Why I stopped using JSON for my APIs

https://aloisdeniel.com/blog/better-than-json

by barremian • 8 months ago

180 238 8 months ago

spagoop2• 8 months ago

Is it just me or is this article insanely confusing? With all due respect to the author, please be mindful of copy editing LLM-assisted writing.

There is a really interesting discussion underneath of this as to the limitations of JSON along with potential alternatives, but I can't help but distrust this writing due to how much it sounds like an LLM.

port113• 8 months ago

I don't think it's LLM-generated or even assisted. It's kinda like how I write when I don't want to really argue a point but rather get to the good bits.

Seems like the author just wanted to talk about Protobuf without bothering too much about the issues with JSON (though some are mentioned).

dkdcio• 8 months ago

do you have any evidence that the author used a LLM? focusing on the content, instead of the tooling used to write the content, leads to a lot more productive discussions

I promise you cannot tell LLM-generated content from non-LLM generated content. what you think you’re detecting is poor quality, which is orthogonal to the tooling used

spagoop2• 8 months ago

Fair point, to be constructive here, LLMs seem to love lists and emphasizing random words / phrases with bold. Those two are everywhere. Not a smoking gun but enough to tune out.

I am not dismissing this as being slop and actually have no beef with using LLMs to write but yes, as you call out, I think it's just poorly written or perhaps I'm not the specific audience for this.

Sorry if this is bad energy, I appreciate the write up regardless.

pavel_lishin• 8 months ago

Is it just me or is this article insanely confusing?

I didn't find it confusing.

I found it unconvincing, but the argument itself was pretty clear. I just disagreed with it.

phyzome• 8 months ago

It wasn't confusing, but yeah, it smelled strongly of LLMs.

codewritero• 8 months ago

I love to see people advocating for better protocols and standards but seeing the title I expected the author to present something which would be better in the sense of supporting the same or more use cases with better efficiency and/or ergonomics and I don't think that protobuf does that.

Protobuf has advantages, but is missing support for a tons of use cases where JSON thrives due to the strict schema requirement.

A much stronger argument could be made for CBOR as a replacement for JSON for most use cases. CBOR has the same schema flexibility as JSON but has a more concise encoding.

port113• 8 months ago

I think the strict schema of Protobuf might be one of the major improvements, as most APIs don't publish a JSON schema? I've always had to use ajv or superstruct to make sure payloads match a schema, Protobuf doesn't need that (supposedly).

thayne2• 8 months ago

One limitation of protobuf 3 schemas, is they doen't allow required fields. That makes it easier to remove the field in a later version in a backwards compatible way, but sometimes fields really are required, and the message doesn't make any sense without them. Ideally, IMO, if the message is missing those fields, it would fail to parse successfully. But with protobuf, you instead get a default value, which could potentially cause subtle bugs.

youngtaff• 8 months ago

We need browsers to support CBOR APIs… and it shouldn’t be that hard as they all have internal implementations now

deathanatos• 8 months ago

I suppose I should publish this, but a WASM module, in Rust, which just binds [ciborium] into JS only took me ~100 LoC. (And by this I mean that it effectively provides a "cbor_load" function to JS, which returns JS objects; I mention this just b/c I think some people have the impression that WASM can't interact with JS except by serializing stuff to/from bytestrings and/or JSON, which isn't really the whole story now with refs.)

But yes, a native implementation would save me the trouble!

[ciborium]: a Rust CBOR library; https://docs.rs/ciborium/latest/ciborium/

written-beyond2• 8 months ago

Idk I built a production system and ensured all data transfers, client to server and server to client were proto buf and it was a pain.

Technically, it sounds really good but the actual act of managing it is hell. That or I need a lot of practice to use them, at that point shouldn't I just use JSON and get on with my life.

Arainach2• 8 months ago

What issues did you have? In my experience, most things that could be called painful with protobuf would be bigger pains with things like JSON.

Making changes to messages in a backwards-compatible way can be annoying, but JSON allowing you to shoot yourself in the foot will take more time and effort to fix when it's corrupting data in prod than protobuf giving you a compile error would.

written-beyond2• 8 months ago

Well at the bare minimum setting up proto files and knowing where they live across many projects.

If they live in their own project, making a single project be buildable with a git clone gets progressively more complex.

You now need sub modules to pull in your protobuf definitions.

You now also need the protobuf tool chain to be available in your environment you just cloned to. If that environment has the wrong version the build fails, it starts to get frustrating pretty fast.

Compare that to json, yes I don't get versioning and a bunch of other fancy features but... I get to finish my work, build and test pretty quickly.

barremian3• 8 months ago

I think the it-just-works nature and human readability for debugging JSON cannot be overstated. Most people and projects are content to just use JSON even if protos offer some advantages, if not only to save time and resources.

Whether the team saves times in the longer when using protos is a question in its own.

IshKebab2• 8 months ago

There are plenty of it-doesn't-just-work things about JSON though. Sending binary data or 64-bit integers is a huge pain. Or maps with non-string keys, or ordered maps. Plus JSON doesn't scale well with message size because it doesn't use TLV so parsing any of a message requires parsing all of it.

It's not some perfect format.

That said, I'm disappointed with Protobuf too. Especially the handling of optional/default fields. I believe they did eventually add an `optional` tag so you can at least distinguish missing vs default field values.

The lack of required fields makes it very annoying to work with though. And no, there's no issue with required fields in general. The only reason it doesn't have them is because the implementation in Protobuf 2 caused issues and Google had to have a smooth transition from that.

If you're starting a greenfield project it seems silly to opt in to Google's tech debt.

If you're thinking "but schema evolution!!" well yeah all you need is a way to have versioned structs and then you can mark fields as being required for ranges of versions. So you can still remove required fields without breaking backwards compatibility.

esafak2• 8 months ago

It's premature and maybe presumptuous of him to be advertising protobufs when he hasn't heard of the alternatives yet. I'll engage the article after he discovers them...

pzmarzly• 8 months ago

With Protobuf, that’s impossible.

