feat(vcs): Add Git-specific configuration options for submodule handling

wkl3nk · wkl3nk · commit 1cf9421f688d · 2024-10-21T17:17:33.000+02:00
For large repositories with many layers of nested Git submodules, the
 download process can be very time-consuming and often results in
 duplicate projects in the tree of nested submodules.
 This feature introduces configuration options to limit the recursive
 checkout of nested Git submodules to the first layer, optimizing
 performance and reducing redundancy. Additionally, it also allows to
 limit the depth of commit history to fetch when downloading
 the projects.

Signed-off-by: Wolfgang Klenk &lt;wolfgang.klenk2@bosch.com&gt;
diff --git a/plugins/version-control-systems/git/src/main/kotlin/Git.kt b/plugins/version-control-systems/git/src/main/kotlin/Git.kt
@@ -48,6 +48,9 @@ import org.ossreviewtoolkit.downloader.VersionControlSystem
 import org.ossreviewtoolkit.downloader.WorkingTree
 import org.ossreviewtoolkit.model.VcsInfo
 import org.ossreviewtoolkit.model.VcsType
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.Companion.getOrDefault
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.HISTORY_DEPTH
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.UPDATE_NESTED_SUBMODULES
 import org.ossreviewtoolkit.utils.common.CommandLineTool
 import org.ossreviewtoolkit.utils.common.Options
 import org.ossreviewtoolkit.utils.common.Os
@@ -60,14 +63,50 @@ import org.ossreviewtoolkit.utils.ort.showStackTrace
 import org.semver4j.RangesList
 import org.semver4j.RangesListFactory
 
-// TODO: Make this configurable.
-const val GIT_HISTORY_DEPTH = 50
-
 // Replace prefixes of Git submodule repository URLs.
 private val REPOSITORY_URL_PREFIX_REPLACEMENTS = listOf(
     "git://" to "https://"
 )
 
+enum class OptionKey(val key: String, val defaultValue: String, val deprecated: Boolean = false) {
+    // Git-specific configuration option for the depth of commit history to fetch
+    HISTORY_DEPTH("historyDepth", "50"),
+
+    // Git-specific configuration option to define if nested submodules should be updated, or if only the
+    // submodules on the top-level should be initialized, updated, and cloned.
+    UPDATE_NESTED_SUBMODULES("updateNestedSubmodules", "true"),
+
+    // Example for deprecating a configuration option
+    DO_NOT_USE("doNotUse", "some-value", deprecated = true);
+
+    companion object {
+        private val map = entries.associateBy(OptionKey::key)
+        private val validKeys: Set<String> get() = map.keys
+
+        fun validate(options: Options): OptionsValidationResult {
+            val unknownKeys = options.keys - OptionKey.validKeys
+            val deprecatedKeys = entries.filter { it.deprecated }.map { it.key }.toSet()
+            val usedDeprecatedKeys = options.keys.intersect(deprecatedKeys)
+
+            return OptionsValidationResult(
+                isSuccess = unknownKeys.isEmpty(),
+                errors = unknownKeys.map { "Unknown Git-specific configuration key: '$it'" },
+                warnings = usedDeprecatedKeys.map {
+                    "Git-specific configuration key '$it' is deprecated and may be removed in future versions."
+                }
+            )
+        }
+
+        fun getOrDefault(options: Options, key: OptionKey): String = options[key.key] ?: key.defaultValue
+    }
+}
+
+data class OptionsValidationResult(
+    val isSuccess: Boolean,
+    val errors: List<String> = emptyList(),
+    val warnings: List<String> = emptyList()
+)
+
 object GitCommand : CommandLineTool {
     private val versionRegex = Regex("[Gg]it [Vv]ersion (?<version>[\\d.a-z-]+)(\\s.+)?")
 
