For a sample JSON data which looks like this -
{
"children":{
"Alice":{...},
"Jamie":{...},
"Bob":{...}
// Any new child with a given unique name will be added to this object
},
childrenOrder:["Alice", "Bob", "Jamie"]
}
In the corresponding JSON Schema, I am trying to limit the valid values in "childrenOrder" array to be from the run time children keys.
I didn't see any means of referring to runtime dynamic values in the official JSON Schema documentation (http://json-schema.org/documentation.html).
Is this even possible at the moment?
For the sake of brevity I omitted JSON Schema code. I can add it if folks think it is needed to address the question.
Thanks in advance.
No it is not possible using the current JSON Schema specification. However, there is a proposal for the next version of JSON Schema that could change that.
https://github.com/json-schema/json-schema/wiki/%24data-(v5-proposal)
Related
I have created a number of JSON schemas that reference http://json-schema.org/draft-04/schema#. Let's say I call these myschema1.schema.json, myschema2.schema.json etc. I am saving JSON strings that have been validated against one of these schemas and at a later date I need to be able to edit that data and re-validate it against the original schema. How can I include a reference to the original schema in the saved JSON file? I thought about simply including it as a property but I don't want this schema property to be included when dynamically creating a class based on the JSON properties as I don't want it to be included in the edit form.
Here's what I would like to be able to do..
{
"$schema": "http://someURI/myschema1",
"Property 1": "One",
"Property 2": "Two"
}
..but as the property name $schema is not included in the schema it fails validation. Any suggestions would be most welcome. Thanks!
The json data structure for jstree is define in https://github.com/vakata/jstree, here is an example
[ { "text" : "Root node", "children" : [ "Child node 1", "Child node 2" ] } ]
Notably it says
The children key can be used to add children to the branch, it should
be an array
However later on in section Populating the tree using AJAX and lazy loading nodes it shows to use set children to false to indicate when a child has not be processed
[{
"id":1,"text":"Root node","children":[
{"id":2,"text":"Child node 1","children":true},
{"id":3,"text":"Child node 2"}
]
}]
So here we see children used as both as an array and as a boolean
I am using jstree as an example because this is where I encountered the issue, but my question is really a general json question. My question is this, is it valid JSON for the same element in json to be two different types (an array and a boolean)
Structure wise, both are valid JSON packets. This is okay, as JSON is somewhat less stricter than XML(with a XSD or a DTD). As per: https://www.w3schools.com/js/js_json_objects.asp,
JSON objects are surrounded by curly braces {}.
JSON objects are written in key/value pairs.
Keys must be strings, and values must be a valid JSON data type (string, number, object, array, boolean or null).
Keys and values are separated by a colon.
Each key/value pair is separated by a comma.
Having said that, if the sender is allowed to send such JSONs, only caveat is that server side will have to handle this discrepancy upon receiving such different packets. This is a bad-looking-contract, and hence server might need to do extra work to manage it. Server side handling of such incoming JSON packets can become tricky.
See: How do I create JSON data structure when element can be different types in for use by
You could validate whether a JSON is okay or not at https://jsonlint.com/
See more about JSON in this answer: https://stackoverflow.com/a/4862511/945214
It is valid Json. JSON RFC 8259 defines a general syntax but it contains nothing that would allow a tool to identify that two equally named entries are meant to describe the same conceptual thing.
The need to have a criteria to check two JSON structures for instance equality has been one motivation to create something like Json Schema.
I also think it is not too unusual for javascript to provide this kind of mixed data. Sometimes it might help to explicitly convert the javascript object to JSON. Like in JSON.stringify(testObject)
A thing for json validation
https://www.npmjs.com/package/json-validation
https://davidwalsh.name/json-validation.