Unless your servers and clients push at different time, thus are compiled with different versions of your specs, then many safety bets are off.

There are ways to be mostly safe (never reuse IDs, use unknown-field-friendly copying methods, etc.), but distributed systems are distributed systems, and protobuf isn't a silver bullet that can solve all problems on author's list.

On the upside, it seems like protobuf3 fixed a lot of stuff I used to hate about protobuf2. Issues like:

if the field is not a message, it has two states:
- ...
- the field is set to the default (zero) value. It will not be serialized to the wire. In fact, you cannot determine whether the default (zero) value was set or parsed from the wire or not provided at all

are now gone if you stick to using protobuf3 + `message` keyword. That's really cool.

brabel2• 8 months ago

No type system survives going through a network.

dhussoe4• 8 months ago

yes, but any sane JSON parsing library (Rust Serde, kotlinx-serialization, Swift, etc.) will raise an error when you have the wrong type or are missing a required field. and any JSON parsing callsite is very likely also an IO callsite so you need to handle errors there anyways, all IO can fail. then you log it or recover or whatever you do when IO fails in some other way in that situation.

this seems like a problem only if you use JSON.parse or json.loads etc. and then just cross your fingers and hope that the types are correct, basically doing the silent equivalent of casting an "any" type to some structure that you assume is correct, rather than strictly parsing (parse, don't validate) into a typed structure before handing that off to other code.

connicpu• 8 months ago

Regardless of whether you use JSON or Protobuf, the only way to be safe from version tears in your serialization format is to enforce backwards compatibility in your CI pipeline by testing the new version of your service creates responses that are usable by older versions of your clients, and vice versa.

sevensor2• 8 months ago

Yeah, no discussion of this topic is complete without bringing up schema evolution. There’s a school of thought that holds this is basically impossible and the right thing to do is never ever make a breaking change. Instead, allow new fields to be absent and accept unrecognized fields always. I think this is unsustainable and hard to reason about.

I have not found it difficult to support backwards compatibility with explicit versioning, and the only justification I’ve seen for not doing it is that it’s impossible to coordinate between development teams. Which I think is an indictment of how the company is run more than anything else.

volemo• 8 months ago

S-expressions exist since 1960, what more do you need? /s

Jemaclus• 8 months ago

"Better than JSON" is a pretty bold claim, and even though the article makes some great cases, the author is making some trade-offs that I wouldn't make, based on my 20+ year career and experience. The author makes a statement at the beginning: "I find it surprising that JSON is so omnipresent when there are far more efficient alternatives."

We might disagree on what "efficient" means. OP is focusing on computer efficiency, where as you'll see, I tend to optimize for human efficiency (and, let's be clear, JSON is efficient _enough_ for 99% of computer cases).

I think the "human readable" part is often an overlooked pro by hardcore protobuf fans. One of my fundamental philosophies of engineering historically has been "clarity over cleverness." Perhaps the corollary to this is "...and simplicity over complexity." And I think protobuf, generally speaking, falls in the cleverness part, and certainly into the complexity part (with regards to dependencies).

JSON, on the other hand, is ubiquitous, human readable (clear), and simple (little-to-no dependencies).

I've found in my career that there's tremendous value in not needing to execute code to see what a payload contains. I've seen a lot of engineers (including myself, once upon a time!) take shortcuts like using bitwise values and protobufs and things like that to make things faster or to be clever or whatever. And then I've seen those same engineers, or perhaps their successors, find great difficulty in navigating years-old protobufs, when a JSON payload is immediately clear and understandable to any human, technical or not, upon a glance.

I write MUDs for fun, and one of the things that older MUD codebases do is that they use bit flags to compress a lot of information into a tiny integer. To know what conditions a player has (hunger, thirst, cursed, etc), you do some bit manipulation and you wind up with something like 31 that represents the player being thirsty (1), hungry (2), cursed (4), with haste (8), and with shield (16). Which is great, if you're optimizing for integer compression, but it's really bad when you want a human to look at it. You have to do a bunch of math to sort of de-compress that integer into something meaningful for humans.

Similarly with protobuf, I find that it usually optimizes for the wrong thing. To be clear, one of my other fundamental philosophies about engineering is that performance is king and that you should try to make things fast, but there are certainly diminishing returns, especially in codebases where humans interact frequently with the data. Protobufs make things fast at a cost, and that cost is typically clarity and human readability. Versioning also creates more friction. I've seen teams spend an inordinate amount of effort trying to ensure that both the producer and consumer are using the same versions.

This is not to say that protobufs are useless. It's great for enforcing API contracts at the code level, and it provides those speed improvements OP mentions. There are certain high-throughput use-cases where this complexity and relative opaqueness is not only an acceptable trade off, but the right one to make. But I've found that it's not particularly common, and people reaching for protobufs are often optimizing for the wrong things. Again, clarity over cleverness and simplicity over complexity.

I know one of the arguments is "it's better for situations where you control both sides," but if you're in any kind of team with more than a couple of engineers, this stops being true. Even if your internal API is controlled by "us," that "us" can sometimes span 100+ engineers, and you might as well consider it a public API.

I'm not a protobuf hater, I just think that the vast majority of engineers would go through their careers without ever touching protobufs, never miss it, never need it, and never find themselves where eking out that extra performance is truly worth the hassle.

Arainach2• 8 months ago

If you want human readable, there are text representations of protobuf for use at rest (checked in config files, etc.) while still being more efficient over the wire.

In terms of human effort, a strongly typed schema rather than one where you have to sanity check everything saves far more time in the long run.

Aldipower• 8 months ago

Great writing, thanks. There are of course 2 sides as always. I think especially for larger teams and large projects Protobuf in conjunction with gRPC can play wisely with the backwards compatibility feature, which makes it very hard to break things.

