topic Re: Navigator window not displaying function input parameters. Custom Connector for Power BI in Developer

Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Thu, 08 Dec 2022 08:36:16 GMT

Hi,

I am trying to create a custom connector for Power BI. I have followed the documentation on how to set up

a Navigation Table. The table will navigate to three different functions.

I have set up the code accordingly. However, the UI for the function inputs is not generated in the Navigator window. Rather I am seeing this:

I see the UI just fine in the Power Query Editor. Here is my implementation of some test code:

[DataSource.Kind="PQExtension1", Publish="PQExtension1.Publish"] shared PQExtension1.Contents = () as table => let objects = #table( {"Name", "Key", "Data", "ItemKind", "ItemName", "IsLeaf"},{ {"Item1", "item1", PQExtension1.GetSeries, "Function", "Function", true} }), NavTable = Table.ToNavigationTable(objects, {"Key"}, "Name", "Data", "ItemKind", "ItemName", "IsLeaf") in NavTable; [DataSource.Kind = "PQExtension1"] shared PQExtension1.GetSeries = () => Value.ReplaceType(HelloWorldImpl, HelloWorldType) HelloWorldType = type function ( message as (type text meta [ Documentation.FieldCaption = "Message", Documentation.FieldDescription = "Text to display", Documentation.SampleValues = {"Hello world", "Hola mundo"} ]), optional count as (type number meta [ Documentation.FieldCaption = "Count", Documentation.FieldDescription = "Number of times to repeat the message", Documentation.AllowedValues = { 1, 2, 3 } ])) as table meta [ Documentation.Name = "Hello - Name", Documentation.LongDescription = "Hello - Long Description", Documentation.Examples = {[ Description = "Returns a table with 'Hello world' repeated 2 times", Code = "HelloWorldWithDocs.Contents(""Hello world"", 2)", Result = "#table({""Column1""}, {{""Hello world""}, {""Hello world""}})" ],[ Description = "Another example, new message, new count!", Code = "HelloWorldWithDocs.Contents(""Goodbye"", 1)", Result = "#table({""Column1""}, {{""Goodbye""}})" ]} ]; HelloWorldImpl = (message as text, optional count as number) as table => let _count = if (count <> null) then count else 5, listOfMessages = List.Repeat({message}, _count), table = Table.FromList(listOfMessages, Splitter.SplitByNothing()) in table;

I appreciate any help on this. I have seen similar posts here in the Power BI forum but clear solutions have not been given.

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Fri, 09 Dec 2022 06:22:35 GMT

Hi @Anonymous ,

Please refer the following links to get it:

Handling navigation for Power Query connectors | Microsoft Docs

shared NavigationTable.Simple = () => let objects = #table( {"Name", "Key", "Data", "ItemKind", "ItemName", "IsLeaf"},{ {"Item1", "item1", #table({"Column1"}, {{"Item1"}}), "Table", "Table", true}, {"Item2", "item2", #table({"Column1"}, {{"Item2"}}), "Table", "Table", true}, {"Item3", "item3", FunctionCallThatReturnsATable(), "Table", "Table", true}, {"MyFunction", "myfunction", AnotherFunction.Contents, "Function", "Function", true} }), NavTable = Table.ToNavigationTable(objects, {"Key"}, "Name", "Data", "ItemKind", "ItemName", "IsLeaf") in NavTable; shared FunctionCallThatReturnsATable = () => #table({"DynamicColumn"}, {{"Dynamic Value"}});

Custom Connector and Navigation Tables

GetRows = () => if (state <> null) then state else let list = listFunction(), withName = Table.FromRecords(list, {"Name", "ItemKind", "Parameters"}, MissingField.UseNull), withData = Table.AddColumn(withName, "Data", each dataFunction([Name], [Parameters])), withItemName = Table.AddColumn(withData, "ItemName", each if [Parameters] = null or Record.FieldCount([Parameters]) = 0 then "Table" else null), withoutParameters = Table.RemoveColumns(withItemName, {"Parameters"}), withIsLeaf = Table.AddColumn(withoutParameters, "IsLeaf", each isLeaf), navTable = Table.ToNavigationTable(withIsLeaf, {"Name"}, "Name", "Data", "ItemKind", "ItemName", "IsLeaf") in navTable

Best Regards

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Fri, 09 Dec 2022 06:58:46 GMT

Hi,

The examples you have given are with functions that does not implement parameters. I have implemented the NavigationTable function from Handling navigation for Power Query connectors | Microsoft Docs. For instance, if I add a parameter to FunctionCallThatReturnATable then I get the same "No Paramters Specified"-Window in the Navigator. Why does the Preview window not allow me to generate the function UI. In the Power Query editor it works just fine.

shared NavigationTable.Simple = () => let objects = #table( {"Name", "Key", "Data", "ItemKind", "ItemName", "IsLeaf"},{ {"Item1", "item1", #table({"Column1"}, {{"Item1"}}), "Table", "Table", true}, {"Item2", "item2", #table({"Column1"}, {{"Item2"}}), "Table", "Table", true}, {"Item3", "item3", (t as text) => FunctionCallThatReturnsATable(t), "Table", "Table", true}, {"MyFunction", "myfunction", AnotherFunction.Contents, "Function", "Function", true} }), NavTable = Table.ToNavigationTable(objects, {"Key"}, "Name", "Data", "ItemKind", "ItemName", "IsLeaf") in NavTable; shared FunctionCallThatReturnsATable = (t as text) => #table({"DynamicColumn"}, {{t}});

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Fri, 09 Dec 2022 07:38:39 GMT

Hi @Anonymous ,

Please review the following link, hope it can help you.

PowerBIRESTAPI

Best Regards

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Fri, 09 Dec 2022 08:00:14 GMT

Thank you, really appreciate the help! I will check it out.

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Fri, 09 Dec 2022 10:14:19 GMT

So I found a solution from the PowerBI REST API connector project. Basically you need a special implementation of the Table.ToNavigationTable function. It seems that you need to delete the "Preview.DelayColumn = itemNameColumn" from Table.ToNavigationTable .

This implementation of the navigation table works:

Table.ForceToNavigationTable = ( table as table, keyColumns as list, nameColumn as text, dataColumn as text, itemKindColumn as text, itemNameColumn as text, isLeafColumn as text ) as table => let tableType = Value.Type(table), newTableType = Type.AddTableKey(tableType, keyColumns, true) meta [ NavigationTable.NameColumn = nameColumn, NavigationTable.DataColumn = dataColumn, NavigationTable.ItemKindColumn = itemKindColumn, NavigationTable.IsLeafColumn = isLeafColumn ], navigationTable = Value.ReplaceType(table, newTableType) in navigationTable;

The only problem I have now is that the documentation is not shown in the Navigator window:

In the Power Query Editor it looks like this:

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

Anonymous — Mon, 12 Dec 2022 01:31:04 GMT

Hi @Anonymous ,

It's glad to hear that your problem has been resolved. And thanks for sharing your solution here. Thank you.

Best Regards

Re: Navigator window not displaying function input parameters. Custom Connector for Power BI

trello — Wed, 01 Feb 2023 09:18:38 GMT

Hi, I have a similar problem.

My function has a record type parameter like this

but in the navigation table it looks like this