Fix caching problem (#22473)

pkg/tsdb/cloudwatch/credentials.go

@@ -28,7 +28,7 @@ var awsCredentialCache = make(map[string]cache)
 var credentialCacheLock sync.RWMutex
 
 func GetCredentials(dsInfo *DatasourceInfo) (*credentials.Credentials, error) {
-	cacheKey := dsInfo.AccessKey + ":" + dsInfo.Profile + ":" + dsInfo.AssumeRoleArn
+	cacheKey := fmt.Sprintf("%s:%s:%s:%s", dsInfo.AuthType, dsInfo.AccessKey, dsInfo.Profile, dsInfo.AssumeRoleArn)
 	credentialCacheLock.RLock()
 	if _, ok := awsCredentialCache[cacheKey]; ok {
 		if awsCredentialCache[cacheKey].expiration != nil &&

public/app/plugins/datasource/cloudwatch/components/ConfigEditor.tsx

@@ -130,7 +130,12 @@ export class ConfigEditor extends PureComponent<Props, State> {
                 value={authProviderOptions.find(authProvider => authProvider.value === options.jsonData.authType)}
                 options={authProviderOptions}
                 defaultValue={options.jsonData.authType}
-                onChange={onUpdateDatasourceJsonDataOptionSelect(this.props, 'authType')}
+                onChange={option => {
+                  if (options.jsonData.authType === 'arn' && option.value !== 'arn') {
+                    delete this.props.options.jsonData.assumeRoleArn;
+                  }
+                  onUpdateDatasourceJsonDataOptionSelect(this.props, 'authType')(option);
+                }}
               />
             </div>
           </div>