add example doc

jsonschema/example_test.go

@@ -0,0 +1,42 @@
+package jsonschema_test
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/cloudquery/codegen/jsonschema"
+)
+
+func Example_basicSchema() {
+	type basic struct {
+		A string `json:"a" jsonschema:"minLength=2,required"`
+	}
+
+	data, err := jsonschema.Generate(new(basic))
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println(string(data))
+	// Output:
+	// {
+	//   "$schema": "https://json-schema.org/draft/2020-12/schema",
+	//   "$id": "https://github.com/cloudquery/codegen/jsonschema_test/basic",
+	//   "$ref": "#/$defs/basic",
+	//   "$defs": {
+	//     "basic": {
+	//       "properties": {
+	//         "a": {
+	//           "type": "string",
+	//           "minLength": 2
+	//         }
+	//       },
+	//       "additionalProperties": false,
+	//       "type": "object",
+	//       "required": [
+	//         "a"
+	//       ]
+	//     }
+	//   }
+	// }
+}

jsonschema/jsonschema.go

@@ -7,6 +7,7 @@ import (
 	"github.com/invopop/jsonschema"
 )
 
+// Generate returns a formatted JSON schema for the parameter.
 func Generate(a any) ([]byte, error) {
 	sc := (&jsonschema.Reflector{RequiredFromJSONSchemaTags: true}).ReflectFromType(reflect.TypeOf(a))
 	return json.MarshalIndent(sc, "", "  ")