I got an anonymous array which I want to deserialize, here the example of the first array object
[
{ "time":"08:55:54",
"date":"2016-05-27",
"timestamp":1464332154807,
"level":3,
"message":"registerResourcePath ('', '/sap/bc/ui5_ui5/ui2/ushell/resources/')",
"details":"","component":"sap.ui.ModuleSystem"},
{"time":"08:55:54","date":"2016-05-27","timestamp":1464332154808,"level":3,"message":"URL prefixes set to:","details":"","component":"sap.ui.ModuleSystem"},
{"time":"08:55:54","date":"2016-05-27","timestamp":1464332154808,"level":3,"message":" (default) : /sap/bc/ui5_ui5/ui2/ushell/resources/","details":"","component":"sap.ui.ModuleSystem"}
]
I tried deserializing using CL_TREX_JSON_SERIALIZER, but it is corrupt and does not work with my JSON, here is why
Then I tried /UI2/CL_JSON, but it needs a "structure" that perfectly fits the object given by the JSON Object. "Structure" means in my case an internal table of objects with the attributes time, date, timestamp, level, messageanddetails. And there was the problem: it does not properly handle references and uses class description to describe the field assigned to the field-symbol. Since I can not have a list of objects but only a list of references to objects that solution also doesn't works.
As a third attempt I tried with the CALL TRANSFORMATION as described by Horst Keller, but with this method I was not able to read in an anonymous array, and here is why
My major points:
I do not want to change the JSON, since that is what I get from sap.ui.log
I prefere to use built-in functionality and not a thirdparty framework
Your problem comes out not from the anonymity of array, but from the awkwardness of SAP JSON (De)serializer, which doesn't respect double quotes, which enclose JSON attributes. The issue is thoroughly described in this answer.
If you don't want to change your JSON on-the-fly, the only way you have is to change CL_TREX_JSON_DESERIALIZER class like this.
/UI5/CL_JSON_PARSER parses JSONs with unknown format.
Note that it's got "for internal use" written on it so many times that you probably should take it seriously and clone its code to fixate it.
I am asking this because I see that the current JSON schema draft (http://json-schema.org/) proposes to have the schema of JSON in the following way:
for the JSON :
{
"a":"abc"
"b": 123
}
the schema proposed in the draft is like
{
"type":"object"
"properties":{
"a": {"type":"string"}
"b": {"type":"integer"}
}
}
My question here is does the JSON itself not define its structure? Is a separate schema necessary?
The schema proposed by the draft validates the JSON that have the above structure and those JSON are always of the format
{
"a":"string"
"b": 1 (or some number)
}
So what is the need of a separate schema for JSON. We can simply use the JSON to define its structure also.
PS. I know that we can specify some restrictions on the values that the JSON can take through the schemas proposed in the draft, but from the point of view of defining structure of a JSON, are the proposed schemas necessary?
The JSON itself does not define the structure. For example, I could write:
{
"a": "string",
"b": "another string"
}
That's also valid JSON - but it's "differently structured" JSON, because "b" is now a string. But your API might only accept JSON with a particular structure, so although it's valid JSON, it's not the shape you need.
Now, do you need JSON Schema to define the structure of your JSON data? No. You could instead say:
The value must be an object. It must have two properties:
"a" - must be a string
"b" - must be an integer
A programmer could understand this very easily, with no squiggly brackets or anything.
However, there are advantages to having a machine-readable description of the format, because it lets you automate various things (e.g. testing, generating documentation, generating code/classes, etc.)
Edit: As pointed out in the comments, you can take the type information from some example data, and use that as a model for other data. In this case, you're basically using your example data as a super-basic schema.
For very simple constraints (basic type), this works. However, how would you say that "b" has to be an integer instead of a float? How do you say that "b" must be > 0? How do you say that "a" must not be the empty string ("")?
There are indeed tools that generate a basic JSON Schema from example data - however, the resulting schema usually requires a bit of tweaking to actually describe the format (e.g. min/max, required/optional properties, etc.).
Until now have never been necessary and in the short term I don't think it gets to be.
I personally like JSON because its simplicity, portability and flexibility.
I don't see even major brands using that schema so until now they don't take its serious.
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