feat: replace libcurl with .NET HttpClient for sentry-native (#4222)

* poc: custom http transport for sentry-native to eliminate curl

* Replace StringContent with self-made UnmanagedHttpContent to avoid copy

* Update CONTRIBUTING.md

* ci: no need to install libcurl4-openssl-dev anymore

* mark UnmanagedHttpContent sealed

* fix UnmanagedHttpContent.TryComputeLength return value

* add diagnostic log message for native transport exceptions

* await async exceptions

* add unsafe CreateStream() helper

* clear the pointer after dispose

* apply discussed changes

* throw ObjectDisposedException if already disposed

* ObjectDisposedException.ThrowIf() is available in net7.0+

Author: jpnurmi

.github/workflows/build.yml

@@ -53,12 +53,6 @@ jobs:
         if: ${{ !matrix.container }}
         uses: ./.github/actions/freediskspace
 
-      - name: Install build dependencies
-        if: steps.cache.outputs.cache-hit != 'true' && runner.os == 'Linux' && !matrix.container
-        run: |
-          sudo apt update
-          sudo apt install libcurl4-openssl-dev
-
       - run: scripts/build-sentry-native.ps1
         if: steps.cache.outputs.cache-hit != 'true'
         shell: pwsh
@@ -239,12 +233,6 @@ jobs:
           name: ${{ github.sha }}
           path: src
 
-      - name: Install build dependencies
-        if: runner.os == 'Linux' && !matrix.container
-        run: |
-          sudo apt update
-          sudo apt install libcurl4-openssl-dev
-
       - name: Setup Environment
         uses: ./.github/actions/environment
 

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Features
 
 - Rename MemoryInfo.AllocatedBytes to MemoryInfo.TotalAllocatedBytes ([#4243](https://github.com/getsentry/sentry-dotnet/pull/4243))
+- Replace libcurl with .NET HttpClient for sentry-native ([#4222](https://github.com/getsentry/sentry-dotnet/pull/4222))
 
 ### Fixes
 

CONTRIBUTING.md

@@ -32,15 +32,13 @@ For big feature it's advised to raise an issue to discuss it first.
 
 * [`pwsh`](https://github.com/PowerShell/PowerShell#get-powershell) Core version 6 or later on PATH.
 
-* `CMake` on PATH. On Windows you can install the [C++ CMake tools for Windows](https://learn.microsoft.com/en-us/cpp/build/cmake-projects-in-visual-studio?view=msvc-170#installation). On macOS you can use your favourite package manager (e.g. `brew install cmake`).
+* `CMake` on PATH. On Windows you can install the [C++ CMake tools for Windows](https://learn.microsoft.com/en-us/cpp/build/cmake-projects-in-visual-studio?view=msvc-170#installation). On macOS and Linux you can use your favourite package manager (e.g. `brew install cmake` or `apt install cmake`).
 
 * On Windows:
   - [.NET Framework](https://dotnet.microsoft.com/download/dotnet-framework) 4.6.2 or higher.
   - `Sentry.DiagnosticSource.IntegrationTests.csproj` uses [SQL LocalDb](https://docs.microsoft.com/sql/database-engine/configure-windows/sql-server-express-localdb) - [download SQL LocalDB 2019](https://download.microsoft.com/download/7/c/1/7c14e92e-bdcb-4f89-b7cf-93543e7112d1/SqlLocalDB.msi). To avoid running these tests, unload `Sentry.DiagnosticSource.IntegrationTests.csproj` from the solution.
 * On macOS/Linux
   - [Mono 6 or higher](https://www.mono-project.com/download/stable) to run the unit tests on the `net4x` targets.
-* On Linux
-  - **curl** and **zlib** libraries (e.g. on Ubuntu: libcurl4-openssl-dev, libz-dev) to build the [sentry-native](https://github.com/getsentry/sentry-native/) module.
 
 ## .NET MAUI Requirements
 

scripts/build-sentry-native.ps1

@@ -69,6 +69,7 @@ try
         -D SENTRY_SDK_NAME=sentry.native.dotnet `
         -D SENTRY_BUILD_SHARED_LIBS=0 `
         -D SENTRY_BACKEND=inproc `
+        -D SENTRY_TRANSPORT=none `
         $additionalArgs
 
     cmake `

src/Sentry/Http/HttpTransportBase.cs

@@ -187,20 +187,8 @@ protected internal virtual HttpRequestMessage CreateRequest(Envelope envelope)
             throw new InvalidOperationException("The DSN is expected to be set at this point.");
         }
 
