I've recently signed up to AWS to test out their IoT platform and after setting up a few Things and going through the documentation I still seem to be missing a crucial bit of information - how to wrangle all the information from my Things?
For example if I were to build a web-based application to display the health/status of all the Things and possibly also interact with a specific Thing, what would be the way to go about it?
Do I register a "dummy" thing that also uses the device SDK to pub/sub to the topics?
Do I take whatever data the Things publish and route it to a shared DB for further processing?
Do I create Lambdas that the Things invoke?
Do I create a stand-alone application that uses the general AWS SDK to connect itself to the IoT platform?
To me the last idea sounds the most viable and "preferred" as I would need two-way interaction, not just passive listening to changes in Things, is that correct?
Generally speaking your setup might be:
IoT device publishes to AWS SQS
Some Service (application or lambda) reads from SQS and processes data (e.g. saves it to DynamoDB)
And then to display data
Stand alone application reads from DynamoDB and makes data available to users
There are lots of permutations of this. For example your IoT device can write directly to DynamoDB, then you can process the data from there. I would suggest a better pattern is to write to SQS, as you will have a clean separation between data publishing, processing and storage.
In the first instance I would probably write one application that reads from the SQS, processes the data, stores it in DynamoDB and then provides access to that data for users. A better solution longer term is to have separate systems to process/store the data, and to present that data to users.
Lambda is popular for processing of the device data, as its cost effective (runs only when needed) and scales well. Your data presentation application is probably a traditional webapp running on something like elastic beanstalk.
Related
I've been learning more and more about AWS lately. I've been reading through the white papers and working my way through the various services. I've been working on PHP applications and front-end dev for a while now. Two things really stuck out to me. Those two things are server-less architecture using Lambdas with event-triggers and SQS (queues). The last three years I have been working with REST over HTTP with frameworks like Angular.
It occurred to me though that one could create an entire back-end/service layer through Lambda's and message queues alone. Perhaps I'm naive as I have never used that type of architecture for a real world project but it seems like a very simple means to build a service layer.
Has anyone built a web application back-end consisting of only Lambdas and message queues as opposed to "traditional" http request with REST. If so what types of drawbacks are there to this type of architecture besides relying so heavily on a vendor like AWS?
For example, wouldn't it be entirely possible to build a CMS using these technologies where the scripts create the AWS assets programmatically given a key with full admin rights to an account?
Yes, you can practically create the entire backend service using serverless architecture.
There are a lot of AWS services that usually play into the serverless gambit of things.
DynamoDB, SNS, SQS, S3 to name a few.
AWS Lambda is the backbone and sort of acts as a glue to bind these services.
Serverless doesn't mean you move away from "traditional" http request to message queues. If you need the web interface you would still need to use HTTP. You would primarily use message queues to decouple your services.
So, if you want the service to be accessible over HTTP just like your REST services and still be serverless then you can do that as well. And for that you will need to use AWS API Gateway in conjunction with AWS Lambda
One primary drawback/limitation is that debugging is not very straightforward. You cannot login to the system and cannot attach remote debuggers. And then obviously you get tied into the vendor.
Then there are limitations on the resources. E.g. Lambda can offer you a maximum memory footprint of 5GB, so if you need to do some compute intensive job that needs more memory and can't be broken down into sub tasks then serverless (AWS Lambda) is not an option for you.
my company has a messaging system which sends real-time messages in JSON format, and it's not built on AWS
our team is trying to use AWS SQS to receive these messages, which will then have DynamoDB to storage this messages
im thinking to use EC2 to read this messages then save them
any better solution ?? or how to do it i don't have a good experience
First of All EC2 is infrastructure on Cloud, It is similar to physical machine with OS on local setup. If you want to create any application that will fetch the data from Amazon SQS(Messages in Json Format) and Push it in dynamodb(No Sql database), Your design is correct as both SQS and DynamoDb have thorough Json Support. Once your application is ready then you deploy that application on EC2 machine.
For achieving this, your application must have the asyc Buffered SQS consumer that will consume the messages(limit of sqs messages is 256KB), Hence whichever application is publishing messages size of messages needs to be less thab 256Kb.
