Add automatic refresh of authentication tokens

src/date_ffi.mjs

@@ -17,6 +17,10 @@ export function to_iso8601(date) {
   return date.toISOString();
 }
 
+export function to_unix(date) {
+  return date.getTime();
+}
+
 export function unix_now() {
   return Date.now();
 }

src/geo_t/config.gleam

@@ -12,6 +12,7 @@ pub type Config {
     debug: Bool,
     api_timeout: Int,
     api_auth_url: Uri,
+    api_auth_token_refresh_diff: Int,
     api_installations_url: Uri,
     api_device_url: Uri,
     api_device_status_url: Uri,
@@ -38,6 +39,10 @@ pub fn load_config() -> Config {
       config_helpers.api_auth_url,
       "https://thermia-auth-api.azurewebsites.net/api/v1/Jwt/login",
     ),
+    api_auth_token_refresh_diff: get_env(
+      config_helpers.api_auth_token_refresh_diff,
+      300_000,
+    ),
     api_installations_url: get_uri(
       config_helpers.api_installations_url,
       "https://online-genesis-serviceapi.azurewebsites.net/api/v1/installationsInfo",

src/geo_t/helpers/config.gleam

@@ -16,6 +16,10 @@ pub fn api_auth_url() {
   config_url("api_auth_url")
 }
 
+pub fn api_auth_token_refresh_diff() {
+  config("api_auth_token_refresh_diff", dynamic.int)
+}
+
 pub fn api_installations_url() {
   config_url("api_installations_url")
 }

src/geo_t/helpers/date.gleam

@@ -13,6 +13,9 @@ pub fn to_iso8601(d: Date) -> String
 @external(javascript, "../../date_ffi.mjs", "from_unix")
 pub fn from_unix(a: Int) -> Result(Date, Nil)
 
+@external(javascript, "../../date_ffi.mjs", "to_unix")
+pub fn to_unix(a: Date) -> Int
+
 @external(javascript, "../../date_ffi.mjs", "now")
 pub fn now() -> Date
 

src/geo_t/web.gleam

@@ -1,11 +1,15 @@
 import gleam/option.{None, Option, Some}
+import gleam/order
 import gleam/string
+import gleam/io
 import gleam/javascript/promise
 import lustre
 import lustre/element/html
 import lustre/effect.{Effect}
 import lustre/element
 import plinth/javascript/storage.{Storage}
+import geo_t/helpers/timers
+import geo_t/helpers/date
 import geo_t/config.{Config}
 import geo_t/web/login_view
 import geo_t/web/installations_view
@@ -15,6 +19,8 @@ import geo_t/pump_api/api.{ApiError}
 import geo_t/pump_api/auth/api as auth_api
 import geo_t/web/auth.{AuthInfo, AuthInfoStorage}
 
+const auth_update_check_interval = 10_000
+
 pub fn main() {
   let app = lustre.application(init, update, view)
   let assert Ok(_) = lustre.start(app, "[data-lustre-app]", Nil)
@@ -41,6 +47,8 @@ pub type Msg {
   LoginResult(Result(User, ApiError))
   InstallationsView(installations_view.Msg)
   PumpView(pump_view.Msg)
+  AuthRefreshCheck
+  RefreshLogin
 }
 
 fn init(_) {
@@ -52,6 +60,9 @@ fn init(_) {
     Error(_) -> None
   }
 
+  let auth_refresh_effect =
+    effect.from(fn(dispatch) { auth_refresh_check_timer(dispatch) })
+
   let #(inst_model, inst_effect) = case auth_info {
     Some(info) ->
       update_installations(
@@ -73,13 +84,15 @@ fn init(_) {
       logging_in: False,
       logged_in: option.is_some(auth_info),
     ),
-    inst_effect,
+    effect.batch([auth_refresh_effect, inst_effect]),
   )
 }
 
 fn update(model: Model, msg: Msg) {
   case msg {
-    LoginView(login_view.AttemptLogin) -> {
+    AuthRefreshCheck -> #(model, auth_refresh_check(model))
+
+    RefreshLogin | LoginView(login_view.AttemptLogin) -> {
       #(
         Model(
           ..model,
@@ -164,11 +177,11 @@ fn view(model: Model) {
   html.div(
     [],
     [
-      case model.logged_in {
+      case model.auth {
-        False ->
+        None ->
           login_view.view(model.login)
           |> element.map(LoginView)
-        True -> {
+        Some(_) -> {
           case model.pump {
             None ->
               installations_view.view(model.installations)
@@ -183,6 +196,46 @@ fn view(model: Model) {
   )
 }
 
+fn auth_refresh_check_timer(dispatch) {
+  timers.set_timeout(
+    fn() { dispatch(AuthRefreshCheck) },
+    auth_update_check_interval,
+  )
+
+  Nil
+}
+
+fn auth_refresh_check(model: Model) {
+  use dispatch <- effect.from()
+
+  auth_refresh_check_timer(dispatch)
+
+  case model.auth {
+    Some(auth) -> {
+      let now = date.now()
+      let assert Ok(last_valid_time) =
+        date.from_unix(
+          date.to_unix(auth.user.tokens.access_token_expiry) - model.config.api_auth_token_refresh_diff,
+        )
+
+      case date.compare(now, last_valid_time) {
+        order.Gt -> {
+          io.println("[AuthCheck] Auth expiring soon, refreshing...")
+          dispatch(RefreshLogin)
+          Nil
+        }
+
+        order.Lt | order.Eq -> {
+          io.println("[AuthCheck] Auth not expiring yet, no need to refresh.")
+        }
+      }
+
+      Nil
+    }
+    None -> Nil
+  }
+}
+
 fn login(model: Model) -> Effect(Msg) {
   use dispatch <- effect.from()