4 ms·

JavaScript Object Notation (JSON) Pointer (2013)

17 points by stefankuehnel 4y ago

stefankuehnel 4y ago
Abstract JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document.
jupp0r 4y ago
"Note that JSON pointers can contain the NUL (Unicode U+0000) character. Care is needed not to misinterpret this character in programming languages that use NUL to mark the end of a string." What could possibly go wrong?
- zerocrates 4y ago
  I wonder why it allows NUL... I'm pretty sure JSON itself doesn't: you need to do a \u escape to do the control characters including NUL. It looks like that kind of escaping is just not supported at all in JSON Pointer. I kind of want to say that once you've noticed NUL is a problem enough to call it out the document, you should probably just ban it and pop in an escape to represent it.
2h 4y ago
2013
- hyperhello 4y ago
  I’m guessing no one wanted this, because stepping into JSON with forward slashes is trivial if you wanted to do it, and no one would do that. Making a standardized “safe” JSON query like json.array[3][“baz”] that is JS compatible might be interesting, but still really trivial to do.
thadk 4y ago
If you don't need multi-language support, it seems like there may be more natural ways to point at a particular part of a JSON object. This issue has a few different implementations and alternatives: https://github.com/akheron/optics-ts/issues/241 https://github.com/akheron/optics-ts/issues/241
nighthawk454 4y ago
I was wondering how this differs from JSONPath, found some answers on google: > jsonpointer just defines how to access to a single value inside a json document, whereas jsonpath has more powerful features like union (extract multiple values), filters and deep search (recursively match a path). > But jsonpath is missing a proper specification, so some behaviors are implementation specific with some parts heavily depending on some javascript constructs (mainly filters). https://github.com/yalp/jsonpath/issues/1#issuecomment-137081081 https://github.com/yalp/jsonpath/issues/1#issuecomment-13708...
- beached_whale 4y ago
  A simple subset of JSONPath is nice, it looks just like code. e.g foo.bar[5].value and encodes that we expect a member name or a indice into the array or class. It’s common to have numeric string member names in JSON when dealing with associative structures of KV pairs.
- fanf2 4y ago
  There is an IETF working group developing a spec for jsonpath https://datatracker.ietf.org/wg/jsonpath/documents/ https://datatracker.ietf.org/wg/jsonpath/documents/
oweiler 4y ago
JSON Pointer is just not powerful enough except for the simplest use cases. I very much prefer JSON Path.
deleted 4y ago
[deleted]
avmich 4y ago
Looks like in this proposal a less common escape technique is used. I wonder if we can adopt a standardized escaping method across various standards, languages and data structures, so one doesn't need to learn specifics every time.

17 points by stefankuehnel 4y ago

Abstract JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document.

jupp0r 4y ago

"Note that JSON pointers can contain the NUL (Unicode U+0000) character. Care is needed not to misinterpret this character in programming languages that use NUL to mark the end of a string." What could possibly go wrong?

zerocrates 4y ago
I wonder why it allows NUL... I'm pretty sure JSON itself doesn't: you need to do a \u escape to do the control characters including NUL. It looks like that kind of escaping is just not supported at all in JSON Pointer. I kind of want to say that once you've noticed NUL is a problem enough to call it out the document, you should probably just ban it and pop in an escape to represent it.

2h 4y ago

2013

hyperhello 4y ago
I’m guessing no one wanted this, because stepping into JSON with forward slashes is trivial if you wanted to do it, and no one would do that. Making a standardized “safe” JSON query like json.array[3][“baz”] that is JS compatible might be interesting, but still really trivial to do.

thadk 4y ago

If you don't need multi-language support, it seems like there may be more natural ways to point at a particular part of a JSON object. This issue has a few different implementations and alternatives: https://github.com/akheron/optics-ts/issues/241 https://github.com/akheron/optics-ts/issues/241

nighthawk454 4y ago

I was wondering how this differs from JSONPath, found some answers on google: > jsonpointer just defines how to access to a single value inside a json document, whereas jsonpath has more powerful features like union (extract multiple values), filters and deep search (recursively match a path). > But jsonpath is missing a proper specification, so some behaviors are implementation specific with some parts heavily depending on some javascript constructs (mainly filters). https://github.com/yalp/jsonpath/issues/1#issuecomment-137081081 https://github.com/yalp/jsonpath/issues/1#issuecomment-13708...

beached_whale 4y ago
A simple subset of JSONPath is nice, it looks just like code. e.g foo.bar[5].value and encodes that we expect a member name or a indice into the array or class. It’s common to have numeric string member names in JSON when dealing with associative structures of KV pairs.
fanf2 4y ago
There is an IETF working group developing a spec for jsonpath https://datatracker.ietf.org/wg/jsonpath/documents/ https://datatracker.ietf.org/wg/jsonpath/documents/

oweiler 4y ago

JSON Pointer is just not powerful enough except for the simplest use cases. I very much prefer JSON Path.

deleted 4y ago

[deleted]

avmich 4y ago

Looks like in this proposal a less common escape technique is used. I wonder if we can adopt a standardized escaping method across various standards, languages and data structures, so one doesn't need to learn specifics every time.