It IS simpler to use text - He claims "Text was never as portable as it's believed to be.", but ascii/unicode are probably the most portable formats we've ever created. I can't think of a computer that won't be able to parse and display one of those two formats (From embedded hardware, to old f16 parts, to my modern laptop, to the raspberry pi, to the fucking computer I designed in my EE classes).
Being able to type out messages is hugely helpful while debugging and developing (I copy and paste things that look exactly like the code he claims no one would ever write - It's like he doesn't understand the value of a clipboard, or a text editor I can dump a message into and change a single value in - Something I can conveniently do on pretty much any system ANYWHERE without having to install any extra software if the format is text)
His parsing example is hilarious - See that readable text above? Psh, Folly! That's hard to read so lets use specialized tools that depend entirely on system specific details and configuration (Int size, byte order, struct packing, etc) and claim that's better!
Extensibility, meh - I find this one rarely matters as much as people believe it does, but to me, the big benefit of text is that I can easily craft messages with new fields myself without having to write code to do it.
Error recovery... I can sort of agree (in transit over a noisy channel, use a format that supports ECCs) but he misses that there are two different types of error here - An unexpected field value/type, and a generally malformed payload.
The first will break binary but not something like a json parser. The second will break both (he only talks about the second, since he assumed the failure happens at tokenization time...)
Basically - My whole point devolves into "It sure seems like he's arguing for premature optimization".
If you have a spot where text is particularly expensive or inefficient, suck it up and move to a binary protocol that requires more documentation, tooling, and work. Everywhere else... it seems like a bad move.
Just a few weeks ago when I needed to peek into some StatsD packets to ensure we were sending what we expected when monitoring wasn't working. If it was a binary format this simply would not have been an option as this was a remote environment with limited tooling available to it.
You are only a small fractional part of the entire life of the protocol. Protocol designs largely impact hardware design and requirements. A binary protocol will safely work on a micro-controller without too much effort while a text based protocol requires some serious CPU juice, code storage space and volatile memory to get it off the ground.
Sure, text will work on most devices, but the parsers for those text based protocols become excessively complex. There is some ideas floating on in the field of "green" computing where its becoming increasingly imperative to do more processing per watt. Text parsers will certainly not fit into that bill.
> new fields myself without having to write code to do it.
Then what's the point of that new field if there's no code to handle it? That said, CBOR and TLV is similar too -- in that, you can add new fields without any code to handle it. But what good is it?
> An unexpected field value/type, and a generally malformed payload.
Content-Length: bad-string
Continuing the hilarity...
> That's hard to read so lets use specialized
Is it CR? Is it LF? Is it CRLF? Did I configure my text editor to use the correct line terminator? Does my clipboard reset the CRLF to CR or LF? Oh, wait is that a space (0x20) or tab (0x09) there? Hmm.. never mind.
Also,
From: 1234<1234@example.org>;branch=abcd1234
From: 1234<1234@example.org;branch=abcd1234>
It's not by any means exclusive to text-based protocols, but there's this tendency to assume everything about a text-based protocols is ‘obvious’, ‘self-documenting’ and doesn't need specifying, and to think that just because the individual elements of the protocol are human-readable, this will somehow magically make the computers using the protocol follow the Gricean maxims (if it doesn't make sense, nobody will ever say that, therefore I don't need to think about it).
I used to see Postel's Law ("be conservative in what you send, be liberal in what you accept") quoted as some sort of antidote, but it seems to have fallen out of fashion -- I think enough people saw how that ideal played out in reality. Nowadays a JSON library feels justified throwing a fit if it sees a comment string instead of playing along with such shenanigans.
> It's not by any means exclusive to text-based protocols
Plus, I would argue text-based greatly increases the surface area for ambiguity, whereas, for instance, there are only a few ways a sane person would send an integer as bytes.
Integer encoding (as opposed to e.g. encoding of opaque binary strings) actually appears to be a bad example to me: various universal binary encoding protocols, self-describing or not, have an astounding number of unsigned and signed integer encodings among them. It’s like inventing a new one is a rite of passage or something.
It's really really hard to write an unambiguous text protocol specification and equally hard to write something that implements it properly. Think about all the extra ambiguities text adds: where is whitespace allowed? How are newlines encoded? Are windows line endings ok? Does case matter? Which bits are ASCII and which are UTF-8? How are values quoted?
It's just insanely more complicated, and there are many subtle differences that seem reasonable to different people. "Of course whitespace is allowed there!"
It makes everything way less robust and way more prone to quirks-mode style degradation.
sigh Those are not "Windows line endings". CRLF has been used as a line-delimiter in every single ASCII-based network protocol since 1971 to this day. UNIX is not the single progenitor of every thing in the modern computing, not by a long shot.
Nope, you may still need to call ntoh/hton, depending on how the compiler you use orders the bitfields inside an int. Plus you need "__attribute__((packed))" or whatever the compiler you use supports to make that C struct definition mean what it looks like it means: even then I am not sure those three bitfields are required to occupy exactly 8 bits.
typedef struct { unsigned char data[2]; } u16be_t;
inline static uint16_t get_u16be(const u16be_t *p) {
uint16_t result = 0;
result |= (uint16_t) p->data[0] << 8;
result |= (uint16_t) p->data[1];
return result;
}
inline static void put_u16be(u16be_t *p, uint16_t value) {
p->data[0] = value >> 8;
p->data[1] = value;
}
I think another big reason text-based protocols are seductive is that they're an engineering path of least resistance. When you start off text-based, how to debug and analyze and interoperate with other implementations can be put off for later, or be Someone Else's Problem. Whereas if you design the same protocol but in binary, these tricky considerations are harder to ignore -- even though text-based protocols will still run into the same problems eventually, because there's no way I'm typing in a Cookie header by hand or decoding Base64 in my head.
Was it? By my reading there was way more weird stuff than there is today but I certainly wasn't alive back then.
[0] https://en.wikipedia.org/wiki/World_Wide_Web#/media/File:NeX...
[1] https://en.wikipedia.org/wiki/Simple_Mail_Transfer_Protocol#...