PantaloonFlames3• 8 months ago

Yes to all of this.

Also the “us” is ever-changing in a large enough system. There are always people joining and leaving the team. Always, many people are approximately new, and JSON lets them discover more easily.

catchmeifyoucan• 8 months ago

I wonder if we can write an API w/ JSON the usual way and change the final packaging to send it over protobuf.

pstuart• 8 months ago

If you're using Go then this framework let's you work with protobufs and gives you a JSON rest-like service for free: https://github.com/grpc-ecosystem/grpc-gateway

bglusman2• 8 months ago

Sure... https://protobuf.dev/programming-guides/json/

I was pushing at one point for us to have some code in our protobuf parsers that would essentially allow reading messages in either JSON or binary format, though to be fair there's some overhead that way by doing some kind of try/catch, but, for some use cases I think it's worth it...

lanigone• 8 months ago

envoy (the proxy) can transcode RESTful APIs to internal grpc services and vice versa. you can even map like url params etc. to proto fields. it works well, even server streaming.

brabel2• 8 months ago

Mandatory comment about ASN.1, a protocol from 1984, already did what Protobuf does, with more flexibility. Yes, it's a bit ugly but if you stick to the DER encoding it's really not worse than Protbuf at all. Check out the Wikipedia example:

https://en.wikipedia.org/wiki/ASN.1#Example_encoded_in_DER

Protobuf is ok but if you actually look at how the serializers work, it's just too complex for what it achieves.

bloppe4• 8 months ago

What makes it too complex in your opinion?

kragen5• 8 months ago

Experience with ASN.1.

zzo38computer11• 8 months ago

I also think ASN.1 DER is better (there are other formats, but in my opinion, DER is the only good one, because BER is too messy). I use it in some of my stuff, and when I can, my new designs also use ASN.1 DER rather than using JSON and Protobuf etc. (Some types are missing from standard ASN.1 but I made up a variant called "ASN.1X" which adds some additional types such as key/value list and some others. With the key/value list type added, it is now a superset of the data model of JSON, so you can convert JSON to ASN.1X DER.)

(I wrote a implementation of DER encoding/decoding in C, which is public domain and FOSS.)

pphysch2• 8 months ago

ASN.1, a protocol from 1984, already did what Protobuf does, with more flexibility.

After working heavily with SNMP across a wide variety of OEMs, this flexibility becomes a downside. Or SNMP/MIBs were specified at the wrong abstraction level, where the ASN.1 flexibility gives mfgs too much power to do insane and unconventional things.

morshu900116• 8 months ago

Yeah same, ASN.1 was a nightmare when I was dealing with LTE

cryptonector23• 8 months ago

That's not ASN.1's fault though.

dgan• 8 months ago

I honestly looked up for a encoder/decoder for python/c++ application, and couldnt find anything usable; i guess i would need to contact the purchase department for a license (?), while with protobuf i can make the decision myself & all alone

morshu900116• 8 months ago

ASN.1 is way overengineered to the point of making it hard to support. You don't need inheritance for example.

zzo38computer11• 8 months ago

it is not necessary to use or to implement all of the data types and other features of ASN.1; you can implement only the features that you are using. Since DER uses the same framing for all data types, it is possible to skip past any fields that you do not care about (although in some cases you will still need to check its type, to determine whether or not an optional field is present; fortunately the type can be checked easily, even if it is not a type you implement).

strongpigeon• 8 months ago

Protobuf is ok but if you actually look at how the serializers work, it's just too complex for what it achieves.

Yeah. I do remember a lot of workloads at Google where most of the CPU time was spent serializing/deserializing protos.

ses1984• 8 months ago

I feel like most high throughput distributed systems eventually reach a point where some part of it is constrained by de/serialization.

Not much is faster than protobuf except for zero copy formats.

theamk2• 8 months ago

ASN.1 has too much stuff. The moment you write "I made ASN.1 decoder/encoder", someone will throw TeletexString or BMPString at it. Or inheritance, as morshu9001 sad. So at this point:

- You can support all those features, and your ASM.1 library will be horribly bloated and over-engineered.

- You can support your favorite subset, but then you cannot say it's ASN.1 anymore. It will be "ASN.brabel", which only has one implementation (yours). And who wants that?

(unless you are Google and have immense developer influence... But in this case, why not design things from scratch, since we are making all-new protocol anyway?)

themafia3• 8 months ago

someone will throw TeletexString or BMPString

ASCII with escapes and UCS-2.

horribly bloated and over-engineered.

It's no more or less complicated than XML, JSON or CSV. Which is why you can use ASN.1 to serialize to and from all these formats. ASN.1 provides you an additional level of schema above these. It simply allows you to describe your problem.

I find ASN.1 far more sane and useful than something like JSON Schema which is just as "bloated and over-engineered." It turns out describing data is not a simple problem.

adastra22• 8 months ago

ASN.1 is a nightmare, and I would never use it for a greenfield project.

cryptonector23• 8 months ago

I... wouldn't use it for a greenfield project either unless I got good at porting Luke Howard's Swift ASN.1 stack to whatever language I might be using that isn't C. For C I'd just use Heimdal's awesome ASN.1 compiler and be done. Even then I would be tempted to use flatbuffers instead, or else I'd have to go implement OER (a bunch of work I don't really care to do).

The problem with ASN.1 -- the only real problem with ASN.1, is lack of excellent tooling.

cryptonector23• 8 months ago

Thank you! Now I don't have to be the one saying this. Props if you use OER over DER. But since OP needs available tooling they might as well go to flatbuffers, which is much better than PB much like OER is much better than DER.

IshKebab2• 8 months ago

I don't see how you can seriously criticise Protobuf's very simple encoding scheme as being too complex while recommending ASN.1!!

