PMLJsonNet

PMLJsonNet provides an interface for processing JSON in AVEVA PML2.

Installation

1. Download the ZIP archive from Releases.

2. Extract the files and folders from the ZIP archive and place them in a directory specified by the PMLLIB environment variable.

3. Launch an AVEVA product.

4. Enter the following command in the Command Window:

   pml rehash all
   

Usage

.Parse(!json is STRING, !object is ANY)

The Parse method parses a JSON string and stores the result in the specified object.

• Example:

  using namespace 'PMLJsonNet'
  !json = object PMLJSON()
  !obj = object POSITION()
  !json.Parse('{"east":123,"north":456,"up":789,"origin":"/*"}', !obj)
  q var !obj
  

• Output in the Command Window:

  <POSITION> E 123mm N 456mm U 789mm WRT /*
     EAST <REAL> 123
     NORTH <REAL> 456
     ORIGIN <DBREF> =****/0 (Refno depends on DB No.)
     UP <REAL> 789
  

.Parse(!file is FILE, !object is ANY)

The Parse method parses a JSON file and stores the result in the specified object.

• Example:

  using namespace 'PMLJsonNet'
  !json = object PMLJSON()
  !file = object FILE('%temp%\sample.json')
  !obj = object DICTIONARY()
  !json.Parse(!file, !obj)
  q var !obj.keys !obj.values
  q var !obj.values[1].keys !obj.values[1].values
  q var !obj.values[2]
  

• Contents of sample.json:

  {
    "dictionary": { "foo": 123, "bar": 456, "baz": 789 },
    "array": ["foo", 123, true],
    "boolean": false,
    "real": 1.23e4,
    "string": "foo\\bar \"baz\"",
    "null": null
  }
  

• Output in the Command Window:

  <ARRAY>
     [1]  <STRING> 'dictionary'
     [2]  <STRING> 'array'
     [3]  <STRING> 'boolean'
     [4]  <STRING> 'real'
     [5]  <STRING> 'string'
     [6]  <STRING> 'null'
  <ARRAY>
     [1]  <DICTIONARY> DICTIONARY
     [2]  <ARRAY> 3 Elements
     [3]  <BOOLEAN> FALSE
     [4]  <REAL> 12300
     [5]  <STRING> 'foo\bar "baz"'
     [6]  <STRING> Unset
  
  <ARRAY>
     [1]  <STRING> 'foo'
     [2]  <STRING> 'bar'
     [3]  <STRING> 'baz'
  <ARRAY>
     [1]  <REAL> 123
     [2]  <REAL> 456
     [3]  <REAL> 789
  
  <ARRAY>
     [1]  <STRING> 'foo'
     [2]  <REAL> 123
     [3]  <BOOLEAN> TRUE
  

.Stringify(!object is ANY) is STRING

The Stringify method returns a JSON string generated from the specified object's data.

• Example:

  using namespace 'PMLJsonNet'
  !json = object PMLJSON()
  !result = !json.Stringify( N WRT /* )
  $P$!result
  

• Output in the Command Window:

  {"EAST":0,"NORTH":1,"ORIGIN":"/*","UP":0}
  

.WriteFile(!file is FILE, !object is ANY)

The WriteFile method writes the specified object's data to a JSON file.

• Example:

  using namespace 'PMLJsonNet'
  !json = object PMLJSON()
  !file = object FILE('%temp%\sample.json')
  !obj = object POINTVECTOR( E 123 N 456 U 789 WRT /* , U WRT /* )
  !json.WriteFile(!file, !obj)
  

• Output in sample.json:

  {
    "DIRECTION": {
      "EAST": 0,
      "NORTH": 0,
      "ORIGIN": "/*",
      "UP": 1
    },
    "POSITION": {
      "EAST": "123mm",
      "NORTH": "456mm",
      "ORIGIN": "/*",
      "UP": "789mm"
    }
  }
  

.WriteFile(!file is FILE, !object is ANY, !indent is REAL)

The WriteFile method writes the specified object's data to a JSON file using the specified indentation width.

• Example:

  using namespace 'PMLJsonNet'
  !json = object PMLJSON()
  !file = object FILE('%temp%\sample.json')
  !obj = object DICTIONARY()
  !obj.SetValue('Array', Split('foo bar baz'))
  !obj.SetValue('Real', 12.3kg)
  !obj.SetValue('String', 'foo\bar "baz"')
  !obj.SetValue('DBRef', Nulref, true)
  !json.WriteFile(!file, !obj, 0)
  

• Output in sample.json:

  {"Array":["foo","bar","baz"],"Real":"12.3kg","String":"foo\\bar \"baz\"","DBRef":null}
  

Tests

The test cases use PML Unit and were run on Everything3D 2.1.

License

MIT License