Merged in feature/refresh-token (pull request #401)

feat: SW-101 Proactively refresh tokens

Approved-by: Michael Zetterberg

components/Auth/TokenRefresher.tsx

@@ -0,0 +1,65 @@
+"use client"
+import { usePathname, useSearchParams } from "next/navigation"
+import { SessionProvider, useSession } from "next-auth/react"
+import { useEffect, useMemo, useRef } from "react"
+
+import {
+  MAX_KEEP_ALIVE_TIME_IN_MINUTES,
+  PRE_REFRESH_TIME_IN_SECONDS,
+} from "@/constants/auth"
+
+/**
+ * Keeps the access token alive by proactively refreshing it
+ *
+ */
+export default function TokenRefresher() {
+  return (
+    <SessionProvider basePath="/api/web/auth">
+      <Refresher />
+    </SessionProvider>
+  )
+}
+
+function Refresher() {
+  const session = useSession()
+  const pathname = usePathname()
+  const searchParams = useSearchParams()
+  const timeoutId = useRef<NodeJS.Timeout>()
+
+  // Simple inactivity control. Reset when the URL changes.
+  const stopPreRefreshAt = useMemo(
+    () => Date.now() + MAX_KEEP_ALIVE_TIME_IN_MINUTES * 60 * 1000,
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+    [pathname, searchParams]
+  )
+
+  useEffect(() => {
+    if (timeoutId.current) {
+      clearTimeout(timeoutId.current)
+    }
+
+    if (!session.data?.token.expires_at) {
+      return
+    }
+
+    const refreshIn =
+      session.data.token.expires_at -
+      Date.now() -
+      PRE_REFRESH_TIME_IN_SECONDS * 1000
+
+    timeoutId.current = setTimeout(
+      async () => {
+        if (stopPreRefreshAt > Date.now()) {
+          await session.update({ doRefresh: true })
+        }
+      },
+      // If the token has already expired `refreshIn` will be
+      // negative, and we will refresh immediately (in 1 ms)
+      Math.max(refreshIn, 1)
+    )
+
+    return () => clearTimeout(timeoutId.current)
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [session.data?.token.expires_at, stopPreRefreshAt])
+  return null
+}