From b0e27ce7f0e2615eadeaa4b401c108c536b94c18 Mon Sep 17 00:00:00 2001
From: Cijo Thomas <cithomas@microsoft.com>
Date: Mon, 19 Jul 2021 23:16:46 -0700
Subject: [PATCH] Remove Net452 from API project

---
 .../.publicApi/net452/PublicAPI.Unshipped.txt |  0
 .../{net452 => net461}/PublicAPI.Shipped.txt  |  0
 .../.publicApi/net461/PublicAPI.Unshipped.txt |  4 +++
 src/OpenTelemetry.Api/CHANGELOG.md            |  3 +++
 .../Context/AsyncLocalRuntimeContextSlot.cs   |  2 --
 .../Context/RemotingRuntimeContextSlot.cs     |  2 +-
 .../Context/RuntimeContext.cs                 |  4 ---
 .../OpenTelemetry.Api.csproj                  |  8 +++++-
 .../OpenTelemetry.Exporter.Zipkin.csproj      |  2 +-
 .../ZipkinExporter.cs                         | 25 -------------------
 .../ZipkinExporterOptions.cs                  |  4 ---
 11 files changed, 16 insertions(+), 38 deletions(-)
 delete mode 100644 src/OpenTelemetry.Api/.publicApi/net452/PublicAPI.Unshipped.txt
 rename src/OpenTelemetry.Api/.publicApi/{net452 => net461}/PublicAPI.Shipped.txt (100%)
 create mode 100644 src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Unshipped.txt

diff --git a/src/OpenTelemetry.Api/.publicApi/net452/PublicAPI.Unshipped.txt b/src/OpenTelemetry.Api/.publicApi/net452/PublicAPI.Unshipped.txt
deleted file mode 100644
index e69de29bb2d..00000000000
diff --git a/src/OpenTelemetry.Api/.publicApi/net452/PublicAPI.Shipped.txt b/src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Shipped.txt
similarity index 100%
rename from src/OpenTelemetry.Api/.publicApi/net452/PublicAPI.Shipped.txt
rename to src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Shipped.txt
diff --git a/src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Unshipped.txt b/src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Unshipped.txt
new file mode 100644
index 00000000000..edd1a3f6ec6
--- /dev/null
+++ b/src/OpenTelemetry.Api/.publicApi/net461/PublicAPI.Unshipped.txt
@@ -0,0 +1,4 @@
+override OpenTelemetry.Context.AsyncLocalRuntimeContextSlot<T>.Get() -> T
+override OpenTelemetry.Context.AsyncLocalRuntimeContextSlot<T>.Set(T value) -> void
+OpenTelemetry.Context.AsyncLocalRuntimeContextSlot<T>
+OpenTelemetry.Context.AsyncLocalRuntimeContextSlot<T>.AsyncLocalRuntimeContextSlot(string name) -> void
diff --git a/src/OpenTelemetry.Api/CHANGELOG.md b/src/OpenTelemetry.Api/CHANGELOG.md
index 6f68c7e29e8..c14b144e382 100644
--- a/src/OpenTelemetry.Api/CHANGELOG.md
+++ b/src/OpenTelemetry.Api/CHANGELOG.md
@@ -9,6 +9,9 @@ please check the latest changes
 
 ## Unreleased
 
+* Removes .NET Framework 4.5.2 support. The minimum .NET Framework
+  version supported is .NET 4.6.1. ([#2138](https://github.com/open-telemetry/opentelemetry-dotnet/issues/2138))
+
 ## 1.1.0
 
 Released 2021-Jul-12
diff --git a/src/OpenTelemetry.Api/Context/AsyncLocalRuntimeContextSlot.cs b/src/OpenTelemetry.Api/Context/AsyncLocalRuntimeContextSlot.cs
index abfce0c564e..de5c5083a13 100644
--- a/src/OpenTelemetry.Api/Context/AsyncLocalRuntimeContextSlot.cs
+++ b/src/OpenTelemetry.Api/Context/AsyncLocalRuntimeContextSlot.cs
@@ -14,7 +14,6 @@
 // limitations under the License.
 // </copyright>
 
