SSDPClient

SSDP client for Swift using the Swift Package Manager. Works on iOS, macOS, tvOS, watchOS and Linux.

Installation

SSDPClient is available through Swift Package Manager. To install it, add the following line to your Package.swift dependencies:

.package(url: "https://github.com/pierrickrouxel/SSDPClient.git", from: "1.0.0")

Usage

SSDPClient can be used to discover SSDP devices and services :

import SSDPClient

class ServiceDiscovery {
    let client = SSDPDiscovery()

    init() {
        self.client.delegate = self
        self.client.discoverService()
    }
}

To handle the discovery implement the SSDPDiscoveryDelegate protocol :

extension ServiceDiscovery: SSDPDiscoveryDelegate {
    func ssdpDiscovery(_: SSDPDiscovery, didDiscoverService: SSDPService) {
        // ...
    }
}

Discovery

SSDPDiscovery provides two instance methods to discover services :

• discoverService(forDuration duration: TimeInterval = 10, searchTarget: String = "ssdp:all") - Discover SSDP services for a duration.

• stop() - Stop the discovery before the end.

Delegate

The SSDPDiscoveryDelegate protocol defines delegate methods that you should implement when using SSDPDiscovery discover tasks :

• func ssdpDiscovery(_ discovery: SSDPDiscovery, didDiscoverService service: SSDPService) - Tells the delegate a requested service has been discovered.

• func ssdpDiscovery(_ discovery: SSDPDiscovery, didFinishWithError error: Error) - Tells the delegate that the discovery ended due to an error.

• func ssdpDiscoveryDidStart(_ discovery: SSDPDiscovery) - Tells the delegate that the discovery has started.

• func ssdpDiscoveryDidFinish(_ discovery: SSDPDiscovery) - Tells the delegate that the discovery has finished.

Service

SSDPService is the discovered service. It contains the following attributes :

• host: String - The host of service
• location: String? - The value of LOCATION header
• server: String? - The value of SERVER header
• searchTarget: String? - The value of ST header
• uniqueServiceName: String? - The value of USN header
• responseHeaders: [String: String]? - Key-Value pairs of all original response headers

Test

Run test:

swift test

Troubleshooting

The application crash with error code -9982 Bad file descriptor

iOS 14.0+

If you are targeting iOS 14.0+ you will need to request a special Multicast Entitlement from Apple:

com.apple.developer.networking.multicast

Without the entitlement, you will not be able to test on an actual device; but you can still test in Simulator.

Regarding the local network authorization access, you do not need to explicitly ask for it; the OS will ask the user upon the first time you attempt to access the local network. It's best practice that you provide your own description in the Info.plist with the key NSLocalNetworkUsageDescription.

< iOS 14.0

You probably run a security issue. You should grant the local network authorization access.

You can handle this error using the following code:

let authorization = LocalNetworkAuthorization()
authorization.requestAuthorization { granted in
    if granted {
        print("Permission Granted")
        let discovery = ServiceDiscovery(delegate: self)
        discovery.start()
    } else {
        print("Permission denied")
    }
}