Obtain distro version from the informational assembly version (#66)

Author: pyohannes

.markdownlint.yaml

@@ -5,3 +5,7 @@ default: true
 MD013:
   code_blocks: false
   tables: false
+
+# Allow same headers for non-siblings, e. g. in the CHANGELOG
+MD024:
+  siblings_only: true

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 ## Unreleased
 
+### Bug fixes
+
+* [#65](https://github.com/grafana/grafana-opentelemetry-dotnet/issues/65):
+  Using the distribution broke self-contained applications. This has been fixed
+  by using a different way to determine the distribution version.
+* [#64](https://github.com/grafana/grafana-opentelemetry-dotnet/issues/64): The
+  version in `telemetry.distro.version` contained a trailing commit hash. This
+  commit hash is removed now before populating the attribute.
+
 ## 0.6.0-beta.2
 
 ### New features

src/Grafana.OpenTelemetry.Base/GrafanaOpenTelemetryResourceDetector.cs

@@ -27,18 +27,33 @@ public GrafanaOpenTelemetryResourceDetector(GrafanaOpenTelemetrySettings setting
 
         public Resource Detect()
         {
-            var assembly = typeof(GrafanaOpenTelemetryResourceDetector).Assembly;
-
             var attributes = new List<KeyValuePair<string, object>>(new KeyValuePair<string, object>[]
             {
                 new KeyValuePair<string, object>(ResourceKey_DistroName, ResourceValue_DistroName),
-                new KeyValuePair<string, object>(ResourceKey_DistroVersion, FileVersionInfo.GetVersionInfo(assembly.Location).ProductVersion),
+                new KeyValuePair<string, object>(ResourceKey_DistroVersion, GetDistroVersion()),
                 new KeyValuePair<string, object>(ResourceKey_DeploymentEnvironment, _settings.DeploymentEnvironment)
             });
 
             attributes.AddRange(_settings.ResourceAttributes);
 
             return new Resource(attributes);
         }
+
+        static internal string GetDistroVersion()
+        {
+            var informationalVersion = typeof(GrafanaOpenTelemetryResourceDetector)
+                .Assembly
+                .GetCustomAttribute<AssemblyInformationalVersionAttribute>()?
+                .InformationalVersion;
+
+            if (string.IsNullOrWhiteSpace(informationalVersion))
+            {
+                informationalVersion = "0.0.0";
+            }
+
+            // A Git hash is appended to the informational version after a "+" character. That's of limited use and
+            // therefore removed here.
+            return informationalVersion.Split('+')[0];
+        }
     }
 }