-#if !NET452
 using System.Runtime.CompilerServices;
 using System.Threading;
 
@@ -53,4 +52,3 @@ public override void Set(T value)
         }
     }
 }
-#endif
diff --git a/src/OpenTelemetry.Api/Context/RemotingRuntimeContextSlot.cs b/src/OpenTelemetry.Api/Context/RemotingRuntimeContextSlot.cs
index 277b6e61fdf..f589d9900bc 100644
--- a/src/OpenTelemetry.Api/Context/RemotingRuntimeContextSlot.cs
+++ b/src/OpenTelemetry.Api/Context/RemotingRuntimeContextSlot.cs
@@ -14,7 +14,7 @@
 // limitations under the License.
 // </copyright>
 
-#if NET452
+#if NET461
 using System.Collections;
 using System.Reflection;
 using System.Runtime.CompilerServices;
diff --git a/src/OpenTelemetry.Api/Context/RuntimeContext.cs b/src/OpenTelemetry.Api/Context/RuntimeContext.cs
index 47e48c65a8a..b0110e5ac3c 100644
--- a/src/OpenTelemetry.Api/Context/RuntimeContext.cs
+++ b/src/OpenTelemetry.Api/Context/RuntimeContext.cs
@@ -30,11 +30,7 @@ public static class RuntimeContext
         /// <summary>
         /// Gets or sets the actual context carrier implementation.
         /// </summary>
-#if !NET452
         public static Type ContextSlotType { get; set; } = typeof(AsyncLocalRuntimeContextSlot<>);
-#else
-        public static Type ContextSlotType { get; set; } = typeof(RemotingRuntimeContextSlot<>);
-#endif
 
         /// <summary>
         /// Register a named context slot.
diff --git a/src/OpenTelemetry.Api/OpenTelemetry.Api.csproj b/src/OpenTelemetry.Api/OpenTelemetry.Api.csproj
index a71a29946db..d5d3e19631f 100644
--- a/src/OpenTelemetry.Api/OpenTelemetry.Api.csproj
+++ b/src/OpenTelemetry.Api/OpenTelemetry.Api.csproj
@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;net452</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
     <Description>OpenTelemetry .NET API</Description>
     <RootNamespace>OpenTelemetry</RootNamespace>
 
@@ -8,6 +8,12 @@
     <MinVerTagPrefix>core-</MinVerTagPrefix>
   </PropertyGroup>
 
+  <!--Do not run ApiCopmat for net461 as this is newly added. There is no existing contract for net461 against which we could compare the implementation.
+  Remove this property once we have released a stable net461 version.-->
+  <PropertyGroup Condition="'$(TargetFramework)' == 'net461'">
+    <RunApiCompat>false</RunApiCompat>
+  </PropertyGroup>
+
   <ItemGroup>
     <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="$(SystemDiagnosticSourcePkgVer)" />
     <PackageReference Include="System.Reflection.Emit.Lightweight" Version="$(SystemReflectionEmitLightweightPkgVer)" />
diff --git a/src/OpenTelemetry.Exporter.Zipkin/OpenTelemetry.Exporter.Zipkin.csproj b/src/OpenTelemetry.Exporter.Zipkin/OpenTelemetry.Exporter.Zipkin.csproj
index 51e3ac63329..bd6cfc37423 100644
--- a/src/OpenTelemetry.Exporter.Zipkin/OpenTelemetry.Exporter.Zipkin.csproj
+++ b/src/OpenTelemetry.Exporter.Zipkin/OpenTelemetry.Exporter.Zipkin.csproj
@@ -22,7 +22,7 @@
 
   <ItemGroup>
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry\OpenTelemetry.csproj" />
-    <PackageReference Include="System.Text.Json" Version="$(SystemTextJsonPkgVer)" Condition="'$(TargetFramework)' != 'net452'" />
+    <PackageReference Include="System.Text.Json" Version="$(SystemTextJsonPkgVer)" />
   </ItemGroup>
 
