ImmutableJS: how to convert to JSON an opaque variable - immutable.js

I have an opaque variable on my hand. I know it can be an object, a primitive value, an immutable, or an object whose values can be immutables.
I need to convert deeply this object to json for logging.
The following does not work, because it does not cover the case where the immutables are nested inside a real json object:
const json = isImmutable(obj)
? obj.toJS()
: obj
Is there a simple way to convert my opaque structure to json?
I know nesting immutables in non immutables may not be such a good idea. Still looking for a simple solution that does not involve large refactorings.

Try this
console.log(Immutable.fromJS(obj).toJS());
Here, first step is to convert the entire "obj" to immutable using fromJS(). Doing so will make all the nested plain objects and arrays immutable. Final step is to convert the entire "obj' to plainJS by using toJS(). End result is plainJS "obj"

Related

How can I use serde_json to deserialize arbitrary JSON into a Value-like object of raw bytes?

I'm writing a library to deserialize a subset of JSON into predefined Python types.
I want to deserialize arbitrary JSON into an object that quacks like serde-json's Value. However, I don't want it to deserialize into String's, Number's and Bool's - instead when the deserializer hits one of these I would prefer it simply keeps a reference to the respective byte string so I can efficiently (i.e. without the additional type conversion) parse the byte strings into the correct arbitrary Python types. Something like this:
use serde::Deserialize;
use serde_json::value::RawValue;
use serde_json::Map;
#[derive(Deserialize)]
pub enum MyValue<'a> {
Null,
Bytes(&'a RawValue),
Array(Vec<MyValue<'a>>),
Object(Map<String, MyValue<'a>>),
}
This will require writing a lot of traits so that it behaves like Value, and I'm not even sure if it won't just ignore deserializing the structural parts and put everything into a RawValue.
What is the cleanest way to do this?

Prevent parsing a JSON node with common-lisp YASON library

I am using the Yason library in common-lisp, I want to parse a json string but would like the parser to keep one a its node unparsed.
Typically with an example like that:
{
"metadata1" : "mydata1",
"metadata2" : "mydata2",
"payload" : {...my long payload object},
"otherNodesToParse" : {...}
}
How can I set the yason parser to parse my json but skip the payload node and keep it as a string in the json format.
Use: let's say I just want the envelope data (everything that's not the payload), and to forward the payload as-is (as json string) to another system.
If I parse the whole json (so including payload) and then re-encode the payload to json, it is inefficient. The payload size could also be pretty big.
How do you know where the end of the payload object is in the stream? You do so by parsing the stream: if you don't parse the stream you simply can't know where the end of the object is: that's the nature of JSON's syntax (as it is the nature of CL's default syntax). For instance the only way you can know the difference between where to continue after
{x:1}
and after
{x:1.2}
is by parsing the two things.
So you must necessarily parse the whole thing.
So the answer to your question is: you can't do this.
You could (but not, I think, with YASON) decide that you did not want to build an object as a result of the parse. And perhaps, if the stream you are parsing corresponds to something with random access like a string or a file, you could note the start and end positions in the stream to later extract a string from it corresponding to the unparsed data (or you could perhaps build it up as you go).
It looks as if some or all of this might be possible with CL-JSON, but you'd have to work at it.
Unless the objects you are reading are vast the benefit of this seems questionable-to-none. If you really do want to do something like this efficiently you need a serialisation scheme which tells you how long things are.

Add/Remove elements in a JSON Array in Scala/Play

I have a pretty complex JSON object that contains, among other things, some JSON arrays that I need to update, removing and adding elements.
To do that I'm trying to use a JsPath that point directly to the object inside the array that I need to remove, something like:
/priceLists(1)/sections(0)/items(0)
to remove the element I tried to use json.prune and it doesn't work, I get this error: error.expected.jsobject
Would would be the best way to do that?
Your question is lacking a precise context (i.e., structure of your json data), but let's do with what we have.
The error message you get is clear, you can only call prune on a json object, to prune one of its values. You can't use it to prune an element of a json array.
I can only advise you to use json.update, stating that like prune, update only works on json objects. In the body of the update, work on your arrays as you usually do with scala/java data types.
__.json.update(__.reads[JsArray].map { jsArray =>
val removedElement = JsArray(jsArray.value.filter(_ == ???))
val addedElement = removedElement :+ JsBoolean(true)
addedElement
})

name json variable and jsonString variable convention?

