I guess it's better when the tooling you use has direct gql integration and builds the queries for you?
Because in my experience accessing the github APIs with "basic" HTTP libraries is way more annoying using v4 (graphql) than v3 ("rest") — it could also be that github's v4 API is dreadful mind, I wouldn't be surprised.
GQL should be more efficient because it's not returning 95% of garbage I don't need, but having to write 5-deep queries (because of the edge indirections) by hand is way more of a pain in the ass than performing two GET requests with a few parameters munged in the URLs. And then I still have to go and retrieve the information 5-deep in the resulting document.
Pagination is also awkward, because now you probably want multiple different queries (and thus multiple different resulting documents) so that your 2+ fetches don't retrieve unpaginated information you got the first time around. And it gets worse when nesting comes in.
I don't think graphql is generally a great experience when you consume it either.
For my own work, I took things in a different direction: I made a query language that parses as legal GraphQL using a vanilla parser, but has directives like `@filter, @recurse, @optional` etc. Instead of returning a giant fully-nested result, it flattens results and emits them row-by-row like a SQL database. This means the query evaluation can be lazy and incremental — if you write a query that has a billion results but only load 20 of them, then only 20 rows' worth of work happens.
My company has been using this in production for 6 years now across everything from TB-scale SQL clusters with X00,000 tables/views, to querying our own codebase, configuration, and deployment information to find and prevent bugs. I gave a 10min talk at a conference about this recently, if you'd like to learn more: https://www.hytradboi.com/2022/how-to-query-almost-everythin...
Project GitHub: https://github.com/obi1kenobi/trustfall
The pagination point is described well in nearby comments. It only applies when attempting to paginate across more than 1 dimension at once, like "get all pages of comments in an issue, and all pages of reactions for each comment".
Is paginating across multiple dimensions possible via the REST API?
It seems to me like the main friction that you and others are getting at is that GraphQL is more work to use than REST because you have to write a query. That's a fair point! Perhaps we could publish "canned" queries that are the equivalent of the most commonly used REST endpoints, or make them available for use in the API with a special param.
I worked a bit with GraphQL in the past, but never all that much. Now, I'm sure I could figure it out of I sit down, read the basics of GraphQL, familiarize myself with GitHub's GraphQL schema, etc. But ... it's all a lot of effort and complex vs. the REST API; even with a solid foundation in GraphQL there's still lots more parts.
GraphQL is kind of like giving people a schema to an SQL database and telling them that's an "API"; it kind of is, but also isn't really. There's a reason almost all applications have some sort of database layer (API!) to interact with the database, rather than just writing queries on the fly whenever needed.
There's a divide between at least two types of persona here. On one side is integrators building products and features on top of the GitHub API. For these people GraphQL is arguably superior since the learning curve is manageable and in exchange for scaling it you can make an extremely specific query that returns your product's exact data requirements. The cost of writing this query is amortized over the lifetime of your integration.
On the other side are e.g. users automating some part of their GitHub workflow to save themselves time. I can see how the REST API feels like a better choice here, it's certainly simpler to get started with.
For what it's worth, here[0] is an example of using the `gh` CLI's graphql feature to print a list of all repository URLs for a given organization by login, sorted in a relatively complicated way. It's more verbose than doing this with the REST API but significantly more flexible. This could just as easily be done with curl but as others have pointed out, pagination requires a minimal level of logic to implement, so it's more convenient to use an existing helper. This output gets flushed 10 lines at a time as pages come in, making it suitable to compose with other commands using pipes.
$ gh api graphql --paginate -f query='
query($endCursor: String) {
organization(login: "rails") {
repositories(first: 10, after: $endCursor,
orderBy: { field: STARGAZERS, direction: DESC }
) {
nodes {
url
stargazers {
totalCount
}
}
pageInfo { endCursor hasNextPage } # needed for auto-pagination
}
}
}' -q '.data.organization.repositories.nodes.[]'
# output follows
{"stargazers":{"totalCount":50643},"url":"https://github.com/rails/rails"}
{"stargazers":{"totalCount":5298},"url":"https://github.com/rails/webpacker"}
{"stargazers":{"totalCount":4849},"url":"https://github.com/rails/thor"}
{"stargazers":{"totalCount":4075},"url":"https://github.com/rails/jbuilder"}
# snip
{"stargazers":{"totalCount":3},"url":"https://github.com/rails/hide_action"}
{"stargazers":{"totalCount":2},"url":"https://github.com/rails/gem-buildkite-config"}
{"stargazers":{"totalCount":2},"url":"https://github.com/rails/sqlite2_adapter"}
{"stargazers":{"totalCount":1},"url":"https://github.com/rails/fcgi_handler"}
[0]: https://gist.github.com/brasic/14222db7b3f5873b84820477cca27... curl https://api.github.com/graphql -H "Authorization: bearer $TOKEN" --data @query.graphqlDead comment.
You don't need to write a different graphql query, use variables. Good graphql APIs will expose a start and limit field for Pagination.
