I'm not sure this is any more or less of a problem for REST APIs. What if your engineers change $client/$server and the new version makes really expensive queries? Well, ask them not to do that, then when some of them inevitably ignore you, start to review their code, terminate long-running queries, batch or pool fanouts so they don't take anything down, monitor new releases and roll back if anything breaks, etc.
If you're providing an external API like GitHub does, then that's a different story and I agree.
If you have separation between front and back end, then the back end team can elect to serve REST APIs which only permit selecting, filtering, grouping and pagination that they know they can support within defined latency bounds for a given traffic level.
Thing get more problematic when there's vertical ownership for a feature, where the UI needs just a few extra things and you end up with a REST response which is fatter and fatter, in the interest of avoiding round trips and client-side joins.
The problem with killing correct queries that take too long is that it shows up as intermittent failure that's dependent on server load and data cardinality. You might not find it in testing and it ships a bad experience to the customer before bugs are found. Whereas APIs which can't be so easily misused make it much harder to ship bugs.
> the back end team can select to serve REST APIs which only permit selecting, filtering, grouping and pagination that they know they can support within defined latency bounds for a given traffic level.
Why do you think that they can't do that with GraphQL? GraphQL isn't open ended. Its a highly restricted syntax for calling nested resources. If a resource is expensive simply don't nest it and make it a top level field and it is the same as REST?
Lots of nested resources are by default efficiently served by GraphQL because they are mostly returning single object foreign keys. Something that would take extra calls with REST.
GraphQL can have the same restrictions and performance guarantees as REST but the later is not necessarily true because in REST there is no standard way to define nested resource access.
I think the point here is, if you have to involve a backend team to add restrictions to the graphql endpoints and try to make good educated guesses where those might be, then the idea of frontend not needing backend engineers to query whatever they need becomes less of an advantage. So is the complexity of setting up graphql and then having your backend team try and make sure no frontend engineers can do terrible queries better for the software than custom rest APIs where needed and standard resource APIs everywhere else. Obviously it depends on the project. But I find the complexity of setting up and managing graphql often isn’t worth the pain, especially with schema first resource api designs and tooling like Google’s AIP linter.
> if you have to involve a backend team to add restrictions to the graphql endpoints and try to make good educated guesses where those might be, then the idea of frontend not needing backend engineers
No because if you dont do that you have to involve more engineers anyways to build the REST endpoints and keep modifying the rest endpoints.
GraphQL is also default restrictive (i.e. exposes nothing). You don't need to add engineers to make it restrictive.
In Startups typically:
-> Frontend changes most frequently
-> Backend "utility functions " changes less
-> Data model changes the least
Without Graphql your "backend" ends up needing to have a lot of work and changes because it is constantly needing to be updated to the needs of the most frequent changes happening on the frontend.
With GraphQL the only time you need to update the backend is when those "utility" functions change (i.e. 3rd party api calls, etc) or the data model changes.
So you end up needing substantially less backend engineers.
But you actually don't need to keep modifying the REST endpoints for most projects, that's what everybody is saying.
The vast majority of projects don't gain anything from this flexibility, because you don't have suddenly a 1000 of farmvilles copy cat that need their own little queries. You just have bob that need an order by.
> With GraphQL the only time you need to update the backend is when those "utility" functions change (i.e. 3rd party api calls, etc) or the data model changes.
This is akin to saying that "directly exposing the database is easier, you only have to change things if the data changes".
And yes this is true, but when the data changes, or the environment changes, the paradigm falls apart a bit, no? Which is what the backend code was for, insulation from that.
> In Startups typically:
Yes, so for a short lived, non-scaled application its far easier to do it one way, and maybe that's fine for most small apps (that will never scale far). I suspect a lot of the push back comes from larger, less nimble, more backwards-compat focused organizations/apps.
> This is akin to saying that "directly exposing the database is easier
Far from it actually. I am saying that in practice the data and queries that you perform on your Database actually tend to stabilize and you add less and less as time goes on.
By Allowing the frontend to select what combination of these pre-approved queries that you already approved it can use, you have to do less and less backend work when compared to REST where you have to do backend work for every query combination you want to serve.
> maybe that's fine for most small apps (that will never scale far).
I mean saying GQL doesn't scale for big apps is over looking one of the largest Corporate Software Orgs (FB) created and use it in production purposefully for managing large software APIs.