Totally mad.

wilg• 8 months ago

One of the best parts of Protobuf is that there's a fully compatible JSON serialization and deserialization spec, so you can offer a parallel JSON API with minimal extra work.

bglusman2• 8 months ago

Yes! Came to comments to see if that was discussed/commented on above with link: https://protobuf.dev/programming-guides/json/

pyrolistical• 8 months ago

Compressed JSON is good enough and requires less human communication initially.

Sure it will blow up in your face when a field goes missing or value changes type.

People who advocate paying the higher cost ahead of time to perfectly type the entire data structure AND propose a process to do perform version updates to sync client/server are going to lose most of the time.

The zero cost of starting with JSON is too compelling even if it has a higher total cost due to production bugs later on.

When judging which alternative will succeed, lower perceived human cost beats lower machine cost every time.

This is why JSON is never going away, until it gets replaced with something with even lower human communication cost.

esafak2• 8 months ago

It won't go away in the same way COBOL won't. That does not mean we should be using it everywhere for greenfield projects.

DyslexicAtheist• 8 months ago

People who advocate paying the higher cost ahead of time to perfectly type the entire data structure AND propose a process to do perform version updates to sync client/server are going to lose most of the time.

that's true. But people also rather argue about security vulnerabilities than getting it right from the get-go. Why spend an extra 15 mins effort during design when you can spend 3 months revisiting the ensuing problem later.

jstanley• 8 months ago

Alternatively: why spend an extra 15 mins on protobuf every other day, when you can put off the 3-month JSON-revisiting project forever?

morshu900116• 8 months ago

I've gone the all-JSON route many times, and pretty soon it starts getting annoying enough that I lament not using protos. I'm actually against static types in languages, but the API is one place they really matter (the other is the DB). Google made some unforced mistakes on proto usability/popularity though.

almosthere2• 8 months ago

why are you against static types in languages?

I once converted a fairly large JS codebase to TS and I found about 200 mismatching names/properties all over the place. Tons of properties we had nulls suddenly started getting values.

barremian3• 8 months ago

When judging which alternative will succeed, lower perceived human cost beats lower machine cost every time.

Yup this is it. No architect considers using protos unless there is an explicit need for it. And the explicit need is most times using gRPC.

Unless the alternative allows for zero cost startup and debugging by just doing `console.log()`, they won't replace JSON any time soon.

Edit: Just for context, I'm not the author. I found the article interesting and wanted to share.

duped3• 8 months ago

Print debugging is fine and all but I find that it pays massive dividends to learn how to use a debugger and actually inspect the values in scope rather than guessing which are worth printing. It also is useless when you need to debug a currently running system and can't change the code.

And since you need to translate it anyway, there's not much benefit in my mind to using something like msgpack which is more compact and self describing, you just need a decoder to convert to json when you display it.

theshrike792• 8 months ago

Also: debugging

You (a human) can just open a JSON request or response and read what's in it.

With protobuf you need to build or use tooling that can see what's going on.

generativenoise• 8 months ago

It is only "human readable" since our tooling is so bad and the lowest common denominator tooling we have can dump out a sequence of bytes as ascii/utf-8 text somewhat reliably.

One can imagine a world where the lowest common denominator format being a richer structured binary format where every system has tooling to work with it out of the box and that would be considered human readable.

taco_emoji• 8 months ago

i really hate this blog post format of posting the new thing you discovered as if it's objectively better than the previous thing. no it's not, you just like it better, which is FINE, just own it

morshu900116• 8 months ago

Protos are great. Last time I did a small project in NodeJS, I set up a server that defines the entire API in a .proto and serves each endpoint as either proto or json, depending on the content header. Even if the clients want to use json, at least I can define the whole API in proto spec instead of something like Swagger.

So my question is, why didn't Google just provide that as a library? The setup wasn't hard but wasn't trivial either, and had several "wrong" ways to set up the proto side. They also bait most people with gRPC, which is its own separate annoying thing that requires HTTP/2, which even Google's own cloud products don't support well (e.g App Engine).

P.S. Text proto is also the best static config language. More readable than JSON, less error-prone than YAML, more structure than both.

noctune• 8 months ago

You might be interested in https://connectrpc.com/. It's basically what you describe, though it's not clear to me how well supported it is.

morshu900116• 8 months ago

Yeah that one looked good. I don't remember why I didn't use it that time, maybe just felt it was easy enough to DIY that I didn't feel like using another dep (given that I already knew express and proto in isolation). The thing is, Google themselves had to lead the way on this if they wanted protobuf to be mainstream like JSON.

c-cube• 8 months ago

That's what Twirp (https://github.com/twitchtv/twirp) is about. Protobuf or JSON, over any HTTP, with a simple URL schema. It's fairly simple.

rileymichael• 8 months ago

highly recommend twirp, even in current year. connectrpc seems to have stalled so there isn't a ton of languages w/server support, and because of the grpc interop on top of their own protocol it's a bit of an undertaking to roll your own.

the twirp spec however is so simple you can throw together your own code generator in an afternoon for whatever language you want.

jtrn• 8 months ago

I like Python-like indentation, but I usually read Python in an IDE or code blocks. JSON in a non-monospace environment might be problematic with some fonts. Hell, I pass JSON around in emails and word processors all the time.

wg0• 8 months ago

Protos don't work out of the box in any browsers as far as I checked last time unless you're willing to deploy a proxy in front to do the translation and it requires extra dependency on the browser as well.

Plus - tooling.

JSON might not be simpler or strict but it gets the job done.

If JSON's size or performance is causing you to go out of business, you surely have bigger problems than JSON.

taftster• 8 months ago

Right, I find the use of protobuf lacking with direct support in the browser. Since JSON is a native data encoding format of the browser (effectively), it's just easier to have a JSON-based API.

Yes, there are abstractions or other hacks that would bolt on protobuf support in the browser, but that's not ideal in my mind.

