How do I use JSON function with a repeating section gallery?

[Morke]

Hi

I'm using a gallery and a button to create a repeating section with a couple of dropdowns.

Until now and following a tutorial, I used the following code to concatenate the selected values in it and save it in a SP List column:

This was in the Plus button (OnSelect) to add a row:

Collect(  
NewCollection,  
   {  
      CItemSerialNumber: Text(Last(NewCollection).CItemSerialNumber + 1),  
      Clevel: "",  
      Ctc: "",  
     Cdescription: ""  
  }  
)

This was in the Save button (OnSelect):

UpdateContext(  
    {  
        NewItemsString: Concat(  
            Gallery2.AllItems,  
            Concatenate(
                "LUN:",TextInput2.Text,";"
                ,"Size:",Text(Dropdown8.Selected.Size),";",
                "SKU",Dropdown9.Selected.Value,";",
                "|"
            )  
        )  
    }  
)

And this was on the Default property of the Data Card holding the Gallery:

NewItemsString

However, in Flow, processing that single string composed of concatenated things in it has become troublesome, so I started looking for an alternative and I found the JSON function which saves the string in JSON format, which would be a lot easier to handle in Flow.
But I can't seem to understand how to translate the previously posted logic to JSON...
Can you help me?
Thanks in advance.

[v-siky-msft]

Hi @Morke ,

Could you please share more details about what do you want to implement in flow?

I can understand what do you want to achieve in PowerApps since I found the tutorial, but what do you want to do in flow? Do you just want to pass the concatenated string to the flow? I think you can directly pass the concatenated string to flow.

If you want to know how to compose the concatenated string from the Array in flow, please try this:

First to use 'Append to array variable' action to create an array that concatenates each field and value, Then use Join data operator action to return a string from an Array separated by a ”|“.

Result:

Hope this helps,

Sik

[Morke]

Thank you for your reply. I'll try your solution and let you know if it works for me.

As for what I want to do in Flow, I need to supply an array of arrays variable to an ARM Template (which is just a glorificated JSON Azure uses)
Since I was having trouble understanding how to create an array of arrays from a single concatenated string that doesn't have any formatting besides the separators ( ";" between each component of an item and "|" between each item), I started to research on how would the best approach be, and maybe sending a JSOn formated string to Flow instead of a simple string would make things easier when using it.
But i'm not sure and that's the reason of this post.

The reason I need an array of arrays is that the ARM Template has a Copy function that lets you loop through an array of arrays (received as a parameter variable).

[TiagoFreire]

Is there a specific reason for not using PowerApps JSON() function? 

You can serialize your collection directly to JSON on PowerApps, and submit the JSON string to power Automate. 

The you can just Parse JSON() on Power Automate to work with the data as an object and make any manipulation you need to make the ARM Template. 

[Morke]

Yes, there's a specific reason:
My lack of knowledge, hahahaha.
No, seriously. That string is created by a concatenate of a Repeating Gallery. I followed a tutorial to do it but I'm struggling on how to transform the current way of doing it to use JSON instead.

[TiagoFreire]

JSON() can serialize any collection or Record. 

I usually use it in conjunction with Set(), so I can debug the JSON string on PowerApps end before I submit. 

simple case: 

Set( json_var, JSON(MyCollection, JsonFormat.IgnoreUnsupportedTypes));

Then I submit it to Power Automate:

PowerAutomateFunction.Run(json_var);

On Power Automate: 

A single params parameter receives the JSON string.

the Parse JSON action interprets the JSON string according to a JSON schema and makes it available to the Flow as actionable objects. It also has a convenient schema generator, all you have to do is supply the schema generator with a data sample, and it generates the schema for you. 

Advanced use: 

Instead of submitting multiple parameters in PowerApps side when you PowerAutomateFunction.Run(), you can pack everything in a single JSON parameter instead. 

Set(json_var,
    JSON(  //you can write a literal object here and pack several variables or collections on a single string
        {

            savelocation: "/locationdata/",

            data: mydatacollection

        },
        JsonFormat.IgnoreUnsupportedTypes

    )
)

One must remember to update the schema on Parse JSON once the submitted data changes, to access the data on that side. 

Using this technique of packing everything in a single JSON string, it becomes unnecessary to remove and re-add the Flow on PowerApps if you change the parameters later on. 

[Morke]

@TiagoFreire Thank you, that's very helpful. I appreciate it.
I don't want to ask for a step by step guide or to hand me over the solution, but I might need a bit more of guidance to accomplish what I intend to.
Ok so you are creating a JSON object and saving that into a variable. No problem there.
However, where do I use the JSON function in my solution to do that, considering I'm using a repeating gallery?

In here, with this Plus button in this Data card and with this code in the OnSelect Property, I understand that I'm creating a collection every time someone presses it:

Collect(  
NewCollection,  
   {  
      CItemSerialNumber: Text(Last(NewCollection).CItemSerialNumber + 1),  
      Clevel: "",  
      Ctc: "",  
     Cdescription: ""  
  }  

  This gallery has "NewCollection" collection as a DataSource so every time someone presses the button an creates a new NewCollection, a new "row" replicates itself:

if you want to save what you created, you press the Save button on the DataCard which has this OnSelect Code. This creates or (updates if it already exists) NewItemsString variable, which is a concatenation of all gallery items, which are, in turn, being concatenated as well:

UpdateContext(  
    {  
        NewItemsString: Concat(  
            Gallery2.AllItems,  
            Concatenate(
                TextInput2.Text,
                ";",Text(Dropdown8.Selected.Size),
                ";",
		Dropdown9.Selected.Value,
                ";",
                "|"
            )  
        )  
    }  
);

Lastly, the DataCard "Default" is set to NewItemsString variable, which gets updated everytime you press the Save button.


I suspect I need to modify the Save button which is the one creating a concatenated string. Instead, I need to use the JSON function to create the function object with the current gallery items
However, I'm not sure in which way I need to modify it.
Can you point me in the right direction?

[TiagoFreire · Accepted solution]

From your code, it seems that you are submitting the entire data from your NewCollection data source to Power Automate when you click on the Save Button. I will start from this assumption.

Gallery2.AllItems is just pointing to NewCollection, but with a layer of indirection. As you are Collect()ing to the data source, you can reference it directly to serialize to JSON.

On your Save Button, you can just: 

Set(NewCollectionJson, JSON(NewCollection, JSONFormat.IgnoreUnsupportedTypes));

Read the reference, for the JSON function. you can also use JSONFormat.IndentFour to display json for human eyes.

Check the generated JSON on a Label. If it is looking right, also add your submit function to the save button: 

MyPowerAutomateSaveFunction.Run(NewCollectionJSON);

Note that you are sending a single parameter of type string. 

From that point on, is just going to Power Automate and add Parse JSON there to interpret the json string back into an object. 

[v-siky-msft]

Hi @Morke ,

My above flow is to concatenate the Array to be a string by separators(; and |) as what you do in PowerApps.

However, I just found you just want to create an array from that concatenated string, right?

If so, I think you just pass the NewCollection to Flow by JSON function, and @TiagoFreire has provide such workaround, I think it should make sense for your case.

Please feel free to post back if you still need assistance.

Sik

[Robaddy2]

I am new to this and am in the same boat. The only difference is I am trying to submit the data from the gallery to my SharePoint single line text. I am not sure how to implement JSON to send the data as a string to SharePoint list.

Do I add the code for JSON to the code or to the item property of the gallery