config(customization): customization override (aws#6545)

## Problem

https://github.com/aws/aws-toolkit-vscode/blob/master/packages/core/src/codewhisperer/util/customizationUtil.ts#L116-L130

The flaw of previous implementation won't override customization if
users have selected one.

The team is asking 
1. Ability to override regardless users are with a customization or not
2. Should respect users' selection afterward when users switch back to
the customization they prefer
3. When ab service provides a new override customization arn, plugins
should be able to do override again

```
// as long as there is a customization selected, override will not happen no matter what
 if (selectedCustomization && selectedCustomization.name !== '') {
        return selectedCustomization
    } else {
        const customizationFeature = FeatureConfigProvider.getFeature(Features.customizationArnOverride)
        const arnOverride = customizationFeature?.value.stringValue
        const customizationOverrideName = customizationFeature?.variation
        if (arnOverride === undefined) {
            return baseCustomization
        } else {
            return {
                arn: arnOverride,
                name: customizationOverrideName,
                description: baseCustomization.description,
            }
        }

```

## Solution
1. Persist a value of "previous override arn" and do override when the
provided customization arn is different than "previous override arn"



---

- Treat all work as PUBLIC. Private `feature/x` branches will not be
squash-merged at release time.
- Your code changes must meet the guidelines in
[CONTRIBUTING.md](https://github.com/aws/aws-toolkit-vscode/blob/master/CONTRIBUTING.md#guidelines).
- License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: Will-ShaoHua

packages/core/src/codewhisperer/util/customizationUtil.ts

@@ -18,7 +18,6 @@ import { showMessageWithUrl } from '../../shared/utilities/messages'
 import { parse } from '@aws-sdk/util-arn-parser'
 import { Commands } from '../../shared/vscode/commands2'
 import { vsCodeState } from '../models/model'
-import { FeatureConfigProvider, Features } from '../../shared/featureConfig'
 
 /**
  *
@@ -92,10 +91,7 @@ export const baseCustomization = {
 }
 
 /**
- * Gets the customization that should be used for user requests. If a user has manually selected
- * a customization, always respect that choice. If not, check if the user is part of an AB
- * group assigned a specific customization. If so, use that customization. If not, use the
- * base customization.
+ * @returns customization selected by users, `baseCustomization` if none is selected
  */
 export const getSelectedCustomization = (): Customization => {
     if (
@@ -116,25 +112,27 @@ export const getSelectedCustomization = (): Customization => {
     if (selectedCustomization && selectedCustomization.name !== '') {
         return selectedCustomization
     } else {
-        const customizationFeature = FeatureConfigProvider.getFeature(Features.customizationArnOverride)
-        const arnOverride = customizationFeature?.value.stringValue
-        const customizationOverrideName = customizationFeature?.variation
-        if (arnOverride === undefined) {
-            return baseCustomization
-        } else {
-            return {
-                arn: arnOverride,
-                name: customizationOverrideName,
-                description: baseCustomization.description,
-            }
-        }
+        return baseCustomization
     }
 }
 
-export const setSelectedCustomization = async (customization: Customization) => {
+/**
+ * @param customization customization to select
+ * @param isOverride if the API call is made from us (Q) but not users' intent, set isOverride to TRUE
+ * Override happens when ALL following conditions are met
+ *  1. service returns non-empty override customization arn, refer to [featureConfig.ts]
+ *  2. the override customization arn is different from the previous override customization if any. The purpose is to only do override once on users' behalf.
+ */
+export const setSelectedCustomization = async (customization: Customization, isOverride: boolean = false) => {
     if (!AuthUtil.instance.isValidEnterpriseSsoInUse() || !AuthUtil.instance.conn) {
         return
     }
+    if (isOverride) {
+        const previousOverride = globals.globalState.tryGet<string>('aws.amazonq.customization.override', String)
+        if (customization.arn === previousOverride) {
+            return
+        }
+    }
     const selectedCustomizationObj = globals.globalState.tryGet<{ [label: string]: Customization }>(
         'CODEWHISPERER_SELECTED_CUSTOMIZATION',
         Object,
@@ -144,6 +142,9 @@ export const setSelectedCustomization = async (customization: Customization) =>
     getLogger().debug(`Selected customization ${customization.name} for ${AuthUtil.instance.conn.label}`)
 
     await globals.globalState.update('CODEWHISPERER_SELECTED_CUSTOMIZATION', selectedCustomizationObj)
+    if (isOverride) {
+        await globals.globalState.update('aws.amazonq.customization.override', customization.arn)
+    }
     vsCodeState.isFreeTierLimitReached = false
     await Commands.tryExecute('aws.amazonq.refreshStatusBar')
 }

packages/core/src/shared/featureConfig.ts

@@ -21,6 +21,7 @@ import { getClientId, getOperatingSystem } from './telemetry/util'
 import { extensionVersion } from './vscode/env'
 import { telemetry } from './telemetry/telemetry'
 import { Commands } from './vscode/commands2'
+import { setSelectedCustomization } from '../codewhisperer/util/customizationUtil'
 
 const localize = nls.loadMessageBundle()
 
