refactor(scanner): Extract VCSPath filtering functions

Scanners generally do not consider the VCSPath when performing an
ORT scan on a repository, as they scan the entire repository and
its dependencies. The resulting scan data is cached for reuse
across multiple scans.

When reusing cached scan results for ORT scans with a specified
VCSPath, where only a subset of the repository is scanned, it
is necessary to filter out extraneous scan results. Helper
functions already exist to handle this filtering.

This refactoring extracts these helper functions and allows
ORT Server to use them.
See: eclipse-apoapsis/ort-server#1358

Signed-off-by: Wolfgang Klenk <[email protected]>

Author: wkl3nk

scanner/src/main/kotlin/Scanner.kt

@@ -39,9 +39,7 @@ import org.ossreviewtoolkit.model.KnownProvenance
 import org.ossreviewtoolkit.model.OrtResult
 import org.ossreviewtoolkit.model.Package
 import org.ossreviewtoolkit.model.PackageType
-import org.ossreviewtoolkit.model.Provenance
 import org.ossreviewtoolkit.model.ProvenanceResolutionResult
-import org.ossreviewtoolkit.model.RepositoryProvenance
 import org.ossreviewtoolkit.model.ScanResult
 import org.ossreviewtoolkit.model.ScanSummary
 import org.ossreviewtoolkit.model.ScannerRun
@@ -54,14 +52,16 @@ import org.ossreviewtoolkit.model.createAndLogIssue
 import org.ossreviewtoolkit.model.mapLicense
 import org.ossreviewtoolkit.model.utils.FileArchiver
 import org.ossreviewtoolkit.model.utils.ProvenanceFileStorage
-import org.ossreviewtoolkit.model.utils.getKnownProvenancesWithoutVcsPath
 import org.ossreviewtoolkit.model.utils.vcsPath
 import org.ossreviewtoolkit.scanner.provenance.NestedProvenance
 import org.ossreviewtoolkit.scanner.provenance.NestedProvenanceResolver
 import org.ossreviewtoolkit.scanner.provenance.NestedProvenanceScanResult
 import org.ossreviewtoolkit.scanner.provenance.PackageProvenanceResolver
 import org.ossreviewtoolkit.scanner.provenance.ProvenanceDownloader
 import org.ossreviewtoolkit.scanner.utils.FileListResolver
+import org.ossreviewtoolkit.scanner.utils.alignRevisions
+import org.ossreviewtoolkit.scanner.utils.filterScanResultsByVcsPaths
+import org.ossreviewtoolkit.scanner.utils.getVcsPathsForProvenances
 import org.ossreviewtoolkit.utils.common.CommandLineTool
 import org.ossreviewtoolkit.utils.common.collectMessages
 import org.ossreviewtoolkit.utils.common.safeDeleteRecursively
@@ -190,25 +190,9 @@ class Scanner(
             ).filterByVcsPath()
         }
 
-        val vcsPathsForProvenances = buildMap<KnownProvenance, MutableSet<String>> {
-            provenances.forEach { provenance ->
-                val packageVcsPath = provenance.packageProvenance?.vcsPath.orEmpty()
+        val vcsPathsForProvenances = getVcsPathsForProvenances(provenances)
 
-                provenance.getKnownProvenancesWithoutVcsPath().forEach { (repositoryPath, provenance) ->
-                    getVcsPathForRepositoryOrNull(packageVcsPath, repositoryPath)?.let { vcsPath ->
-                        getOrPut(provenance) { mutableSetOf() } += vcsPath
-                    }
-                }
-            }
-        }
-
-        val scanResults = controller.getAllScanResults().map { scanResult ->
-            scanResult.copy(provenance = scanResult.provenance.alignRevisions())
-        }.mapNotNullTo(mutableSetOf()) { scanResult ->
-            vcsPathsForProvenances[scanResult.provenance]?.let {
-                scanResult.copy(summary = scanResult.summary.filterByPaths(it))
-            }
-        }
+        val filteredScanResults = filterScanResultsByVcsPaths(controller.getAllScanResults(), vcsPathsForProvenances)
 
         val files = controller.getAllFileLists().mapTo(mutableSetOf()) { (provenance, fileList) ->
             FileList(
@@ -229,7 +213,7 @@ class Scanner(
         return ScannerRun.EMPTY.copy(
             config = scannerConfig,
             provenances = provenances,
-            scanResults = scanResults,
+            scanResults = filteredScanResults,
             files = files,
             scanners = scanners
         )
@@ -782,13 +766,6 @@ fun ScanResult.toNestedProvenanceScanResult(nestedProvenance: NestedProvenance):
     return NestedProvenanceScanResult(nestedProvenance, scanResultsByProvenance)
 }
 