You don't want to repeat these fetches in the followup queries, they're redundant, and assuming the API is rate-limited they will decrease your query budget for no value.
That counts double if you're fetching multiple paginated fields (which also adds to the awkwardness).
Your pagination is now two-dimensional, with each node's start/limit as points on its own axis.
Now add a third node to the query. Now you have three-dimensional pagination. This quickly goes off the rails.
Try writing a generic N-dimensional paginator for such a query to see why it's difficult. Even designing a sensible and reasonably flexible API for one is a headache.
TBF you could also deal with it using fragments I think, but still, not great.
Most of the simple ways of doing it with SQL are problematic. In these docs
https://docs.spring.io/spring-batch/docs/current/reference/h...
there is some discussion of the problems and some answers that go back to the mainframe era.
But very often, a result missing or duplicated in a few queries isn't a showstopper. On that case, pagination is very simple.
That is you are "full scanning" and making a report or doing something like a reconciliation process in a financial institution, it is not like some image boards where there is a link to the 1781th page of images but it spends forever loading it if you click on it.
I usually write my queries in GraphiQL (check some boxes) and then paste them into the app after I have them working right.
Or maybe TLDR "dear next generation of engineers: SQL is actually pretty good".
That was definitely true before Postgres got row security (admittedly in 2016, after GraphQL was released in 2015), but these days there's really no need to run an entire app server in front of your database just to implement permissions.
How is this a good thing for the backend or infra engineers? It's a mega facade without a lot of toolings to help the backend.
GraphQL reminded me of common ORM criticisms. Wide API surface area with a lot of rooms for accidents. And GraphQL made it worse by being exposed as a service.
With ORMs at least, the developer is likely either thinking about limitations, or really needs the guide-rails an ORM provides.
I doubt a lot of front end engineers, many of which probably have never optimized a DB, are thinking about the consequences of their queries.
To be clear, this is not just a problem for FE people. extremely normal for humans to become myopic in the areas they spend the most time in. FE does it, BE does it, management does it, everyone does it. Find a standard mobile engineer doing native iOS or Android, and they're going to be even more disconnected from the effects on the backend, and they come by it honestly. If you tend to specialize more in one area, building an awareness of your own biases/perspective, and exercising intentional empathy, can make a huge difference in how easy you are to work with.
When looking at dysfunctional engineering orgs, one of the first things I do is figure out where the "power" is and figure out their backgrounds. The most extreme example might be a company founded by a FE eng for whom backend is just a necessarily evil to support their app. Or a company founded by a BE guy for whom the real value is the API, and the clients are just there to abstract it for normal people.
Taking this in and finding a healthy balance of the way things are structured can help improve a dysfunctional org a lot. FE, BE, DevOps/Infra, etc are important pieces in an overall puzzle. Without a well-functioning team behind each, the company and product suffer.
It's trivial to use SQL to build objects from individual rows in a database. Which is all an ORM is really good for. Once you start doing reporting or aggregates, then ORMs fall apart. I've seen developers who, because they have a library built up around their flavor of ORM, go and do reporting with that ORM. What happens is this ORM report consumes all the RAM in the system and takes minutes to run. Or crashes.
ORM code hits performance issues because so many objects have to be built (RAM usage) and the SQL queries underneath the framework are not at all efficient. You can use OOP on top of SQL and get decent performance. But you need shallow objects built on top of complex SQL. ORM goes the opposite: large hierarchies of nested objects built from many dumb SQL queries.
This also ties into GraphQL. Think careful about the hierarchies you design. A flat API call that does one thing well is often better than some deeply-nested monster query that has to fetch the entire universe before it can reach that one field you need.
You should not ever need to implement your own GraphQL server. There are plenty to choose from.
1. query builder APIs, which can only generate valid queries, but you can control exactly what that query will be, 2. APIs that return basic data structures from the database, like maps or tuples.
Query languages like SQL are very powerful and easy to learn. And in my opinion, preferable to ORM approach of "what method calls do I need to make to trick the engine into executing the SQL I know would make this work?" ORMs add complexity and limitations that, in my opinion, are not worth the benefits.
but like any abstraction, if you don't know what's going on behind the curtain, they can turn into foot guns quick.
But that should be rare. If you're commonly bailing to raw sql, I'd say there's something wrong, probably a poor fit of the orm to the problem.
That said.
This is where the knowing what's going on behind the scenes matters.
If it had an algebra you could build a database engine that answers GraphQL queries like a conventional database engine or you could write a general purpose schema mapping and some tool would write the code that converts GraphQL queries to SQL queries or some other language.
As it is, GraphQL provides a grammar that looks like something people want to believe in but behind it all is a whole lot of nothing.
10min talk video: https://www.hytradboi.com/2022/how-to-query-almost-everythin...
Sure, you could set up an algebra that allows you to handle arbitrary queries for zero extra programmer effort, just like a SQL database engine does. And then you could even expose it to users, and let them execute arbitrary queries.
