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The Pretty JSON Revolution

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Re: The Pretty JSON Revolution

#11

Post by peterohler »

taeric wrote: post #5
Macha wrote: post #3

If you're on a mac or Linux system, you likely have a JSON formatter already installed `python3 -m json.tool somefile.json` or `cat foo.json | python3 -m json.tool` will print it in "one line per node" format. 3.9 introduces a --sort-keys switch for sorted objects also.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

It is a stable sort since for almost every parser out there there can be no duplicate keys. It would be dangerous for an JSON parser to assume JSON object keys are in some specific order. It is certainly not something that can be counted on in golang, Ruby, or Python.

Re: The Pretty JSON Revolution

#12

Post by igetspam »

taeric wrote: post #5
Macha wrote: post #3

If you're on a mac or Linux system, you likely have a JSON formatter already installed `python3 -m json.tool somefile.json` or `cat foo.json | python3 -m json.tool` will print it in "one line per node" format. 3.9 introduces a --sort-keys switch for sorted objects also.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

If you have a parser that's looking at keys in a hash as sorted, you should change your parser. Lists sure but not keys.

Re: The Pretty JSON Revolution

#13

Post by Macha »

taeric wrote: post #5
Macha wrote: post #3

If you're on a mac or Linux system, you likely have a JSON formatter already installed `python3 -m json.tool somefile.json` or `cat foo.json | python3 -m json.tool` will print it in "one line per node" format. 3.9 introduces a --sort-keys switch for sorted objects also.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

Pretty printing JSON is mostly for developer consumption, I'm not sure how the pretty printed JSON would end up being fed automatically to another system?

(I have actually encountered a order-dependent JSON-subset parser before, but to my mind, that code is broken)

Re: The Pretty JSON Revolution

#14

Post by Splognosticus »

peterohler wrote: post #11
taeric wrote: post #5

Earlier quoted context omitted.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

It is a stable sort since for almost every parser out there there can be no duplicate keys. It would be dangerous for an JSON parser to assume JSON object keys are in some specific order. It is certainly not something that can be counted on in golang, Ruby, or Python.

Also in violation of the spec:

> An object is an unordered collection of zero or more name/value pairs, where a name is a string and a value is a string, number, boolean, null, object, or array.

https://tools.ietf.org/html/rfc7159#section-1

Re: The Pretty JSON Revolution

#15

Post by foobarian »

Macha wrote: post #3

If you're on a mac or Linux system, you likely have a JSON formatter already installed `python3 -m json.tool somefile.json` or `cat foo.json | python3 -m json.tool` will print it in "one line per node" format. 3.9 introduces a --sort-keys switch for sorted objects also.

jq is a very nice tool for JSON wrangling available to install on most distros. It also provides key sorting, which is great for diff-ing JSON.

Re: The Pretty JSON Revolution

#17

Post by quietbritishjim »

peterohler wrote: post #11
taeric wrote: post #5

Earlier quoted context omitted.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

It is a stable sort since for almost every parser out there there can be no duplicate keys. It would be dangerous for an JSON parser to assume JSON object keys are in some specific order. It is certainly not something that can be counted on in golang, Ruby, or Python.

> It is certainly not something that can be counted on in golang, Ruby, or Python.

As of Python 3.6 (in theory not guaranteed until Python 3.7), key order is preserved when reading and writing. That's a consequence of the fact Python dictionaries can now remember the order of insertion.

It's true that it doesn't support duplicate keys though (unless you pass in a different class to the object_pairs_hook parameter of loads() to replace its use of dict).

Re: The Pretty JSON Revolution

#18

Post by peterohler »

taeric wrote: post #10

I would prefer one that aligned the like named keys, if it fits in screen. Makes it dead easy to scan the values. That said, it is just another pun on the text as art thing. In that it doesn't really scale, and you are going to upset someone by not having a codified tool for automatically doing this. (I don't recall seeing align-regex in any popular tool.)

Can you explain what you mean by "like named"? The sorting helps a lot but I'm always interested in additional features.

Re: The Pretty JSON Revolution

#19

Post by peterohler »

vicpara wrote: post #16

JSON is mostly for machines not people. When needed, developers format their json in their code editor of choice or bash.

There are a lot of people who store JSON in NoSQL databases. After fetching a JSON records you generally view the JSON or you do as a developer. That is where the tool is handy as you get get something like a FHIR record on a single page instead of crunched into a single line to expanded over multiple pages.

Re: The Pretty JSON Revolution

#20

Post by lucideer »

taeric wrote: post #5
Macha wrote: post #3

If you're on a mac or Linux system, you likely have a JSON formatter already installed `python3 -m json.tool somefile.json` or `cat foo.json | python3 -m json.tool` will print it in "one line per node" format. 3.9 introduces a --sort-keys switch for sorted objects also.

I would be a little nervous sorting the keys. I thought it was not too uncommon for parsers to treat them as an alist where order matters. I guess so long as it is a stable sort, no big deal?

If you have an application that's dependent on JSON key order, then you're not passing it prettified JSON.

The main apps I've seen that depend on JSON structure are for hashing, which would also be broken by whitespace / linebreak variances in pretty-printers.

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