> By Allowing the frontend to select what combination of these pre-approved queries that you already approved it can use
Sure, so you are just filtering raw database access then. That doesn't make it any different - and, you still need to approve and filter these queries, so what exactly have you saved? I.e. either the front end engineers can change these filters, or not, so it amounts to the same thing in the case they can.
> I mean saying GQL doesn't scale for big apps is over looking one of the largest Corporate Software Orgs (FB) created and use it in production purposefully for managing large software APIs.
That's not a great argument, though, saying a large company with many resources is capable of supporting something does not make it a sustainable technical decision. They likely also have a very specific work structure they use to make it for them.
In fact thats a strong reason not to use it, if it requires enterprise level resources to use it effectively. There is a big difference between technologies that scale to enterprise and technologies that require enterprise...
It still comes down to, if you can achieve 99% of the same thing with autogenerated REST apis and a couple page specific apis, what, exactly, is worth the considerable increase in complexity for that remaining 1%? Making things regularly more complex is a hallmark of failed, bad technologies, and I suspect GraphQL will see the dustbin like SOAP did...
>You are bouncing back between it is ony for startups and it requires enterprise level maintenance. It can be used easily for both.
No, I never said that. You are the one that brought FB into the equation.
Just because it can be used for something does not mean that it should.
I said that that approach doesn't scale well, especially for frequent data/model changes. For small apps, where as you say, you have few data changes, by all means embed your database as closely as possible to you end user code.
Sqlite inside a c app or electron, e.g. No need for any API at all! Just raw query access.
Its nice GQL to generate stuff for small non-changing web apps, I'm sure. But once you get into more performance oriented, data-migration-style stuff, if there's not good support for changing the data and reacting to the environment, then adding complexity (GQL) to an already complex situation is a Bad Idea.
You never said what this 1% was, autogeneration is not a bonus when you already have to manually filter and route things. The simpler solution gets you there as well, with less fuss.
You think you don't have page specific apis, but if you are doing the manual filtering, then you still have them, you are just "hiding" them inside another language, that doesn't have a clear benefit? At least you can't say what it is, without going in circles, another sign GQL is probably ultimately a garbage technology...
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.
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.
> 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.
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.
Obviously depends on the API but a REST API that maps relatively cleanly to database queries is going to make it very clear on both the client and the server when it’s not scaling well.
If, at page load, I’m making 100 HTTP requests to fetch 100 assets then as a client side developer I’m going to know that’s bad practise and that we really ought to have some kind of multi-get endpoint. With GraphQL that gets muddy, from the client side I’m not really sure if what I’m writing is going to be a massive performance drag or not.
> What if your engineers change $client/$server and the new version makes really expensive queries?
Yes, so the cost benefit here is not in favor of GraphQL. If both technologies ultimately suffer from the same issues (what to do about unpredictable clients), but one is far more complex to implement and use (GraphQL), then there's a clear winner. Spoiler, its not GraphQL.
Page specific endpoints, I would argue, can do 99% of what GraphQL was trying to do. If you want to use it as some sort of template language for constructing page specific endpoints, that could be useful (the same way xml schema is useful for specifying complex xml documents).
But you can optimize a page specific endpoint, and do it with REST-style endpoint to boot.
Having a bunch of "simple" calls and optimizing for the "complex" ones that you need using metrics/analysis is what you should be doing, not creating a complex API that is far harder to break down into "simple" cases.
When you build a GraphQL server, you’re creating a system that outputs page-specific endpoints. They can be generated just-in-time (the default) or at build time (the general recommendation).
The engineering work involved shifts from building individual endpoints to building the endpoint factory. This shift may or may not be worth the trade off, but there are definite advantages, especially from the perspective of whomever is building the client. And once you factor in the ease at which you can introduce partial streaming with defer and streamable (granted they’re still WIP spec-wise), the experience can be pretty sublime.
This? Yeah, that seems neat, for command/batch queuing.
I'd be curious how it compares to e.g. rest apis returning refs to e.g. webrtc streams or tcp/udp ones for non-browser. I presume the main advantage would be client side.
Even a SQL query can suffer the same fate. Ever tried writing a SQL query against a distributed database that isn’t optimized for that read path?
I think that’s what’s really pointing out the root cause issues here, it’s not purely GraphQL’s problem, it’s the problems inherent to distributed systems.
If you're providing an external API like GitHub does, then that's a different story and I agree.