And then, later, after you're done cleaning the molten slag off the server room floor, you could stop and reflect on whether that was really such a necessary thing to do.
If it's not rigorously defined there are no limits, just what people can get away with.
With GraphQL you get the worst of both worlds that people can't write arbitrary queries but they can still trash the system. At least with undefined semantics people don't need to argue about whether or not they got the right answers.
Which, just for context - that's not me saying "graphQL is bad", it's me saying, "graphQL making it hard to do that is a feature, not a bug."
https://github.com/obi1kenobi/trustfall
(Hi Dustin!)
The whole concept is what happens when you let a smart person work on a small problem for far, far too long
This allows for lazy evaluation i.e. rows are produced only as they are consumed. So if you accidentally write a query that would produce a billion rows but only load 20, the execution of the query only happens for 20 rows + any batching or prefetch optimizations in the adapter used to bind the dataset to the query engine.
(1) There are usually some nodes of very high degree and traversing those nodes will explode your query, (2) if you are following N links and the average degree is d, you are going to come across dᴺ nodes and that is a lot of nodes as N gets big!
Tim-Berners Lee told me that if you can't send the whole graph you should send a subset of the graph that contains the most important facts.
It's a right answer but also a frustrating one to a programmer who sees correct implementation of algorithms to mean that you get the ticket done and they don't come at you with a ticket about it again. That is, that query I'm writing is part of an algorithm that depends on getting a certain answer and getting an uncertain answer for one query is like some spoiled milk that ruins the whole batch.
So why are we using it for so many naturally non-graph problems? 90%+ of developers' exposure to graphs is through tightly abstract interfaces, I could name maybe 3 graph-related algorithms off the top of my head, but could implement none of them without reading.
We could represent the text of this comment in a graph using one node for each unique character, but the result would be stupid, the operations would be slow, the representation needlessly complex, and implementations guaranteeably hard to work with
> Tim-Berners Lee told me that if you can't send the whole graph you should send a subset of the graph that contains the most important facts.
Indeed, I also caught the ReST buzz around the 2000-2003 timeframe, and turns out 20 years later nobody does that either, because in its purest form it's a pain in the ass for comparable reasons to the topic at hand
I've lost count of how many columnar SQL databases have been donated to the apache project and there are so many systems like Actian and Alteryx where data analysts hook together relational operators with boxes and lines.
I had a prototype of a stream processing engine that passed RDF graphs along the lines between the boxes that enable an "object-relational" model, you could eliminate the need for hard-to-maintain joins but I found that firms that had bought multiple columnar processing database companies believed in performance at all cost and couldn't care less for any system that couldn't be implemented with SIMD instructions.
It's a reasonable abstraction for structuring related bits of data (like would go in a typical relational database), and that abstraction can align with the developer's mental model easier.
E.g. ORMs basically convert SQL data into an in-memory graph. Likewise, graph database APIs are natively more object-y; you follow the edge from child to parent, instead of making a bit of data the same in both tables and then querying matching rows.
They're not perfect, and shouldn't be used everywhere (nor even many places they currently get used), but I can see the appeal of abusing them.
This rather sounds like a problem about the project manager and the project management methods that he uses.
Some coders really don't have discipline and projects never get done because they don't think things throw and keep sending half-baked patches that get sent back by test or the customer.
The role of management is to get those people working for their competitor and then have the "fixer" move in.
If you want to use GraphQL you should look for a database supporting it as an interface, or failing that look for an ORM system that supports GraphQL and whatever backend you want.
Trying to convert SQL to GraphQL or GraphQL to SQL is both equally difficult and has little to do with it not having an algebra (also I think most of it is just algebraic types, possibly lacking a proper sum type).
God forbid you should try to modify anything with GraphQL though, that part makes no sense whatsoever.
Unless you already know SQL, and you realise how small and simple the queries could be, then it's really not a great experience to be forced to use graphql.
I've been in web dev for 20 years but mostly in the front end space.
A couple of years ago I started doing full stack and trying different databases. For the past year or so I've been using Postgres and learning SQL. This is by far the best solution I've used so far. SQL is extremely expressive, powerful, and elegant.
The problem is that SQL has a strong learning curve which many devs want to avoid. I'm convinced this is the main reason stuff like Mongo or Prisma are so popular. I actually tried Prisma before raw SQL and I vastly prefer SQL for writing queries.
I deeply regret not having spent some time learning SQL years ago.
Standard SQL is a really simple grammar and a very small keyword set - there's basically selecting, updating, deleting, filtering with where, aggregate queries, grouping and joins, and that's like 95% of it. Sub-queries maybe too.
I think the problem is that it's declarative instead of imperative, which is really kind of a shock if you are not used to it (you can't go step by step, there's no debugger, there are no branches etc), and also that you have to think in sets in terms of your solution, which is also awkward when you're not used to it.