Protobuf is an ideal exchange format when you're not dealing with the public as a whole. That is, a private or corporate API for your data processing pipelines, etc.

dhussoe4• 8 months ago

I like that JSON parsing libraries (Serde etc.) allow you to validate nullability constraints at parse-time. Protobuf's deliberate lack of support for required fields means that either you kick that down to every callsite, or you need to build another parsing layer on top of the generated protobuf code.

Now, there is a serde_protobuf (I haven't used it) that I assume allows you to enforce nullability constraints but one of the article's points is that you can use the generated code directly and:

No manual validation. No JSON parsing. No risk of type errors.

But this is not true—nullability errors are type errors. Manual validation is still required (except you should parse, not validate) to make sure that all of the fields your app expects are there in the response. And "manual" validation (again, parse don't validate) is not necessary with any good JSON parsing library, the library handles it.

myvoiceismypass• 8 months ago

'Parse, don't validate' is such great reading: https://lexi-lambda.github.io/blog/2019/11/05/parse-don-t-va...

recursivecaveat• 8 months ago

My dream binary format is schema driven, as compact and efficient as Capt Proto or such, but just optionally embeds the entire schema into the message. Then we can write a vim plugin that just opens the file in human readable form without having to fish for the schema. Whenever I am using binary formats, it's because I have a list of millions of objects of the same types. Seems to me that you may as well tack 1KB of schema onto a 2GB message and make it self-describing so everyone's life is easier.

barremian3• 8 months ago

You could have a look at Avro (https://avro.apache.org/) and Yardl (https://microsoft.github.io/yardl/).

EdwardDiego• 8 months ago

As another user suggested, Avro is something to look into.

HelloNurse4• 8 months ago

For many web services it would be more often 200 KB of schema (many possible request and responses, some of them complex) tacked onto a less than 1 KB message (brief requests and acknowledgements without significant data inside).

squirrellous2• 8 months ago

It’s possible to build this around protobuf. Google has a rich internal protobuf ecosystem that does this and supports querying large amounts of protobuf data without specifying schemas. They are only selectively open sourced. Have a look at riegeli if you are interested.

https://github.com/google/riegeli

coffeeaddict1• 8 months ago

protobuf

As an aside, like all things Google, their C++ library is massive (14mb dll) and painful to build (takes nearly 10 minutes on my laptop).

mb7733• 8 months ago

Yeah and (1) the codegen produces massive headers that slow compilation of anything that touches them (2) the generated classes are really awkward to use. Not a big fan of the experience of protobuffer generated code in a large C++ code base.

It's lead to a huge layer of adapters and native c++ classes equivalent to the protobuffers classes to try and mitigate these issues.

keithnz• 8 months ago

CBOR is a pretty good middle ground

teleforce• 8 months ago

Kudos to the poster and the author of this article. I think this is by far the most insightful technical post I've read this year on HN.

If you develop or use an API, there’s a 99% chance it exchanges data encoded in JSON.

Just wondering if the inherent defiencies of JSON can somewhat be improved by CUE lang since the former is very much pervasive and the latter understand JSON [1],[2].

[1] Configure Unify Execute (CUE): Validate, define, and use dynamic and text‑based data:

https://cuelang.org/

[2] Cue – A language for defining, generating, and validating data:

https://news.ycombinator.com/item?id=20847943

Joel_Mckay• 8 months ago

BSON dealt with a lot of the JSON limitations, and ambiguous type issues.

Batching with message pooling to a transaction payload size limit actually made it performant. =3

loph• 8 months ago

How many times has this problem been "solved"?

https://en.wikipedia.org/wiki/DCE/RPC

DCE/RPC worked in 1993, and still does today.

Protocol buffers is just another IDL.

PantaloonFlames3• 8 months ago

DCE STILL WORKS?

Where!??

JoshMock• 8 months ago

Protobuf is a great format with a lot of benefits, but it's missing one that I wish it could support: zero-copy. The ability to transport data between processes, services and languages with effectively zero time spent on serialization and deserialization.

It appears possible in some cases but it's not universally the case. Which means that similar binary transport formats that do support zero-copy, like Cap'n Proto, offer most or all of the perks described in this post, with the addition of ensuring that serialization and deserialization are not a bottleneck when passing data between processes.

jonny_eh• 8 months ago

Is that a format/serialization issue, or library/implementation issue?

__s• 8 months ago

Format: https://news.ycombinator.com/item?id=23589117

ElectricalUnion• 8 months ago

Serialization issue. From the Introduction to Cap’n Proto:

"Cap’n Proto is INFINITY TIMES faster than Protocol Buffers. (...) there is no encoding/decoding step. The Cap’n Proto encoding is appropriate both as a data interchange format and an in-memory representation, so once your structure is built, you can simply write the bytes straight out".

I take it as a rationalization of what OLE Compound File Binary - internal Microsoft Office memory structures serialized "raw" as file format - would look like if they paid more attention to being backward and forward compatible and extensible.

pornel• 8 months ago

It depends how you actually use the messages. Zero-copy can be slowing things down. Copying within L1 cache is ~free, but operating on needlessly dynamic or suboptimal data structures can add overheads everywhere they're used.

To actually literally avoid any copying, you'd have to directly use the messages in their on-the-wire format as your in-memory data representation. If you have to read them many times, the extra cost of dynamic getters can add up (the format may cost you extra pointer chasing, unnecessary dynamic offsets, redundant validation checks and conditional fallbacks for defaults, even if the wire format is relatively static and uncompressed). It can also be limiting, especially if you need to mutate variable-length data (it's easy to serialize when only appending).

In practice, you'll probably copy data once from your preferred in-memory data structures to the messages when constructing them. When you need to read messages multiple times at the receiving end, or merge with some other data, you'll probably copy them into dedicated native data structs too.