JSON could mean JSON type or json string.
It starts confuse me when different library use json in two different meanings.
I wonder how other people name those variables differently.
For all practical purposes, "JSON" has exactly one meaning, which is a string representing a JavaScript object following certain specific syntax.
JSON is parsed into a JavaScript object using JSON.parse, and an JavaScript object is converted into a JSON string using JSON.stringify.
The problem is that all too many people have gotten into the bad habit of referring to plain old JavaScript objects as JSON. That is either confused or sloppy or both. {a: 1} is a JS object. '{"a": 1}' is a JSON string.
In the same vein, many people use variable names like json to refer to JavaScript objects derived from JSON. For example:
$.getJSON('foo.php') . then(function(json) { ...
In the above case, the variable name json is ill-advised. The actual payload returned from the server is a JSON string, but internally $.getJSON has already transformed that into a plain old JavaScript object, which is what is being passed to the then handler. Therefore, it would be preferable to use the variable name data, for example.
If a library uses the term "json" to refer to things which are not JSON, but actually are JavaScript objects, it is a mark of poor design, and I'd suggest looking around for a different library.

Use JSON.stringify but the data still have array, what does it mean?

I have a data which are object array. It contains object arrays in a tree structure. I use JSON.stringify(myArray) but the data still contain array because I see [] inside the converted data.
In my case, I want all the data to be converted into json object not array regarding I need to used the data on TreeTable of SAPUI5.
Maybe I misunderstand. Please help me clear.
This is the example of the data that I got from JSON.stringify.
[{"value":{"Id":"00145E5BB2641EE284F811A7907717A3",
"Text":"BI-RA Reporting, analysis, and dashboards",
"Parent":"00145E5BB2641EE284F811A79076F7A3","Type":"BMF"},
"children":[{"value":{"Id":"00145E5BB2641EE284F811A7907737A3",
"Text":"WebIntelligence_4.1","Parent":"00145E5BB2641EE284F811A7907717A3",
"Type":"TWB"},"children":[{"value":{"Id":"00145E5BB2641EE284F811A7907757A3",
"Text":"Functional Areas","Parent":"00145E5BB2641EE284F811A7907737A3","Type":"TWB"},
"children":[{"value":{"Id":"00145E5BB2641EE284F811A7907777A3",
"Text":"CHARTING","Parent":"00145E5BB2641EE284F811A7907757A3","Type":"TWB"},
"children":[{"value":{"Id":"001999E0B9081EE28AB706BE26631E93",
"Text":"Drill","Parent":"00145E5BB2641EE284F811A7907777A3","Type":"TWB"},
"children":[{"value":{"Id":"001999E0B9081EE28AB706BE26633E93",
"Text":"[AUTO][ACCEPT] Drill on charts DHTML","Parent":"001999E0B9081EE28AB706BE26631E93",
"Type":"TWB","Ref":"UT_WEBI_CHARTS_DRILL_HTML"}},{"value":{"Id":"001999E0B9081EE28AB706BE26635E93",
"Text":"[AUTO][ACCEPT] Drill on charts JAVA","Parent":"001999E0B9081EE28AB706BE26631E93",
"Type":"TWB","Ref":"UT_WEBI_CHARTS_DRILL_JAVA"}}]},...
The output that I want shouldn't be array of object but should be something like...
{{"value":{
"Id":"00145E5BB2641EE284F811A7907717A3",
"Text":"BI-RA Reporting, analysis, and dashboards",
"Parent":"00145E5BB2641EE284F811A79076F7A3","Type":"BMF"},
"children":{
{"value":{
"Id":"00145E5BB2641EE284F811A7907737A3",
"Text":"WebIntelligence_4.1",
"Parent":"00145E5BB2641EE284F811A7907717A3",
"Type":"TWB"},
"children":{
{"value":{
"Id":"00145E5BB2641EE284F811A7907757A3",
"Text":"Functional Areas",
"Parent":"00145E5BB2641EE284F811A7907737A3",
"Type":"TWB"},...
JSON.stringify merely converts JavaScript data structures to a JSON-formatted string for consumption by other parsers (including JSON.parse). If you want it to stringify to a different value, you must change the source data structures first.
However, it seems that this can't be represented as anything other than an array because you have duplicate keys (i.e. value appears more than once). That would not be valid for a JavaScript object or a JSON representation of such.
I think what you want is
JSON.stringify(data[0]);
or perhaps
JSON.stringify(data[0].value);
where data is the object you passed in the question