I think it's definitely worth it though, as nothing we have beats the relational model for CRUD, and there are so many great learning tools online, for example: https://sqlbolt.com/
Depends. It's easy if all you want to do is select * from whatever;
When you get into subqueries and a whole ton of joins to get the information you need, it can get pretty complicated.
I mean, we have a full university course which was 80% SQL, spanning 6 months.
TL;DR the language is not complicated. Actually using it, can be.
Some of these details go all the way down to the WiredTiger storage engine, but others are more vanilla (e.g. indexing strategies, atomicity guarantees, causal consistency, etc).
I personally abandoned SQL about a decade ago, but I can appreciate how clean the interface semantics are for even non-technical folks. There are certainly platform-specific implementation details that can matter, especially when you get into the world of partitioning. But largely for most service loads, you're writing queries that satisfy the known index constraints that you imposed on yourself rather than constraints resultant from implementation details.
(I totally realize that even with SQL, that last statement completely changes at a certain scale threshold.)
So you're in the camp that nosql data stores like dynamo/mongo is a good replacement for most SQL workflows? Can you expand on this a bit if you have the time?
I didn't jettison SQL because there was some fundamental limitation from a storage or scalability perspective. It was clear SQL wasn't going anywhere and would be a good infrastructure bet moving forward.
But initially what drew me to mongo was the clean interop between it and JS (Node.js is my runtime of choice). The shell is written in JS, you query (filter) using objects, you insert and update with objects. This seems like a small thing but this sort of developer experience over time is impactful. Everything feels very native to JS and it does so without any heavy abstractions like ORM/ODM.
After having used it now for 10+ years though, there's much more that I admire about it. Both from a pure architecture lens, but also from API perspective as well as it continues to get better.
To cherry pick an example— The new time series collection feature is a good example of that. For years, folks were using the bucket pattern [2] as a means to optimize query strategies for time series data by lowering timestamp cardinality. Now in v5.0, they give you a native way to specify the same kind of collection but they handle all the storage implementation details related to bucketing for you. Your API to interface with that collection remains mostly the same as any other collection. This sort of community-driven roadmap inertia is attractive to me as an engineer.
(Somewhat of a stream of consciousness here, but hopefully gives you some context as to why I made the switch so long ago)
[1] https://martinfowler.com/bliki/PolyglotPersistence.html [2] https://www.mongodb.com/blog/post/building-with-patterns-the...
When iterating on new systems, especially one with live users. I can keep users at different document schemas. If I'm careful I can make it so that all document schema changes don't break old ones yet also allow for new functionality not requiring mass migrations of documents.
CouchDB allows the db to just be exposed to the world directly. Projects where it's reasonable (user owned/controlled data particularly), I can stand up the system with 97% front end code 3% backend. Having the near entirety of your application stack in one place means you can use smaller more specialized teams and your overall areas of concerns are smaller without needing to draw up a formal spec for your data transport.
The whole GraphQL vs REST debate is meaningless when you don't even have to think about your transport stack between the server and the browser. There are other perks to this model such as providing a fully functional website/webapp even while offline. It's trivial to switch between a couchdb backend and local pouchdb copy of your db. Potentially lower bandwidth use while just transferring updated docs instead of consistent queries or asset fetching where the same data moves across the wire over multiple uses (not a win for single visits to a single page style sites). Keeping multiple clients on the same document set in sync without socket.io work.
Really? Of the dozens of languages that I've learned, SQL has been the easiest.
It really feels like it was designed for non-programmers.
If I have a User and who is trying to create a new Post, with Prisma you eventually set it up to do something like User.createPost(content).
What does createPost method look like with raw SQL? Does it read in from a .sql file that you pass values to?
However, a slightly unrelated comment on your choice of API design: this approach always introduces an asymmetry in the model that restricts what you can do. If you start allowing post imports that auto-detect authors, you now need a Post.create(content) and Post.setUser(user) too. And then your API users start wondering what's the idiomatic way to create a new post.
The problem is that you are making an early assumption that all posts will belong to a user, yet representing that in an SQL database with database relations, one being independent of the other (User: id, name, email...), and another referencing the first (Post: id, date, user -> User, content...). Your database model allows easy transition to allowing nulls for `user`, yet your API doesn't.
Moving to a more functional API makes this much more natural and less restrictive. Shallow DAOs for User and Post and a function create_post(content, user) may look just like a namespacing difference, but they match your database design more closely. If you want to allow nulls for user in the database, you just do the same in the create_post function.
You can wrap related functions into modules (or classes) — in the domain driven design, most of these would be port/adapter functions, but if your DAO classes are sufficiently shallow, they could be service or domain functions too, etc — they are still ultimately functions (no shared state or side effects).
The problem with using the ORM as you describe is that when you hit any sort of scale, you need to be doing bulk operations, otherwise your latency goes through the roof, to the point that the number of inefficient queries you are doing can tank the database. I speak from the experience of having seen a database collapse under the load of a backend written in this fashion having request load grow past a certain point — not pretty! The interim solution is to bulkify existing queries and functions in place to the greatest extent possible, while preparing for:
Converting a codebase from having endpoints doing individual ORM operations as described to having proper separation of concerns with a business logic layer between the endpoints and the database is a _massive_ cost. The earlier you implement that, the happier you will be in the longer term. It doesn’t have to be with raw SQL, but many bulk operations are much easier to express with SQL than with the ORM.
