Add example to readme

README.md

@@ -1,2 +1,67 @@
 # schemars
 Generate JSON Schema documents from Rust code
+
+Work in progress!
+
+## Basic Usage
+
+```rust
+use schemars::{JsonSchema, schema_for};
+use serde::{Deserialize, Serialize};
+
+#[derive(Deserialize, Serialize, JsonSchema)]
+#[serde(rename_all = "camelCase")]
+struct MyStruct {
+    my_int: i32,
+    my_nullable: Option<bool>,
+    #[serde(default)]
+    my_string: String,
+    #[serde(rename = "myArray")]
+    my_float_vec: Vec<f32>,
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let schema = schema_for!(MyStruct)?;
+    println!("{}", serde_json::to_string_pretty(&schema)?);
+    Ok(())
+}
+```
+
+This outputs the following:
+
+```json
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "MyStruct",
+  "type": "object",
+  "required": [
+    "myArray",
+    "myInt",
+    "myNullable"
+  ],
+  "properties": {
+    "myArray": {
+      "type": "array",
+      "items": {
+        "type": "number",
+        "format": "float"
+      }
+    },
+    "myInt": {
+      "type": "integer",
+      "format": "int32"
+    },
+    "myNullable": {
+      "type": [
+        "boolean",
+        "null"
+      ]
+    },
+    "myString": {
+      "type": "string"
+    }
+  }
+}
+```
+
+Note that the `#[serde(...)]` attributes are respected.