GDCWebserver serverURL is null when wifi is turned off

Question

I am not accessing from a different network. I am just trying to serve files for a hybrid app.

Just running the basic server works as intended when I am connected to a wifi network using the code below:

  let webServer = GCDWebServer()

    webServer.addDefaultHandlerForMethod("GET", requestClass: GCDWebServerRequest.self, processBlock: {request in
        return GCDWebServerDataResponse(HTML:"<html><body><p>Hello World</p></body></html>")

    })

    webServer.startWithPort(8080, bonjourName: "GCD Web Server")

    print("Visit \(webServer.serverURL) in your web browser")

logs:

Visit http://192.168.1.132:8080/ in your web browser

When I drop wifi and start the app and server I get:

GCDWebServer started on port 8080 and reachable at (null)

Does your device have a 3G/4G connection? If not, then when WiFi is off it has no active interfaces. In theory, the loopback interface should still be active, but GCDWebServer doesn't seem to have an option to allow you to specify an interface — Paulw11, Jul 15 '16 at 01:24
Suggest you rename title of post to use GCDWebServer for better exposure for this Q/A — DwarDoh, Aug 23 '17 at 20:08

Omer Faruk Ozturk · Answer 1 · 2020-06-29T11:55:24.353

Try starting the server binding to localhost regardless of connection type (wifi or 3g/4g)

do {
    try webServer.start(options: [
        "Port": 8080,
        "BindToLocalhost": true
        ])
} catch {
    // handle error
}

Also, if Arbitrary Loads are disabled (probably), add "localhost" to NSExceptionDomains in info.plist

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSExceptionDomains</key>
    <dict>
        <key>localhost</key>
        <dict>
            <key>NSIncludesSubdomains</key>
            <true/>
            <key>NSExceptionAllowsInsecureHTTPLoads</key>
            <true/>
        </dict>
    </dict>
    <key>NSAllowsArbitraryLoads</key>
    <false/>
</dict>

This saved my life loading a webpage in a webview from local. It crashed when not in WiFi but this solved it. — juanjovn, May 22 '21 at 11:20

yeahdixon · Accepted Answer · 2016-07-15T02:37:09.327

1

serverUrl is null, but good ol local host works :

localhost://

Also available was the bonjour service url that is served up

func webServerDidCompleteBonjourRegistration(server: GCDWebServer!) {

    if(self.serverURL == nil){
        self.serverURL=self.webServer!.bonjourServerURL
        print(self.serverURL)
        self.initWebView()
    }


}

that got things running locally with wifi off.

edited Jul 15 '16 at 02:37

answered Jul 15 '16 at 02:26

yeahdixon

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score 1 · Answer 3 · answered Jul 15 '16 at 03:59

This is expected behavior although the docs could be more clear on this.

- (NSURL*)serverURL is just a convenience method that returns the primary IP address of your device appended with the server port. If your device is not connected to a network, it will return nil. See the implementation of GCDWebServerGetPrimaryIPAddress().

If this method returns returns nil, it simply means either the server is not running or it doesn't appear to have an external facing IP i.e. it's only reachable through localhost.

score 0 · Answer 4 · answered Mar 15 '19 at 22:07

0

Using the URL http://127.0.0.1:8080/ was the only option that worked for me when not on wifi.

answered Mar 15 '19 at 22:07

neave

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GDCWebserver serverURL is null when wifi is turned off

4 Answers4