{ title: “Cool New Technology”, article: “I learned a thing today”, user_id: 1234 }
So createPost would just generate the appropriate query with the necessary parameters, and execute it.
The new generation of devs thinks that frameworks and ORMs will do the magic for them at no cost, but they don't. There is no substitute for leveraging your storage engine to the max.
The sad part is that databases have evolved and became much better in the last 20 years (I started with MySQL 3.x), but we just don't use them. Everyone acts like "microservices" solved all of our technical challenges. Right.
I work with "data" systems, where everything has been migrating in the other direction - to SQL - from custom code for last 5 years or more.
Yes, it's a bit like buying a set of silverware and insisting on using the handle as the business end incase you decide to switch your tool.
The point of GraphQL is mostly separation of backend/frontend and avoiding over-fetching/under-fetching. If those don't sound like a benefit, you should use REST.
Basically, with GraphQL you hide all the complexity behind generic-seeming API requiring one API call, whereas with REST you'd usually hit multiple endpoints for different data types.
GraphQL has the benefit of allowing the backend to smartly decide how to restrict the data (eg. do the joins between what would have been two bigger REST queries), but that incurs a development cost. The complexity is in marrying all the familiar optimization tricks for SQL databases with exposing that in a generic but still restricted way.
> On the other hand, when you are the one to implement the Graphql server, it feels like writing your own database. You have to create a query plan, handle optimizations, corner cases, etc.
If it’s so easy to craft any GraphQL query as an SQL query and let the RDBMS plan an execute the query, then shouldn’t it be easy to implement the GraphQL server on the backend?
Making it generic and performant at the same time is where the complexity is.
It would be akin to saying how, since knowing that you might need an index in the SQL database is simple, a RDBMS could decide to create those indexes for you.
This is true (as long as you expect both queries to be simple, or allow both to be complex).
But the conclusion you get up there is wrong and (obviously) does not follow from that. Creating a software that translate any one query into the other is a very difficult task.
The culprit is "micro" services. The whole thing was invented by a "software consulting" firm to milk as much billable hours as possible to make a system over-engineered and costy to support but easy to split into multi-layer/multi-stage outsourcing teams/phases, the industry fail into this stupid trap, and the burden was shifted into web & mobile clients, the next thing they realize is sometimes they have to make queries inside while loops.
If your data can be "planed" or "optimized" via a single centralized "GraphQL gateway", then it probably can be centralized inside a single database transaction call with so-out-of-date-you-should-never-use JOINs.
I recently had to render a user feed page, query uid for fids then fid with cmt-ids then each cmt-id for uids for avatar/nick and such, all from a stupid user profile lookup "micro" service, provided by another department, which only accept one param per query (spoiler alert: it's an "anti-pattern", but a sweet "optimization goals" for your next "sprint milestone"), I had to carefully and cleverly combine all those data needed make them as parallel lookups in async with a very good re-usable batch loader class. Which makes me wonder, if all those data sits right inside the same db, why bother scatter them into so many service pipes, then gather them in an PITA fashion?
As a developer I am not against GraphQL or Microservices because it pays, and it's a good pile of tech jargon to confuse the non-tech people and it really sticks, but from a pure technical point of view it's a waste of cpu0 power and emits needless CO2.
However, I think that's the key point to keep in mind when considering whether GraphQL is a good fit - if you don't already have multiple domain-specific services in your infrastructure, then adding a GraphQL gateway service doesn't make a huge amount of sense to me, because you could've just had your small team of front end developers talk to your small team of back end developers to create exactly the optimized endpoints they needed to solve the problem.
To me GraphQL really seems like a solution for an organizational problem, where there are dozens of teams who all maintain their own services and apps, and now a variety of front end teams want to combine different sets of data from services maintained by different sets of back end teams in a way that doesn't have alignment across the company as as far as deployment/release schedules go... Well now it makes sense to construct a flexible API schema maintained by and for front end specialists - it's just moving their already-existing data processing/join logic out of their various clients into a common server-side component.
I think the OP (and many of the comments in this discussion) is about making a graphql endpoint for public consumption.
if you are doing it solely for internal use, it does make sense that the "break even" point would be different.
What you are describing is called BFF I guess.
And apparently it's already out of date so let's again split BFFs into smaller parts.
https://martinfowler.com/articles/micro-frontends.html#Backe...
I am not against services, it's organizational motivated "micro" services I am very afraid of.
