管道在 kedro 中找不到节点

Question

我正在学习管道教程，创建所有需要的文件，用kedro run --node=preprocessing_data启动kedro，但遇到了这样的错误消息：

ValueError: Pipeline does not contain nodes named ['preprocessing_data'].

如果我在没有node参数的情况下运行kedro，我会收到

kedro.context.context.KedroContextError: Pipeline contains no nodes

文件内容：

src/project/pipelines/data_engineering/nodes.py
def preprocess_data(data: SparkDataSet) -> None:
print(data)
return

src/project/pipelines/data_engineering/pipeline.py
def create_pipeline(**kwargs):
return Pipeline(
[
node(
func=preprocess_data,
inputs="data",
outputs="preprocessed_data",
name="preprocessing_data",
),
]
)

src/project/pipeline.py
def create_pipelines(**kwargs) -> Dict[str, Pipeline]:
de_pipeline = de.create_pipeline()
return {
"de": de_pipeline,
"__default__": Pipeline([])
}

Answer 1

我认为您需要在__default__中拥有管道。例如

def create_pipelines(**kwargs) -> Dict[str, Pipeline]:
de_pipeline = de.create_pipeline()
return {
"de": data_engineering_pipeline,
"__default__": data_engineering_pipeline
}

那么kedro run --node=preprocessing_data对我有效。

Answer 2

Mayurc是正确的，因为__default__管道是空的，所以没有节点。另一个选项是使用cli仅运行de管道。

kedro run --pipeline de

您可以在run命令的帮助文本中找到此选项及更多内容。

$ kedro run --help
Usage: kedro run [OPTIONS]
Run the pipeline.
Options:
--from-inputs TEXT        A list of dataset names which should be used as a
starting point.
--from-nodes TEXT         A list of node names which should be used as a
starting point.
--to-nodes TEXT           A list of node names which should be used as an
end point.
-n, --node TEXT           Run only nodes with specified names.
-r, --runner TEXT         Specify a runner that you want to run the pipeline
with.
This option cannot be used together with
--parallel.
-p, --parallel            Run the pipeline using the `ParallelRunner`.
If
not specified, use the `SequentialRunner`. This
flag cannot be used together
with --runner.
-e, --env TEXT            Run the pipeline in a configured environment. If
not specified,
pipeline will run using environment
`local`.
-t, --tag TEXT            Construct the pipeline using only nodes which have
this tag
attached. Option can be used multiple
times, what results in a
pipeline constructed from
nodes having any of those tags.
-lv, --load-version TEXT  Specify a particular dataset version (timestamp)
for loading.
--pipeline TEXT           Name of the modular pipeline to run.
If not set,
the project pipeline is run by default.
-c, --config FILE         Specify a YAML configuration file to load the run
command arguments from. If command line arguments
are provided, they will
override the loaded ones.
--params TEXT             Specify extra parameters that you want to pass
to
the context initializer. Items must be separated
by comma, keys - by colon,
example:
param1:value1,param2:value2. Each parameter is
split by the first comma,
so parameter values are
allowed to contain colons, parameter keys are not.
-h, --help                Show this message and exit.

发布了第二个答案，因为完整的帮助输出不适合评论。