Use v5 API host in QnAMakerDialog or construct v4 API host

[stevengum]

Do not merge without review from @vipeketi

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Fixes breaking change in #1999 while still addressing #1885

Description

This PR changes the logic in QnAMakerDialog.getQnAClient() to use the dialog instance's hostName if it contains 'qnamaker/v5' otherwise use the pre-#1999 behavior of constructing a v4 API endpoint with a template literal.

This PR also adds missing validation to the QnAMakerDialog constructor (C#) and fixes the doc string on the QnAMakerEndpoint interface.

Specific Changes

• Use hostName if it is a v5 API host, otherwise construct v4 API host value
• Added unit tests for QnAMakerDialog.getQnAClient()
• Add missing validation checks for QnAMakerDialog constructor
• Add tests for new valdiation in QnAMakerDialog
• Fix QnAMakerEndpoint doc string on host
• Remove unused imports in QnAMaker

[coveralls]

Pull Request Test Coverage Report for Build 121114

• 20 of 22 (90.91%) changed or added relevant lines in 2 files are covered.
• 9 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.04%) to 67.259%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
libraries/botbuilder-ai/src/qnaMakerDialog.ts	19	21	90.48%

Files with Coverage Reduction	New Missed Lines	%
libraries/botframework-streaming/src/webSocket/webSocketTransport.ts	2	80.65%
libraries/botframework-streaming/src/webSocket/webSocketServer.ts	7	66.67%

Totals
Change from base Build 119935:	-0.04%
Covered Lines:	10332
Relevant Lines:	14534

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💛 - Coveralls

[vipeketi]

As discussed offline lets us hold this PR, as we have PR lined up which has conflict.

[vipeketi]

The hostname format for QnAMaker V5 also need to be accommodated. Sample hostname for QnAMaker V5 is https://qnamaker-acom.azure.com/qnamaker/v5.0-preview.1.

[stevengum]

@vipeketi, per our offline discussions and the internal doc, what if we look for "qnamaker/v5.0" in this.hostName?

private getQnAClient(): QnAMaker {
    const host = this.hostName.includes('qnamaker/v5.0')
                 ? this.hostName
                 : this.constructHttpsHostName(this.hostName);

    const endpoint = {
        knowledgeBaseId: this.knowledgeBaseId,
        endpointKey: this.endpointKey,
        host
    };
    return new QnAMaker(endpoint);
}

I'll iterate a couple of times to make the code clearer (e.g. change constructHttpsHostName() to constructV4ApiHost())

[stevengum]

@vipeketi, here is the latest commit that supports the old behavior around constructing a v4 API endpoint while first inspecting to see if the endpoint is for the v5 API ("qnamaker/v5")

[vipeketi]

v5 handling looks good to me. When source code is downloaded from portal , the appsettings pre-populate complete url like https://xxx.azurewebsites.com/qnamaker. Can we skip just the hostname as value for this.hostName.

[stevengum]

We can't skip the template literal because that's a breaking change, but we can add logic to examine the provided value:

If the hostname looks like this: xxx.azurewebsites.net, then it's probably in the appsettings of a downloaded or deployed bot through Azure. We can apply the logic from your recent PR to the samples: microsoft/BotBuilder-Samples@b834e98.

If it looks like https://xxx.azurewebsites.net/qnamaker, then it's probably gathered from the QnAMaker portal, and it doesn't need to be touched up in this case.

[vipeketi]

If we can accomodate support for https://xxx.azurewebsites.net/qnamaker and qnamaker/v5.0, I am good with the changes.

[vipeketi]

Approved