Spec #
This is a top-level attribute of the pipeline spec.
{
"pipeline": {...},
"transform": {...},
"input": {
"union": [
{
"pfs": {
"project": string,
"name": string,
"repo": string,
"branch": string,
"glob": string,
"lazy" bool,
"empty_files": bool,
"s3": bool
}
},
{
"pfs": {
"project": string,
"name": string,
"repo": string,
"branch": string,
"glob": string,
"lazy" bool,
"empty_files": bool,
"s3": bool
}
}
...
]},
...
}
Behavior #
input.union is an array of inputs to combine. The inputs do not have to be
pfs inputs. They can also be union and cross inputs.
Union inputs take the union of other inputs. In the example
below, each input includes individual datums, such as if foo and bar
were in the same repository with the glob pattern set to /*.
Alternatively, each of these datums might have come from separate repositories
with the glob pattern set to / and being the only file system objects in these
repositories.
| inputA | inputB | inputA ∪ inputB |
| ------ | ------ | --------------- |
| foo | fizz | foo |
| bar | buzz | fizz |
| | | bar |
| | | buzz |The union inputs do not take a name and maintain the names of the
sub-inputs. In the example above, you would see files under
/pfs/inputA/... or /pfs/inputB/..., but never both at the same time.
When you write code to address this behavior, make sure that
your code first determines which input directory is present. Starting
with Pachyderm 1.5.3, we recommend that you give your inputs the
same Name. That way your code only needs to handle data being present
in that directory. This only works if your code does not need to be
aware of which of the underlying inputs the data comes from.