Update metadata contract to be backcompatible with SPDX 2.2 parser (#918)

* Remove unnecessary parser errors which disallow syft SBOMs

* Add Spdx22Metadata back in to avoid major version bump

* update unit tests to reflect metadata class change

* revert to using spdx22metadata

---------

Co-authored-by: Sarah Oslund <sfoslund@microsoft.com>
Co-authored-by: ppandrate <ppandrate@microsoft.com>

Author: 3 people

src/Microsoft.Sbom.Contracts/Contracts/Spdx22Metadata.cs

@@ -0,0 +1,6 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+namespace Microsoft.Sbom.Contracts;
+
+public class Spdx22Metadata : SpdxMetadata { }

src/Microsoft.Sbom.Extensions/ISbomParser.cs

@@ -27,7 +27,7 @@ public interface ISbomParser
     /// </summary>
     /// <param name="stream"></param>
     /// <returns></returns>
-    SpdxMetadata GetMetadata();
+    Spdx22Metadata GetMetadata();
 
     /// <summary>
     /// This function is called by the sbom tool upon initialization to get all the

src/Microsoft.Sbom.Parsers.Spdx22SbomParser/Parser/SPDXParser.cs

@@ -172,14 +172,14 @@ internal SPDXParser(
         return null;
     }
 
-    public SpdxMetadata GetMetadata()
+    public Spdx22Metadata GetMetadata()
     {
         if (!this.parsingComplete)
         {
             throw new ParserException($"{nameof(this.GetMetadata)} can only be called after Parsing is complete to ensure that a whole object is returned.");
         }
 
-        var spdxMetadata = new SpdxMetadata();
+        var spdxMetadata = new Spdx22Metadata();
         foreach (var kvp in this.metadata)
         {
             switch (kvp.Key)

src/Microsoft.Sbom.Parsers.Spdx30SbomParser/Parser/SPDX30Parser.cs

@@ -35,7 +35,7 @@ public class SPDX30Parser : ISbomParser
 
     public ComplianceStandard? RequiredComplianceStandard;
     public IReadOnlyCollection<string>? EntitiesToEnforceComplianceStandardsFor;
-    public SpdxMetadata Metadata = new SpdxMetadata();
+    public Spdx22Metadata Metadata = new Spdx22Metadata();
     private readonly LargeJsonParser parser;
     private readonly IList<string> observedFieldNames = new List<string>();
     private readonly bool requiredFieldsCheck = true;
@@ -157,13 +157,14 @@ public SPDX30Parser(
         return null;
     }
 
-    public SpdxMetadata GetMetadata()
+    public Spdx22Metadata GetMetadata()
     {
         if (!this.parsingComplete)
         {
             throw new ParserException($"{nameof(this.GetMetadata)} can only be called after Parsing is complete to ensure that a whole object is returned.");
         }
 
+        // TODO: Eventually this return type should be changed to SpdxMetadata to be consistent with naming.
         return this.Metadata;
     }
 

test/Microsoft.Sbom.Parsers.Spdx22SbomParser.Tests/Parser/SbomFileParserTests.cs

@@ -5,6 +5,7 @@
 using System.IO;
 using System.Linq;
 using System.Text;
+using Microsoft.Sbom.Contracts;
 using Microsoft.Sbom.JsonAsynchronousNodeKit.Exceptions;
 using Microsoft.Sbom.Parser.Strings;
 using Microsoft.Sbom.Parsers.Spdx22SbomParser;
@@ -41,6 +42,7 @@ public void MetadataPopulates()
         var metadata = parser.GetMetadata();
 
         Assert.IsNotNull(metadata);
+        Assert.IsInstanceOfType(metadata, typeof(Spdx22Metadata));
         Assert.IsNotNull(metadata.CreationInfo);
         var expectedTime = DateTime.Parse("2023-05-11T00:24:54Z").ToUniversalTime();
         Assert.AreEqual(expectedTime, metadata.CreationInfo.Created);

test/Microsoft.Sbom.Parsers.Spdx30SbomParser.Tests/Parser/SbomMetadataParserTests.cs

@@ -5,6 +5,7 @@
 using System.IO;
 using System.Linq;
 using System.Text;
+using Microsoft.Sbom.Contracts;
 using Microsoft.Sbom.JsonAsynchronousNodeKit.Exceptions;
 using Microsoft.Sbom.Parser.JsonStrings;
 using Microsoft.Sbom.Parsers.Spdx30SbomParser;
@@ -27,6 +28,7 @@ public void MetadataPopulates()
         Assert.AreEqual(5, results.FormatEnforcedSPDX3Result.Graph.Count());
 
         var metadata = parser.GetMetadata();
+        Assert.IsInstanceOfType(metadata, typeof(Spdx22Metadata));
         Assert.IsNotNull(metadata);
         Assert.IsNotNull(metadata.DocumentNamespace);
         Assert.AreEqual("spdx-doc-name", metadata.Name);
@@ -49,6 +51,7 @@ public void MetadataEmpty()
         var results = this.Parse(parser);
 
         var metadata = parser.GetMetadata();
+        Assert.IsInstanceOfType(metadata, typeof(Spdx22Metadata));
         Assert.IsNotNull(metadata);
         Assert.IsNull(metadata.DocumentNamespace);
         Assert.IsNull(metadata.Name);

test/Microsoft.Sbom.Parsers.Spdx30SbomParser.Tests/Parser/SbomParserTestsBase.cs

@@ -243,9 +243,10 @@ public void ValidateSbomPackagesForNTIA(List<Element> elementsList)
     /// Sets metadata based on parsed SBOM elements.
     /// </summary>
     /// <param name="result"></param>
-    public SpdxMetadata SetMetadata(ParserResults result)
+    public Spdx22Metadata SetMetadata(ParserResults result)
     {
-        var metadata = new SpdxMetadata();
+        // TODO: Eventually this return type should be changed to SpdxMetadata to be consistent with naming.
+        var metadata = new Spdx22Metadata();
         var spdxDocumentElement = (SpdxDocument?)result.FormatEnforcedSPDX3Result.Graph.FirstOrDefault(element => element.Type == "SpdxDocument");
 
         if (spdxDocumentElement == null)