-        var dsn = Dsn.Parse(_options.Dsn);
-        var authHeader =
-            $"Sentry sentry_version={_options.SentryVersion}," +
-            $"sentry_client={SdkVersion.Instance.Name}/{SdkVersion.Instance.Version}," +
-            $"sentry_key={dsn.PublicKey}" +
-            (dsn.SecretKey is { } secretKey ? $",sentry_secret={secretKey}" : null);
-
-        return new HttpRequestMessage
-        {
-            RequestUri = dsn.GetEnvelopeEndpointUri(),
-            Method = HttpMethod.Post,
-            Headers = { { "X-Sentry-Auth", authHeader } },
-            Content = new EnvelopeHttpContent(envelope, _options.DiagnosticLogger, _clock)
-        };
+        var content = new EnvelopeHttpContent(envelope, _options.DiagnosticLogger, _clock);
+        return _options.CreateHttpRequest(content);
     }
 
     /// <summary>

src/Sentry/Platforms/Native/CFunctions.cs

@@ -139,6 +139,14 @@ public static bool Init(SentryOptions options)
             }
         }
 
+        unsafe
+        {
+            var cTransport = sentry_transport_new(&nativeTransport);
+            sentry_transport_set_state(cTransport, GCHandle.ToIntPtr(GCHandle.Alloc(options)));
+            sentry_transport_set_free_func(cTransport, &nativeTransportFree);
+            sentry_options_set_transport(cOptions, cTransport);
+        }
+
         options.DiagnosticLogger?.LogDebug("Initializing sentry native");
         return 0 == sentry_init(cOptions);
     }
@@ -364,6 +372,70 @@ internal struct sentry_value_t
     [DllImport("sentry-native")]
     private static extern void sentry_options_set_auto_session_tracking(IntPtr options, int debug);
 
+    [DllImport("sentry-native")]
+    private static extern void sentry_options_set_transport(IntPtr options, IntPtr transport);
+
+    [DllImport("sentry-native")]
+    private static extern unsafe IntPtr sentry_transport_new(delegate* unmanaged<IntPtr, IntPtr, void> sendFunc);
+
+    [DllImport("sentry-native")]
+    private static extern void sentry_transport_set_state(IntPtr transport, IntPtr state);
+
+    [DllImport("sentry-native")]
+    private static extern unsafe void sentry_transport_set_free_func(IntPtr transport, delegate* unmanaged<IntPtr, void> freeFunc);
+
+    [DllImport("sentry-native")]
+    private static extern IntPtr sentry_envelope_serialize(IntPtr envelope, out UIntPtr sizeOut);
+
+    [DllImport("sentry-native")]
+    private static extern void sentry_envelope_free(IntPtr envelope);
+
+    [DllImport("sentry-native")]
+    internal static extern void sentry_free(IntPtr ptr);
+
+    [UnmanagedCallersOnly]
+    private static void nativeTransport(IntPtr envelope, IntPtr state)
+    {
+        var options = GCHandle.FromIntPtr(state).Target as SentryOptions;
+        try
+        {
+            if (options is not null)
+            {
+                var data = sentry_envelope_serialize(envelope, out var size);
+                using var content = new UnmanagedHttpContent(data, (int)size, options.DiagnosticLogger);
+
+                using var client = options.GetHttpClient();
+                using var request = options.CreateHttpRequest(content);
+#if NET5_0_OR_GREATER
+                var response = client.Send(request);
+#else
+                var response = client.SendAsync(request).GetAwaiter().GetResult();
+#endif
+                response.EnsureSuccessStatusCode();
+            }
+        }
+        catch (HttpRequestException e)
+        {
+            options?.DiagnosticLogger?.LogError(e, "Failed to send native envelope.");
+        }
+        catch (Exception e)
+        {
+            // never allow an exception back to native code - it would crash the app
+            options?.DiagnosticLogger?.LogError(e, "Exception in native transport callback. The native envelope will not be sent.");
+        }
+        finally
+        {
+            sentry_envelope_free(envelope);
+        }
+    }
+
+    [UnmanagedCallersOnly]
+    private static void nativeTransportFree(IntPtr state)
+    {
+        var handle = GCHandle.FromIntPtr(state);
+        handle.Free();
+    }
+
     [DllImport("sentry-native")]
     private static extern unsafe void sentry_options_set_logger(IntPtr options, delegate* unmanaged/*[Cdecl]*/<int, IntPtr, IntPtr, IntPtr, void> logger, IntPtr userData);
 

