Supported multiple reporters in maven

### What's done:
- supported reporters to configure reporters in maven
- supported a default location for all reporters

It closes #1818

diktat-gradle-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/gradle/Utils.kt

@@ -2,8 +2,6 @@
  * Utilities for diktat gradle plugin
  */
 
-@file:Suppress("FILE_NAME_MATCH_CLASS", "MatchingDeclarationName")
-
 package com.saveourtool.diktat.plugin.gradle
 
 import org.gradle.api.Project

diktat-gradle-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/gradle/extension/DefaultReporter.kt

@@ -6,6 +6,7 @@
 
 package com.saveourtool.diktat.plugin.gradle.extension
 
+import com.saveourtool.diktat.api.DiktatReporterCreationArguments
 import com.saveourtool.diktat.api.DiktatReporterType
 import com.saveourtool.diktat.plugin.gradle.defaultReportLocation
 import org.gradle.api.Project
@@ -14,6 +15,8 @@ import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.model.ObjectFactory
 import org.gradle.api.provider.Provider
 import java.io.File
+import java.nio.file.Files
+import java.nio.file.Path
 import javax.inject.Inject
 
 /**
@@ -32,6 +35,12 @@ abstract class DefaultReporter @Inject constructor(
         .also { fileProperty ->
             fileProperty.convention(project.defaultReportLocation(extension = type.extension))
         }
+
+    override fun toCreationArguments(sourceRootDir: Path): DiktatReporterCreationArguments = DiktatReporterCreationArguments(
+        reporterType = type,
+        outputStream = output.map { file -> file.asFile.also { Files.createDirectories(it.parentFile.toPath()) }.outputStream() }.orNull,
+        sourceRootDir = sourceRootDir.takeIf { type == DiktatReporterType.SARIF },
+    )
 }
 
 /**

diktat-gradle-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/gradle/extension/Reporter.kt

@@ -1,7 +1,9 @@
 package com.saveourtool.diktat.plugin.gradle.extension
 
+import com.saveourtool.diktat.api.DiktatReporterCreationArguments
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.OutputFile
+import java.nio.file.Path
 
 /**
  * A base interface for reporter
@@ -12,4 +14,10 @@ interface Reporter {
      */
     @get:OutputFile
     val output: RegularFileProperty
+
+    /**
+     * @param sourceRootDir
+     * @return [DiktatReporterCreationArguments] to create this reporter
+     */
+    fun toCreationArguments(sourceRootDir: Path): DiktatReporterCreationArguments
 }

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/DiktatBaseMojo.kt

@@ -5,6 +5,11 @@ import com.saveourtool.diktat.DiktatRunnerArguments
 import com.saveourtool.diktat.api.DiktatReporterCreationArguments
 import com.saveourtool.diktat.api.DiktatReporterType
 import com.saveourtool.diktat.diktatRunnerFactory
+import com.saveourtool.diktat.plugin.maven.reporters.DefaultReporter
+import com.saveourtool.diktat.plugin.maven.reporters.GitHubActionsReporter
+import com.saveourtool.diktat.plugin.maven.reporters.PlainReporter
+import com.saveourtool.diktat.plugin.maven.reporters.Reporter
+import com.saveourtool.diktat.plugin.maven.reporters.Reporters
 import com.saveourtool.diktat.util.isKotlinCodeOrScript
 
 import org.apache.maven.plugin.AbstractMojo
@@ -33,17 +38,10 @@ abstract class DiktatBaseMojo : AbstractMojo() {
     var githubActions = false
 
     /**
-     * Type of the reporter to use
+     * The reporters to use
      */
-    @Parameter(property = "diktat.reporter")
-    var reporter = "plain"
-
-    /**
-     * Type of output
-     * Default: System.out
-     */
-    @Parameter(property = "diktat.output")
-    var output = ""
+    @Parameter
+    var reporters: Reporters? = null
 
     /**
      * Baseline file, containing a list of errors that will be ignored.
@@ -100,19 +98,23 @@ abstract class DiktatBaseMojo : AbstractMojo() {
                 if (excludes.isNotEmpty()) " and excluding $excludes" else ""
         )
 
