✨ Add AWS DynamoDB node (#1602)

* dynamodb: request item

* dynamodb: query database

* dynamodb: scans table

* dynamodb: typehints in decodeItem

* dynamodb: recursively decodes map and lists

* dynamodb: cleanup interface, using additional-fields collection

* dynamodb: using fixedCollection for ExpressionAttributeValues

* dynamodb: converts spaces to tabs

* dynamodb: scans with FilterExpression

* dynamodb: fixes tslint

* ⚡ Refactor node

* 🔨 Refactor into separate dir

* ⚡ Add table name loader

* ✏️ Update operation descriptions

* ⚡ Add partition key name param to delete

* ⚡ Add params to get operation

* 🔨 Refactor get operation per feedback

* ⚡ Refactor for consistency

* ⚡ Add createUpdate operation

* aja

* asasa

* aja

* aja

* aja

* ⚡ Improvements

* ⚡ Lint node

* ⚡ Lint description

* 🔥 Remove unused option

* ⚡ Apply David's feedback

* ✏️ Add descriptions for specific attributes

* 🔨 Rename return values

* Implement define and automap

* ⚡ Minior changes

Co-authored-by: Michael Hirschler <michael.vhirsch@gmail.com>
Co-authored-by: ricardo <ricardoespinoza105@gmail.com>
Co-authored-by: Jan Oberhauser <jan.oberhauser@gmail.com>

packages/nodes-base/nodes/Aws/DynamoDB/GenericFunctions.ts

@@ -0,0 +1,108 @@
+import {
+	URL,
+} from 'url';
+
+import {
+	sign,
+} from 'aws4';
+
+import {
+	IExecuteFunctions,
+	IHookFunctions,
+	ILoadOptionsFunctions,
+	IWebhookFunctions,
+} from 'n8n-core';
+
+import {
+	ICredentialDataDecryptedObject,
+	IDataObject,
+	INodeExecutionData,
+} from 'n8n-workflow';
+
+import {
+	IRequestBody,
+} from './types';
+
+function getEndpointForService(service: string, credentials: ICredentialDataDecryptedObject): string {
+	let endpoint;
+	if (service === 'lambda' && credentials.lambdaEndpoint) {
+		endpoint = credentials.lambdaEndpoint;
+	} else if (service === 'sns' && credentials.snsEndpoint) {
+		endpoint = credentials.snsEndpoint;
+	} else {
+		endpoint = `https://${service}.${credentials.region}.amazonaws.com`;
+	}
+	return (endpoint as string).replace('{region}', credentials.region as string);
+}
+
+export async function awsApiRequest(this: IHookFunctions | IExecuteFunctions | ILoadOptionsFunctions | IWebhookFunctions, service: string, method: string, path: string, body?: object | IRequestBody, headers?: object): Promise<any> { // tslint:disable-line:no-any
+	const credentials = this.getCredentials('aws');
+	if (credentials === undefined) {
+		throw new Error('No credentials got returned!');
+	}
+
+	// Concatenate path and instantiate URL object so it parses correctly query strings
+	const endpoint = new URL(getEndpointForService(service, credentials) + path);
+
+	const options = sign({
+		uri: endpoint,
+		service,
+		region: credentials.region,
+		method,
+		path: '/',
+		headers: { ...headers },
+		body: JSON.stringify(body),
+	}, {
+		accessKeyId: credentials.accessKeyId,
+		secretAccessKey: credentials.secretAccessKey,
+	});
+
+	try {
+		return JSON.parse(await this.helpers.request!(options));
+	} catch (error) {
+		const errorMessage = (error.response && error.response.body.message) || (error.response && error.response.body.Message) || error.message;
+		if (error.statusCode === 403) {
+			if (errorMessage === 'The security token included in the request is invalid.') {
+				throw new Error('The AWS credentials are not valid!');
+			} else if (errorMessage.startsWith('The request signature we calculated does not match the signature you provided')) {
+				throw new Error('The AWS credentials are not valid!');
+			}
+		}
+
+		throw new Error(`AWS error response [${error.statusCode}]: ${errorMessage}`);
+	}
+}
+
+
+export async function awsApiRequestAllItems(this: IHookFunctions | IExecuteFunctions | ILoadOptionsFunctions | IWebhookFunctions, service: string, method: string, path: string, body?: IRequestBody, headers?: object): Promise<any> { // tslint:disable-line:no-any
+
+	const returnData: IDataObject[] = [];
+
+	let responseData;
+
+	do {
+		responseData = await awsApiRequest.call(this, service, method, path, body, headers);
+		if (responseData.LastEvaluatedKey) {
+			body!.ExclusiveStartKey = responseData.LastEvaluatedKey;
+		}
+		returnData.push(...responseData.Items);
+	} while (
+		responseData.LastEvaluatedKey !== undefined
+	);
+
+	return returnData;
+}
+
+export function copyInputItem(item: INodeExecutionData, properties: string[]): IDataObject {
+	// Prepare the data to insert and copy it to be returned
+	let newItem: IDataObject;
+	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;
+}