src/Sentry/Platforms/Native/UnmanagedHttpContent.cs

@@ -0,0 +1,78 @@
+using Sentry.Extensibility;
+
+namespace Sentry.Native;
+
+internal sealed class UnmanagedHttpContent : SerializableHttpContent
+{
+    private IntPtr _content;
+    private readonly int _length = 0;
+    private readonly IDiagnosticLogger? _logger;
+
+    public UnmanagedHttpContent(IntPtr content, int length, IDiagnosticLogger? logger)
+    {
+        _content = content;
+        _length = length;
+        _logger = logger;
+    }
+
+    ~UnmanagedHttpContent()
+    {
+        Dispose(false);
+    }
+
+    protected override async Task SerializeToStreamAsync(Stream stream, TransportContext? context)
+    {
+        ThrowIfObjectDisposed();
+        try
+        {
+            using var unmanagedStream = CreateStream();
+            await unmanagedStream.CopyToAsync(stream).ConfigureAwait(false);
+        }
+        catch (Exception e)
+        {
+            _logger?.LogError(e, "Failed to serialize unmanaged content into the network stream");
+            throw;
+        }
+    }
+
+    protected override void SerializeToStream(Stream stream, TransportContext? context, CancellationToken cancellationToken)
+    {
+        ThrowIfObjectDisposed();
+        try
+        {
+            using var unmanagedStream = CreateStream();
+            unmanagedStream.CopyTo(stream);
+        }
+        catch (Exception e)
+        {
+            _logger?.LogError(e, "Failed to serialize unmanaged content into the network stream");
+            throw;
+        }
+    }
+
+    protected override bool TryComputeLength(out long length)
+    {
+        length = _length;
+        return true;
+    }
+
+    protected override void Dispose(bool disposing)
+    {
+        IntPtr content = Interlocked.Exchange(ref _content, IntPtr.Zero);
+        C.sentry_free(content);
+        base.Dispose(disposing);
+    }
+
+    private unsafe UnmanagedMemoryStream CreateStream()
+    {
+        return new UnmanagedMemoryStream((byte*)_content.ToPointer(), _length);
+    }
+
+    private void ThrowIfObjectDisposed()
+    {
+        if (_content == IntPtr.Zero)
+        {
+            throw new ObjectDisposedException(GetType().FullName);
+        }
+    }
+}

src/Sentry/Platforms/Native/buildTransitive/Sentry.Native.targets

@@ -36,8 +36,6 @@
   <ItemGroup Condition="'$(FrameworkSupportsNative)' == 'true' and ('$(RuntimeIdentifier)' == 'linux-x64' or '$(RuntimeIdentifier)' == 'linux-arm64')">
     <DirectPInvoke Include="sentry-native" />
     <NativeLibrary Include="$(MSBuildThisFileDirectory)..\sentry-native\$(RuntimeIdentifier)\libsentry-native.a" />
-    <!-- See: https://github.com/dotnet/runtime/issues/97414 -->
-    <NativeSystemLibrary Include="curl" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(FrameworkSupportsNative)' == 'true' and '$(RuntimeIdentifier)' == 'linux-musl-x64'">
@@ -46,13 +44,10 @@
     <LinkerArg Include="-Wl,-Bstatic -Wl,--whole-archive -lunwind -Wl,--no-whole-archive -Wl,-Bdynamic" />
     <NativeSystemLibrary Include="lzma" />
     <NativeLibrary Include="$(MSBuildThisFileDirectory)..\sentry-native\linux-musl-x64\libsentry-native.a" />
-    <!-- See: https://github.com/dotnet/runtime/issues/97414 -->
-    <NativeSystemLibrary Include="curl" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(FrameworkSupportsNative)' == 'true' and ('$(RuntimeIdentifier)' == 'osx-x64' or '$(RuntimeIdentifier)' == 'osx-arm64')">
     <DirectPInvoke Include="sentry-native" />
     <NativeLibrary Include="$(MSBuildThisFileDirectory)..\sentry-native\osx\libsentry-native.a" />
-    <NativeSystemLibrary Include="curl" />
   </ItemGroup>
 </Project>

src/Sentry/SentryOptions.cs

@@ -245,6 +245,23 @@ internal HttpClient GetHttpClient()
         return factory.Create(this);
     }
 
+    internal HttpRequestMessage CreateHttpRequest(HttpContent content)
+    {
+        var authHeader =
+            $"Sentry sentry_version={SentryVersion}," +
+            $"sentry_client={SdkVersion.Instance.Name}/{SdkVersion.Instance.Version}," +
+            $"sentry_key={ParsedDsn.PublicKey}" +
+            (ParsedDsn.SecretKey is { } secretKey ? $",sentry_secret={secretKey}" : null);
+
+        return new HttpRequestMessage
+        {
+            RequestUri = ParsedDsn.GetEnvelopeEndpointUri(),
+            Method = HttpMethod.Post,
+            Headers = { { "X-Sentry-Auth", authHeader } },
+            Content = content
+        };
+    }
+
     /// <summary>
     /// Scope state processor.
     /// </summary>