Remove Resource public ctor as Provider expects ResourceBuilder now

[cijothomas]

Fixes #.

Changes

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[CodeBlanch]

I left the ctor public for two reasons:

1. Spec specifically calls out a create method on Resource that accepts attributes. The ctor satisfied that nicely. Really Resource class is highly compliant with the spec.
2. You can new up a Resource and pass it to the AddResource method on ResourceBuilder. User is free to do this, if they want to:

   var builder = ResourceBuilder.CreateEmpty()
      .AddService("MyService")
      .AddResource(new Resource(new Dictionary<string, object> { ["Key1"] = "Value1" }))
      .AddResource(new Resource(new Dictionary<string, object> { ["Key2"] = "Value2" }));

If you still want to make internal though, fine with me.

[cijothomas]

I left the ctor public for two reasons:

1. Spec specifically calls out a create method on Resource that accepts attributes. The ctor satisfied that nicely. Really Resource class is highly compliant with the spec.
2. You can new up a Resource and pass it to the AddResource method on ResourceBuilder. User is free to do this, if they want to:

   var builder = ResourceBuilder.CreateEmpty()
      .AddService("MyService")
      .AddResource(new Resource(new Dictionary<string, object> { ["Key1"] = "Value1" }))
      .AddResource(new Resource(new Dictionary<string, object> { ["Key2"] = "Value2" }));

If you still want to make internal though, fine with me.

Can I also remove builder.AddResource(Resource) as well? That'll ensure there is only way to create Resource - its through ResourceBuilder.

[CodeBlanch]

@cijothomas

Can I also remove builder.AddResource(Resource) as well? That'll ensure there is only way to create Resource - its through ResourceBuilder.

Check out ResourceBuilderExtensions.cs. All the extensions use AddResource to add things to the builder. The Build() call just loops through the added Resources and calls Merge on them. You could make AddResource internal (like AddDetector), but then extension authors wouldn't be able to extend the API without some kind of reflection. May or may not be an issue?

[cijothomas]

@cijothomas

Can I also remove builder.AddResource(Resource) as well? That'll ensure there is only way to create Resource - its through ResourceBuilder.

Check out ResourceBuilderExtensions.cs. All the extensions use AddResource to add things to the builder. The Build() call just loops through the added Resources and calls Merge on them. You could make AddResource internal (like AddDetector), but then extension authors wouldn't be able to extend the API without some kind of reflection. May or may not be an issue?

The extensibility for Resource would come through ResourceDetectors - we just need to wait for spec to finalize on that. (https://github.com/open-telemetry/oteps/blob/master/text/0111-auto-resource-detection.md)

But, until then, we can still do the below, right?

public static ResourceBuilder AddCijoResource(this ResourceBuilder resourceBuilder)
        {
            // var attributes = populate Cijo Resources;
            return ResourceBuilder.AddAttributes(attributes);
        }

[CodeBlanch]

@cijothomas

But, until then, we can still do the below, right?

Ya that would work fine, good call.

[codecov]

Codecov Report

Merging #1566 (d6dc645) into master (68adae6) will increase coverage by 0.05%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##           master    #1566      +/-   ##
==========================================
+ Coverage   81.00%   81.05%   +0.05%     
==========================================
  Files         237      237              
  Lines        6453     6449       -4     
==========================================
  Hits         5227     5227              
+ Misses       1226     1222       -4     

Impacted Files	Coverage Δ
...orter.OpenTelemetryProtocol/OtlpExporterOptions.cs	100.00% <ø> (ø)
...Telemetry/Trace/TracerProviderBuilderExtensions.cs	70.58% <ø> (ø)
...rc/OpenTelemetry/Trace/TracerProviderBuilderSdk.cs	87.03% <ø> (ø)
src/OpenTelemetry/Resources/ResourceBuilder.cs	90.47% <75.00%> (ø)
...try.Exporter.OpenTelemetryProtocol/OtlpExporter.cs	57.89% <100.00%> (-0.65%)	⬇️
src/OpenTelemetry/Resources/Resource.cs	93.33% <100.00%> (ø)
...lemetry/Internal/SelfDiagnosticsConfigRefresher.cs	21.68% <0.00%> (+3.61%)	⬆️