I don't know the whole origin story. It definitely does feel like something Martin Fowler would come up with. But I blame Google for really making it a trend:
https://www.youtube.com/watch?v=3Ea3pkTCYx4
And you can see they understand the whole problem with microservices. It's the same thing The Mythical Man-Month was trying to tell everyone decades ago[1]
> When n people have to communicate among themselves, as n increases, their output decreases
Microservices exasperates this. It is the Multics model. Each microservice implements its own, often wildly different, API. Which every bit of code that needs to use that microservice has to go and implement.
I do agree that without a good API design it can become a mess quickly and most companies go for microservices without a clear understanding of what goals they are trying to achieve with microservices. For those companies, sticking with a monolith would've probably worked better.
I've even heard cases where companies went back to a monolith and I think that is actually a smart decision in some cases.
But I definitely don't think it is a waste of CPUs power.
Certainly there have been problems with queries that had unacceptable performance, even those that took down the whole API server and database. Of course that wasn't a novelty with our REST APIs either. It certainly is an issue with GraphQL, but it has been a managable one for us.
Largely this is because the API is not public, and it doesn't have to simply handle anything that is thrown at it. When we see a frequent, slow GraphQL query in a report, we have many options to deal with it, including going to the front-end team and asking them to query in another way, and I have had to resort to that. Often I can optimize the code instead.
But that hasn't been a huge problem, especially compared to the great benefits of pushing most of the data work to the front-end. And the size and complexity limitations we've built into the API handle such problems seemlessly most of the time. The caller gets a clear error message that specifies the problem, and they can usually compensate very quickly with an altered query.
When they can't then I get involved and sometimes have to say, uh, we can't do that ... without scads of extra work. And the work on my plate today is for one of those scads.
I was doing lots of REST API work before GraphQL APIs, and my own and our corporate experience is that GraphQL solves a lot more problems than it causes.
Instead of doing a simple GET /a/b/1/c and presenting that data structure, they now need to define a query, think about what resources to pull into that query etc. If the query ends up being slow, they have to understand why and work on more complex changes than simply asking the BE team for a smaller response with a few query params.
I hit this problem when contemplating exposing the API of the application I work on to customers, to be used in their automation scripts.
We quickly realized that expecting them to learn our data model and how to use it efficiently would be much more complicated than exposing every plausible use-case explicitly. We could do this on the "API front-end" by building a set of high-level utilities that would embed the GraphQL queries, but that would essentially double much of the work being done in the front-end (and more than double if some customers want to use Python scripting while others want JS and others want TCL or Perl).
So, we decided that the best place to expose those high-level abstractions is exactly the REST API, where it is maximally re-usable.
I’ve seen this a lot from backend teams, and it’s beyond frustrating.
Because now my nice clean frontend code suddenly has to deal with a bunch of franken query logic simply because the backend team cannot be bothered to alter their “pristine” API.
Never mind that this means a thousand requests where one graphql query would have sufficed.
I've never seen it as nuts and a bare pre-req ofodern computing. Apparently this view is the subject of widespread controversy amongst peers.
I think this is the key point.
Maybe the trick is to keep it simple? There's no need for a bi-directional graph or advanced filtering. But if there really is, it's not like sticking to REST would make that any easier. Some things are just hard, no matter the interface.
Graphql gives a better way to request nested schemas and handle relationships and recursion. But when you cross that line, the client now would get ideas and starts asking "Why not be able to do that operation on the 5 level deep object?". Now you have to either not allow the client to do that, or you have to "rewrite the database" to make recursion optimal.
This is not a problem of Graphql. This is an HTTP problem. When you need to promote the database querying layer over HTTP, then you have a problem regardless.
The problem might be to get those 352nd pages of every book with the title starting with "A" sitting on 3rd shelf of every city library: when there are unbounded results nested deeper than top-level, and possibly those multiple times, that's when it gets hairy.
This isn't new, there's plenty of sloppy REST APIs, but it was so much easier and less painful to explore and stitch together pieces of an imperfect REST API than it is to interact with a bad GraphQL API.
So when a query requests a list of users, and then every users friends, that becomes two queries: one to load all the users, and one to load all the friends for all those users. The net effect is that your number of queries is O(query depth) rather than O(objects requested).
Admittedly this does tend to work best with more K-V oriented data that truly relational data, and might be hard to retrofit onto a brownfield project, but i’ve never found it all that hard to do.
In my opinion graphql and rest can both be super cute in simple everyday queries. But I am thinking that people are creating databases like postgres, mongodb, neo4j, etc, are doing exactly that. Trying to give us the power to query our data efficiently. Why not be able to expose directly the database and just add a layer for security, control, decorating and other stuff that would add value. Why rewrite databases?
But APIs can have different use cases. It’s usually considered bad to directly expose your table schema over GraphQL because it locks you in and makes it hard to change your data model over time. And not all API access is “get this data” and “set this data” — it can be difficult to express complex logic in just a database. And of course, some GraphQL APIs aren’t backed by a database - they’re backed by other services (a la the “backend for frontend” pattern).
I’m very pro choosing the simplest solution that works — but sometimes, the simplest solution does bring some complexity in exchange for other trade offs (like flexibility).
