feat(model): Extends the model to capture Snippets from snippet scanners

Snippet scanners such as ScanOSS [1] and FossID [2] can identify code
snippets potentially coming from a third party source. To do so, they
scan the Internet for source code and build a Knowledge Base (KB). Then,
the source code to check for snippets is scanned and compared against
this KB.

Snippet Findings are not License nor Copyright findings as a human
operator needs to review them and either accept or flag them as
false positives.

Therefore, this commit adds a new property ORT data model in the
`ScanSummary` to carry these snippet findings.
This model has been created by comparing the results from FossID and
ScanOSS and trying to find a common abstraction. This is currently the
minimal model required to handle snippets.
Further properties such as matched lines (present in both results) will
be added in the future.

Blackduck [3] is another scanner considered for integration in ORT [4]
which supports snippets. However since it does not deliver snippets
through its API, it was not considered when designing the snippet Data
model for ORT.

Fixes: oss-review-toolkit#3265.

[1]: https://www.scanoss.com/
[2]: https://fossid.com/
[3]: https://www.synopsys.com/software-integrity/security-testing/software-composition-analysis.html
[4]: oss-review-toolkit#4632

Signed-off-by: Nicolas Nobelis <nicolas.nobelis@bosch.io>

model/src/main/kotlin/ScanSummary.kt

@@ -29,6 +29,7 @@ import java.util.SortedSet
 
 import org.ossreviewtoolkit.model.config.LicenseFilePatterns
 import org.ossreviewtoolkit.model.utils.RootLicenseMatcher
+import org.ossreviewtoolkit.model.utils.SnippetFinding
 import org.ossreviewtoolkit.utils.common.FileMatcher
 import org.ossreviewtoolkit.utils.spdx.SpdxExpression
 
@@ -66,6 +67,12 @@ data class ScanSummary(
     @JsonProperty("copyrights")
     val copyrightFindings: SortedSet<CopyrightFinding>,
 
+    /**
+     * The detected snippet findings, aggregated per file of the source code repository being scanned.
+     */
+    @JsonProperty("snippets")
+    val snippetFindings: Map<String, Set<SnippetFinding>> = emptyMap(),
+
     /**
      * The list of issues that occurred during the scan. This property is not serialized if the list is empty to reduce
      * the size of the result file. If there are no issues at all, [ScannerRun.hasIssues] already contains that
@@ -84,7 +91,8 @@ data class ScanSummary(
             endTime = Instant.EPOCH,
             packageVerificationCode = "",
             licenseFindings = sortedSetOf(),
-            copyrightFindings = sortedSetOf()
+            copyrightFindings = sortedSetOf(),
+            snippetFindings = emptyMap()
         )
     }
 

model/src/main/kotlin/utils/SnippetFinding.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2023 The ORT Project Authors (see <https://github.com/oss-review-toolkit/ort/blob/main/NOTICE>)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * License-Filename: LICENSE
+ */
+
+package org.ossreviewtoolkit.model.utils
+
+import org.ossreviewtoolkit.utils.spdx.SpdxExpression
+
+/**
+ * A class representing a snippet finding. A snippet finding is a code snippet of [artifact] and [version], with the
+ * following [licenses], matching the code being scanned.
+ * It is meant to be reviewed by an operator as it could be a false positive.
+ */
+data class SnippetFinding(
+    /**
+     * The author/vendor of the component the code snippet is commit from.
+     */
+    val author: String,
+    /**
+     * The artifact name of the component the code snippet is commit from.
+     */
+    val artifact: String,
+    /**
+     * The version of the component the code snippet is commit from.
+     */
+    val version: String,
+    /**
+     * The license(s) of the component the code snippet is commit from.
+     */
+    val licenses: Set<SpdxExpression>,
+    /**
+     * The matching score between the code being scanned and the code snippet. This is scanner specific (e.g. for
+     * ScanOSS this is a percentage).
+     */
+    val score: Float
+) : Comparable<SnippetFinding> {
+    companion object {
+        private val COMPARATOR =
+            compareBy<SnippetFinding>(
+                { it.author },
+                { it.artifact },
+                { it.version },
+                { it.licenses.toString() }
+            ).thenByDescending { it.score }
+    }
+
+    override fun compareTo(other: SnippetFinding) = COMPARATOR.compare(this, other)
+}

scanner/src/funTest/assets/dummy-expected-output-for-analyzer-result.yml

@@ -237,6 +237,7 @@ scanner:
         package_verification_code: ""
         licenses: []
         copyrights: []
+        snippets: {}
         issues:
         - timestamp: "1970-01-01T00:00:00Z"
           source: "scanner"
@@ -282,6 +283,7 @@ scanner:
             start_line: -1
             end_line: -1
         copyrights: []
+        snippets: {}
     Maven:org.apache.commons:commons-lang3:3.5:
     - provenance:
         source_artifact:
@@ -309,6 +311,7 @@ scanner:
             start_line: -1
             end_line: -1
         copyrights: []
+        snippets: {}
     Maven:org.apache.commons:commons-text:1.1:
     - provenance:
         source_artifact:
@@ -336,6 +339,7 @@ scanner:
             start_line: -1
             end_line: -1
         copyrights: []
+        snippets: {}
     Maven:org.hamcrest:hamcrest-core:1.3:
     - provenance:
         source_artifact:
@@ -363,6 +367,7 @@ scanner:
             start_line: -1
             end_line: -1
         copyrights: []
+        snippets: {}
   storage_stats:
     num_reads: 0
     num_hits: 0

scanner/src/main/kotlin/scanners/fossid/FossId.kt

@@ -214,7 +214,7 @@ class FossId internal constructor(
         endTime: Instant = Instant.now(),
         issue: Issue
     ) = ScanSummary(
-        startTime, endTime, "", sortedSetOf(), sortedSetOf(), listOf(issue)
+        startTime, endTime, "", sortedSetOf(), sortedSetOf(), issues = listOf(issue)
     )
 
     override fun scanPackage(pkg: Package, context: ScanContext): ScanResult {