Duncan Tourolle
298c9e770b
Neither Python example was registered as a test, so `ctest -L examples` in CI skipped them entirely -- which is how 08's missing Python node went unnoticed. Add a kpn_python_example() helper (gated on KPN_BUILD_PYTHON) that runs each script with PYTHONPATH pointed at the freshly-built module, so it does not depend on cwd or a hard-coded build/python path, and register 07 and 08. Also del the network in 07 for deterministic teardown.
38 lines
952 B
Python
38 lines
952 B
Python
"""
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07_python_network — hello pipeline with a Python node in the middle.
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Graph:
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[ProduceNode] --int--> [py_double] --int--> [PrintItNode]
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ProduceNode and PrintItNode are C++ nodes wrapped in VariantNodeWrapper.
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py_double is a pure Python callable — doubles its input using Python arithmetic.
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"""
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import sys
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import time
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sys.path.insert(0, "build/python")
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import kpn_python as kpn
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def py_double(x: int) -> int:
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return x * 2
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net = kpn.Network()
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net.add("src", kpn.make_produce())
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net.add_node("dbl", py_double, inputs=["int"], outputs=["int"])
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net.add("sink", kpn.make_print_it())
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net.connect("src", 0, "dbl", 0)
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net.connect("dbl", 0, "sink", 0)
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net.build()
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net.start()
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time.sleep(0.1)
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net.stop()
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# Drop the network deterministically: it holds the Python callable, which forms
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# a reference cycle via globals(). Deleting the global breaks it so the network
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# is reclaimed now rather than lingering to interpreter shutdown.
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del net
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