-        val sourceRootDir = mavenProject.basedir.parentFile.toPath()
-        val reporterType = getReporterType()
-        val reporterArgs = DiktatReporterCreationArguments(
-            reporterType = reporterType,
-            outputStream = getReporterOutput(),
-            sourceRootDir = sourceRootDir.takeIf { reporterType == DiktatReporterType.SARIF },
-        )
+        val sourceRootDir = generateSequence(mavenProject) { it.parent }.last().basedir.toPath()
+        val reporters: List<Reporter> = (reporters?.all ?: listOf(PlainReporter()))
+            .let { all ->
+                if (githubActions && all.filterIsInstance<GitHubActionsReporter>().isEmpty()) {
+                    all + GitHubActionsReporter()
+                } else {
+                    all
+                }
+            }
+
+        val reporterArgsList = reporters.map { it.toCreationArguments(mavenProject, sourceRootDir) }
         val args = DiktatRunnerArguments(
             configInputStream = configFile.inputStream(),
             sourceRootDir = sourceRootDir,
             files = files(),
             baselineFile = baseline?.toPath(),
-            reporterArgsList = listOf(reporterArgs),
+            reporterArgsList = reporterArgsList,
         )
         val diktatRunner = diktatRunnerFactory(args)
         val errorCounter = runAction(
@@ -124,23 +126,6 @@ abstract class DiktatBaseMojo : AbstractMojo() {
         }
     }
 
-    private fun getReporterType(): DiktatReporterType = if (githubActions) {
-        DiktatReporterType.SARIF
-    } else {
-        DiktatReporterType.entries.firstOrNull { it.id.equals(reporter, ignoreCase = true) } ?: run {
-            log.warn("Reporter name ${this.reporter} was not specified or is invalid. Falling to 'plain' reporter")
-            DiktatReporterType.PLAIN
-        }
-    }
-
-    private fun getReporterOutput(): OutputStream? = if (output.isNotBlank()) {
-        FileOutputStream(this.output, false)
-    } else if (githubActions) {
-        FileOutputStream("${mavenProject.basedir}/${mavenProject.name}.sarif", false)
-    } else {
-        null
-    }
-
     /**
      * Function that searches diktat config file in maven project hierarchy.
      * If [diktatConfigFile] is absolute, it's path is used. If [diktatConfigFile] is relative, this method looks for it in all maven parent projects.

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/Utils.kt

@@ -0,0 +1,21 @@
+/**
+ * Utilities for diktat maven plugin
+ */
+
+package com.saveourtool.diktat.plugin.maven
+
+import com.saveourtool.diktat.api.DiktatReporterType
+import org.apache.maven.project.MavenProject
+import java.io.File
+
+/**
+ * @param reporterType
+ * @return default location of report with provided [reporterType]
+ */
+internal fun MavenProject.defaultReportLocation(
+    reporterType: DiktatReporterType,
+): File = basedir
+    .resolve(build.directory)
+    .resolve("reports")
+    .resolve("diktat")
+    .resolve("diktat.${reporterType.extension}")

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/reporters/DefaultReporter.kt

@@ -0,0 +1,79 @@
+/**
+ * All default reporters
+ */
+
+package com.saveourtool.diktat.plugin.maven.reporters
+
+import com.saveourtool.diktat.api.DiktatReporterCreationArguments
+import com.saveourtool.diktat.api.DiktatReporterType
+import com.saveourtool.diktat.plugin.maven.defaultReportLocation
+import org.apache.maven.plugins.annotations.Parameter
+import org.apache.maven.project.MavenProject
+import java.io.File
+import java.nio.file.Path
+
+/**
+ * A base interface for a default reporter
+ *
+ * @property type type of reporter
+ */
+abstract class DefaultReporter(
+    private val type: DiktatReporterType,
+) : Reporter {
+    /**
+     * Location for output
+     */
+    @Parameter
+    var output: File? = null
+
+    override fun getOutput(project: MavenProject): File? = output ?: project.defaultReportLocation(type)
+
+    override fun toCreationArguments(
+        project: MavenProject,
+        sourceRootDir: Path,
+    ): DiktatReporterCreationArguments = DiktatReporterCreationArguments(
+        reporterType = type,
+        outputStream = getOutputStream(project),
+        sourceRootDir = sourceRootDir.takeIf { type == DiktatReporterType.SARIF },
+    )
+}
+
+/**
+ * Plain reporter
+ */
+class PlainReporter : DefaultReporter(
+    type = DiktatReporterType.PLAIN,
+) {
+    /**
+     * Plain reporter prints to stdout by default
+     */
+    override fun getOutput(project: MavenProject): File? = output
+}
+
+/**
+ * JSON reporter
+ */
+class JsonReporter : DefaultReporter(
+    type = DiktatReporterType.JSON,
+)
+
+/**
+ * SARIF reporter
+ */
+class SarifReporter : DefaultReporter(
+    type = DiktatReporterType.SARIF,
+)
+
+/**
+ * Checkstyle reporter
+ */
+class CheckstyleReporter : DefaultReporter(
+    type = DiktatReporterType.CHECKSTYLE,
+)
+
+/**
+ * HTML reporter
+ */
+class HtmlReporter : DefaultReporter(
+    type = DiktatReporterType.HTML,
+)

