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CORN
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**System information discovery and asset tracking**
INSTALLATION
============
::
pip install corn
INSTALLATION FOR DEVELOPMENT
============================
Clone the `corn` repo and install with pip::
git clone https://gitlab.com/saltstack/pop/corn.git
pip install -e corn
EXECUTION
=========
After installation the `corn` command should now be available.
The command will have no output until it is vertically extended (details below).
TESTING
=======
install `requirements-test.txt` with pip and run pytest::
pip install -r corn/requirements-test.txt
pytest corn/tests
VERTICAL APP-MERGING
====================
Instructions for extending corn
Install pop::
pip install --upgrade pop
Create a new directory for the project::
mkdir corn_{project_name}
cd corn_{project_name}
Use `pop-seed` to generate the structure of a project that extends `corn`:
pop-seed -t v corn_{project_name} -d corn
* "-t v" specifies that this is a vertically app-merged project
* "-d corn" says that we want to implement the dynamic name of "corn"
Notice that some structure has been created for you.
We especially care about the new directory in `corn_{project_name}/corn`
Add "corn" to the requirements.txt::
echo "corn" >> requirements.txt
CREATING CORNS
==============
- Create a new file in "corn_{project_name}/corn"
- The directory should already have been created by `pop-seed`.
- The file name is arbitrary.
- Every file in this directory, then it's subdirectories, will be parsed "simultaneously" (as far as that makes sense for asyncio).
- Corns that are dependant on each other should be assigned in the same function.
- Do NOT rely on the collector's recursion strategy for corns to depend on each other.
- Use `hub.corn.init.wait_for("corn")` to wait for corns to be generated by another sub
- Add your new project to the python path
- alternatively, run "pip install -e ." from your project's root directory
- you only need to do this once
- Create an async function in this file with a descriptive yet arbitrary name
- By convention it should start with "load"
- Make it async unless you have a really really really good reason.
- Grains that depend on each other already belong in the same function, don't depend on synchronous programming for determinism
- Corns can be accessed and assigned like a dictionary, but our convention is to use the namespace
Example::
async def load_my_corn(hub):
hub.corn.CORN.new_corn = "Hello World!"
And that's it! Now verify that your corn is collected from the command line::
corn new_corn
Output::
new_corn:
Hello World!
