Adds new setting to control whether HTTPs is "strict" or not

- "non strict" allows use of self-signed server certificates for example

lib/api.dart

@@ -6,6 +6,7 @@ import "package:flutter/foundation.dart";
 import "package:http/http.dart" as http;
 import "package:intl/intl.dart";
 import "package:inventree/app_colors.dart";
+import "package:inventree/app_settings.dart";
 
 import "package:open_file/open_file.dart";
 import "package:cached_network_image/cached_network_image.dart";
@@ -82,7 +83,7 @@ class APIResponse {
 /*
  * Custom FileService for caching network images
  * Requires a custom badCertificateCallback,
- * so we can accept "dodgy" certificates
+ * so we can accept "dodgy" (e.g. self-signed) certificates
  */
 class InvenTreeFileService extends FileService {
 
@@ -142,6 +143,8 @@ class InvenTreeAPI {
   // Minimum required API version for server
   static const _minApiVersion = 7;
 
+  bool _strictHttps = false;
+
   // Endpoint for requesting an API token
   static const _URL_GET_TOKEN = "user/token/";
 
@@ -308,6 +311,9 @@ class InvenTreeAPI {
     username = username.trim();
     password = password.trim();
 
+    // Cache the "strictHttps" setting, so we can use it later without async requirement
+    _strictHttps = await InvenTreeSettingsManager().getValue(INV_STRICT_HTTPS, false) as bool;
+
     if (address.isEmpty || username.isEmpty || password.isEmpty) {
       showSnackIcon(
         L10().incompleteDetails,
@@ -620,7 +626,9 @@ class InvenTreeAPI {
 
     HttpClientRequest? _request;
 
-    var client = createClient(allowBadCert: true);
+    final bool strictHttps = await InvenTreeSettingsManager().getValue(INV_STRICT_HTTPS, false) as bool;
+
+    var client = createClient(strictHttps: strictHttps);
 
     // Attempt to open a connection to the server
     try {
@@ -811,22 +819,22 @@ class InvenTreeAPI {
     );
   }
 
-  HttpClient createClient({bool allowBadCert = true}) {
+  HttpClient createClient({bool strictHttps = false}) {
 
     var client = HttpClient();
 
     client.badCertificateCallback = (X509Certificate cert, String host, int port) {
-      // TODO - Introspection of actual certificate?
 
-      if (allowBadCert) {
-        return true;
-      } else {
+      if (strictHttps) {
         showServerError(
           L10().serverCertificateError,
           L10().serverCertificateInvalid,
         );
         return false;
       }
+
+      // Strict HTTPs not enforced, so we'll ignore the bad cert
+      return true;
     };
 
     // Set the connection timeout
@@ -874,7 +882,9 @@ class InvenTreeAPI {
 
     HttpClientRequest? _request;
 
-    var client = createClient(allowBadCert: true);
+    final bool strictHttps = await InvenTreeSettingsManager().getValue(INV_STRICT_HTTPS, false) as bool;
+
+    var client = createClient(strictHttps: strictHttps);
 
     // Attempt to open a connection to the server
     try {
@@ -1113,7 +1123,9 @@ class InvenTreeAPI {
     CacheManager manager = CacheManager(
       Config(
         key,
-        fileService: InvenTreeFileService(),
+        fileService: InvenTreeFileService(
+          strictHttps: _strictHttps,
+        ),
       )
     );
 

lib/app_settings.dart

@@ -22,6 +22,8 @@ const String INV_STOCK_SHOW_HISTORY = "stockShowHistory";
 
 const String INV_REPORT_ERRORS = "reportErrors";
 
+const String INV_STRICT_HTTPS = "strictHttps";
+
 class InvenTreeSettingsManager {
 
   factory InvenTreeSettingsManager() {

lib/settings/app_settings.dart

@@ -29,6 +29,7 @@ class _InvenTreeAppSettingsState extends State<InvenTreeAppSettingsWidget> {
   bool stockShowHistory = false;
 
   bool reportErrors = true;
+  bool strictHttps = false;
 
   @override
   void initState() {
@@ -50,6 +51,7 @@ class _InvenTreeAppSettingsState extends State<InvenTreeAppSettingsWidget> {
     stockShowHistory = await InvenTreeSettingsManager().getValue(INV_STOCK_SHOW_HISTORY, false) as bool;
 
     reportErrors = await InvenTreeSettingsManager().getValue(INV_REPORT_ERRORS, true) as bool;
+    strictHttps = await InvenTreeSettingsManager().getValue(INV_STRICT_HTTPS, false) as bool;
 
     setState(() {
     });
@@ -163,15 +165,29 @@ class _InvenTreeAppSettingsState extends State<InvenTreeAppSettingsWidget> {
             Divider(height: 1),
             ListTile(
               title: Text(
-                L10().errorReporting,
+                L10().appSettings,
                 style: TextStyle(fontWeight: FontWeight.bold),
               ),
-              leading: FaIcon(FontAwesomeIcons.bug),
+              leading: FaIcon(FontAwesomeIcons.mobile),
+            ),
+            ListTile(
+              title: Text(L10().strictHttps),
+              subtitle: Text(L10().strictHttpsDetails),
+              leading: FaIcon(FontAwesomeIcons.lock),
+              trailing: Switch(
+                value: strictHttps,
+                onChanged: (bool value) {
+                  InvenTreeSettingsManager().setValue(INV_STRICT_HTTPS, value);
+                  setState(() {
+                    strictHttps = value;
+                  });
+                },
+              ),
             ),
             ListTile(
               title: Text(L10().errorReportUpload),
               subtitle: Text(L10().errorReportUploadDetails),
-              leading: FaIcon(FontAwesomeIcons.cloudUploadAlt),
+              leading: FaIcon(FontAwesomeIcons.bug),
               trailing: Switch(
                 value: reportErrors,
                 onChanged: (bool value) {