iOS: Correct way to send a Binary file to an IOT device with no internet connection.

[bcmendis]

Hello all,

I have a piece of code using this library that works perfectly with Android, but am having issues with iOS. It looks like iOS is dropping the connection because the network that my ESP32 creates does not have internet.

If I don't remove the "file://" before wrapping it, I get a ""Failed to create request body error", and if I remove it I get a "The network connection was lost" error.

Not really sure if it's a permissions issue or the way this library expects the filePath.

Has anyone faced this before? Any suggestions would be greatly appreciated.

const sendFirmwareUpdateFile = async ({
  filePath,
  binaryFileName,
// other variables...
}: sendFirmwareUpdateFileProps) => {


  try {
      postUrl = "http://192.168.10.11/update"

    if (filePath) {

      //Checks if file is present
      const getInfo = await FileSystem.getInfoAsync(filePath, {
        size: true,
      });

      if (!getInfo.exists) {
        throw new Error("Firmware file doesn't exist!");
      }

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

////////         Where iOS fails, but Android succeeds

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

      let data;

      if (Platform.OS === "ios") {
        const cleanFilePath = filePath.replace("file://", "");
        data = ReactNativeBlobUtil.wrap(cleanFilePath);
      } else {
        data = ReactNativeBlobUtil.wrap(filePath);
      }

         if (postUrl) {
           const response = await ReactNativeBlobUtil.config({
             trusty: true,             //added for testing, no effect
             wifiOnly: true.         //added for testing, no effect
           }).fetch(
             "POST",
             postUrl,
             {
               "Content-Type": "multipart/form-data",
               networkServiceType: "wifi",            //added for testing, no effect
               allowsCellularAccess: "false",        //added for testing, no effect
             },
             [
               {
                 name: "firmware",
                 filename: binaryFileName,
                 type: "application/octet-stream",
                 data,
               },
             ]
           );


///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

           const rawResponse = (await response.text()) as string;

           if (rawResponse.includes("OK")) {
             console.log("Firmware upload successful: ", rawResponse);
             return true;
             } else { 
                 throw new Error("Firmware could not be uploaded!");
               }

        } else {
          throw new Error("Not a valid POST URL address!");
        }

    } else {
      throw new Error("No valid filepath found!");
    }
  } catch (error) {
    // Error Handling
  }
};

My app.json info.plist has these requests:

"infoPlist": {
        "NSLocalNetworkUsageDescription": "The app requires access to the local network so it can download device updates",
        "NSAllowsLocalNetworking": true,
        "NSAppTransportSecurity": {
          "NSAllowsArbitraryLoads": true,
          "NSExceptionAllowsInsecureHTTPLoads": true
        },
        "UIFileSharingEnabled": true,
        "LSSupportsOpeningDocumentsInPlace": true
      },

[RonRadtke]

Hmm not sure why iOS should require Internet connection.
Do you know if it works if your network has Internet connection?
iOS local connections work in general for me but my network has Internet Access

[bcmendis]

Ideally iOS shouldn't require internet connection, this is my assumption based of the errors and researching them.

I haven't tested over a network with an active internet connection, mostly because it would not work for my use case.

It's not feasible for the ESP to connect to a network with internet, that's why the React Native app connects to the ESP web server and uploads the file.

The app connects to the webserver, but sending the binary file is the issue. I will do more testing and update.

[RonRadtke]

Ideally iOS shouldn't require internet connection, this is my assumption based of the errors and researching them.

I haven't tested over a network with an active internet connection, mostly because it would not work for my use case.

It's not feasible for the ESP to connect to a network with internet, that's why the React Native app connects to the ESP web server and uploads the file.

The app connects to the webserver, but sending the binary file is the issue. I will do more testing and update.

Yes it would just be great to know if it is exclusively a problem due to the non existing internet connection or sth else.
Because I absolutely agree it should work without Internet. There is, in my opinion, no reason for it to require Internet connection