UI: Device provisioning autogenerate device key and secret

@@ -403,3 +403,15 @@ export function deepTrim<T>(obj: T): T {
     return acc;
   }, (Array.isArray(obj) ? [] : {}) as T);
 }
+
+export function generateSecret(length?: number): string {
+  if (isUndefined(length) || length == null) {
+    length = 1;
+  }
+  const l = length > 10 ? 10 : length;
+  const str = Math.random().toString(36).substr(2, l);
+  if (str.length >= length) {
+    return str;
+  }
+  return str.concat(generateSecret(length - str.length));
+}

@@ -32,7 +32,7 @@ import {
   DeviceProvisionType,
   deviceProvisionTypeTranslationMap
 } from "@shared/models/device.models";
-import { isDefinedAndNotNull } from "@core/utils";
+import { generateSecret, isDefinedAndNotNull } from '@core/utils';
 
 @Component({
   selector: 'tb-device-profile-provision-configuration',
@@ -85,10 +85,18 @@ export class DeviceProfileProvisionConfigurationComponent implements ControlValu
     this.provisionConfigurationFormGroup.get('type').valueChanges.subscribe((type) => {
       if (type === DeviceProvisionType.DISABLED) {
         this.provisionConfigurationFormGroup.get('provisionDeviceSecret').disable({emitEvent: false});
-        this.provisionConfigurationFormGroup.get('provisionDeviceSecret').patchValue(null,{emitEvent: false});
+        this.provisionConfigurationFormGroup.get('provisionDeviceSecret').patchValue(null, {emitEvent: false});
         this.provisionConfigurationFormGroup.get('provisionDeviceKey').disable({emitEvent: false});
         this.provisionConfigurationFormGroup.get('provisionDeviceKey').patchValue(null);
       } else {
+        const provisionDeviceSecret: string = this.provisionConfigurationFormGroup.get('provisionDeviceSecret').value;
+        if (!provisionDeviceSecret || !provisionDeviceSecret.length) {
+          this.provisionConfigurationFormGroup.get('provisionDeviceSecret').patchValue(generateSecret(20), {emitEvent: false});
+        }
+        const provisionDeviceKey: string = this.provisionConfigurationFormGroup.get('provisionDeviceKey').value;
+        if (!provisionDeviceKey || !provisionDeviceKey.length) {
+          this.provisionConfigurationFormGroup.get('provisionDeviceKey').patchValue(generateSecret(20), {emitEvent: false});
+        }
         this.provisionConfigurationFormGroup.get('provisionDeviceSecret').enable({emitEvent: false});
         this.provisionConfigurationFormGroup.get('provisionDeviceKey').enable({emitEvent: false});
       }