How To Execute Multiple Routes with MultiPipe

How To Execute Multiple Routes With MultiPipe

Purpose

Use MultiPipe when all matching branches should execute instead of selecting only one.

This is the GraphK tool for fan-out behavior across multiple matching routes.

What Does MultiPipe Do?

graphk.MultiPipe extends BranchPipe, but instead of choosing one matching branch, it:

1. resolves all matching branch indices
2. orders the selected matches
3. executes every selected branch in that order

When Should You Use It?

Good use cases:

• run several matching handlers
• apply multiple route-specific transformations
• execute parallel-in-concept branches sequentially in one pipeline
• fan out work to all matching route groups

Use MultiPipe when many routes should run. Use BranchPipe when only one route should run.

Order Policies

Important constants:

• MultiPipe.ORDER_STORED
• MultiPipe.ORDER_RANDOM

ORDER_STORED

Use when:

• execution should follow branch definition order
• behavior should remain deterministic

ORDER_RANDOM

Use when:

• execution order can vary intentionally
• or when randomness is seeded for controlled demonstration

Minimal Example

import graphk


pipe = graphk.MultiPipe(
    order_policy=graphk.MultiPipe.ORDER_STORED,
    nodes=[
        (
            graphk.Matcher(task="route"),
            graphk.SequencePipe(nodes=[graphk.demo.RouteNode("A")]),
        ),
        (
            graphk.Matcher(task="route"),
            graphk.SequencePipe(nodes=[graphk.demo.RouteNode("B")]),
        ),
    ],
)

pipeline = graphk.SequencePipe(nodes=[pipe])
session = graphk.Session(task="route")
runner = graphk.Runner(pipeline, session)

runner.start()
runner.run()

print(session.to_dict())

Typical Use Cases

Multi-Handler Processing

Apply all matching route handlers to a single request.

Ordered Fan-Out

Run several transformations in a defined order but still model them as separate branches.

Scenario Composition

Model several optional workflows that should all run when their matchers pass.

BranchPipe vs MultiPipe

Use BranchPipe when:

• one route should win
• routing is exclusive

Use MultiPipe when:

• every matching route should run
• routing is cumulative

Common Mistakes

• Do not use MultiPipe when only one route is supposed to execute.
• Do not assume ORDER_RANDOM is stable unless randomness is explicitly seeded.
• Do not forget that each selected item is still expected to be a pipeline branch.

Learn More

Recommended references:

• tests/multi/
• tests/branch/
• examples/example_9.py