@@ -178,9 +217,24 @@ class Git : VersionControlSystem(GitCommand) {
             Git(this).use { git ->
                 logger.info { "Updating working tree from ${workingTree.getRemoteUrl()}." }
 
-                updateWorkingTreeWithoutSubmodules(workingTree, git, revision).mapCatching {
+                val optionsValidationResult = OptionKey.validate(options)
+                optionsValidationResult.warnings.forEach { logger.warn { it } }
+                optionsValidationResult.warnings.forEach { logger.error { it } }
+                require(optionsValidationResult.isSuccess) {
+                    optionsValidationResult.errors.joinToString()
+                }
+
+                val historyDepth = getOrDefault(options, HISTORY_DEPTH).toInt()
+                updateWorkingTreeWithoutSubmodules(workingTree, git, revision, historyDepth).mapCatching {
                     // In case this throws the exception gets encapsulated as a failure.
-                    if (recursive) updateSubmodules(workingTree)
+                    if (recursive) {
+                        val updateNestedSubmodules = getOrDefault(options, UPDATE_NESTED_SUBMODULES).toBoolean()
+                        updateSubmodules(
+                            workingTree,
+                            recursive = updateNestedSubmodules,
+                            historyDepth = historyDepth
+                        )
+                    }
 
                     revision
                 }
@@ -190,12 +244,13 @@ class Git : VersionControlSystem(GitCommand) {
     private fun updateWorkingTreeWithoutSubmodules(
         workingTree: WorkingTree,
         git: Git,
-        revision: String
+        revision: String,
+        historyDepth: Int
     ): Result<String> =
         runCatching {
-            logger.info { "Trying to fetch only revision '$revision' with depth limited to $GIT_HISTORY_DEPTH." }
+            logger.info { "Trying to fetch only revision '$revision' with depth limited to $historyDepth." }
 
-            val fetch = git.fetch().setDepth(GIT_HISTORY_DEPTH)
+            val fetch = git.fetch().setDepth(historyDepth)
 
             // See https://git-scm.com/docs/gitrevisions#_specifying_revisions for how Git resolves ambiguous
             // names. In particular, tag names have higher precedence than branch names.
@@ -213,13 +268,13 @@ class Git : VersionControlSystem(GitCommand) {
             it.showStackTrace()
 
             logger.info { "Could not fetch only revision '$revision': ${it.collectMessages()}" }
-            logger.info { "Falling back to fetching all refs with depth limited to $GIT_HISTORY_DEPTH." }
+            logger.info { "Falling back to fetching all refs with depth limited to $historyDepth." }
 
-            git.fetch().setDepth(GIT_HISTORY_DEPTH).setTagOpt(TagOpt.FETCH_TAGS).call()
+            git.fetch().setDepth(historyDepth).setTagOpt(TagOpt.FETCH_TAGS).call()
         }.recoverCatching {
             it.showStackTrace()
 
-            logger.info { "Could not fetch with only a depth of $GIT_HISTORY_DEPTH: ${it.collectMessages()}" }
+            logger.info { "Could not fetch with only a depth of $historyDepth: ${it.collectMessages()}" }
             logger.info { "Falling back to fetch everything including tags." }
 
             git.fetch().setUnshallow(true).setTagOpt(TagOpt.FETCH_TAGS).call()
@@ -274,7 +329,14 @@ class Git : VersionControlSystem(GitCommand) {
             revision
         }
 
-    private fun updateSubmodules(workingTree: WorkingTree) {
+    /**
+     *  Initialize, update, and clone all the submodules in a working tree.
+     *
+     *  If [recursive] is set to true, then the operations are not only performed on the
+     *  submodules in the top-level of the working tree, but also on the submodules of the submodules, and so on.
+     *  If [recursive] is set to false, only the submodules on the top-level are initialized, updated, and cloned.
+     */
+    private fun updateSubmodules(workingTree: WorkingTree, recursive: Boolean, historyDepth: Int) {
         if (!workingTree.getRootPath().resolve(".gitmodules").isFile) return
 
         val insteadOf = REPOSITORY_URL_PREFIX_REPLACEMENTS.map { (prefix, replacement) ->
@@ -283,14 +345,27 @@ class Git : VersionControlSystem(GitCommand) {
 
         runCatching {
             // TODO: Migrate this to JGit once https://bugs.eclipse.org/bugs/show_bug.cgi?id=580731 is implemented.
-            workingTree.runGit("submodule", "update", "--init", "--recursive", "--depth", "$GIT_HISTORY_DEPTH")
+            val updateArgs = mutableListOf("submodule", "update", "--init", "--depth", "$historyDepth").apply {
+                if (recursive) { add("--recursive") }
+            }
+
+            workingTree.runGit(*updateArgs.toTypedArray())
 
