Update metadata contract to be backcompatible with SPDX 2.2 parser

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.Contracts/Contracts/Spdx30Metadata.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 Spdx30Metadata : SpdxMetadata { }

src/Microsoft.Sbom.Contracts/Contracts/SpdxMetadata.cs

@@ -9,7 +9,7 @@ namespace Microsoft.Sbom.Contracts;
 /// <summary>
 /// The object representation of all the metadata in an SPDX document.
 /// </summary>
-public class SpdxMetadata
+public abstract class SpdxMetadata
 {
     /// <summary>
     /// The version of the SPDX specification used in this document.

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

@@ -179,7 +179,7 @@ public SpdxMetadata GetMetadata()
             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.Spdx22SbomParser/Utils/SPDXToSbomFormatConverterExtensions.cs

@@ -26,10 +26,6 @@ public static class SPDXToSbomFormatConverterExtensions
     public static SbomFile ToSbomFile(this SPDXFile spdxFile)
     {
         var checksums = spdxFile.FileChecksums?.Select(c => c.ToSbomChecksum());
-        if (!checksums.Any() || checksums.All(c => c.Algorithm != AlgorithmName.SHA256))
-        {
-            throw new ParserException("File hash is missing a SHA256 value");
-        }
 
         return new SbomFile
         {
@@ -49,12 +45,6 @@ public static SbomFile ToSbomFile(this SPDXFile spdxFile)
     /// <returns></returns>
     public static SbomPackage ToSbomPackage(this SPDXPackage spdxPackage)
     {
-        if (spdxPackage.FilesAnalyzed &&
-            (spdxPackage.LicenseInfoFromFiles == null || !spdxPackage.LicenseInfoFromFiles.Any()))
-        {
-            throw new ParserException("Package license list was empty.");
-        }
-
         if (spdxPackage.PackageVerificationCode is not null
             && string.IsNullOrEmpty(spdxPackage.PackageVerificationCode.PackageVerificationCodeValue))
         {

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 SpdxMetadata Metadata = new Spdx30Metadata();
     private readonly LargeJsonParser parser;
     private readonly IList<string> observedFieldNames = new List<string>();
     private readonly bool requiredFieldsCheck = true;

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(Spdx30Metadata));
         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(Spdx30Metadata));
         Assert.IsNotNull(metadata);
         Assert.IsNull(metadata.DocumentNamespace);
         Assert.IsNull(metadata.Name);

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

@@ -245,7 +245,7 @@ public void ValidateSbomPackagesForNTIA(List<Element> elementsList)
     /// <param name="result"></param>
     public SpdxMetadata SetMetadata(ParserResults result)
     {
-        var metadata = new SpdxMetadata();
+        var metadata = new Spdx30Metadata();
         var spdxDocumentElement = (SpdxDocument?)result.FormatEnforcedSPDX3Result.Graph.FirstOrDefault(element => element.Type == "SpdxDocument");
 
         if (spdxDocumentElement == null)