fix(CanvasForm): Expression field shows `[object Object]`

[lordrip]

Context

When a new expression-aware step is generated, the expression property is created as follows:

        setHeader:
          id: setHeader-1234
          expression:
            simple:
              expression: {}

Notice the expression: {} bit which causes for the expression TextField to render [object Object]

Changes

Replace the autogenerated step with an empty simple: {}, so there's the feedback that a property is left to be configured. In the future, there will be the same feedback in the Canvas as well. https://github.com/KaotoIO/kaoto/issues/705

        setHeader:
          id: setHeader-1234
          expression:
            simple: {}

Note

This comes from this PR https://github.com/KaotoIO/kaoto/pull/1068, in which I suggested using expression: {} for the newly created step.

fix: https://github.com/KaotoIO/kaoto/issues/1076

[apupier]

if I understand well, for the setBody, when inserting the element, it is setting the body to empty string ad there won't be any message to tell user to configure the field. It sounds better to not have any values in this case. Because I fear that a lot of users will forget to modify it and will not understand why the body is "lost".

[lordrip]

if I understand well, for the setBody, when inserting the element, it is setting the body to empty string ad there won't be any message to tell user to configure the field. It sounds better to not have any values in this case. Because I fear that a lot of users will forget to modify it and will not understand why the body is "lost".

Updated

[lhein]

Although we did not yet implement any check if the expression is filled, the behavior now is that just simple is selected and the expression is empty. This will make it easier to spot the missing bit once we have the validation ready.

[apupier]

current behavior is that:

• when opening textual file, there is a validation error spotted
• when running, for instance with setBody, the body is set null at runtime.

Slightly better than empty string but still not ideal.