🎨 Extract postgres functionality (#737)

* 🎉 executeQuery function extracted

* 🚧 add prettierrc to gitignore

* 🚧 insert function extracted

* ⚡ extract update function

* 💡 fix function docs

* 💡 add in code documentation

* 🎨 fix format

* 🎨 fix format

.gitignore

@@ -12,3 +12,4 @@ _START_PACKAGE
 .env
 .vscode
 .idea
+.prettierrc.js

packages/nodes-base/nodes/Postgres/Postgres.node.functions.ts

@@ -0,0 +1,129 @@
+import { IDataObject, INodeExecutionData } from 'n8n-workflow';
+import pgPromise = require('pg-promise');
+import pg = require('pg-promise/typescript/pg-subset');
+
+/**
+ * Returns of copy of the items which only contains the json data and
+ * of that only the define properties
+ *
+ * @param {INodeExecutionData[]} items The items to copy
+ * @param {string[]} properties The properties it should include
+ * @returns
+ */
+function getItemCopy(items: INodeExecutionData[], properties: string[]): IDataObject[] {
+	// Prepare the data to insert and copy it to be returned
+	let newItem: IDataObject;
+	return items.map(item => {
+		newItem = {};
+		for (const property of properties) {
+			if (item.json[property] === undefined) {
+				newItem[property] = null;
+			} else {
+				newItem[property] = JSON.parse(JSON.stringify(item.json[property]));
+			}
+		}
+		return newItem;
+	});
+}
+
+/**
+ * Executes the given SQL query on the database.
+ *
+ * @param {Function} getNodeParam The getter for the Node's parameters
+ * @param {pgPromise.IMain<{}, pg.IClient>} pgp The pgPromise instance
+ * @param {pgPromise.IDatabase<{}, pg.IClient>} db The pgPromise database connection
+ * @param {input[]} input The Node's input data
+ * @returns Promise<Array<object>>
+ */
+export function pgQuery(
+	getNodeParam: Function,
+	pgp: pgPromise.IMain<{}, pg.IClient>,
+	db: pgPromise.IDatabase<{}, pg.IClient>,
+	input: INodeExecutionData[],
+): Promise<Array<object>> {
+	const queries: string[] = [];
+	for (let i = 0; i < input.length; i++) {
+		queries.push(getNodeParam('query', i) as string);
+	}
+
+	return db.any(pgp.helpers.concat(queries));
+}
+
+/**
+ * Inserts the given items into the database.
+ *
+ * @param {Function} getNodeParam The getter for the Node's parameters
+ * @param {pgPromise.IMain<{}, pg.IClient>} pgp The pgPromise instance
+ * @param {pgPromise.IDatabase<{}, pg.IClient>} db The pgPromise database connection
+ * @param {INodeExecutionData[]} items The items to be inserted
+ * @returns Promise<Array<IDataObject>>
+ */
+export async function pgInsert(
+	getNodeParam: Function,
+	pgp: pgPromise.IMain<{}, pg.IClient>,
+	db: pgPromise.IDatabase<{}, pg.IClient>,
+	items: INodeExecutionData[],
+): Promise<Array<IDataObject[]>> {
+	const table = getNodeParam('table', 0) as string;
+	const schema = getNodeParam('schema', 0) as string;
+	let returnFields = (getNodeParam('returnFields', 0) as string).split(',') as string[];
+	const columnString = getNodeParam('columns', 0) as string;
+	const columns = columnString.split(',').map(column => column.trim());
+
+	const cs = new pgp.helpers.ColumnSet(columns);
+
+	const te = new pgp.helpers.TableName({ table, schema });
+
+	// Prepare the data to insert and copy it to be returned
+	const insertItems = getItemCopy(items, columns);
+
+	// Generate the multi-row insert query and return the id of new row
+	returnFields = returnFields.map(value => value.trim()).filter(value => !!value);
+	const query =
+		pgp.helpers.insert(insertItems, cs, te) +
+		(returnFields.length ? ` RETURNING ${returnFields.join(',')}` : '');
+
+	// Executing the query to insert the data
+	const insertData = await db.manyOrNone(query);
+
+	return [insertData, insertItems];
+}
+
+/**
+ * Updates the given items in the database.
+ *
+ * @param {Function} getNodeParam The getter for the Node's parameters
+ * @param {pgPromise.IMain<{}, pg.IClient>} pgp The pgPromise instance
+ * @param {pgPromise.IDatabase<{}, pg.IClient>} db The pgPromise database connection
+ * @param {INodeExecutionData[]} items The items to be updated
+ * @returns Promise<Array<IDataObject>>
+ */
+export async function pgUpdate(
+	getNodeParam: Function,
+	pgp: pgPromise.IMain<{}, pg.IClient>,
+	db: pgPromise.IDatabase<{}, pg.IClient>,
+	items: INodeExecutionData[],
+): Promise<Array<IDataObject>> {
+	const table = getNodeParam('table', 0) as string;
+	const updateKey = getNodeParam('updateKey', 0) as string;
+	const columnString = getNodeParam('columns', 0) as string;
+
+	const columns = columnString.split(',').map(column => column.trim());
+
+	// Make sure that the updateKey does also get queried
+	if (!columns.includes(updateKey)) {
+		columns.unshift(updateKey);
+	}
+
+	// Prepare the data to update and copy it to be returned
+	const updateItems = getItemCopy(items, columns);
+
+	// Generate the multi-row update query
+	const query =
+		pgp.helpers.update(updateItems, columns, table) + ' WHERE v.' + updateKey + ' = t.' + updateKey;
+
+	// Executing the query to update the data
+	await db.none(query);
+
+	return updateItems;
+}

packages/nodes-base/nodes/Postgres/Postgres.node.ts

@@ -3,36 +3,12 @@ import {
 	IDataObject,
 	INodeExecutionData,
 	INodeType,
-	INodeTypeDescription,
+	INodeTypeDescription
 } from 'n8n-workflow';
 
 import * as pgPromise from 'pg-promise';
 