Please refer below link for sqs consumer
is putting sqs-consumer to detect receiveMessage event in sqs scalable
Once you had consumed the message from sqs queue you need to save it in dynamodb, that you can easily do it using crud repository. With Repository you can directly save the json in Dynamodb table but please sure to configure the provisioning write capacity based on requests, because more will be the provisioning capacity more will be the cost. Please refer below link for configuring the write capacity of table.
Dynamodb reading and writing units
In general, you'll have a setup something like this:
The EC2 instances (one or more) will read your queue every few seconds to see if there is anything there. If so, they will write this data to DynamoDB.
Based on what you're saying you'll have less than 1,000,000 reads from SQS in a month so you can start out on the free tier for that. You can have a single EC2 instance initially and that can be a very small instance - a T2.micro should be more than sufficient. And you don't need more than a few writes per second on DynamoDB.
The advantage of SQS is that if for some reason your EC2 instance is temporarily unavailable the messages continue to queue up and you won't lose any of them.
From a coding perspective, you don't mention your development environment but there are AWS libraries available for a pretty wide variety of environments. I develop in Java and the code to do this would be maybe 100 lines. I would guess that other languages would be similar. Make sure you look at long polling in the language you're using - it can help to speed up the processing and save you money.
If i understood the whole concept correctly, the "serverless" architecture assumes that instead of using own servers or containers, one should use bunch of aws services. Usually such architecture includes Amazon API Gateway, bunch of Lambda functions and DynamoDB (or alternative) for storing data and state, as Lambda can't keep state. And such services as EC2 is not participating in all this, well, because this is a virtual server and it diminish all the benefits of serverless architecture.
All this looks really cool, but i feel like i'm missing something important, because right now this seems to be not applicable for such cases as real time applications.
Say, i have 2 users online. One of them performs an action in an app, which triggers changes in database, which in turn, should trigger changes in the second user app.
The conventional way to send some data or command from server to client is websocket connection. But with serverless architecture there seem to be no way to establish and maintain websocket connection. So... where did i misunderstood the concept? Or, if i understood everything correctly, then how do i implement the interactions between 2 users as described above?
where did i misunderstood the concept?
Your observation is correct. It doesn't work out of the box using API Gateway and Lambda.
Applicable solution as described here is to use AWS IoT - yes, another AWS Service.
Serverless isn't just a matter of Lambda, API Gateway and DynamoDB, it's much bigger than that. One of the big advantages to Serverless is the operational burden that it takes off your plate. No more patching, no more capacity planning, no more config management. Those may seem trivial but doing those things well and across a significant fleet of instances is complex, expensive and time consuming. Another benefit is the economics. Public cloud leverages utility billing, meaning you pay for what you run whether or not you actually use it. With AWS most of the billing per service is by hour but with Lambda it's per 100ms. The cheapest EC2 instance running for a full month is about $10/m (double that for redundancy). $20 in Lambda pricing gets you millions of invocations so for most cases serverless is significantly cheaper.
Serverless isn't for everything though, it has it's limitations, for example it's not meant for running binaries. You can't run nginx in Lambda (for example), it's only meant to be a runtime environment for the programming languages that it supports. It's also specifically meant for event based workloads, which is perfect for microservice based architectures. Small independent discrete pieces of compute doing work that when done they send an event to another(s) to do something else and if needed return a response.
To address your concerns about realtime processing, depending on what your code is doing your Lambda function could complete in less than 100ms all the way up to 5 minutes. There are strategies to optimize it's duration time but in general it's for short lived work which is conducive of realtime scenarios.
In your example about the 2 users interacting with the web app and the db, that could very easily be built using serverless technologies with one or 2 functions and a DynamoDB table. The total roundtrip time could be as low as milliseconds if not seconds, it really all depends on your code and what it's doing. These would all be HTTP calls so no websockets needed. Think of a number of APIs calling each other and your Lambda code is the orchestrator.