If you change the problem from zero-copy to one-copy, it opens up many other possibilities for optimization of (de)serialization, and doesn't keep your program tightly coupled to the serialization framework.

squirrellous2• 8 months ago

I don’t understand this argument. It seems to originate from capnp’s marketing. Capnp is great, but the fact that protobuf can’t do zero copy should be more an academic issue than practical. Applications that want to use a schema always needs their own native types that serialize and deserialize from binary formats. For protobuf you either bring your own or use the generated type. For capnp you have to bring your own. So a fair comparison of serialization cost would compare:

native > pb binary > native

native > capnp binary > native

If you benchmark this, the two formats are very close. Exact perf depends on payload. Additionally, one could write their own protobuf serializer with protoc they really need to.

brunoluiz• 8 months ago

I am curious why the author did not consider ConnectRPC (http://connectrpc.com/), which could be a great middle ground since it is compatible with both Protobuf and JSON served APIs. It is developed by Buf, which has been a leader Protobuf tooling.

dfabulich• 8 months ago

With JSON, you often send ambiguous or non-guaranteed data. You may encounter a missing field, an incorrect type, a typo in a key, or simply an undocumented structure. With Protobuf, that’s impossible. Everything starts with a .proto file that defines the structure of messages precisely.

This deeply misunderstands the philosophy of Protobuf. proto3 doesn't even support required fields. https://protobuf.dev/best-practices/dos-donts/

Never add a required field, instead add `// required` to document the API contract. Required fields are considered harmful by so many they were removed from proto3 completely.

Protobuf clients need to be written defensively, just like JSON API clients.

klysm• 8 months ago

It’s also conflating the serialization format with contracts

shortrounddev2• 8 months ago

Most web frameworks do both at the same time to the point where having to write code which enforced a type contract after deserializing is a delabreaker for me. I eant to be able to define my DTOs in one place, once, and have it both deserialize and enforce types/format. Anything else is code smell

ablob3• 8 months ago

I feel like that's fine since both things go hand in hand anyway. And if choosing the JSON-format comes with a rather high amount of contract-breaches it might just be easier to switch that instead of fixing the contract.

cookiengineer• 8 months ago

Isn't the core issue just language and implementation differences of clients vs servers here?

I went all in with Go's Marshalling concept, and am using my Gooey framework on the client side nowadays. If you can come around Go's language limitations, it's pretty nice to use and _very_ typesafe. Just make sure to json:"-" the private fields so they can't be injected.

[1] shameless drop https://github.com/cookiengineer/gooey

bloppe4• 8 months ago

Skew is an inherent problem of networked systems no matter what the encoding is. But, once the decoding is done, assuming there were no decoding errors in either case, at least with protobuf you have a statically typed object.

You could also just validate the JSON payload, but most people don't bother. And then they just pass the JSON blob around to all sorts of functions, adding, modifying, and removing fields until nobody knows for sure what's in it anymore.

happymellon2• 8 months ago

You could also just validate the JSON payload, but most people don't bother.

I don't think I have ever worked somewhere that didn't require people to validate inputs.

The only scenario could be prototypes that made it to production, and even when its thrown over the wall I'll make it clear that it is unsupported until it meets minimum requirements. Who does it is less important than it happening.

Ghoelian• 8 months ago

The convention at every company I've worked at was to use DTO's. So yes, JSON payloads are in fact validated, usually with proper type validation as well (though unfortunately that part is technically optional since we work in php).

Usually it's not super strict, as in it won't fail if a new field suddenly appears (but will if one that's specified disappears), but that's a configuration thing we explicitly decided to set this way.

HelloNurse4• 8 months ago

The blog seems to contain other similar misunderstandings: for example the parallel article against using SVG images doesn't consider scaling the images freely a benefit of vector formats.

chrismorgan3• 8 months ago

https://aloisdeniel.com/blog/i-changed-my-mind-about-vector-... seems fairly clearly to be talking about icons of known sizes, in which case that advantage disappears. (I still feel the article is misguided and that the benefit of runtime-determined scaling should have been mentioned, and see no benchmarks supporting its performance theses, and I’d be surprised if the difference was anything but negligible; vector graphic pipelines are getting increasingly good, and the best ones do not work in the way described, and could in fact be more efficient than raster images at least for simpler icons like those shown.)

gipp• 8 months ago

I think the OP meant something far simpler (and perhaps less interesting), which is that you simply cannot encounter key errors due to missing fields, since all fields are always initialized with a default value when deserializing. That's distinct from what a "required" field is in protobuf

orphea2• 8 months ago

Depending on the language/library, you can get exactly the same behavior with JSON.

Pet_Ant• 8 months ago

Protobuf clients need to be written defensively, just like JSON API clients.

Oof. I'd rather just version the endpoints and have required fields. Defensive is error-prone, and verbose, harder to reason about, and still not guaranteed. It really feels like an anti-pattern.

_heimdall• 8 months ago

I need to dig deeper into Protobuf. I've never quite understood the benefit of Protobug over XML.

_el1s7• 8 months ago

Why I stopped caring about "Why I stopped [insert something widely used here]" click bait articles

PunchyHamster• 8 months ago

"I've used this optimization technique to make app faster"

The app 20req/sec

The app after optimizations: 20req/sec (It waits for db query anyway)

PantaloonFlames3• 8 months ago

Yes. Proto makes sense when the request rate is much higher and the network is constrained.

Otherwise, json is sufficient.

kragen5• 8 months ago

If it's the network that's constrained and not the CPU, gzipped JSON will often beat protobufs.

bzmrgonz• 8 months ago

What about TOON op? I understand that's the standard poised to takeover from Json. Your thoughts??

beders• 8 months ago

Know the consumer of your API.

If that is just your team, use whatever tech gets you there quick.

