Nanoflows vs Microflows

Nanoflows are client-side logic flows that execute in the user’s browser or on mobile devices. They share the same MDL syntax as microflows but have a different set of capabilities and restrictions.

Key Differences

When to Use Which

Use a microflow when you need to:

• Retrieve data from or commit data to the database
• Call external web services or REST APIs
• Execute Java actions
• Perform batch operations on large data sets
• Use transactions with rollback support

Use a nanoflow when you need to:

• Respond quickly to user actions without server delay
• Perform client-side validation
• Toggle UI state (show/hide elements)
• Navigate between pages
• Work offline on mobile devices

CREATE NANOFLOW Syntax

CREATE [OR REPLACE] NANOFLOW <Module.Name>
  [FOLDER '<path>']
BEGIN
  [<declarations>]
  [<activities>]
  [RETURN <value>;]
END;

The syntax is identical to CREATE MICROFLOW except for the keyword.

Supported Activities in Nanoflows

Object Operations

-- Create an object (in memory only)
$Item = CREATE Sales.CartItem (
  Quantity = 1,
  ProductName = $Product/Name
);

-- Change an object in memory
CHANGE $Item (Quantity = $Item/Quantity + 1);

Calling Other Flows

-- Call another nanoflow
$Result = CALL NANOFLOW Sales.NAV_ValidateCart (Cart = $Cart);

-- Call a microflow (triggers server round-trip)
$ServerResult = CALL MICROFLOW Sales.ACT_SubmitOrder (Order = $Order);

UI Activities

-- Show a page
SHOW PAGE Sales.CartDetail ($Cart = $Cart);

-- Close the current page
CLOSE PAGE;

Validation

VALIDATION FEEDBACK $Item/Quantity MESSAGE 'Quantity must be at least 1';

Logging

LOG INFO 'Cart updated with ' + toString($ItemCount) + ' items';

Control Flow

IF $Cart/ItemCount = 0 THEN
  VALIDATION FEEDBACK $Cart/ItemCount MESSAGE 'Cart is empty';
  RETURN false;
ELSE
  SHOW PAGE Sales.Checkout ($Cart = $Cart);
  RETURN true;
END IF;

Activities NOT Available in Nanoflows

The following activities are server-only and cannot be used in nanoflows:

• RETRIEVE ... FROM Module.Entity WHERE ... (database retrieval)
• COMMIT
• DELETE
• ROLLBACK
• CALL JAVA ACTION
• EXECUTE DATABASE QUERY
• ON ERROR { ... } (full error handler blocks)

SHOW and DESCRIBE

SHOW NANOFLOWS
SHOW NANOFLOWS IN MyModule
DESCRIBE NANOFLOW MyModule.NAV_ShowDetails

DROP

DROP NANOFLOW MyModule.NAV_ShowDetails;

Folder Organization

CREATE NANOFLOW Sales.NAV_OpenCart
FOLDER 'Navigation'
BEGIN
  SHOW PAGE Sales.Cart_Overview ();
END;

MOVE NANOFLOW Sales.NAV_OpenCart TO FOLDER 'UI/Navigation';

Example: Client-Side Validation

CREATE NANOFLOW Sales.NAV_ValidateOrder
FOLDER 'Validation'
BEGIN
  DECLARE $Order Sales.Order;
  DECLARE $IsValid Boolean = true;

  IF $Order/CustomerName = empty THEN
    VALIDATION FEEDBACK $Order/CustomerName MESSAGE 'Customer name is required';
    SET $IsValid = false;
  END IF;

  IF $Order/TotalAmount <= 0 THEN
    VALIDATION FEEDBACK $Order/TotalAmount MESSAGE 'Total must be greater than zero';
    SET $IsValid = false;
  END IF;

  RETURN $IsValid;
END;

Example: Page Navigation

CREATE NANOFLOW Sales.NAV_GoToOrderDetail
BEGIN
  DECLARE $Order Sales.Order;

  SHOW PAGE Sales.Order_Detail ($Order = $Order);
END;