You might want to look at SNS (simple notification service). In your example, if app user 2 is a a subscriber to an SNS topic, then when app user 1 makes a change that triggers an SNS message, it will be pushed to the subscriber (app user 2). The message can be pushed over several supported protocols (Amazon, Apple, Google, MS, Baidu) in addition to SMTP or SMS. The SNS message can be triggered by a lambda function or directly from a DynamoDB stream after an update (a database trigger). It's up to the app developer to select a message protocol and format. The app only has to receive messages through its native channels. This may not exactly be millisecond-latency 'real-time', but it's fast enough for all but the most latency-sensitive applications.
I've been working on an AWS serverless application for several months now, and am amazed at the variety of services available. The rate of improvement and new features being added is enough to leave you out-of-breath.
I'm working on a new game project at the moment that will consist of a React Native front-end and a Lambda-based back-end. The app requires some real time features such as active user records, geofencing, etc.
I was looking at Firebase's Realtime Database that looks like a really elegant solution for real-time data sync but I don't think AWS has anything quite like it.
The 3 options I could think of for "serverless" realtime using only AWS services are:
Option 1: AWS IoT Messaging over WebSockets
This one is quite obvious, a managed WebSockets connection through the IoT SDK. I was thinking of triggering Lambdas in response to inbound and outbound events and just use WebSockets as the realtime layer, building custom handling logic on the app client as you typically would.
The downside to this, at least compared to Firebase, is that I will have to handle the data in the events myself which will add another layer of management on top of WebSockets and will have to be standardized with the API data layer in the application's stores.
Pros:
Scalable bi-directional realtime connection
Cons:
Only works when the app is open
Message structure needs to be implemented
Multiple transport layers to be managed
Option 2: Push-triggered re-fetch
Another option is to use push notifications as real-time triggers but use a regular HTTP request to API Gateway to actually get the updated payload.
I like this approach because it sticks to only one transport layer and a single source of truth for application state. It will also trigger updates when the app is not open since these are Push Notifications.
The downside is that this is a lot of custom work with potentially difficult mappings between push notifications to the data that needs to be fetched.
Pros:
Push notifications work even when app is closed
Single source of truth, transport layer
Cons:
Most custom solution
Will involve many more HTTP requests overall
Option 3: Cognito Sync
This is newer to me and I'm not sure if it can actually be interfaced with from the server.
Cognito Sync offers user state sync. across devices complete with offline support and is part of the Cognito SDK which I'll be using anyway. It sounds like just what I'm looking for but couldn't find any conclusive evidence as to whether it is possible to modify, or "trigger", updates from AWS and not just from one of the devices.
Pros:
Provides an abstracted real-time data model
Connected to Cognito user records OOTB
Cons:
Not sure if can be modified or updated from Lambdas
I'm wondering if anyone has experience doing real-time on AWS as part of a Lambda-based architecture and if you have an opinion on what is the best way to proceed?
I asked a similar question to the AWS Support, and this was their response.
My question to them:
What's the group of AWS services (if it's possible) to give that same
in-browser real-time DBaaS feel like Firebase?
AWS Cognito seems to be great for user-accounts. Is there anything
similar for the WebSockets / real-time DB part?
Their response:
To your question, Firebase is closest to the AWS service AWS
MobileHub. You can check out more details below about mobilehub from
below link.
https://aws.amazon.com/mobile/details/
https://aws.amazon.com/mobile/getting-started/
"AWS Cognito seems to be great for user-accounts. Is there anything
similar for the WebSockets / real-time DB part?"
Amazon Dynamodb is a fast and flexible NoSQL database service for all
applications that need consistent, single-digit millisecond latency at
any scale. It is a fully managed cloud database and supports both
document and key-value store models. Its flexible data model, reliable
performance, and automatic scaling of throughput capacity, makes it a
great fit for mobile, web, gaming, ad tech, IoT, and many other
applications.
Amazon Dynamodb can be further optimized with Amazon DynamoDB
Accelerator (DAX) which is a fully managed, highly available,
in-memory cache that can reduce Amazon DynamoDB response times from
milliseconds to microseconds, even at millions of requests per second.
For more information, please see below documentation.
https://aws.amazon.com/dynamodb/getting-started/
https://aws.amazon.com/dynamodb/dax/
Should you have any further questions, please do not hesitate to let
me know.
Thanks.
