Access stdout of Conducto Exec node - jenkins

Question

Is there an example I can see of accessing the stdout of an Exec node? I am trying to parse stdout similarly to Jenkins groovy dsl:
tobeparsed = sh(returnStdout: true, script: "myscript.sh")

Answer 1

That feature is not available in Conducto. When you want to send data from one node to another, there are a few ways to do so.
In these examples let's try to generate a random number in the first node, and have the second echo it.
A simple option is to use co.data to save the data in the first node, then get it from the second node.
import conducto as co
import random
img = co.Image(copy_dir=".")
def first():
# Generate a random number and save it to co.data,
# scoped to the current pipeline.
number = random.random()
co.data.pipeline.puts("random_number", str(number).encode())
print(f"Saved random number to co.data. Value: {number}")
def second():
# Read the value from co.data
stored = co.data.pipeline.gets("random_number")
number = float(stored.decode())
print(f"Read random number from co.data. Value: {number}")
def main() -> co.Serial:
with co.Serial(image=img) as output:
output["first"] = co.Exec("python pipeline.py first")
output["second"] = co.Exec("python pipeline.py second")
return output
if __name__ == '__main__':
co.main(default=main)
A more sophisticated way: the first node could be called from a co.Lazy, and generate the second node once it knows the value.
import conducto as co
import random
img = co.Image(copy_dir=".")
def first() -> co.Serial:
output = co.Serial()
# Generate a random number and encode it into command
# of second node
output["second"] = co.Exec(f"echo {random.random}")
return output
def main() -> co.Serial:
return co.Lazy("python pipeline.py first", image=img)
if __name__ == '__main__':
co.main(default=main)
In either case, save that text to a file called pipeline.py. Run it with python pipeline.py to see the tree it would generate. Run python pipeline.py --local to run it on your machine.
There's nothing magical about the name pipeline.py, just make sure it matches the commands in the co.Exec nodes.