             insteadOf.forEach {
-                workingTree.runGit("submodule", "foreach", "--recursive", "git config $it")
+                val foreachArgs = mutableListOf("submodule", "foreach").apply {
+                    if (recursive) { add("--recursive") }
+                    add("git config $it")
+                }
+
+                workingTree.runGit(*foreachArgs.toTypedArray())
             }
         }.recover {
             // As Git's dumb HTTP transport does not support shallow capabilities, also try to not limit the depth.
-            workingTree.runGit("submodule", "update", "--recursive")
+            val fallbackArgs = mutableListOf("submodule", "update").apply {
+                if (recursive) { add("--recursive") }
+            }
+
+            workingTree.runGit(*fallbackArgs.toTypedArray())
         }
     }
 
diff --git a/plugins/version-control-systems/git/src/test/kotlin/GitTest.kt b/plugins/version-control-systems/git/src/test/kotlin/GitTest.kt
@@ -42,6 +42,10 @@ import org.eclipse.jgit.transport.CredentialItem
 import org.eclipse.jgit.transport.CredentialsProvider
 import org.eclipse.jgit.transport.URIish
 
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.Companion.getOrDefault
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.HISTORY_DEPTH
+import org.ossreviewtoolkit.plugins.versioncontrolsystems.git.OptionKey.UPDATE_NESTED_SUBMODULES
+import org.ossreviewtoolkit.utils.common.Options
 import org.ossreviewtoolkit.utils.ort.requestPasswordAuthentication
 
 class GitTest : WordSpec({
@@ -151,6 +155,86 @@ class GitTest : WordSpec({
             credentialProvider.isInteractive shouldBe false
         }
     }
+
+    "The validation of git-specific configuration options" should {
+        "succeed if valid configuration options are provided" {
+            val options: Options = mapOf(
+                "historyDepth" to "1",
+                "updateNestedSubmodules" to "false"
+            )
+
+            val result = OptionKey.validate(options)
+
+            result.isSuccess shouldBe true
+            result.errors shouldBe emptyList()
+            result.warnings shouldBe emptyList()
+
+            val historyDepth: Int = getOrDefault(options, HISTORY_DEPTH).toInt()
+            historyDepth shouldBe 1
+
+            val updateNestedSubmodules: Boolean = getOrDefault(options, UPDATE_NESTED_SUBMODULES).toBoolean()
+            updateNestedSubmodules shouldBe false
+        }
+
+        "fail if invalid configuration options are provided" {
+            val options: Options = mapOf(
+                "historyDepth" to "1",
+                "updateNestedSubmodules" to "false",
+                "invalidOption" to "value"
+            )
+
+            val result = OptionKey.validate(options)
+
+            result.isSuccess shouldBe false
+            result.errors.count() shouldBe 1
+            result.warnings shouldBe emptyList()
+        }
+
+        "return deprecated warning for deprecated configuration options" {
+            val options: Options = mapOf(
+                "historyDepth" to "1",
+                "updateNestedSubmodules" to "false",
+                "doNotUse" to "true"
+            )
+
+            val result = OptionKey.validate(options)
+
+            result.isSuccess shouldBe true
+            result.errors shouldBe emptyList()
+            result.warnings.count() shouldBe 1
+
+            val historyDepth: Int = getOrDefault(options, HISTORY_DEPTH).toInt()
+            historyDepth shouldBe 1
+
+            val updateNestedSubmodules: Boolean = getOrDefault(options, UPDATE_NESTED_SUBMODULES).toBoolean()
+            updateNestedSubmodules shouldBe false
+        }
+    }
+
+    "The helper for getting configuration options" should {
+        "return the correct values if the options are set" {
+            val options: Options = mapOf(
+                "historyDepth" to "1",
+                "updateNestedSubmodules" to "false"
+            )
+
+            val historyDepth: Int = getOrDefault(options, HISTORY_DEPTH).toInt()
+            historyDepth shouldBe 1
+
+            val updateNestedSubmodules: Boolean = getOrDefault(options, UPDATE_NESTED_SUBMODULES).toBoolean()
+            updateNestedSubmodules shouldBe false
+        }
+
+        "return the default value if the option is not set" {
+            val options: Options = emptyMap()
+
+            val historyDepth: Int = getOrDefault(options, HISTORY_DEPTH).toInt()
+            historyDepth shouldBe 50
+
+            val updateNestedSubmodules: Boolean = getOrDefault(options, UPDATE_NESTED_SUBMODULES).toBoolean()
+            updateNestedSubmodules shouldBe true
+        }
+    }
 })
 
 private val TestUri = URIish(URI.create("https://www.example.org:8080/foo").toURL())