When I saw GraphQL come out, I knew that what you are saying would happen.
In the data federation tool I worked in, SQL was the interface abstraction to join across heterogenous platforms (think of things like Presto/Trino or Dremio). GraphQL as an interface requires the same underlying infrastructure as that data federation tool I worked on in terms of query analysis, parsing, planning, optimization, execution, etc.
Those are "hard problems" due to lack of standardized interfaces, access patterns, direct data access, I/O, network bandwidth and infra related latency, costs, compatibility, data types, etc. These problems are distributed system problems coupled with often incompatible interface layers (e.g., even if you are using multiple SQL databases with GraphQL, you run into the same).
If your scale is such that you can build GraphQL on a handful of systems and for a handful of use cases, great! If you have to go to a certain larger scale, you're back into federation territory (which in the app layer might also be called API composition).
One potential option - when you reach the point where you need complex GraphQL query coordination, more than seems to make sense to implement, pair it with a data federation tool such as Presto/Trino, Dremio, Denodo, or research approaches such as caching/materialized views (engines like that are becoming decoupled from databases, such as Materialize.io) - and let those engines do the hard work.
In that case your work becomes more like GraphQL -> SQL or API -> a data federation, caching or materialization platform. CQRS and event sourcing plays a role here too.
Consider also, the possibility that if you are willing to accept a bit of delay in aggregated results from multiple systems, doing those compositions or aggregations in the data platform layer, and simple feeding those to the GraphQL interface. That could even be done in a single database/data platform if you really wanted without too much fancy federation tech.
Federation is powerful but complex. It seems like a fun hard problem, but for many tech teams, it can be a complexity and time suck. My recommendation would be try to avoid building that if you can.
How about caching? It feels like GraphQL tries to win some (arguable) flexibility in putting together clients and in the process throws out most of the operational advantages of resource-based APIs with significant disadvantages in both how to put together a backend.
Is it elegant? No.
Do you have another service to manage? Yes
Will you pay someone else to do it for you? Possibly
I think there are already products trying to do that. But how many layers of abstractions and dependencies are you willing to have in your everyday processes?
It does a lot of client-side caching for you. The documentation is atrocious though IMO. I'm not sure if there exists a similar framework for backend caching.
Relay is a GraphQL client. That's the irrelevant side of caching, because that can be trivially implemented by an intern, specially given GraphQL's official copout of caching based on primary keys [1], and doesn't have any meaningful impact on the client's resources.
The relevant side of caching is server-side caching: the bits of your system that allow it to fulfill results while skipping the expensive bits, like having to hit the database. This is what really matters both in terms of operational costs and performance, and this is what GraphQL fails to deliver.
Take a look at this. Either you didn't know what's challenging about caching nested graph data, or we have different definitions of triviality/interns.
I repeat: client-side caching is not a problem, even with GraphQL.
The technical problems regarding GraphQL's blockers to caching lies in server-side caching.
For server-side caching, the only answer that GraphQL offers is to use primary keys, hand-wave a lot, and hope that your GraphQL implementation did some sort of optimization to handle that corner case by caching results.
Don't take my word for it. It's really that bad.
Does it, though? It seems it really doesn't, nor was GraphQL designed with HTTP caching in mind.
The only references to caching in GraphQL are vague hand-waiving arguments about how theoretically GraphQL implementations might be implemented with some sort of support for caching primary keys.
But any type of HTTP caching is automatically excluded from GrahQL.
To put it differently, is there any third-party caching solution for GraphQL? As far as I could gather, the answer is no.
Oh so one of the most basic feature of any API, one which has a direct impact on scalability and motivates entire product lines and businesses like CDNs, is now "unnecessary"?
> you can just cache GraphQL like REST,
Go ahead and show one example, please.
I'm not sure you understand the problem at all.
Are you actually able to show an example or not? Because changing the HTTP verb doesn't magically change the problem, and passing query parameters as a request document renders these queries uncacheable.
> You can use Apache, nginx, squid, any proxying webserver worth its salt...
Great, pick the one you're familiar with, and just show the code. Well, unless you're not "worth its salt" or are completely oblivious to the problem domain.
Note that I made a very primitive implementation. Depending on which GraphQL node is queried, the request will be cached by the proxy or not. Apollo GraphQL server has much more fine grained methods of allowing caching (see https://www.apollographql.com/docs/apollo-server/performance...) however I left the example code crude so you see exactly what's going on under the hood.
Sorry, that doesn't cut it at all. Far from it. Being able to cache a response is not the same thing as optimizing queries that hit your database. Being able to cache a response means not having to hit your database to begin with, and save up on things like traffic going into your database, and round trip time.
With REST APIs I can get a web service to return responses that are HTTP cacheable, put a nginx instance between the ingress controller and the web service, and serve responses to REST clients without even touching the web service that provides the REST API. I can even deploy nginx instances in separate regions.
What's GraphQL's response to this basic usecase?
You can then use these claims values in your authorization (permissions) layer.