-fun <T : Provenance> T.alignRevisions(): Provenance =
-    if (this is RepositoryProvenance) {
-        copy(vcsInfo = vcsInfo.copy(revision = resolvedRevision))
-    } else {
-        this
-    }
-
 private fun ScanController.getSubRepositories(id: Identifier): Map<String, VcsInfo> {
     val nestedProvenance = getNestedProvenance(id) ?: return emptyMap()
 
@@ -802,21 +779,6 @@ private fun ProvenanceResolutionResult.filterByVcsPath(): ProvenanceResolutionRe
         }
     )
 
-/**
- * Return the VCS path applicable to a (sub-) repository which appears under [repositoryPath] in the source tree of
- * a package residing in [vcsPath], or null if the subtrees for [repositoryPath] and [vcsPath] are disjoint.
- */
-private fun getVcsPathForRepositoryOrNull(vcsPath: String, repositoryPath: String): String? {
-    val repoPathFile = File(repositoryPath)
-    val vcsPathFile = File(vcsPath)
-
-    return if (repoPathFile.startsWith(vcsPathFile)) {
-        ""
-    } else {
-        runCatching { vcsPathFile.toRelativeString(repoPathFile) }.getOrNull()
-    }
-}
-
 private fun FileList.filterByVcsPaths(paths: Collection<String>): FileList =
     if (paths.any { it.isBlank() }) {
         this

scanner/src/main/kotlin/utils/Utils.kt

@@ -19,8 +19,15 @@
 
 package org.ossreviewtoolkit.scanner.utils
 
+import java.io.File
+
+import org.ossreviewtoolkit.model.KnownProvenance
 import org.ossreviewtoolkit.model.Provenance
+import org.ossreviewtoolkit.model.ProvenanceResolutionResult
 import org.ossreviewtoolkit.model.RepositoryProvenance
+import org.ossreviewtoolkit.model.ScanResult
+import org.ossreviewtoolkit.model.utils.getKnownProvenancesWithoutVcsPath
+import org.ossreviewtoolkit.model.utils.vcsPath
 import org.ossreviewtoolkit.scanner.ScanStorageException
 
 /**
@@ -31,3 +38,55 @@ internal fun requireEmptyVcsPath(provenance: Provenance) {
         throw ScanStorageException("Repository provenances with a non-empty VCS path are not supported.")
     }
 }
+
+/**
+ * Return a map of VCS paths for each [KnownProvenance] contained in [provenances].
+ */
+fun getVcsPathsForProvenances(provenances: Set<ProvenanceResolutionResult>) =
+    buildMap<KnownProvenance, MutableSet<String>> {
+        provenances.forEach { provenance ->
+            val packageVcsPath = provenance.packageProvenance?.vcsPath.orEmpty()
+
+            provenance.getKnownProvenancesWithoutVcsPath().forEach { (repositoryPath, provenance) ->
+                getVcsPathForRepositoryOrNull(packageVcsPath, repositoryPath)?.let { vcsPath ->
+                    getOrPut(provenance) { mutableSetOf() } += vcsPath
+                }
+            }
+        }
+    }
+
+/**
+ * Filter [ScanResult]s by the VCS paths of the [KnownProvenance]s contained in [vcsPathsForProvenances].
+ */
+fun filterScanResultsByVcsPaths(
+    allScanResults: List<ScanResult>,
+    vcsPathsForProvenances: Map<KnownProvenance, MutableSet<String>>
+) = allScanResults.map { scanResult ->
+    scanResult.copy(provenance = scanResult.provenance.alignRevisions())
+}.mapNotNullTo(mutableSetOf()) { scanResult ->
+    vcsPathsForProvenances[scanResult.provenance]?.let {
+        scanResult.copy(summary = scanResult.summary.filterByPaths(it))
+    }
+}
+
+/**
+ * Return the VCS path applicable to a (sub-) repository which appears under [repositoryPath] in the source tree of
+ * a package residing in [vcsPath], or null if the subtrees for [repositoryPath] and [vcsPath] are disjoint.
+ */
+private fun getVcsPathForRepositoryOrNull(vcsPath: String, repositoryPath: String): String? {
+    val repoPathFile = File(repositoryPath)
+    val vcsPathFile = File(vcsPath)
+
+    return if (repoPathFile.startsWith(vcsPathFile)) {
+        ""
+    } else {
+        runCatching { vcsPathFile.toRelativeString(repoPathFile) }.getOrNull()
+    }
+}
+
+internal fun <T : Provenance> T.alignRevisions(): Provenance =
+    if (this is RepositoryProvenance) {
+        copy(vcsInfo = vcsInfo.copy(revision = resolvedRevision))
+    } else {
+        this
+    }