However, if you need to provide some guarantees to a second or third party with your API, embrace standards like JSON, even better, use content negotiation.

socalgal22• 8 months ago

https://github.com/ajv-validator/ajv

138 million downloads from npm in the last week. Yes, you can validate your JSON

cryptonector23• 8 months ago

If you're gonna switch from JSON to... PB, then you might as well switch to flatbuffers before you realize it's better than PB and save yourself a lot of trouble.

lenkite• 8 months ago

There is no mention in this thread of how the author is using Dart and Shelf for his REST API's. Code is rather readable and elegant. This is not a combo I have every tried before. Does anyone have any experience of how it compares versus REST services written in Go/Rust/Python ?

lazy_afternoons• 8 months ago

IIRC from the red wild boar book, JSONs biggest win is that it got the adoption.

Getting everyone to agree on a standard was/is/will be the tougher part.

rock_artist• 8 months ago

I feel few points weren’t addressed in the article.

1. Size, biggest problem with JSON can happen when things gets too big. So here other formats might be better. Yet, as a reminder JSON has the binary version named BSON.

2. Zero batteries. JSON is readable by humans but also almost self explanatory format. Most languages has built in or quick drop in for json. Still, it’s easy to implement a limited JSON parser from scratch when in need (eg. Pure on func in C on a tiny device).

Working with Protobuf and MsgPack in the past, You have much more tooling involved especially if data passes between parts written in different languages.

3. Validation, JSON is simple. But there are solutions such as JSON Schema.

paulddraper2• 8 months ago

BSON is not simply a binary encoding of JSON.

It is a JSON superset with binary encoding, created by MongoDB. (And there is even a JSON encoding of BSON, called extended JSON.)

AFAIK there is no widely adopted binary pure adaptation of JSON. (There are application-specific storage formats, like PostgreSQL JSONB, or SQLite JSONB.)

——-

Moreover, JSON is relatively compact. BSON or other self descriptive binary formats are often around the same size of JSON. MessagePack aggressively tries to be compact and is, depending on the data. BSON doesn’t try to be compact, rather it improves the parse speed.

WorldMaker2• 8 months ago

CBOR [0] is probably the closest to a widely adopted "pure" adaptation of JSON. It is still technically a superset of JSON, but it tries to be closely matched and frequently cross-references the JSON specs directly, especially because it is also an IETF tracked standard like JSON, and in so far as widely adopted is concerned is included in web standards like WebAuthn today. (For instance, you can't handle Passkeys without some amount of CBOR. The presumed next steps to wider adoption now that all browsers have internal CBOR encoders/decoders would be to add a web platform JS API for it as well.)

However, yes, JSON compresses extremely well even in ancient gzip, but especially in Brotli, and desiring compaction of your API responses alone isn't necessarily the best reason to prefer a binary encoding of JSON to just using JSON and letting compression do its thing.

[0] https://www.rfc-editor.org/rfc/rfc8949.html

ansgri• 8 months ago

Compressed jsonlines with strong schema seems to cover most cases where you aren't severely constrained by CPU or small message size (i.e., mostly embedded stuff).

davedx• 8 months ago

"Ultra-efficient"

Searched the article, no mention of gzip, and how most of the time all that text data (html, js and css too!) you're sending over the wire will be automatically compressed to...... an efficient binary format!

So really, the author should compare protobufs to gzipped JSON

chillfox• 8 months ago

Last time I was evaluating different binary serialization formats for an API I was really hoping to get to use one of the cool ones, but gzipped JSON just beat everything and it wasn't even close.

theshrike792• 8 months ago

There are some compression formats that perform better than gzip, but it's very dependent on the data you're compressing and your timing requirements (is bandwidth or CPU more important to conserve).

But in the end compressed JSON is pretty good. Not perfect, but good enough for many many things.

MangoToupe• 8 months ago

I would think that serialization/deserialization time would be the largest drawback of json (at least for serving APIs). Pretty much all the other pain points can slowly be ironed out over time, albeit with deeply ugly solutions.

thayne2• 8 months ago

It depends on what your data looks like. If your content is mostly UTF-8 text, with dynamic keys, then I wouldn't expect protobuf to have much of an advantage over JSON for parsing to an equivalent structure. On the other hand, if you have binary data that needs to be base64 encoded in JSON, then protobuf has a significant advantage.

bloppe4• 8 months ago

https://auth0.com/blog/beating-json-performance-with-protobu...

tmikaeld• 8 months ago

So a potential 4-9% difference..

NOT worth it, especially if the whole infra is already using JSON.

andersmurphy• 8 months ago

Or streaming brotli/zstd json/html where the compression window can be used for the duration of the connection.

akoboldfrying• 8 months ago

But in that case the server/CDN won't be able to cache the gzipped forms of the individual files -- so probably a win for highly dynamic/user-specific content, but a loss for static or infrequently generated content.

WorldMaker2• 8 months ago

Brotli also benefits out-of-the-box in fresh compression windows with some common JSON patterns always in the Brotli static dictionary.

JodieBenitez• 8 months ago

This is so obvious to me... JSON vs. JSON + mod_deflate is just night and day.

orphea2• 8 months ago

Do you compress data if it's then encrypted (HTTPS)?

https://en.wikipedia.org/wiki/CRIME

coolThingsFirst• 8 months ago

How on earth would gzipping larger amount of data be more efficient than gzipping smaller amount of data?

ablob3• 8 months ago

It's a question of entropy. Data is rarely truly random and for larger data there is a lot higher chance of having this "unrandomness" occur.

If your data consists of 4 kilobytes of just 00_01, then you gain a lot by just remembering:

  "write 00_01 2000 times".

Conversely, if the small amount of data is 00_01_00_01_00_01 then using the previous format would yield:

  "write 00_01 3 times"

As you can see, it does not nearly save as much space in comparison with the original data, hence it's less efficient to use the format. The specifics are highly dependent on the compression algorithmm used so take the example with a grain of salt, but I hope it gets the basic idea of why it can be more efficient across.

sergiotapia• 8 months ago

Personally, I looked into protobuf for our Elixir/React Native wombocombo but the second I realized we would have to deploy app updates when we added or removed a field from the response structure it became a non-starter.