-
+import { pgInsert, pgQuery, pgUpdate } from './Postgres.node.functions';
-/**
- * Returns of copy of the items which only contains the json data and
- * of that only the define properties
- *
- * @param {INodeExecutionData[]} items The items to copy
- * @param {string[]} properties The properties it should include
- * @returns
- */
-function getItemCopy(items: INodeExecutionData[], properties: string[]): IDataObject[] {
-	// Prepare the data to insert and copy it to be returned
-	let newItem: IDataObject;
-	return items.map((item) => {
-		newItem = {};
-		for (const property of properties) {
-			if (item.json[property] === undefined) {
-				newItem[property] = null;
-			} else {
-				newItem[property] = JSON.parse(JSON.stringify(item.json[property]));
-			}
-		}
-		return newItem;
-	});
-}
-
 
 export class Postgres implements INodeType {
 	description: INodeTypeDescription = {
@@ -52,7 +28,7 @@ export class Postgres implements INodeType {
 			{
 				name: 'postgres',
 				required: true,
-			}
+			},
 		],
 		properties: [
 			{
@@ -103,7 +79,6 @@ export class Postgres implements INodeType {
 				description: 'The SQL query to execute.',
 			},
 
-
 			// ----------------------------------
 			//         insert
 			// ----------------------------------
@@ -143,9 +118,7 @@ export class Postgres implements INodeType {
 				type: 'string',
 				displayOptions: {
 					show: {
-						operation: [
+						operation: ['insert'],
-							'insert'
-						],
 					},
 				},
 				default: '',
@@ -167,7 +140,6 @@ export class Postgres implements INodeType {
 				description: 'Comma separated list of the fields that the operation will return',
 			},
 
-
 			// ----------------------------------
 			//         update
 			// ----------------------------------
@@ -216,13 +188,10 @@ export class Postgres implements INodeType {
 				placeholder: 'name,description',
 				description: 'Comma separated list of the properties which should used as columns for rows to update.',
 			},
-
+		],
-		]
 	};
 
-
 	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
-
 		const credentials = this.getCredentials('postgres');
 
 		if (credentials === undefined) {
@@ -253,39 +222,15 @@ export class Postgres implements INodeType {
 			//         executeQuery
 			// ----------------------------------
 
-			const queries: string[] = [];
+			const queryResult = await pgQuery(this.getNodeParameter, pgp, db, items);
-			for (let i = 0; i < items.length; i++) {
-				queries.push(this.getNodeParameter('query', i) as string);
-			}
-
-			const queryResult = await db.any(pgp.helpers.concat(queries));
 
 			returnItems = this.helpers.returnJsonArray(queryResult as IDataObject[]);
-
 		} else if (operation === 'insert') {
 			// ----------------------------------
 			//         insert
 			// ----------------------------------
 
-			const table = this.getNodeParameter('table', 0) as string;
+			const [insertData, insertItems] = await pgInsert(this.getNodeParameter, pgp, db, items);
-			const schema = this.getNodeParameter('schema', 0) as string;
-			let returnFields = (this.getNodeParameter('returnFields', 0) as string).split(',') as string[];
-			const columnString = this.getNodeParameter('columns', 0) as string;
-			const columns = columnString.split(',').map(column => column.trim());
-
-			const cs = new pgp.helpers.ColumnSet(columns);
-
-			const te = new pgp.helpers.TableName({ table, schema });
-
-			// Prepare the data to insert and copy it to be returned
-			const insertItems = getItemCopy(items, columns);
-
-			// Generate the multi-row insert query and return the id of new row
-			returnFields = returnFields.map(value => value.trim()).filter(value => !!value);
-			const query = pgp.helpers.insert(insertItems, cs, te) + (returnFields.length ?  ` RETURNING ${returnFields.join(',')}` : '');
-
-			// Executing the query to insert the data
-			const insertData = await db.manyOrNone(query);
 
 			// Add the id to the data
 			for (let i = 0; i < insertData.length; i++) {
@@ -293,37 +238,17 @@ export class Postgres implements INodeType {
 					json: {
 						...insertData[i],
 						...insertItems[i],
-					}
+					},
 				});
 			}
-
 		} else if (operation === 'update') {
 			// ----------------------------------
 			//         update
 			// ----------------------------------
 
-			const table = this.getNodeParameter('table', 0) as string;
+			const updateItems = await pgUpdate(this.getNodeParameter, pgp, db, items);
-			const updateKey = this.getNodeParameter('updateKey', 0) as string;
-			const columnString = this.getNodeParameter('columns', 0) as string;
-
-			const columns = columnString.split(',').map(column => column.trim());
-
-			// Make sure that the updateKey does also get queried
-			if (!columns.includes(updateKey)) {
-				columns.unshift(updateKey);
-			}
-
-			// Prepare the data to update and copy it to be returned
-			const updateItems = getItemCopy(items, columns);
-
-			// Generate the multi-row update query
-			const query = pgp.helpers.update(updateItems, columns, table) + ' WHERE v.' + updateKey + ' = t.' + updateKey;
-
-			// Executing the query to update the data
-			await db.none(query);
-
-			returnItems = this.helpers.returnJsonArray(updateItems	 as IDataObject[]);
 
+			returnItems = this.helpers.returnJsonArray(updateItems);
 		} else {
 			await pgp.end();
 			throw new Error(`The operation "${operation}" is not supported!`);