Merge pull request #2 from lestex/update-readme

updates readme with usage

Author: lestex

README.md

@@ -1,2 +1,105 @@
-# py-githubactions
-Github actions core library implemented in python.
+# pygithubactions
+### pygithubactions/core
+> Core functions for setting results, logging, registering secrets and exporting variables across actions
+
+### Usage
+
+### Import the package
+
+```python
+import pygithubaction.core
+```
+
+### Inputs/Outputs
+
+Action inputs can be read with `get_input` which returns a `str` or `get_boolean_input` which parses a boolean based on the [yaml 1.2 specification](https://yaml.org/spec/1.2/spec.html#id2804923). If `required` set to be false, the input should have a default value in `action.yml`.
+
+Outputs can be set with `set_output` which makes them available to be mapped into inputs of other actions to ensure they are decoupled.
+
+```python
+from pygithubaction.core import get_input
+from pygithubaction.core import set_output
+
+my_input = get_input('inputName', required=True);
+boolean_input = get_boolean_input('booleanInputName', required=True);
+multiline_input = get_multiline_input('multilineInputName', required=True)
+
+set_output('outputkey', 'outputval')
+```
+
+### Exporting variables
+
+Since each step runs in a separate process, you can use `export_variable` to add it to this step and future steps environment blocks.
+
+```python
+from pygithubaction.core import export_variable
+
+export_variable('envvar', 'val')
+```
+
+### Setting a secret
+
+Setting a secret registers the secret with the runner to ensure it is masked in logs.
+
+```python
+from pygithubaction.core import set_secret
+
+set_secret('mypassword')
+```
+
+### PATH Manipulation
+
+To make a tool's path available in the path for the remainder of the job (without altering the machine or containers state), use `add_path`.  The runner will prepend the path given to the jobs PATH.
+
+```python
+from pygithubaction.core import add_path
+
+add_path('/path/to/mytool')
+```
+
+### Exit codes
+
+You should use this library to set the failing exit code for your action.  If status is not set and the script runs to completion, that will lead to a success.
+
+```python
+from pygithubaction.core import set_failed
+
+try:
+    # Do stuff
+    # ...
+
+except Exception as e:
+    # set_failed logs the message and sets a failing exit code
+    set_failed(f'Action failed with error {e}')
+```
+
+### Logging
+
+Finally, this library provides some utilities for logging. Note that debug logging is hidden from the logs by default. This behavior can be toggled by enabling the [Step Debug Logs](../../docs/action-debugging.md#step-debug-logs).
+
+```python
+from pygithubaction.core import (
+    get_input, debug, info, notice, is_debug, error
+)
+
+
+my_input = get_input('input');
+
+try:
+    debug('Inside try block')
+  
+    if not my_input:
+        warning('my_input was not set')
+  
+    if is_debug():
+        # curl -v https://github.com
+    else:
+        # curl https://github.com
+
+    # Do stuff
+    info('Output to the actions build log')
+    notice('This is a message that will also emit an annotation')
+
+except Exception as e:
+    error(f'Error: {e}, action may still succeed though')
+```