Provide scaler for Azure Data Explorer

[tomkerkhove]

A clear and concise description of what scaler you'd like to use and how you'd want to use it:

• Scaler Source: Azure Data Explorer
• How do you want to scale: Scale based on a Kusto query
• Authentication: TBD
• SDK: https://docs.microsoft.com/en-us/azure/data-explorer/kusto/api/golang/kusto-golang-client-library

[yasiboni-max]

It's a really good improvement. I'd like to work on this one.

[tomkerkhove]

Awesome, thanks a ton @yasiboni-max!

[RamCohen]

Hi. Was there any progress made ?
Would like to take this on.

[tomkerkhove]

I haven't heard from @yasiboni-max so if you'd like to work on it - Be my guest!

Ok for you @yasiboni-max ?

[yasiboni-max]

@tomkerkhove I actually finished the implementation, but then I saw that you asked to use the SDK so I started to do so.
Currently I have an issue with passing a predefined query to kusto client.

[yasiboni-max]

I'm looking for a workaround for this issue so I'll be able to complete this PR entirely.
@tomkerkhove - as far as you concern, do I have to use Kusto SDK or would it be possible to implement light Rest client for this?

[RamCohen]

Try this: // GetADXSingleRowFromQuery returns the only row from an ADX query result. If there are more rows, an error is returned. func GetADXSingleRowFromQuery(ctx context.Context, query string, client querier) (*table.Row, error) { // Execute the query. iter, err := client.Query(ctx, "database", kusto.NewStmt("", kusto. UnsafeStmt(unsafe.Stmt { true, false})).UnsafeAdd(query)) if err != nil { return nil, fmt.Errorf("failed to execute query %s: %v", query, err) } defer iter.Stop() // Get the first (and only result) that should have only a single numerical column. row, err := iter.Next() if err != nil { return nil, fmt.Errorf("failed to get query %s result: %v", query, err) } _, err = iter.Next() if (err != io.EOF) { return nil, fmt.Errorf("Query %s result had more than a single result row", query) } return row, nil }

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On Mon, Jan 31, 2022 at 4:59 PM yasiboni-max ***@***.***> wrote: I'm looking for a workaround for this issue so I'll be able to complete this PR entirely. — Reply to this email directly, view it on GitHub <#1488 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AATJ7GQ5WGLI3VPVHX2X5G3UY2PU5ANCNFSM4VY6KJCQ> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you commented.Message ID: ***@***.***>

[yasiboni-max]

Hi @tomkerkhove, my e2e test requires some setup in the subscription that being used for that:

• Kusto cluster
• Kusto database
• Assign the necessary role to the AAD app & MSI that pod identity use
• Expose few values as environment variables.

Can you please elaborate with the right procedure to do so? I didn't find (or missed) the guidelines in the contribution guide for that.

[tomkerkhove]

We don't allow contributors to do this for now but if you can provide some more information then I'm happy to do everything that is required.

[yasiboni-max]

Sure, no problem. Few requirements for e2e:

• Provision Data Explorer Cluster.
• Create Database inside that cluster.
• Assign "Database viewer" role to AAD app & MSI that pod identity use (link).
• Expose database name as env var "TEST_DATA_EXPLORER_DB" in e2e environment.
• Expose cluster endpoint uri as env var "TEST_DATA_EXPLORER_ENDPOINT" in e2e environment.

Edit: Alternatively, you can send me database name and cluster endpoint and I'll add them to e2e test files

keda pr: #2627
keda-docs pr: kedacore/keda-docs#658

[tomkerkhove]

e2e variables are added in #2643 but with different names.

Do note that the URI is currently the URI and not the Data Ingestion URI:

[tomkerkhove]

Thank you for the contribution @yasiboni 🎉