Flow wont import into PA with a dual data type

[martinav]

I have a response action sending data back to PA.  Its been hours of messing with other problems, but now PA wont let me import the flow if the schema has a variable with dual data type with null.  WTH is the deal?

I get this lame error:

I take that variable out, and its all good.  What the He11?

The variable _SNValve is the one that makes the flow import fail.

{
    "type": "array",
    "items": {
        "type": "object",
        "properties": {
            "Description": {
                "type": "string"
            },
            "ProductID": {
                "type": "string"
            },
            "LineNumber": {
                "type": "integer"
            },
            "QtyOrdered": {
                "type": "integer"
            },
            "QtyInvoiced": {
                "type": "integer"
            },
            "QtyScheduled": {
                "type": "integer"
            },
            "QtyPicked": {
                "type": "integer"
            },
            "QtyBackordered": {
                "type": "integer"
            },
            "QtyOutstanding": {
                "type": "integer"
            },
            "OrderNumber2": {
                "type": "string"
            },
            "_SNValve": {
                "type": [
                    "string",
                    "null"
                ]
            }
        },
        "required": [
            "Description",
            "ProductID",
            "LineNumber",
            "QtyOrdered",
            "QtyInvoiced",
            "QtyScheduled",
            "QtyPicked",
            "QtyBackordered",
            "QtyOutstanding",
            "OrderNumber2",
            "_SNValve"
        ]
    }
}

If I take out "_SNValve" then its fine.

Also, i heard in a video that you should take out the "required statement and the list of variable from schema.  No reason was given.  Is this true?

[LaurensM · Accepted solution]

Hi @martinav,

I did some tests on my end and noted down the result below.

Generally the 'FlowWadlConversionNotSupported' is caused by an invalid JSON schema. After some testing the following JSON column structures resulted in an error:

//No type is defined
"ColumnName": {}

//Multiple types are defined
"ColumnName": {
    "type": [
        "string",
        "null"
    ]
}

In your case, defining "_SNValve" as a simple string type should resolve the issue. The Response action will be able to handle the occassional null value for _SNValve:

"_SNValve": {
    "type": "string"
}

This is a bit counterintuitive since you would need to define the JSON schema as ["string", "null"] in a ParseJSON action. A simple JSON type definition such as the case above would fail in a ParseJSON when one of the row contains a null value for that column. However, it seems to run smoothly when using the simple data type schema within the Response action. Unfortunately, I was unable to find any documentation to provide more clarity on this issue.

As for your second question, I only remove the fields from the required section whenever the column will not be present in all rows within the JSON array. That said, from some initial testing this required array seems to have little to no effect in the response action. (at least compared to the ParseJSON action behaviour)

Since it is mainly Power Automate related, I would suggest to check whether any of our experts on the Power Automate forum can confirm / further explain this behaviour.

If this solves your question, would you be so kind as to accept it as a solution & give it a thumbs up.

Thanks!

[martinav]

@LaurensM wrote:

This is a bit counterintuitive since you would need to define the JSON schema as ["string", "null"] in a ParseJSON action.

Wow... you arent even kidding.  Its more than counterintuitive, its just downright absurd.  The fact that I used a parseJSON to validate my schema.  There is no way to refine a schema in a Response action because you cant even load it into your PA and run it if its wrong. 

This shows how invaluable the forums are to resolve issues like this.  It also goes to show that PA has so many holes like this.  There is absolutely no intuitive way to know that a schema would act differently in a parseJSON action as to a Response action.  They are seemingly identical operations, yet they have different and undocumented rules.  I dont know how you (@LaurensM) had one clue how to even know about this difference.  The other issue is even though I am in PA almost daily.  Developing apps start to finish constitutes a very wide breadth of knowledge.  I am not confident that the next time I run across this, I will not again waste HOURS trying to resolve it yet again.  Remembering the simple nuance or even finding a way to notate it for later use is almost impossible to manage.  I will only hope I will be lucky and type a search statement good enough to run across my own posting again.  Its amazing over the last 4 years, how many times I have searched the forums for an issue, to find one of my own posts, just to resolve a reoccurring issue.  

PA has allowed me to create things I would have never been able to create if I was required to know C or some other programming lanugage.  But it sure does have some pitfalls for a LOT of wasted time on seemingly simple problems.  This forum is the ONLY way to navigate these issues.  I have found no other resource that comes close to resolve issues as this forum has.  

Thanks to all who contributed to this issue.