Best regards,
Tayo O. Amazon Web Services
Check out the AWS Support Knowledge Center, a knowledge base of
articles and videos that answer customer questions about AWS services:
https://aws.amazon.com/premiumsupport/knowledge-center/?icmpid=support_email_category
Also while researching this answer I also found this, looks interesting:
https://aws.amazon.com/blogs/database/how-to-build-a-chat-application-with-amazon-elasticache-for-redis/
The comments to that article is interesting as well.
Jacob Wakeem:
What advantage this
approach have over using aws iot? It seems that iot has all these
functionality without writing a single line of code and with
server-less architecture.
Sam Dengler:
The managed PubSub feature in the AWS IoT
service is also a good approach to message-based applications, like
the one demonstrated in the article. With Elasticache (Redis),
customers who use Pub/Sub are typically also using Redis as a data
store for other use cases such as caching, leaderboards, etc. With
that said, you could also use ElastiCache (Redis) with the AWS IoT
service by triggering an AWS Lambda function via the AWS IoT rules
engine. Depending on how the message-based application is architected
and how the data is leveraged, one solution may be a better fit than
the other.
Check out AWS AppSync for some of these realtime and offline features using different data sources, including databases search and compute.
AWS Amplify is AWS's modern answer to Firebase.
Fastest way to build mobile and web applications
AWS Amplify is a development platform for building secure, scalable
mobile and web applications. It makes it easy for you to authenticate
users, securely store data and user metadata, authorize selective
access to data, integrate machine learning, analyze application
metrics, and execute server-side code. Amplify covers the complete
mobile application development workflow from version control, code
testing, to production deployment, and it easily scales with your
business from thousands of users to tens of millions. The Amplify
libraries and CLI, part of the Amplify Framework, are open source and
offer a pluggable interface that enables you to customize and create
your own plugins.
Sounds like AWS Serverless is most suited alternative.
Also wondering: AWS vs Firebase - Is It Even a Fair Fight?
AWS Amplify. You can find more information here: AWS Amplify
You could consider using supabase.
It is opensource and can be installed onto ec2 / docker containers.
https://supabase.com/docs/guides/hosting/docker
I've found the hosted solution / free really poewrful to get up and running quickly. (yet to deploy to aws)
I know this is an old question, but nowadays AWS offers AppSync... a service that destroys Firebase RDB in every aspect
I'm working on client-side SDK for my product (based on AWS). Workflow is as follows:
User of SDK somehow uploads data to some S3 bucket
User somehow saves command on some queue in SQS
One of the worker on EC2 polls the queue, executes operation and sends notification via SNS. This point seems to be clear.
As you might have noticed, there are quite some unclear points about access management here. Is there any common practice to provide access to AWS services (S3 and SQS in this case) for 3rd-party users of such SDK?
Options which I see at the moment:
We create IAM-user for users of the SDK which have access to some S3 resources and write permission for SQS.
We create additional server/layer between AWS and SDK which is writing messages to SQS instead of users as well as provides one-time short-living link for SDK to write data directly to S3.
First one seems to be OK, however I'm hesitant that I'm missing some obvious issues here. Second one seems to have a problem with scalability - if this layer will be down, whole system won't work.
P.S.
I tried my best to explain the situation, however I'm afraid that question might still lack some context. If you want more clarification - don't hesitate to write a comment.
I recommend you look closely at Temporary Security Credentials in order to limit customer access to only what they need, when they need it.
Keep in mind with any solution to this kind of problem, it depends on your scale, your customers, and what you are ok exposing to your customers.
With your first option, letting the customer directly use IAM or temporary credentials exposes knowledge to them that AWS is under the hood (since they can easily see requests leaving their system). It has the potential for them to make their own AWS requests using those credentials, beyond what your code can validate & control.
Your second option is better since it addresses this - by making your server the only point-of-contact for AWS, allowing you to perform input validation / etc before sending customer provided data to AWS. It also lets you replace the implementation easily without affecting customers. On availablily/scalability concerns, that's what EC2 (and similar services) are for.
Again, all of this depends on your scale and your customers. For a toy application where you have a very small set of customers, simpler may be better for the purposes of getting something working sooner (rather than building & paying for a whole lot of infrastructure for something that may not be used).