Allow disabling remote config management explicitly

tracer/build/_build/docker/smoke.chiseled.dockerfile

@@ -59,6 +59,7 @@ ENV COMPlus_DbgEnableMiniDump=1
 ENV COMPlus_DbgMiniDumpType=4
 ENV DOTNET_DbgMiniDumpName=/dumps/coredump.%t.%p
 ENV DOTNET_EnableCrashReport=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.dd-dotnet.dockerfile

@@ -39,6 +39,7 @@ ENV COMPlus_DbgEnableMiniDump=1
 ENV COMPlus_DbgMiniDumpType=4
 ENV DOTNET_DbgMiniDumpName=/dumps/coredump.%t.%p
 ENV DOTNET_EnableCrashReport=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.dockerfile

@@ -34,6 +34,7 @@ ENV LD_PRELOAD=/opt/datadog/continuousprofiler/Datadog.Linux.ApiWrapper.x64.so
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.dotnet-tool.dockerfile

@@ -29,6 +29,7 @@ RUN mkdir -p /opt/datadog \
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 ENV ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.dotnet-tool.nuget.dockerfile

@@ -30,6 +30,7 @@ RUN mkdir -p /opt/datadog \
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 ENV ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.dotnet-tool.self-instrument.dockerfile

@@ -38,6 +38,7 @@ ENV LD_PRELOAD=/opt/datadog/continuousprofiler/Datadog.Linux.ApiWrapper.x64.so
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 ENV ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.nuget.dd-dotnet.dockerfile

@@ -38,6 +38,7 @@ ENV COMPlus_DbgEnableMiniDump=1
 ENV COMPlus_DbgMiniDumpType=4
 ENV DOTNET_DbgMiniDumpName=/dumps/coredump.%t.%p
 ENV DOTNET_EnableCrashReport=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.nuget.dockerfile

@@ -37,6 +37,7 @@ ENV DD_DOTNET_TRACER_HOME=/app/datadog
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.trimming.dockerfile

@@ -43,6 +43,7 @@ ENV LD_PRELOAD=/opt/datadog/continuousprofiler/Datadog.Linux.ApiWrapper.x64.so
 ENV DD_PROFILING_ENABLED=1
 ENV DD_APPSEC_ENABLED=1
 ENV DD_TRACE_DEBUG=1
+ENV DD_REMOTE_CONFIGURATION_ENABLED=0
 
 ## SSI variables
 ENV DD_INJECTION_ENABLED=tracer

tracer/build/_build/docker/smoke.windows.dd-dotnet.dockerfile

@@ -35,6 +35,7 @@ RUN mkdir /logs; \
 
 # Set the additional env vars
 ENV DD_TRACE_LOG_DIRECTORY="C:\logs" \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.windows.dockerfile

@@ -40,6 +40,7 @@ ENV DD_PROFILING_ENABLED=1 \
     CORECLR_ENABLE_PROFILING=1 \
     CORECLR_PROFILER={846F5F1C-F9AE-4B07-969E-05C26BC060D8} \
     DD_TRACE_LOG_DIRECTORY="C:\logs" \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.windows.dotnet-tool.dockerfile

@@ -39,6 +39,7 @@ RUN mkdir /logs; \
 ENV DD_PROFILING_ENABLED=1 \
     DD_TRACE_DEBUG=1 \
     DD_APPSEC_ENABLED=1 \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     DD_TRACE_LOG_DIRECTORY="C:\logs" \
     ASPNETCORE_URLS=http://localhost:5000
 

tracer/build/_build/docker/smoke.windows.fleet-installer.dockerfile

@@ -41,6 +41,7 @@ RUN mkdir /logs; \
 ENV DD_PROFILING_ENABLED=1 \
     DD_TRACE_DEBUG=1 \
     DD_APPSEC_ENABLED=1 \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     DD_TRACE_LOG_DIRECTORY="C:\logs"
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.windows.nuget.dd-dotnet.dockerfile

@@ -35,6 +35,7 @@ RUN mkdir /logs
 
 # Set the required env vars
 ENV DD_TRACE_LOG_DIRECTORY="C:\logs" \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.windows.nuget.dockerfile

@@ -44,6 +44,7 @@ ENV CORECLR_ENABLE_PROFILING=1 \
     DD_DOTNET_TRACER_HOME="c:\app\datadog" \
     DD_TRACE_LOG_DIRECTORY="C:\logs" \
     DD_PROFILING_ENABLED=1 \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/build/_build/docker/smoke.windows.tracer-home.dockerfile

@@ -47,6 +47,7 @@ ENV DD_PROFILING_ENABLED=1 \
     CORECLR_PROFILER={846F5F1C-F9AE-4B07-969E-05C26BC060D8} \
     DD_DOTNET_TRACER_HOME="c:\monitoring-home" \
     DD_TRACE_LOG_DIRECTORY="C:\logs" \
+    DD_REMOTE_CONFIGURATION_ENABLED=0 \
     ASPNETCORE_URLS=http://localhost:5000
 
