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Comment by jerf | Hacker News Reader

There's a lot of relevant differences between REST & GraphQL. It is possible to construct a REST endpoint that simply can't do any of those things, and such construction is a mid-level developer task at best. For instance, pagination of "all posts ever" is not uncommon, and clients won't be shocked to deal with it. GraphQL is enough harder to characterize the performance of that it definitely qualifies as a change in quantity that is itself a change in quality. Hypothetically, both approaches are vulnerable to all the same issues, but GraphQL is far more vulnerable.

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This is Wrong.

GraphQL only exposes what you ask it to. There are plenty of pagination plugins for GraphQL frameworks just as there are plugins to REST framework.

GraphQL can be restrictive as REST if you want it to be.

The point is GraphQL can be "as restrictive" as REST, but if you want to enable more efficient queries by knowing all the data that the frontend is requesting, you can. But the opposite isn't true of REST. With REST if you want more advanced functionality like that you have to define your own specification.

But then what's the point of using it if it's to get the limitation of REST?

You get something more complex, more expensive to maintain, consuming more resources, and configure it to basically be REST with extra steps.

> more complex, more expensive to maintain, consuming more resources,

Idk. Strawberry GQL and most GQL libraries are maybe equally as complex as the REST libraries for the same language. Strawberry and FastAPI I would say are equal in complexity and configuration.

It would be hard for me to say GQL is more expensive or consumes more resources. Opposite of the purpose and most uses of GQL.

In stawberry you make a method per field you want to retrieve, I would say it is indeed more complex and costly.

What? Its a method per collection you want to return. or else it is a type annotation. Exactly as complex as FastAPI or any other typed system.

Sorry, what? The original suggestion was that a developer would change things and it would cause performance problems. That same developer can change either a REST system or a GraphQL system and introduce the same performance issues in the same way, probably by adding a horrible N+1 query, or unbounded parallelism, or unbounded anything else.

Yeah, the client can't change the query if you don't let it specify a query, this is trivially true, but the developer can go break an API endpoint with the exact same result while trying to achieve the exact same business outcome.

The much more constrained input of the REST query means that the effect of changes on the API are much more comprehensible. Performance testing a particular REST endpoint is generally practical, and if a dev doesn't do it, the responsibility is reasonably placed on them. GraphQL means that you may do something you think is completely innocent like changing some index but for some query you didn't anticipate it trashes the performance. The range of things the dev of a GraphQL endpoint must be keeping track of is much larger than a REST endpoint, arguably exponentially so (though generally with a low power factor in practice, the possible queries are still exponentially complicated), and taking on any form of exponential responsibility is generally something that you should do only as a last resort, even if you do think your powers will stay low.

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