Add simple example

Author: pgleeson

examples/document.json

@@ -0,0 +1,9 @@
+{
+    "MyBook": {
+        "title": "My life in Python",
+        "pages": {
+            "1": {},
+            "2": {}
+        }
+    }
+}

examples/document.py

@@ -0,0 +1,72 @@
+from modelspec import *
+from modelspec.utils import *
+
+# Example showing how to create a model of a document and use it to create/serialise instances
+
+
+class Document(BaseWithId):
+
+    _definition = "A model for documents"
+
+    def __init__(self, **kwargs):
+
+        self.allowed_children = collections.OrderedDict(
+            [
+                ("pages", ("The pages", Page)),
+            ]
+        )
+
+        self.allowed_fields = collections.OrderedDict(
+            [
+                ("title", ("Document title", str)),
+                (
+                    "ISBN",
+                    (
+                        "International Standard Book Number",
+                        int,
+                    ),
+                ),
+            ]
+        )
+
+        super(Document, self).__init__(**kwargs)
+
+
+class Page(BaseWithId):
+
+    _definition = "A model of a page"
+
+    def __init__(self, **kwargs):
+
+        self.allowed_children = collections.OrderedDict(
+            [
+                ("lines", ("The pages", Line)),
+            ]
+        )
+
+        super(Page, self).__init__(**kwargs)
+
+
+class Line(Base):
+
+    _definition = "A model of a line"
+
+    def __init__(self, **kwargs):
+
+        self.allowed_fields = collections.OrderedDict(
+            [
+                ("title", ("Document title", str)),
+            ]
+        )
+
+
+doc = Document(id="MyBook")
+doc.title = "My life in Python"
+
+doc.pages.append(Page(id=1))
+doc.pages.append(Page(id=2))
+
+print(doc)
+
+doc.to_json_file("document.json")
+doc.to_yaml_file("document.yaml")

examples/document.yaml

@@ -0,0 +1,5 @@
+MyBook:
+    title: My life in Python
+    pages:
+        '1': {}
+        '2': {}

test_all.sh

@@ -3,5 +3,10 @@ set -ex
 
 pip install .
 
+cd examples
+python document.py
+
+cd ..
+
 cd modelspec/test
 pytest -v