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/reporters/GitHubActionsReporter.kt

@@ -0,0 +1,21 @@
+package com.saveourtool.diktat.plugin.maven.reporters
+
+import com.saveourtool.diktat.api.DiktatReporterCreationArguments
+import com.saveourtool.diktat.api.DiktatReporterType
+import com.saveourtool.diktat.plugin.maven.defaultReportLocation
+import org.apache.maven.project.MavenProject
+import java.io.File
+import java.nio.file.Path
+
+/**
+ * GitHub actions reporter
+ */
+class GitHubActionsReporter : Reporter {
+    override fun getOutput(project: MavenProject): File = project.defaultReportLocation(DiktatReporterType.SARIF)
+    override fun toCreationArguments(project: MavenProject, sourceRootDir: Path): DiktatReporterCreationArguments =
+        DiktatReporterCreationArguments(
+            reporterType = DiktatReporterType.SARIF,
+            outputStream = getOutputStream(project),
+            sourceRootDir = sourceRootDir,
+        )
+}

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/reporters/Reporter.kt

@@ -0,0 +1,32 @@
+package com.saveourtool.diktat.plugin.maven.reporters
+
+import com.saveourtool.diktat.api.DiktatReporterCreationArguments
+import org.apache.maven.project.MavenProject
+import java.io.File
+import java.io.OutputStream
+import java.nio.file.Files
+import java.nio.file.Path
+
+/**
+ * A base interface for reporter
+ */
+interface Reporter {
+    /**
+     * @param project
+     * @return location as a [File] for output or default value resolved by [project]
+     */
+    fun getOutput(project: MavenProject): File?
+
+    /**
+     * @param project
+     * @return location as an [OutputStream] for output or default value resolved by [project]
+     */
+    fun getOutputStream(project: MavenProject): OutputStream? = getOutput(project)?.also { Files.createDirectories(it.parentFile.toPath()) }?.outputStream()
+
+    /**
+     * @param project
+     * @param sourceRootDir
+     * @return [DiktatReporterCreationArguments] to create this reporter
+     */
+    fun toCreationArguments(project: MavenProject, sourceRootDir: Path): DiktatReporterCreationArguments
+}

diktat-maven-plugin/src/main/kotlin/com/saveourtool/diktat/plugin/maven/reporters/Reporters.kt

@@ -0,0 +1,57 @@
+package com.saveourtool.diktat.plugin.maven.reporters
+
+import org.apache.maven.plugins.annotations.Parameter
+
+/**
+ * Configuration for reporters
+ */
+class Reporters {
+    /**
+     * Configure *plain* reporter
+     */
+    @Parameter
+    var plain: PlainReporter? = null
+
+    /**
+     * Configure *json* reporter
+     */
+    @Parameter
+    var json: JsonReporter? = null
+
+    /**
+     * Configure *sarif* reporter
+     */
+    @Parameter
+    var sarif: SarifReporter? = null
+
+    /**
+     * Configure *sarif* reporter for GitHub actions
+     */
+    @Parameter
+    var gitHubActions: GitHubActionsReporter? = null
+
+    /**
+     * Configure *checkstyle* reporter
+     */
+    @Parameter
+    var checkstyle: CheckstyleReporter? = null
+
+    /**
+     * Configure *html* reporter
+     */
+    @Parameter
+    var html: HtmlReporter? = null
+
+    /**
+     * @return all configured reporters
+     */
+    val all: List<Reporter>
+        get() = listOfNotNull(
+            plain,
+            json,
+            sarif,
+            gitHubActions,
+            checkstyle,
+            html,
+        )
+}