Summary:
With this diff you should now be able to register `example.py` and read
procedures found there. The procedures will be listed through `CALL
mg.procedures() YIELD *` query, but invoking them will raise
`NotYetImplemented`.
If you wish to test this, you will need to run the Memgraph executable
with PYTHONPATH set to the `include` directory where `mgp.py` is found.
Additionally, you need to pass `--query-modules-directory` flag to
Memgraph, such that it points to where it will find the `example.py`.
For example, when running from the root directory of Memgraph repo, the
shell invocation below should do the trick (assuming `./build/memgraph`
is where is the executable). Make sure that `./query_modules/` does not
have `example.so` built, as that may interfere with loading
`example.py`.
PYTHONPATH=$PWD/include ./build/memgraph --query-modules-directory=./query_modules/
Reviewers: mferencevic, ipaljak, llugovic
Reviewed By: mferencevic, ipaljak, llugovic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2678
Summary:
This is the Python 3.5+ version of our C API found in
include/mg_procedure.h. It should strive to be simple to use, but very
hard to misuse. The Python API avoids almost all memory management
issues found in the C API, so it is automatically less error prone.
Unfortunately, we cannot avoid the issue of having some objects being
alive only during the execution of a custom procedure. For such objects
we have a `Invalid<Object>Error` exception types. The Python API should
fairly easily check the validity because all such objects are related to
ProcCtx in some way. Our C/C++ part will push 1 instance of ProcCtx each
time a Python procedure is invoked and can therefore easily change
ProcCtx to be invalid. This can be as simple as changing the
implementation pointer of ProcCtx to NULL.
Reviewers: mferencevic, ipaljak, tlastre, dsantl, buda
Reviewed By: mferencevic, tlastre
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2650
