[newscom59]

> you can run any container (<10 GB), but it just has to implement the Lambda Runtime API[1]

So in other words, you can’t run any container.

Again, the entire point of containers is portability across execution environments. If I have to build special containers specifically for Lambda because they require these special runtimes, that defeats the entire point.

> You can't run a random container and expect Lambda to know how it should communicate with the world.

Google Cloud Run, which everyone keeps comparing this with, works exactly like that. Upload any random container, tell it which port to open, and bam... running application. You don’t have to mess around with adding any “Cloud Run runtimes” or modifying your code to add special “Cloud Run handlers”. Because that would be silly.

[mcintyre1994]

It's not really a very good comparison to be honest, because Lambdas integrate with a whole bunch of AWS services that send them events that aren't HTTP requests via a port.

I had exactly the same thought you're expressing here when I first built a Lambda to serve as a HTTP API manually after previously using Azure a tiny bit. In Azure you write their equivalent function and one of the built-in trigger options is HTTP, you enable that and immediately get a URL. Lambdas are quite close to that now I think if you're using the console UI, but you used to have to go through API gateway and set everything up manually.

But the point is that Lambdas aren't HTTP APIs that listen on a single port. They receive events that can be proxied HTTP requests via API Gateway, or messages on queues, or completely arbitrary invocations from step functions, or notifications that look nothing like HTTP from S3 buckets. I'd like the Cloud Run model when my lambda is acting like an HTTP API, but I don't think it'd be much fun to have to treat every AWS event as a full HTTP request for everything else.

I'm not very familiar with Google Cloud, but I think their equivalent is Cloud Functions which looks very similar to Lambda's pre-container model: https://cloud.google.com/functions/docs/writing

[NicBuihner]

I think your integration comment is spot on but might be an apples and oranges thing. On GCP everything is an HTTP request with an id_token in the header and event in the body, almost surprisingly so. As a result services like Cloud Functions and Cloud Run containers are quite literally just generic HTTP handlers. I suspect the integration feel of Lambda, which I agree with, might be a consequence of inter-service communication on AWS being relatively proprietary, or if that's not the right word, custom? Maybe the loose feeling of GCP is because everything is an HTTP request? It's almost like all of GCP runs on a built-in HTTP API Gateway setup by default. Honestly most of the time I feel like I'm living in HTTP-Request-land anyway, so not having to context switch when working with the platform is kind of nice sometimes.

[mcintyre1994]

Thanks for mentioning that, it definitely sounds like you can get a lot further with a HTTP handler in Google Cloud than you can in AWS. I can definitely see why avoiding that context switch is nice. I can also imagine it making things like metadata a lot easier if they use common and well documented headers, where in AWS every service will inevitably have its own way of putting stuff into the event. Everything in AWS feeling custom would be a pretty polite and fair way to put it IMO!

Do Google represent a JSON body HTTP event in a clean way? In AWS when a lambda is working as one, it receives the body as a string in the JSON representing the request, which you have to JSON decode. Again because not everything a Lambda can act on is JSON and your API doesn't have to be, what else can it really do I guess. But it does make it a bit horrible to generate that data to test with - we actually have a small script we use locally to convert a nicely formatted JSON file with test data into their HTTP-request-as-json format because it's so annoying to work with a large encoded JSON body. It's a small thing, but it means when you switch to working with a plain AWS event it's one less thing to think about. And I guess even if you're in HTTP-Request-Land and everything is nice JSON, it's still all going to be custom between services from there on by necessity.

[013a]

You can run any container. It just wouldn't run as you expect if you don't implement the lambda runtime api.

> Google Cloud Run, which everyone keeps comparing this with, works exactly like that.

Everyone does keep comparing this to GCR, wrongly. Not just because Lambda is not "bring any container" whereas GCR is, but more importantly because GCR and Lambda have very different operational models. GCR is a serverless platform for hosting web servers. Lambda is a serverless platform for event handling. The latter is a super-set of the former and thus requires more specific tools.

Yes, theoretically there could be a setup whereby you expose a port, and some lambda intermediary translates the invocation payload to an HTTP message your container can read. But I am endlessly fascinated why anyone would want that. I laugh a bit on how we've hit peak AWS where people here are legitimately asking for an HTTP request to hit an ALB, the ALB translates it into a lambda payload object, then a lambda component re-translates that payload back into an HTTP request, so your application can translate it into an object. Do you understand how insane that is?

The only tactile advantage lambda has over fargate is scale-to-zero. I think saving $7 per month is a pretty bad trade-off for the insane performance overhead and complexity a true docker-in-lambda solution would necessitate, and thus be unattractive to most consumers.