fix: [#4568] scoreThreshold no longer works in 4.17.0 and later

libraries/botbuilder-ai/src/qnaMaker.ts

@@ -270,6 +270,7 @@ export class QnAMaker implements QnAMakerClient, QnAMakerTelemetryClient {
     ): Promise<QnAMakerResults> {
         const question: string = this.getTrimmedMessageText(context);
         const queryOptions: QnAMakerOptions = { ...this._options, ...options } as QnAMakerOptions;
+        const queryResult: QnAMakerResult[] = [] as QnAMakerResult[];
 
         this.generateAnswerUtils.validateOptions(queryOptions);
 
@@ -279,19 +280,25 @@ export class QnAMaker implements QnAMakerClient, QnAMakerTelemetryClient {
             result = await this.generateAnswerUtils.queryQnaServiceRaw(this.endpoint, question, queryOptions);
         }
 
+        const sortedQnaAnswers: QnAMakerResult[] = GenerateAnswerUtils.sortAnswersWithinThreshold(
+            result?.answers,
+            queryOptions
+        );
+        queryResult.push(...sortedQnaAnswers);
+
         if (!result) {
             return result;
         }
 
         await Promise.all([
             // Log telemetry
-            this.onQnaResults(result?.answers, context, telemetryProperties, telemetryMetrics),
-            this.generateAnswerUtils.emitTraceInfo(context, result?.answers, queryOptions),
+            this.onQnaResults(queryResult, context, telemetryProperties, telemetryMetrics),
+            this.generateAnswerUtils.emitTraceInfo(context, queryResult, queryOptions),
         ]);
 
         const qnaResponse: QnAMakerResults = {
             activeLearningEnabled: result.activeLearningEnabled,
-            answers: result?.answers,
+            answers: queryResult,
         };
 
         return qnaResponse;

libraries/botbuilder-ai/src/qnamaker-utils/generateAnswerUtils.ts

@@ -159,6 +159,30 @@ export class GenerateAnswerUtils {
         }
     }
 
+    /**
+     * Sorts all QnAMakerResult from highest-to-lowest scoring.
+     * Filters QnAMakerResults within threshold specified (default threshold: .001).
+     *
+     * @param {QnAMakerResult[]} answers Answers returned by QnA Maker.
+     * @param {QnAMakerOptions} queryOptions (Optional) The options for the QnA Maker knowledge base. If null, constructor option is used for this instance.
+     * @returns {QnAMakerResult[]} the sorted and filtered results.
+     */
+    static sortAnswersWithinThreshold(
+        answers: QnAMakerResult[] = [] as QnAMakerResult[],
+        queryOptions: QnAMakerOptions
+    ): QnAMakerResult[] {
+        const minScore: number = typeof queryOptions.scoreThreshold === 'number' ? queryOptions.scoreThreshold : 0.001;
+
+        if (answers.length === 1 && answers[0].id === -1) {
+            // if the answer is the default answer, don't filter it by score.
+            return answers;
+        }
+
+        return answers
+            .filter((ans: QnAMakerResult) => ans.score >= minScore)
+            .sort((a: QnAMakerResult, b: QnAMakerResult) => b.score - a.score);
+    }
+
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     private formatQnaResult(qnaResult: QnAMakerResults | any): QnAMakerResults {
         qnaResult.answers = qnaResult.answers.map((answer: QnAMakerResult & { qnaId?: number }) => {