 </Project>
diff --git a/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporter.cs b/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporter.cs
index 43f389ded2d..08e5530bae5 100644
--- a/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporter.cs
+++ b/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporter.cs
@@ -22,11 +22,7 @@
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Net.Sockets;
-#if NET452
-using Newtonsoft.Json;
-#else
 using System.Text.Json;
-#endif
 using System.Threading;
 using System.Threading.Tasks;
 using OpenTelemetry.Exporter.Zipkin.Implementation;
@@ -40,9 +36,7 @@ namespace OpenTelemetry.Exporter
     public class ZipkinExporter : BaseExporter<Activity>
     {
         private readonly ZipkinExporterOptions options;
-#if !NET452
         private readonly int maxPayloadSizeInBytes;
-#endif
         private readonly HttpClient httpClient;
 
         /// <summary>
@@ -53,9 +47,7 @@ public class ZipkinExporter : BaseExporter<Activity>
         public ZipkinExporter(ZipkinExporterOptions options, HttpClient client = null)
         {
             this.options = options ?? throw new ArgumentNullException(nameof(options));
-#if !NET452
             this.maxPayloadSizeInBytes = (!options.MaxPayloadSizeInBytes.HasValue || options.MaxPayloadSizeInBytes <= 0) ? ZipkinExporterOptions.DefaultMaxPayloadSizeInBytes : options.MaxPayloadSizeInBytes.Value;
-#endif
             this.httpClient = client ?? new HttpClient();
         }
 
@@ -196,12 +188,7 @@ private class JsonContent : HttpContent
 
             private readonly ZipkinExporter exporter;
             private readonly Batch<Activity> batch;
-
-#if NET452
-            private JsonWriter writer;
-#else
             private Utf8JsonWriter writer;
-#endif
 
             public JsonContent(ZipkinExporter exporter, in Batch<Activity> batch)
             {
@@ -213,10 +200,6 @@ public JsonContent(ZipkinExporter exporter, in Batch<Activity> batch)
 
             protected override Task SerializeToStreamAsync(Stream stream, TransportContext context)
             {
-#if NET452
-                StreamWriter streamWriter = new StreamWriter(stream);
-                this.writer = new JsonTextWriter(streamWriter);
-#else
                 if (this.writer == null)
                 {
                     this.writer = new Utf8JsonWriter(stream);
@@ -225,7 +208,6 @@ protected override Task SerializeToStreamAsync(Stream stream, TransportContext c
                 {
                     this.writer.Reset(stream);
                 }
-#endif
 
                 this.writer.WriteStartArray();
 
@@ -236,23 +218,16 @@ protected override Task SerializeToStreamAsync(Stream stream, TransportContext c
                     zipkinSpan.Write(this.writer);
 
                     zipkinSpan.Return();
-#if !NET452
                     if (this.writer.BytesPending >= this.exporter.maxPayloadSizeInBytes)
                     {
                         this.writer.Flush();
                     }
-#endif
                 }
 
                 this.writer.WriteEndArray();
 
                 this.writer.Flush();
-
-#if NET452
-                return Task.FromResult(true);
-#else
                 return Task.CompletedTask;
-#endif
             }
 
             protected override bool TryComputeLength(out long length)
diff --git a/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporterOptions.cs b/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporterOptions.cs
index 53ed4c73f83..ea19973fd42 100644
--- a/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporterOptions.cs
+++ b/src/OpenTelemetry.Exporter.Zipkin/ZipkinExporterOptions.cs
@@ -24,9 +24,7 @@ namespace OpenTelemetry.Exporter
     /// </summary>
     public sealed class ZipkinExporterOptions
     {
-#if !NET452
         internal const int DefaultMaxPayloadSizeInBytes = 4096;
-#endif
 
         /// <summary>
         /// Gets or sets Zipkin endpoint address. See https://zipkin.io/zipkin-api/#/default/post_spans.
@@ -39,12 +37,10 @@ public sealed class ZipkinExporterOptions
         /// </summary>
         public bool UseShortTraceIds { get; set; }
 
-#if !NET452
         /// <summary>
         /// Gets or sets the maximum payload size in bytes. Default value: 4096.
         /// </summary>
         public int? MaxPayloadSizeInBytes { get; set; } = DefaultMaxPayloadSizeInBytes;
-#endif
 
         /// <summary>
         /// Gets or sets the export processor type to be used with Zipkin Exporter.