@@ -148,7 +149,7 @@ export class FeatureConfigProvider {
                 if (isBuilderIdConnection(AuthUtil.instance.conn)) {
                     this.featureConfigs.delete(Features.customizationArnOverride)
                 } else if (isIdcSsoConnection(AuthUtil.instance.conn)) {
-                    let availableCustomizations = undefined
+                    let availableCustomizations: Customization[] = []
                     try {
                         const items: Customization[] = []
                         const response = await client.listAvailableCustomizations()
@@ -157,17 +158,20 @@ export class FeatureConfigProvider {
                         )) {
                             items.push(...customizations)
                         }
-                        availableCustomizations = items.map((c) => c.arn)
+                        availableCustomizations = items
                     } catch (e) {
                         getLogger().debug('amazonq: Failed to list available customizations')
                     }
 
                     // If customizationArn from A/B is not available in listAvailableCustomizations response, don't use this value
-                    if (!availableCustomizations?.includes(customizationArnOverride)) {
+                    const targetCustomization = availableCustomizations?.find((c) => c.arn === customizationArnOverride)
+                    if (!targetCustomization) {
                         getLogger().debug(
                             `Customization arn ${customizationArnOverride} not available in listAvailableCustomizations, not using`
                         )
                         this.featureConfigs.delete(Features.customizationArnOverride)
+                    } else {
+                        await setSelectedCustomization(targetCustomization, true)
                     }
 
                     await vscode.commands.executeCommand('aws.amazonq.refreshStatusBar')

packages/core/src/shared/globalState.ts

@@ -45,6 +45,7 @@ export type globalKey =
     | 'aws.toolkit.amazonq.dismissed'
     | 'aws.toolkit.amazonqInstall.dismissed'
     | 'aws.amazonq.workspaceIndexToggleOn'
+    | 'aws.amazonq.customization.override'
     // Deprecated/legacy names. New keys should start with "aws.".
     | '#sessionCreationDates' // Legacy name from `ssoAccessTokenProvider.ts`.
     | 'CODECATALYST_RECONNECT'

packages/core/src/test/amazonq/customizationUtil.test.ts

@@ -82,16 +82,39 @@ describe('CodeWhisperer-customizationUtils', function () {
         assert.strictEqual(actualCustomization.name, selectedCustomization.name)
     })
 
-    it('Returns AB customization', async function () {
-        sinon.stub(AuthUtil.instance, 'isValidEnterpriseSsoInUse').returns(true)
+    it(`setSelectedCustomization should set to the customization provided if override option is false or not specified`, async function () {
+        await setSelectedCustomization({ arn: 'FOO' }, false)
+        assert.strictEqual(getSelectedCustomization().arn, 'FOO')
+
+        await setSelectedCustomization({ arn: 'BAR' })
+        assert.strictEqual(getSelectedCustomization().arn, 'BAR')
+
+        await setSelectedCustomization({ arn: 'BAZ' })
+        assert.strictEqual(getSelectedCustomization().arn, 'BAZ')
+
+        await setSelectedCustomization({ arn: 'QOO' }, false)
+        assert.strictEqual(getSelectedCustomization().arn, 'QOO')
+    })
+
+    it(`setSelectedCustomization should only set to the customization provided once for override per customization arn if override is true`, async function () {
+        await setSelectedCustomization({ arn: 'OVERRIDE' }, true)
+        assert.strictEqual(getSelectedCustomization().arn, 'OVERRIDE')
+
+        await setSelectedCustomization({ arn: 'FOO' }, false)
+        assert.strictEqual(getSelectedCustomization().arn, 'FOO')
+
+        // Should NOT override only happen per customization arn
+        await setSelectedCustomization({ arn: 'OVERRIDE' }, true)
+        assert.strictEqual(getSelectedCustomization().arn, 'FOO')
 
-        await setSelectedCustomization({
-            arn: '',
-            name: '',
-        })
+        await setSelectedCustomization({ arn: 'FOO' }, false)
+        assert.strictEqual(getSelectedCustomization().arn, 'FOO')
 
-        const returnedCustomization = getSelectedCustomization()
+        await setSelectedCustomization({ arn: 'BAR' }, false)
+        assert.strictEqual(getSelectedCustomization().arn, 'BAR')
 
-        assert.strictEqual(returnedCustomization.name, featureCustomization.name)
+        // Sould override as it's a different arn
+        await setSelectedCustomization({ arn: 'OVERRIDE_V2' }, true)
+        assert.strictEqual(getSelectedCustomization().arn, 'OVERRIDE_V2')
     })
 })