1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152

use super::{
	builder::OpenapiBuilder,
	handler::{OpenapiDocHandler, OpenapiSpecHandler},
	operation::OperationDescription
};
use crate::{routing::*, EndpointWithSchema, ResourceWithSchema, ResponseSchema};
use gotham::{
	hyper::{Method, StatusCode},
	pipeline::PipelineHandleChain,
	prelude::*,
	router::builder::{RouterBuilder, ScopeBuilder}
};
use lazy_regex::regex_replace_all;
use openapi_type::OpenapiType;
use std::{collections::HashMap, panic::RefUnwindSafe};

/// This trait adds the `openapi_spec` and `openapi_doc` method to an OpenAPI-aware router.
pub trait GetOpenapi {
	/// Register a GET route to `path` that returns the OpenAPI specification in JSON format.
	fn openapi_spec(&mut self, path: &str);

	/// Register a GET route to `path` that returns the OpenAPI documentation in HTML format.
	fn openapi_doc(&mut self, path: &str);
}

#[derive(Debug)]
pub struct OpenapiRouter<'a, D> {
	pub(crate) router: &'a mut D,
	pub(crate) scope: Option<&'a str>,
	pub(crate) openapi_builder: &'a mut OpenapiBuilder
}

macro_rules! implOpenapiRouter {
	($implType:ident) => {
		impl<'a, 'b, C, P> OpenapiRouter<'a, $implType<'b, C, P>>
		where
			C: PipelineHandleChain<P> + Copy + Send + Sync + 'static,
			P: RefUnwindSafe + Send + Sync + 'static
		{
			pub fn scope<F>(&mut self, path: &str, callback: F)
			where
				F: FnOnce(&mut OpenapiRouter<'_, ScopeBuilder<'_, C, P>>)
			{
				let mut openapi_builder = self.openapi_builder.clone();
				let new_scope = self
					.scope
					.map(|scope| format!("{scope}/{path}").replace("//", "/"));
				self.router.scope(path, |router| {
					let mut router = OpenapiRouter {
						router,
						scope: Some(new_scope.as_ref().map(String::as_ref).unwrap_or(path)),
						openapi_builder: &mut openapi_builder
					};
					callback(&mut router);
				});
			}
		}

		impl<'a, 'b, C, P> GetOpenapi for OpenapiRouter<'a, $implType<'b, C, P>>
		where
			C: PipelineHandleChain<P> + Copy + Send + Sync + 'static,
			P: RefUnwindSafe + Send + Sync + 'static
		{
			fn openapi_spec(&mut self, path: &str) {
				self.router
					.get(path)
					.to_new_handler(OpenapiSpecHandler::new(
						self.openapi_builder.openapi.clone()
					));
			}

			fn openapi_doc(&mut self, path: &str) {
				self.router
					.get(path)
					.to_new_handler(OpenapiDocHandler::new(self.openapi_builder.openapi.clone()));
			}
		}

		impl<'a, 'b, C, P> DrawResourcesWithSchema for OpenapiRouter<'a, $implType<'b, C, P>>
		where
			C: PipelineHandleChain<P> + Copy + Send + Sync + 'static,
			P: RefUnwindSafe + Send + Sync + 'static
		{
			fn resource<R: ResourceWithSchema>(&mut self, mut path: &str) {
				if path.starts_with('/') {
					path = &path[1..];
				}
				R::setup((self, path));
			}
		}

		impl<'a, 'b, C, P> DrawResourceRoutesWithSchema
			for (&mut OpenapiRouter<'a, $implType<'b, C, P>>, &str)
		where
			C: PipelineHandleChain<P> + Copy + Send + Sync + 'static,
			P: RefUnwindSafe + Send + Sync + 'static
		{
			fn endpoint<E: EndpointWithSchema + 'static>(&mut self) {
				let mut responses: HashMap<StatusCode, _> = HashMap::new();
				for code in E::Output::status_codes() {
					responses.insert(
						code,
						(self.0).openapi_builder.add_schema(E::Output::schema(code))
					);
				}
				let mut path = format!("{}/{}", self.0.scope.unwrap_or_default(), self.1);
				let mut descr = OperationDescription::new::<E>(responses, &path);
				if E::has_placeholders() {
					descr.set_path_params(E::Placeholders::schema());
				}
				if E::needs_params() {
					descr.set_query_params(E::Params::schema());
				}
				if E::needs_body() {
					let body_schema = (self.0).openapi_builder.add_schema(E::Body::schema());
					descr.set_body::<E::Body>(body_schema);
				}

				let uri: &str = &E::uri();
				let uri =
					regex_replace_all!(r#"(^|/):([^/]+)(/|$)"#, uri, |_, prefix, name, suffix| {
						format!("{prefix}{{{name}}}{suffix}")
					});
				if !uri.is_empty() {
					path = format!("{path}/{uri}");
				}

				let op = descr.into_operation();
				let mut item = (self.0).openapi_builder.remove_path(&path);
				match E::http_method() {
					Method::GET => item.get = Some(op),
					Method::PUT => item.put = Some(op),
					Method::POST => item.post = Some(op),
					Method::DELETE => item.delete = Some(op),
					Method::OPTIONS => item.options = Some(op),
					Method::HEAD => item.head = Some(op),
					Method::PATCH => item.patch = Some(op),
					Method::TRACE => item.trace = Some(op),
					method => {
						warn!("Ignoring unsupported method '{method}' in OpenAPI Specification")
					}
				};
				(self.0).openapi_builder.add_path(path, item);

				(&mut *(self.0).router, self.1).endpoint::<E>()
			}
		}
	};
}

implOpenapiRouter!(RouterBuilder);
implOpenapiRouter!(ScopeBuilder);