loading external MIME sniffing library moved to executeConfig() (ref. #48)

service-worker.js

@@ -381,6 +381,26 @@ let executeConfig = (pluginsConfig) => {
         
     }
     
+    // finally -- do we want to use MIME type guessing based on content?
+    // dealing with this at the very end so that we know we can safely set detectMimeFromBuffer
+    // and not need to re-set it back in case anything fails
+    if (self.LibResilientConfig.useMimeSniffingLibrary === true) {
+        // we do not want to hit a NetworkError and end up using the default config
+        // much better to end up not using the fancy MIME type detection in such a case
+        try {
+            // we do! load the external lib
+            self.importScripts(`./lib/file-type.js`)
+        } catch (e) {
+            self.log('service-worker', `error when fetching external MIME sniffing library: ${e.message}`)
+        }
+        if (typeof fileType !== 'undefined' && "fileTypeFromBuffer" in fileType) {
+            detectMimeFromBuffer = fileType.fileTypeFromBuffer
+            self.log('service-worker', 'loaded external MIME sniffing library')
+        } else {
+            self.log('service-worker', 'failed to load external MIME sniffing library!')
+        }
+    }
+    
 }
 
 
@@ -447,24 +467,6 @@ let initServiceWorker = async () => {
             self.log('service-worker', 'config loading failed, using defaults; error:', e)
         }
         
-        // first let's deal with the easy part -- do we want to use MIME type guessing based on content?
-        if (self.LibResilientConfig.useMimeSniffingLibrary === true) {
-            // we do not want to hit a NetworkError and end up using the default config
-            // much better to end up not using the fancy MIME type detection in such a case
-            try {
-                // we do! load the external lib
-                self.importScripts(`./lib/file-type.js`)
-            } catch (e) {
-                self.log('service-worker', `error when fetching external MIME sniffing library: ${e.message}`)
-            }
-            if (typeof fileType !== 'undefined' && "fileTypeFromBuffer" in fileType) {
-                detectMimeFromBuffer = fileType.fileTypeFromBuffer
-                self.log('service-worker', 'loaded external MIME sniffing library')
-            } else {
-                self.log('service-worker', 'failed to load external MIME sniffing library!')
-            }
-        }
-        
         // create the LibResilientPluginConstructors map
         // the global... hack is here so that we can run tests; not the most elegant
         // TODO: find a better way