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Sqids – Generate short unique IDs from numbers

sqids.org

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Re: Sqids – Generate short unique IDs from numbers

#91

Post by arp242 »

runlevel1 wrote: post #51
habitue wrote: post #33

Skipping profanity seems like a liability in this design. It means in order to preserve the encoding you need to make the banned word list immutable, otherwise old sqids will decode to the wrong thing when you get them back.

The stupid simple way I did this ages ago was: 1. Start with a-z. 2. Drop all vowels, numbers, most homoglyphs, and the letter 'x'. 3. Map digits 0-9 to one of the remaining letters. 4. Stringify the integer and replace the digit in each decimal place with its corresponding character. For my use-case, all the numbers were >7 digits long, so the odds of you getting an offensive acronym were reasonably low unless you s…

Many of those reviewer comments are utterly moronic. And that is my polite opinion.

How does this work? Is there a review board? Is it put to public review? A few of them like "dick out" and "shtlord" are reasonable, but many of them seem so bonkers it looks like the work of trolls.

Anyway, TIL that 1970s Intel was a MS-13 gang outfit and that Octocat really means "eight vaginas".

Re: Sqids – Generate short unique IDs from numbers

#92

Post by lights0123 »

fimdomeio wrote: post #40
Etheryte wrote: post #37

Earlier quoted context omitted.

I don't think this holds, you can enforce filtering in the encoding step, i.e. be strict about what you output, but always decode, even if the input is profanity. This means you can also be backwards compatible if you update the list etc. So in short, the old maxim of be strict about your outputs and lenient about your inputs.

From their FAQ: "The best way to ensure your IDs stay consistent throughout future updates is to provide a custom blocklist, even if it is identical to the current default blocklist."

The *encoding* changes. The decoding stays consistent:

> Decoding IDs will usually produce some kind of numeric output, but that doesn't necessarily mean that the ID is canonical. To check that the ID is valid, you can re-encode decoded numbers and check that the ID matches.

The reason this is not done automatically is that if the default blocklist changes in the future, we don't want to automatically invalidate the ID that has been generated in the past and might now be matching a new blocklist word.

Re: Sqids – Generate short unique IDs from numbers

#93

Post by air7 »

runlevel1 wrote: post #51
habitue wrote: post #33

Skipping profanity seems like a liability in this design. It means in order to preserve the encoding you need to make the banned word list immutable, otherwise old sqids will decode to the wrong thing when you get them back.

The stupid simple way I did this ages ago was: 1. Start with a-z. 2. Drop all vowels, numbers, most homoglyphs, and the letter 'x'. 3. Map digits 0-9 to one of the remaining letters. 4. Stringify the integer and replace the digit in each decimal place with its corresponding character. For my use-case, all the numbers were >7 digits long, so the odds of you getting an offensive acronym were reasonably low unless you s…

> California Personalized License Plate Requests Flagged for Review 2015-2016: https://docs.google.com/spreadsheets/d/18IUVU9Q4uN_lxqNd5AsN...

Wow this is a funny peek into a weird perdicment where people need to justify that they have a good reason to have a specific license plate.

Some seems obviously ok such as:

INT13H

314 PI

And some are obviously not:

DRY(hand emoji)JOB

DICK OUT

Come to think of it: Can license plates have emojis now?!

Re: Sqids – Generate short unique IDs from numbers

#95

Post by 8n4vidtmkvmk »

filleokus wrote: post #84

> Not Good For: > User IDs - Can be decoded, revealing user count Suppose you don't want to leak the count, what's a resonable way of implementing that? You can of course have a uuid v7 / uulids or something as the primary key. Or have it as a public facing primary key, mapping back to a sequential ID PK (there might be some performance hits with larger PK's in e.g postgres? or is that just fud?) But you could also g…

Add an offset, multiply by a large prime number, and modulo. I don't think you can recover the original number without figuring out the prime.

Re: Sqids – Generate short unique IDs from numbers

#96

Post by orf »

How do you adjust or evolve the blocklist with this, without making previously generated IDs incorrect?

The ID is simply incremented if it is blacklisted [1]. So the ID is fixed to the blacklist content, and adjusting it in any way invalidates certain segments of previously generated IDs?

1. https://github.com/sqids/sqids-rust/blob/9f987886bc06875d782...

Re: Sqids – Generate short unique IDs from numbers

#98

Post by pelagicAustral »

vyrotek wrote: post #42
progne wrote: post #38

In a Ruby app we just convert to a high base, like > 1234567890.to_s(36) => "kf12oi" That gets us most of the way there, but Sqid has a Ruby library and lets you set a much higher base, including upper case characters, and I suppose, emoji. We're going to need much bigger numbers before that space savings makes much difference. I like it, but it's hard to know when something like that is worth adding a dependency.

I believe a big part of the idea is for the hash to be unpredictable as well. If I figure out you're using (36) then I know the next number 1234567891 is "kf12oj". Not the case with Sqids.

Correct me if I'm wrong, but, It cannot be unpredictable, which makes the library redundant for security concerns, which would be the one business case to seek for anything other than an UUID (which is already built into Ruby).

Re: Sqids – Generate short unique IDs from numbers

#99

Post by paulddraper »

parhamn wrote: post #70

Side note: there are some business insights you can get from a company using serial ids. i.e if you sign up and get user id 32588 and make another account a few days later, you can tell the growth rate of the company. And this is possible with every resource type in the application. I do wonder how much the url bar junk thing matters these days. I tend to use uulids (waiting on uuid v7 wide adoption), and they're a b…

> most browsers

Not chrome...

Also, links are a thing in chat, etc

Re: Sqids – Generate short unique IDs from numbers

#100

Post by paulddraper »

vyrotek wrote: post #42
progne wrote: post #38

In a Ruby app we just convert to a high base, like > 1234567890.to_s(36) => "kf12oi" That gets us most of the way there, but Sqid has a Ruby library and lets you set a much higher base, including upper case characters, and I suppose, emoji. We're going to need much bigger numbers before that space savings makes much difference. I like it, but it's hard to know when something like that is worth adding a dependency.

I believe a big part of the idea is for the hash to be unpredictable as well. If I figure out you're using (36) then I know the next number 1234567891 is "kf12oj". Not the case with Sqids.

No, squids are predictable, you can't use them to hide information.

They call it out on their front page.

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