IE, when a user logs in, you can sign a claim with "X-Hasura-User-ID" = 1, and "X-Hasura-Org-ID" = 5, and then put rules on tables like:
> "Role USER can SELECT rows in table 'user' WHEN X-Hasura-User-ID = user.id"
> "Role USER can SELECT rows in table 'organization' WHEN X-Hasura-Org-Id = organization.id"
There's more depth to it than this, but this is the gist of it.That's not permissions in the general sense of authorisation, that should just be modelled as any other "business logic". Put that article_limit in the users table and join it in the selects.
Edit: or tracking the users article views with timestamps, and making a select aggregate over the month..
> "customer Y cannot insert any more orders if total outstanding/unpaid amount of invoices in last 30 days succeeds Z"
insert into orders select from user a inner join invoices b etc.. any kind of limitless complexity here on how you want to limit the orders.
But you can still implement this easily in queries, so for example granting the client only read permissions, plus execution permissions on certain database functions, and inside these functions you can implement the constraints.
What I'm trying to say, is that you don't necessarily need any backend "services" java etc, to implement these type of constraints, they can be modelled as any other business logic in the database.
As for flexibility, do you mean authentication or authorization?
SSO can be done at the SQL server level (MSSQL has it and so does Postgres, don't know about others), but handling the SSO part in your app and using "set role" and passing a user ID for your row level security policies to use is easier to set up and more flexible.
Clean separation between user and machine accounts can absolutely be done with MSSQL and Postgres.
Triggers, functions or whatever you use are just code; yes, that is my pitch: Have your buisness logic in code, ideally in a dedicated BE API endpoint instead in the DB.
That's your business logic in the database right there.
So no, you don't get to wiggle out of that one.
Unit testing PL/pgSQL is nasty.
But unit testing is not nasty at all: just look up pgTAP.
What's nasty is that the incumbent development model intersperses data modelling constraints in the database and in the non-db code, and then we test one layer implicitly from another layer.
You'd usually have backend code guarding against constraint-violating entries, and then you'd have a database constraint too.
So what you need to do now is test almost exactly the same thing from your code test and from your database test to get proper coverage.
Enter declarative ORM schemas, and suddenly there's not even a guarantee that the schema you are running really matches what your ORM thinks the schema is.
For that reason, I prefer all those SQL-based database migration/evolution approaches over ORM-based schema generation, coupled with pure SQL tests (eg. with pgTAP, but yeah, any tool can do).
Basically, even for declarative code, there should be a unit test, a la double-entry bookkeeping in accounting.
And even if this is what I prefer and believe is only right, I never worked on a large company project that did all of these things.
So I don't think the entire topic should be easily dismissed: while unit testing is simple, have you ever worked on a project that tested db-schema embedded logic exactly at the right level (and not the level up)?
The nicest thing about Prisma is that it is a declarative single-source-of-truth for our data models. Everything resides in one schema, all changes to database models and all migrations run through Prisma, and, best of all, strong types are inherently built in.
The team is also building useful middleware like field-level encryption; all of this together makes Prisma a very complete package.
Of course, there is a price for this convenience — we sacrifice some higher-level DB-side features. But Prisma is such a competent tool that we don't miss them much.
Querying everything through one API (which relays requests to other microservices, if necessary) and having one Postgres DB which acts as the "endpoint" for all of our data is a very clean model.
For edge cases, it's also possible to write custom resolvers. Prisma doesn't prohibit that.
Is this still true if the structure of the data is relatively simple, but you have tens of millions of users? Say the data that is returned (per user) has 20 or 30 properties in total (for each user), and you are only ever asking for specific data about an individual user.
In the end you might think to yourself “why am I doing this, when my SQL database already has query optimisation?”. And it’s a fair question, you are onto it. Try one of those auto-GraphQL things instead. EdgeDB (https://edgedb.com) does it as we speak, runs atop Postgres. Save yourself the enormous effort if you’re only building a GraphQL API for a single RDBMS, and not as a façade for a cluster of microservices and databases and external requests.
Or just nod to your boss and go back to what being a backend developer has always meant: laboriously building by hand completely ad hoc JSON versions of SQL RDBMS schemas, each terribly unhappy in its own way. In no way does doing it manually but presenting GraphQL deviate from this Sisyphean tradition.
I read in the article that NOT having GraphQL exactly match your DB schema is a best practice. My response is “did a backend developer write this?” Sounds awfully convenient for job security!
Out of curiosity, would functionality like this implemented in graphql solve your issues?
we had a challenge like what you describe though, and were able to avoid new queries by representing the relationships as objects. in so doing, we leverage row level security and jwt claims, which is an approach to authorization which has high epistemical legibility.
On the other hand, when you are the one to implement the Graphql server, it feels like writing your own database. You have to create a query plan, handle optimizations, corner cases, etc.
Also if you really want to provide a graph experience, with inverse connections, filter on relationships and other advanced stuff... get ready to burn your mind and your soul.