feat: add feel property

[marstamm]

related to bpmn-io/bpmn-js-properties-panel#606

[marstamm]

@pinussilvestrus, I tried out to implement the rule "Feel is only valid for type String and Text" and actually got it to work 😄
Could you give it a quick check whether using if/then together with not is the correct approach here? Maybe there is a more elegant approach that I am not aware of yet

relevant lines: https://github.com/camunda/element-templates-json-schema/pull/46/files#diff-94dce962273655c5b1774e11a13b912d8316a6ef64bfb0ea0610a645de92ea18R30-R53

[pinussilvestrus]

Looks good basically. If you want to, I could do another try on Monday whether we can make the rule a bit more readable. 👍

[marstamm]

Thank you for the feedback! I will look into this on monday and come back to you if it does not work

[pinussilvestrus]

Maybe something like this (using a similar pattern as for optional)

{
  "if": {
    "properties": {
      "feel": {
        "not": {
          "const": null
        }
      }
    },
    "required": [
      "feel"
    ]
  },
  "then": {
    "properties": {
      "type": {
        "enum": [
          "String",
          "Text"
        ],
        "errorMessage": "feel is only valid for \"String\" and \"Text\" type"
      }
    },
    "required": [
      "type"
    ]
  }
}

[marstamm]

Thank you for the feedback! I changed the PR accordingly. Ready for review again

[pinussilvestrus]

Nice!

[pinussilvestrus]

@marstamm fyi: I squashed the two commits together on master, to ensure we don't have changes on sub packages that shouldn't have some. Only zeebe-element-templates-json-schema should be affected. This way it should make it easier for lerna to only release changed packages on npm run release 👍 .

[marstamm]

Thank you for the heads up. #45 changed the examples and titles of everything, so we will release patches for shared and camunda schema anyway 😄