This repo is for version-controlling the API/Lambda functions that control the Plantly backend.
These lambda functions are all deployed manually, this repo simply serves as a repository for the latest version
Plantly uses a micro-service architecture so the functions here belong to different micro-services and different APIs.
- IoT API - Bridge the MQTT communication between the raspberry pi and our AWS cloud
- Elasticsearch API - Fetch and write data to elasticsearch indexes (one index per user)
- getMyDevices API - Fetch and write device data to DynamoDB
- getUserData API - Fetch and write user Data to DynamoDB
- linkDevice - Standalone lambda function to link a device to a user ID
- getPrediction API - Websocket API for fetching model prediction data
- registerDevice - Standalone lambda function to register a device
- registerToDynamoDB - Link device to account on DynamoDB
- uploadAvatar - Update a user avatar on the front-end
An AWS Account and an API Gateway API route to call a function, you will also need an IAM role with appropriate privileges to execute Lambda functions and also save logs to Cloudwatch
https://docs.aws.amazon.com/lambda/latest/dg/services-apigateway.html
The deployment is a manual process, as the entire backend is a serverless, and performs its logic through triggers of rules set by IoT Core & API Gateway
To deploy a Lambda function simply clone or copy the code to a zip file and upload to the AWS Lambda cloud console, to the matching function name
Summary:
-
To deploy prexisting functions, copy the function, to the relevant function in the AWS Lambda Function Console.
-
Check that the triggers have been attached (check for APIGateway Links)
Summary of API Gateway Set Up:
- From the Actions dropdown menu, choose Create Method.
- Under the resource name > you'll see a dropdown menu.
- Choose GET/POST, or in the case of websocket create a new route.
-
Integration type, choose Lambda Function to enable Lambdy proxy integration. Make sure region is selected as ap-southeast-2 and enter the name of the function.
-
When the Add Permission to Lambda Function popup appears (saying "You are about to give API Gateway permission to invoke your Lambda function…"), choose OK to grant API Gateway that permission.
If you have issues look at the latest develop guide instructions from AWS: https://docs.aws.amazon.com/apigateway/latest/developerguide/getting-started.html
Summary:
- To deploy prexisting functions, copy the function, to the relevant function in the AWS Lambda Function Console.
- Check that the triggers have been attached
Summary Deploy:
- Go to the AWS Lambda Function Console, and create a function
- Add a trigger, and select 'IoT Core Rules'
- Add in the relevant SQL Statement to allow for a trigger from a topic
Take a look at this thorough documentation from AWS, to follow the implementation and set up of the AWSLambda functions to IotCore https://docs.aws.amazon.com/iot/latest/developerguide/iot-lambda-rule.html
Lambda functions are tested using AWS Cloudwatch. Make sure you enable logging when you create an API. In the API Gateway console, find the Logs/Tracing option under Stage Editor pane for the API and enable Cloudwatch Logs. You will find each APi has its own "Log Group" and inside each Log Group are logs for a particular function called by a route.
However you can also do manual testing with either Postman or wscat.
In postman enter the endpoint URL of a request in the address bar and choose the appropriate HTTP method from the drop-down.
In the authorization tab choose AWS Signature for the authorization Type. Enter your AWS IAM user's access key ID in the AccessKey input field. Enter your IAM user secret key in SecretKey.
Alterntively you can use a Lambda token.
Specify an appropriate AWS region that matches the region specified in the invocation URL. Enter execute-api in Service Name.
Choose the Headers tab. Optionally, delete any existing headers. This can clear any stale settings that may cause errors. Add any required custom headers. For example, if API keys are enabled, you can set the x-api-key:{api_key} name/value pair here.
Choose Send to submit the request and receive a response. You can check this response in Cloudwatch.
Download wscat from https://www.npmjs.com/package/wscat
or install wscat by running the following command:
npm install -g wscat
To connect to your API, run the wscat command as shown in the following example.
wscat -c wss://rumb30qq13.execute-api.ap-southeast-2.amazonaws.com/default
Then you can send a json request like so:
{"device":"c0cb03a49a754a17b07b85c4d4f19039", "username": "test"}
And you should get something back such as:
{"pi-id": "c0cb03a49a754a17b07b85c4d4f19039", "prediction": "low temp & low light", "type": "prediction", "time": "2020-06-14T09:36:16.209814"}
If you can configured your Cloudwatch correctly you will find a Log Group named something like /aws/apigateway/rumb30qq13/default
You can use this to check the invocation logs for output of your tests and general usage.
2020-06-14T16:51:32.505+10:00
(OGxWOFh2ywMFQsA=) WebSocket API [rumb30qq13] received message from client [OGxWNcuwywMCFpA=]. Message: [
{
"requestContext": {
"routeKey": "$default",
"messageId": "OGxWOcuxSwMCFpA=",
"eventType": "MESSAGE",
"extendedRequestId": "OGxWOFh2ywMFQsA=",
"requestTime": "14/Jun/2020:06:51:32 +0000",
"messageDirection": "IN",
"stage": "default",
"connectedAt": 1592117492425,
"requestTimeEpoch": 1592117492502,
"identity": {
"cognitoIdentityPoolId": null,
"cognitoIdentityId": null,
"principalOrgId": null,
"cognitoAuthenticationType": null,
"userArn": null,
"userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.97 Safari/537.36",
"accountId": null,
"caller": null,
"sourceIp": "220.253.123.231",
"accessKey": null,
"cognitoAuthenticationProvider": null,
"user": null
},
"requestId": "OGxWOFh2ywMFQsA=",
"domainName": "rumb30qq13.execute-api.ap-southeast-2.amazonaws.com",
"connectionId": "OGxWNcuwywMCFpA=",
"apiId": "rumb30qq13"
},
"body": "{ \"device\": \"test132452\", \"username\": \"test7\"}",
"isBase64Encoded": false
}