I can't imagine using protobuf when you're in the first 5 years of a product.

xarope• 8 months ago

I'm pretty sure protobuf ignores new fields (if you add; assuming you add as an append, and not change the field ordering), and it recommends you not to remove a field to ensure backward compatibility.

gethly• 8 months ago

Reading the first few paragraphs and immediately seeing PB made me instantly think of "Every master was once a beginner.".

When you'll go through your own journey, and inevitably end back with json, do write another blog post :) ... we've all been there.

umvi• 8 months ago

Protobufs are a pain to debug and maintain compared to json and modern browsers support zstd compression making json "efficient"

undefeated• 8 months ago

Complaining about JSON and then proceeding to write your API in Dart is... interesting.

zabil• 8 months ago

I have a slight dislike for JSON+REST for API's.

The design overhead involved in determining the correct URL and HTTP method adds a layer of subjectivity to the design and bike shedding arguments.

I’m not a huge fan of Protobuf/GRPC either, if there’s a better alternative I believe RPC is the right approach for exposing APIs.

globular-toast• 8 months ago

An API (Application Programming Interface) is a set of rules that allow two systems to communicate. In the web world, REST APIs ... are by far the most widespread.

I too had this overly restrictive view of "APIs" for too long. One I started to think about it as the interface between any teo software components it really changed the way I did programming. In other words, a system itself is composed and that composition is done via APIs. There's no point treating "the API" as something special.

cheema33• 8 months ago

I use GraphQL. It has a higher learning curve. But it addresses the shortcomings listed by the referenced blog article. It offers type safety, efficiency and modern tooling. And it is also human readable.

If you use good tooling, you can have a mutation change a variable type in the database and that type change is automatically reflected in the middleware/backend and the typescript UI code. Not only that libraries like HotChocolate for asp.net come with built-in functions for filtering, pagination, streaming etc.

knallfrosch• 8 months ago

I have never encountered the use case where the data sent by the backend over the normal CRUD operations was the bottleneck.

But we have built protobuf into a web server that handles 2 requests per second. Why? We wanted to learn about it on the job.

I think that's 99% of Protobuf usage.

mjmas• 8 months ago

The same message in Protobuf binary
→ About 23 bytes.

This appears to be a nice ai-generated result. There are already at least 23 bytes of data there (number 42 (1 byte) + string of 5 chars + string of 17 chars + 1 boolean), so that plus field overhead will be more.

liampulles• 8 months ago

I know that OpenAPI code gen support is spotty, and that protobuf codegen (in my experience) is quite good, but all of this starts from the idea that the SaaS I'm consuming has actually documented their API properly.

A sizable portion of the integrations I've built have had to be built by hand, because there are inevitable stupid quirks and/or failures I've had to work around. For these usecases, using JSON is preferable, because it is easy for me to see what I have actually been sent, not what the partially up to date spec says I should've been sent.

This is consistent with the idea that communication over the internet should consist of (encrypted and compressed) plain text. It's because human beings are going to have to deal with human reality at the end of the day.

pjacotg• 8 months ago

On the human readability concern, we use protobuf converted to text format. It looks JSON like so very readable and comes with all the other benefits of protobuf.

whatevaa3• 8 months ago

I can use text based API's (like with JSON) with nothing else but text editor and curl. No other tooling actually required. Meanwhile if binary protocol tooling in your stack sucks, then it just sucks.

Had the joy of implementing calling SOAP service with client generated from wsdl in .net core 2/3 times. Tooling was shit poorly undocumented amd with crappy errors at that time. Run only with very specific versions in very specific way. And not much you can do about it, rolling your own SOAP client would be too expensive for our team.

REST with JSON meanwhile is easy and we do it all the time, don't need any client, just give us request/response spec and any docs.

borplk• 8 months ago

If you have a protobuf API, does it work in the js environment of browsers? Last time I checked (many years ago) the browser story wasn't good.

baquero• 8 months ago

If you want to work with ProtoBuf as with other APIs, have a look at https://github.com/qaware/protocurl

protobuf-ai• 8 months ago

I started working with protobuf on a project, and just went down the path of MCP. If anybody would like to try it out, it's here: https://www.protobuf.ai/. Just a lightweight MCP server for schemas that plugs into a schema registry.

madFlasher• 8 months ago

The author should check first the performance of protobuf serialization/deserialiazation in browsers

Due to very native nature of JSON in browsers and node backend it usually also the fastest data format

If for example you have C++ on backend and C++ on frontend - you'll definitely have some performance boost

But for browsers usage the goal is not so obvious

asa400• 8 months ago

Whenever people bring up binary formats I have to bring up Erlang External Term Format (ETF)[0].

It's the native format Erlang nodes use to serialize data to communicate with each other, but it's just a simple Type-Length-Value binary format, so anything can implement it.

It's small enough that you can create a reasonably complete and fast implementation of it for your language in an afternoon. It's self-describing, so if you can read ETF you can read any ETF message, as there are no out of band schemas. I love it.

[0] https://www.erlang.org/doc/apps/erts/erl_ext_dist.html

wallaconno• 8 months ago

My criticism is that protobuf is a premature optimization for most projects. I want to love protobuf, but it usually slows down my development pace and it’s just not worth it for most web / small data projects.

Distributing the contract with lock-step deploys between services is a bit much. JSON parsing time and size are not usually key factors in my projects. Protobuf doesn’t pose strict requirements for data validation, so I have to do that anyway. Losing data readability in transit is a huge problem.

Protobuf seems like it would be amazing in situations where data is illegible and tightly coupled such as embedded CAN or radio.

stanfordkid• 8 months ago

They didn't even mention MessagePack. Also there is a huge amount of developer over-head for using things like ProtoBuf. You can always validate your API responses with Zod or JSONSchema so that is a bit of a moot point!

firemelt• 8 months ago

this article makes me keep json

Why I stopped using JSON for my APIs

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