Re-building the Date Workflow

Flow › Chapter 4 walked through date on the command line — a process that takes a format argument and an optional TZ configuration, and produces a string. Time to build that workflow for real.

What you will learn

• How to combine two upstream nodes into a single downstream node
• How DateTime uses configuration (timezone, format) plus a port
• How PromptTemplate stitches values together with named slots

Reset the canvas

This page builds a different shape than the previous one. Open the editor and remove the nodes you no longer need:

• Delete TextProcessor.
• Delete the TextInput node feeding its operation port.

You should be left with just ChatInput and ChatOutput, unconnected.

Step 1: Add a DateTime node

1. Click + and search for Date Time (under Utility).
2. Drop it on the canvas.

Click the new node and configure it:

• operation: current (this is the default — outputs the current time)
• timezone: Europe/Berlin (or whatever zone you like — try Asia/Tokyo)
• format: Y-m-d H:i (PHP date format — year-month-day hour:minute)

DateTime has no required input. It just produces values from its configuration.

Step 2: Add a PromptTemplate node

1. Click + and add a Prompt Template (under Text & Output).
2. Click it to configure.
3. Set template to:

Hi {{ name }}, it's {{ now }} where I'm running.

PromptTemplate creates one input port for each {{ variable }} you reference. So this template gives you two ports: name and now.

Step 3: Wire everything up

┌─────────────┐
│  ChatInput  │
│             │ message
└──────┬──────┘
       │
       │           ┌────────────────┐
       │ name      │ PromptTemplate │
       └──────────▶│                │
                   │ Hi {{name}},   │ prompt   ┌──────────────┐
       ┌──────────▶│ it's {{now}}…  ├─────────▶│  ChatOutput  │
       │ now       │                │          │              │
       │           └────────────────┘          └──────────────┘
┌──────┴──────┐
│  DateTime   │
│ Europe/Berlin│ datetime
│ Y-m-d H:i   │
└─────────────┘

To draw this:

1. ChatInput's message output → PromptTemplate's name input
2. DateTime's datetime output → PromptTemplate's now input
3. PromptTemplate's prompt output → ChatOutput's message input

Step 4: Test

Save and open the Playground. Type Alice.

You should see:

Hi Alice, it's 2026-04-28 14:32 where I'm running.

Send another name. The time updates on each run, because DateTime re-evaluates every time the workflow runs.

What just happened — comparing to Flow Ch. 4

In Flow Chapter 4 we drew this:

TimeZone ──▶  Clock  ──▶ Display
Get Date ──▶
              [Format, TimeZone configured inside]

What you just built is the same shape, with FlowDrop names:

Flow Ch. 4 box	This workflow
Clock (the process)	DateTime node
Format (configured inside)	DateTime's format config
TimeZone (configured inside)	DateTime's timezone config
Get Date (trigger)	DateTime needs no upstream — execution starts it
Display	ChatOutput node

The name input is new — that's the user's name flowing in from ChatInput. PromptTemplate is the glue that combines DateTime's output with that name into a single string.

A small dynamic twist

Try this: DateTime has a timezone input port, not just a configuration value (same idea as Page 3). Add a TextInput with default Asia/Tokyo, wire it to DateTime's timezone input, save, send a message. The greeting now reports Tokyo time instead of Berlin.

Same pattern as before — config holds the default, a port overrides it at runtime.

Why two upstream nodes matter

Until this page, every node had exactly one input flow. Here, PromptTemplate has two parents: ChatInput and DateTime. Both must finish before PromptTemplate runs. FlowDrop figures that out automatically — it walks the edges, finds the dependencies, and runs nodes in the right order.

This is the first place the workflow stops being a single chain and starts being a real graph.

Next

Trigger vs Data Edges → — what about an arrow that fires another node but carries no data?