easier gzip

ios/Capacitor/Capacitor/Plugins/CapacitorUrlRequest.swift

@@ -1,4 +1,5 @@
 import Foundation
+import Compression
 
 open class CapacitorUrlRequest: NSObject, URLSessionTaskDelegate {
     public var request: URLRequest
@@ -125,12 +126,47 @@ open class CapacitorUrlRequest: NSObject, URLSessionTaskDelegate {
         }
     }
 
+    private func gzipCompress(data: Data) throws -> Data {
+        let stream = OutputStream(toMemory: ())
+        let windowBits = Int32(15)
+        let level = Int32(COMPRESSION_LEVEL_DEFAULT)
+        let strategy = Int32(COMPRESSION_STRATEGY_DEFAULT)
+        let status = compression_stream_init(&stream.stream, COMPRESSION_STREAM_ENCODE, COMPRESSION_ZLIB, windowBits)
+        guard status == COMPRESSION_STATUS_OK else {
+            throw NSError(domain: "compression_stream_init", code: Int(status), userInfo: nil)
+        }
+        var compressedData = Data()
+        let bufferSize = 1024 * 1024
+        var buffer = UnsafeMutablePointer<UInt8>.allocate(capacity: bufferSize)
+        defer {
+            buffer.deallocate()
+        }
+        stream.open()
+        defer {
+            stream.close()
+        }
+        var inputSize = data.count
+        var outputSize = 0
+        while inputSize > 0 {
+            let count = min(inputSize, bufferSize)
+            data.copyBytes(to: buffer, from: 0..<count)
+            let flags: Int32 = inputSize == count ? Int32(COMPRESSION_STREAM_FINALIZE.rawValue) : 0
+            let result = compression_stream_process(&stream.stream, flags, buffer, count, compressedData.withUnsafeMutableBytes { $0.baseAddress! }, compressedData.count, &outputSize)
+            guard result == COMPRESSION_STATUS_OK else {
+                throw NSError(domain: "compression_stream_process", code: Int(result), userInfo: nil)
+            }
+            compressedData.count += outputSize
+            inputSize -= count
+        }
+        return compressedData
+    }
+
     private func getRequestDataAsGzip(_ body: JSValue) throws -> Data? {
         // string to Data
         let dataBody = try getRequestDataAsString(body)
 
         // gzip compression
-        let compressedData: Data = try dataBody.gzipped()
+        let compressedData: Data = self.gzipCompress(dataBody)
         return compressedData
     }