+      "parameters": {
+        "fileSelector": "bom.csv"
+      },
+      "id": "623ea890-8882-4273-973e-834652d823b5",
+      "name": "Read Binary File",
+      "type": "n8n-nodes-base.readBinaryFiles",
+      "typeVersion": 1,
+      "position": [
+        -100,
+        1040
+      ]
+    },
+    {
+      "parameters": {
+        "fileFormat": "csv",
+        "options": {
+          "enableBOM": true
+        }
+      },
+      "id": "c8cca5fb-e119-4ca1-a597-4f051a7f64ea",
+      "name": "Exclude BOM",
+      "type": "n8n-nodes-base.spreadsheetFile",
+      "typeVersion": 2,
+      "position": [
+        120,
+        960
+      ]
+    },
+    {
+      "parameters": {
+        "fileFormat": "csv",
+        "options": {
+          "enableBOM": false
+        }
+      },
+      "id": "56ec11dc-966b-4d06-b8c0-61475b30333d",
+      "name": "Include BOM",
+      "type": "n8n-nodes-base.spreadsheetFile",
+      "typeVersion": 2,
+      "position": [
+        120,
+        1180
+      ]
+    },
+    {
+      "parameters": {
+        "fields": {
+          "values": [
+            {
+              "name": "X",
+              "stringValue": "={{ $json.a }}"
+            }
+          ]
+        },
+        "include": "none",
+        "options": {}
+      },
+      "id": "6f6bccf2-d674-4774-9df9-6f6fd893bace",
+      "name": "Edit with BOM excluded",
+      "type": "n8n-nodes-base.set",
+      "typeVersion": 3.2,
+      "position": [
+        320,
+        960
+      ]
+    },
+    {
+      "parameters": {
+        "fields": {
+          "values": [
+            {
+              "name": "X",
+              "stringValue": "={{ $json.a }}"
+            }
+          ]
+        },
+        "include": "none",
+        "options": {}
+      },
+      "id": "27ca5cde-19cb-4bf2-9ab4-7f7e77ad01bd",
+      "name": "Edit with BOM included",
+      "type": "n8n-nodes-base.set",
+      "typeVersion": 3.2,
+      "position": [
+        320,
+        1180
+      ]
+    }
+  ],
+  "connections": {
+    "When clicking \"Execute Workflow\"": {
+      "main": [
+        [
+          {
+            "node": "Read Binary File",
+            "type": "main",
+            "index": 0
+          }
+        ]
+      ]
+    },
+    "Exclude BOM": {
+      "main": [
+        [
+          {
+            "node": "Edit with BOM excluded",
+            "type": "main",
+            "index": 0
+          }
+        ]
+      ]
+    },
+    "Include BOM": {
+      "main": [
+        [
+          {
+            "node": "Edit with BOM included",
+            "type": "main",
+            "index": 0
+          }
+        ]
+      ]
+    },
+    "Read Binary File": {
+      "main": [
+        [
+          {
+            "node": "Exclude BOM",
+            "type": "main",
+            "index": 0
+          },
+          {
+            "node": "Include BOM",
+            "type": "main",
+            "index": 0
+          }
+        ]
+      ]
+    }
+  }
+}

packages/nodes-base/nodes/SpreadsheetFile/test/workflow.json

@@ -1,7 +1,4 @@
 {
-	"meta": {
-		"instanceId": "104a4d08d8897b8bdeb38aaca515021075e0bd8544c983c2bb8c86e6a8e6081c"
-	},
 	"nodes": [
 		{
 			"parameters": {},
@@ -29,11 +26,11 @@
 		},
 		{
 			"parameters": {
-				"filePath": "C:\\Users\\spech\\Documents\\GitHub\\n8n-master\\packages\\nodes-base\\nodes\\SpreadsheetFile\\test\\spreadsheet.csv"
+				"fileSelector": "spreadsheet.csv"
 			},
 			"id": "d7620053-eb3d-43dd-b2cd-d60d9a08a9cc",
 			"name": "Read Binary File",
-			"type": "n8n-nodes-base.readBinaryFile",
+			"type": "n8n-nodes-base.readBinaryFiles",
 			"typeVersion": 1,
 			"position": [
 				840,
@@ -173,6 +170,22 @@
 				1060,
 				940
 			]
+		},
+		{
+			"parameters": {
+				"fileFormat": "csv",
+				"options": {
+					"maxRowCount": 1
+				}
+			},
+			"id": "de905389-a11b-4dd8-8416-14d650804445",
+			"name": "Read CSV with Row Limit",
+			"type": "n8n-nodes-base.spreadsheetFile",
+			"typeVersion": 2,
+			"position": [
+				-60,
+				1340
+			]
 		}
 	],
 	"connections": {
@@ -245,9 +258,14 @@
 						"node": "Read From File Read as String",
 						"type": "main",
 						"index": 0
+					},
+					{
+						"node": "Read CSV with Row Limit",
+						"type": "main",
+						"index": 0
 					}
 				]
 			]
 		}
 	}
-}
+}

packages/nodes-base/nodes/SpreadsheetFile/v2/SpreadsheetFileV2.node.ts

@@ -1,5 +1,4 @@
 /* eslint-disable n8n-nodes-base/node-filename-against-convention */
-import { pipeline } from 'stream/promises';
 import type {
 	IDataObject,
 	IExecuteFunctions,
@@ -85,7 +84,12 @@ export class SpreadsheetFileV2 implements INodeType {
 					}
 
 					if (fileFormat === 'csv') {
+						const maxRowCount = options.maxRowCount as number;
 						const parser = createCSVParser({
+							delimiter: options.delimiter as string,
+							fromLine: options.fromLine as number,
+							bom: options.enableBOM as boolean,
+							to: maxRowCount > -1 ? maxRowCount : undefined,
 							columns: options.headerRow !== false,
 							onRecord: (record) => {
 								rows.push(record);
@@ -93,9 +97,18 @@ export class SpreadsheetFileV2 implements INodeType {
 						});
 						if (binaryData.id) {
 							const stream = await this.helpers.getBinaryStream(binaryData.id);
-							await pipeline(stream, parser);
+							await new Promise<void>(async (resolve, reject) => {
+								parser.on('error', reject);
+								parser.on('readable', () => {
+									stream.unpipe(parser);
+									stream.destroy();
+									resolve();
+								});
+								stream.pipe(parser);
+							});
 						} else {
 							parser.write(binaryData.data, BINARY_ENCODING);
+							parser.end();
 						}
 					} else {
 						let workbook: WorkBook;