ideas for 2 new json builtins

Question

While answering https://forum.plantuml.net/15326/add-edges-in-diagram-without-touching-existing-json-data, I thought about two new preprocessor built-in functions that would have been useful to make the idea more readable:

1) %get_json_type($json) returns int

• (0 - Not valid Json, optional)
• 1 - JSON array ($json starts '[')
• 2 - JSON object ($json starts '{')
• 3 - JSON other = string / number / boolean / null  (or give each its own return code)

2) %get_json_keys($json_object) returns new json array containing the keys from the parameter object.  For example '{"name": "Mark McGwire", "hr":   65, "avg":  0.278}' would return '["name","hr","avg"]'.  

These two combined would let you write:

!if %get_json_type($myjson) == JSON_OBJECT
   !foreach $key in %get_json_keys($myjson)
      !if %get_json_type($myjson[$key]) == JSON_STRING
         rectangle $myjson[$key]
      !endif
   !endfor
!endif

Just an idea.

Answer 1

This is a brillant idea, we like it! Many thanks for the suggestion.

So with last snapshot (and on the online server), you can now have this:

• Example1
• Example2
• Example3

This has not been really tested, so feedback is welcome :-)

Comments

Thank you.  Looks good!

I like the return values of strings rather than numbers, good idea.  Although maybe null should map to "null" rather than to "json"?

I notice that %get_json_keys not only works on a json object, but also works on a json array where all the elements are objects, I'm not sure how useful this is but it is neat!

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Cool, but How it's possible to check if a key exist ?

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Hello P., and all,

See similar request here:

• https://forum.plantuml.net/15423/functions-check-exists-default-value-get_variable_value

With an attempts to `json_key_exists` on pure plantUML...

Regards.