 # Set a random env var we should ignore

tracer/src/Datadog.Trace/Configuration/ConfigurationKeys.Rcm.cs

@@ -12,6 +12,13 @@ internal static partial class ConfigurationKeys
     {
         internal static class Rcm
         {
+            /// <summary>
+            /// Is remote configuration management (RCM) enabled. Defaults to <c>true</c>. RCM requires
+            /// the use of the full agent, so will not always be available. This switch is primarily
+            /// intended for testing and for explicitly disabling RCM even though it is available.
+            /// </summary>
+            public const string RemoteConfigurationEnabled = "DD_REMOTE_CONFIGURATION_ENABLED";
+
             /// <summary>
             /// Configuration key for RCM poll interval (in seconds).
             /// Default value is 5 s

tracer/src/Datadog.Trace/Configuration/TracerSettings.cs

@@ -663,6 +663,8 @@ _ when x.ToBoolean() is { } boolean => boolean,
                                      converter: x => ToDbmPropagationInput(x) ?? ParsingResult<DbmPropagationLevel>.Failure(),
                                      validator: null);
 
+            RemoteConfigurationEnabled = config.WithKeys(ConfigurationKeys.Rcm.RemoteConfigurationEnabled).AsBool(true);
+
             TraceId128BitGenerationEnabled = config
                                             .WithKeys(ConfigurationKeys.FeatureFlags.TraceId128BitGenerationEnabled)
                                             .AsBool(true);
@@ -1227,6 +1229,11 @@ public bool DiagnosticSourceEnabled
         /// </summary>
         internal SchemaVersion MetadataSchemaVersion { get; }
 
+        /// <summary>
+        /// Gets a value indicating whether remote configuration has been explicitly disabled.
+        /// </summary>
+        internal bool RemoteConfigurationEnabled { get; }
+
         /// <summary>
         /// Gets the disabled ADO.NET Command Types that won't have spans generated for them.
         /// </summary>
@@ -1238,9 +1245,11 @@ public bool DiagnosticSourceEnabled
 
         /// <summary>
         /// Gets a value indicating whether remote configuration is potentially available.
-        /// RCM requires the "full" agent (not just the trace agent), so is not available in some scenarios
+        /// RCM requires the "full" agent (not just the trace agent), so is not available in some scenarios.
+        /// It may also be explicitly disabled
         /// </summary>
         internal bool IsRemoteConfigurationAvailable =>
+            RemoteConfigurationEnabled &&
             !(IsRunningInAzureAppService
            || IsRunningMiniAgentInAzureFunctions
            || IsRunningInGCPFunctions

tracer/test/Datadog.Trace.Tests/Configuration/TracerSettingsTests.cs

@@ -1065,6 +1065,22 @@ public void TraceId128BitLoggingEnabled(string value, bool expected)
             settings.TraceId128BitLoggingEnabled.Should().Be(expected);
         }
 
+        [Theory]
+        [PairwiseData]
+        public void IsRemoteConfigurationAvailable(bool? overrideValue, bool? isRunningInAas)
+        {
+            var source = CreateConfigurationSource(
+                (ConfigurationKeys.AzureAppService.AzureAppServicesContextKey, AsString(isRunningInAas)),
+                (ConfigurationKeys.Rcm.RemoteConfigurationEnabled, AsString(overrideValue)));
+            var settings = new TracerSettings(source);
+
+            // Default is "rcm is enabled" and "we're not in AAS"
+            var expected = (overrideValue ?? true) && !(isRunningInAas ?? false);
+            settings.IsRemoteConfigurationAvailable.Should().Be(expected);
+
+            static string AsString(bool? value) => value.HasValue ? (value.Value ? "1" : "0") : string.Empty;
+        }
+
         [Fact]
         public void RecordsTelemetryAboutTfm()
         {

tracer/test/Datadog.Trace.Tests/Telemetry/config_norm_rules.json

@@ -571,6 +571,7 @@
   "DD_TRACE_LOGFILE_RETENTION_DAYS": "trace_log_file_retention_days",
   "DD_TRACE_LOG_SINKS": "trace_log_sinks",
   "DD_TRACE_COMMANDS_COLLECTION_ENABLED": "trace_commands_collection_enabled",
+  "DD_REMOTE_CONFIGURATION_ENABLED": "remote_config_enabled",
   "DD_REMOTE_CONFIG_POLL_INTERVAL_SECONDS": "remote_config_poll_interval",
   "DD_INTERNAL_RCM_POLL_INTERVAL": "remote_config_poll_interval",
   "trace.128_bit_traceid_logging_enabled": "trace_128_bits_id_logging_enabled",