# Edge
# Edge
Edges represent connections between Tasks.
At a minimum, an edge links an upstream_task
and a downstream_task
indicating that the downstream task shouldn't attempt to run until the upstream task is complete.
In addition, edges can specify a key that describe how upstream results are passed to the downstream task.
Args:
upstream_task (Task)
: the task that must run before thedownstream_task
downstream_task (Task)
: the task that will be run after theupstream_task
. The upstream task state is passed to the downstream task's trigger function to determine whether the downstream task should run.key (str, optional)
: Passing a key indicates that the upstream result should be passed to the downstream task as a keyword argument given bykey
.mapped (bool, optional)
: boolean indicating whether this edge represents a mapped task; defaults toFalse
In general, Edges are created and handled in the background by the Flow class and will not be directly instantiated by users.
Example:
from prefect import *
from prefect.core import Edge
class Add(Task):
def run(self, x):
return x + 1
class Number(Task):
def run(self):
return 2
# passes the result of the Number() task to Add() as 'x'
edge = Edge(Number(), Add(), key='x')
methods: |
---|
prefect.core.edge.Edge.serialize ()[source] |
Represents the Edge as a dict. |
This documentation was auto-generated from commit n/a
on June 17, 2020 at 17:27 UTC