Document sample use-cases (#18)

* Add sample usecases of the library to README
* Add outputs to samples
* Correct README

Author: de-sh

README.md

@@ -5,7 +5,7 @@ Currently the library consists of openapi_parser module which helps hydrus parse
 
 To install the library:
 
-```
+```bash
 pip install git+https://github.com/HTTP-APIs/hydra-openapi-parser.git#egg=hydra_openapi_parser
 ```
 
@@ -19,3 +19,58 @@ from hydra_openapi_parser import openapi_parser
 ```
 
 Porting out from hydrus the hydraspecs directory
+
+## Sample use-cases of openapi_parser module
+
+Once the OpenAPI YAML document is assigned into the variable `doc` as a Python dictionary, you can do the following:
+- Parse the OpenAPI doc into a HydraDoc
+```python3
+parsed_dict = openapi_parser.parse(doc)
+```
+- Generate an empty object
+```python3
+object = openapi_parser.generate_empty_object()
+```
+- Test if an endpoint is valid
+```python3
+path = 'A/B/{id}/C/D'
+openapi_parser.valid_endpoint(path)
+# False
+path = 'A/B/{id}'
+openapi_parser.valid_endpoint(path)
+# Collection
+path = 'A/B/C'
+openapi_parser.valid_endpoint(path)
+# True
+```
+- Extract class name from the path
+```python3
+path = "A/B/C/Pet"
+path_list = path.split('/')
+openapi_parser.get_class_name(path_list)
+# Pet
+```
+- Fetch data from location
+```python3
+path = '#/definitions/Order'
+path_list = path.split('/')
+data = openapi_parser.get_data_at_location(path_list, doc)
+# data is of type dict
+```
+- Remove variables from path
+```python3
+path = "A/B/C/{id}"
+output = openapi_parser.sanitise_path(path)
+```
+- Identify if an object is a collection
+```python3
+schema_block = {
+    'type': 'array',
+    'items': {
+        '$ref': '#/definitions/Pet'
+    }
+}
+method = "/Pet"
+openapi_parser.check_collection(schema_block, method)
+# True
+```