Optimized code and wrote documentation

routes/login.tsx

@@ -1,4 +1,4 @@
-import { Handlers } from "$fresh/server.ts";
+import { FreshContext, Handlers } from "$fresh/server.ts";
 import { State } from "$root/defaults/interfaces.ts";
 import { parse, type RegularTagNode } from "@melvdouc/xml-parser";
 import {
@@ -13,13 +13,23 @@ import { getKey } from "$root/routes/_middleware.ts";
 
 const CAS = "https://ident.univ-amu.fr/cas";
 
-function getTag(tag: CasTagNode): [string, string] {
+/**
+ * Get the tag node value without "cas:" prefix in name.
+ * @param tag The CAS tag node.
+ * @returns The `[name, value]` pair.
+ */
+function getTag(tag: CasTagNode): [name: string, value: string] {
   return [
     tag.tagName.replace("cas:", ""),
     tag.children[0].value,
   ];
 }
 
+/**
+ * Gets the user JWT token with a validity period of one hour.
+ * @param casResponse The CAS reponse parsed from XML.
+ * @returns The user JWT session token.
+ */
 function createUserJWT(casResponse: CasResponse): Promise<string> {
   const nodes = casResponse.children[1].children.map(getTag);
   const fullUserInfos: Record<string, string | string[]> = {};
@@ -28,7 +38,6 @@ function createUserJWT(casResponse: CasResponse): Promise<string> {
     if (typeof fullUserInfos[key] == "string") {
       fullUserInfos[key] = [fullUserInfos[key]];
     }
-
     if (Array.isArray(fullUserInfos[key])) {
       fullUserInfos[key].push(value);
     } else {
@@ -37,12 +46,10 @@ function createUserJWT(casResponse: CasResponse): Promise<string> {
   });
 
   const now = Math.floor(Date.now() / 1000);
-  const oneHour = 60 * 60;
-
   const payload: LoginJWT = {
     iss: "PolyMPR",
     iat: now,
-    exp: now + oneHour,
+    exp: now + 0xe10,
     aud: "PolyMPR",
     user: fullUserInfos as unknown as CasContent,
   };
@@ -51,51 +58,39 @@ function createUserJWT(casResponse: CasResponse): Promise<string> {
   return createJwt(payload, key);
 }
 
-// deno-lint-ignore no-explicit-any
-export const handler: Handlers<any, State> = {
-  async GET(request, context) {
+export const handler: Handlers<null, State> = {
+  /**
+   * Handles all CAS protocol requests.
+   * @param request The incomming HTTP request.
+   * @param context The Fresh context with `State`.
+   * @returns The redirect corresponding to each step of the CAS protocol.
+   */
+  async GET(
+    request: Request,
+    context: FreshContext<State, null>,
+  ): Promise<Response> {
     const url = new URL(request.url);
     const ticket = url.searchParams.get("ticket");
     const service = `${context.url.origin}/login`;
 
-    if (ticket) {
-      const response = await fetch(
-        `${CAS}/serviceValidate?service=${service}&ticket=${ticket}`,
-      );
-      const body = parse(await response.text()) as [RegularTagNode];
-      const casResponse = body[0].children[0] as CasResponse;
-
-      if (casResponse.tagName != "cas:authenticationSuccess") {
-        return new Response(null, {
-          status: 302,
-          headers: {
-            Location: `${CAS}/login?service=${service}`,
-          },
-        });
-      }
-
-      const headers = new Headers();
-
-      setCookie(headers, {
-        name: "sessionToken",
-        value: await createUserJWT(casResponse),
-      });
-      headers.set("Location", "/apps");
-
-      return new Response(null, {
-        status: 302,
-        headers,
-      });
-    }
-
-    if (context.state.isAuthenticated) {
+    if (!ticket) {
       return new Response(null, {
         status: 302,
         headers: {
-          Location: "/apps",
+          Location: context.state.isAuthenticated
+            ? "/apps"
+            : `${CAS}/login?service=${service}`,
         },
       });
-    } else {
+    }
+
+    const response = await fetch(
+      `${CAS}/serviceValidate?service=${service}&ticket=${ticket}`,
+    );
+    const body = parse(await response.text()) as [RegularTagNode];
+    const casResponse = body[0].children[0] as CasResponse;
+
+    if (casResponse.tagName != "cas:authenticationSuccess") {
       return new Response(null, {
         status: 302,
         headers: {
@@ -103,5 +98,18 @@ export const handler: Handlers<any, State> = {
         },
       });
     }
+
+    const headers = new Headers();
+
+    setCookie(headers, {
+      name: "sessionToken",
+      value: await createUserJWT(casResponse),
+    });
+    headers.set("Location", "/apps");
+
+    return new Response(null, {
+      status: 302,
+      headers,
+    });
   },
 };