Fix #118: Don't print stacktrace on SQL syntax error.

src/main/kotlin/cz/dynawest/csvcruncher/Cruncher.kt

@@ -210,7 +210,7 @@ class Cruncher(private val options: Options) {
                     dirToCreate.mkdirs()
 
                     // Get the columns info: Perform the SQL, LIMIT 1.
-                    val columnsDef: Map<String, String> = dbHelper.extractColumnsInfoFrom1LineSelect(sql)
+                    val columnsDef: Map<String, String> = dbHelper.extractColumnsInfoFrom1LineSelect(sql, export.sqlQuery)
                     output.columnNamesAndTypes = columnsDef
 
 

src/main/kotlin/cz/dynawest/csvcruncher/HsqlDbHelper.kt

@@ -88,7 +88,7 @@ class HsqlDbHelper(val jdbcConn: Connection) {
      * Get the columns info: Perform the SQL, LIMIT 1.
      */
     @Throws(SQLException::class)
-    fun extractColumnsInfoFrom1LineSelect(sql: String): Map<String, String> {
+    fun extractColumnsInfoFrom1LineSelect(sql: String, userSql: String?): Map<String, String> {
 
         val sql = setOrReplaceLimit(sql, "LIMIT 1")
 
@@ -97,14 +97,30 @@ class HsqlDbHelper(val jdbcConn: Connection) {
             jdbcConn.prepareStatement(sql)
         }
         catch (ex: SQLSyntaxErrorException) {
+            // TBD: This would be nice to refactor for wherever SQL is executed.
+
+            val isWholeSqlInExMsg = ex.message?.contains("[$sql]") ?: false
+            val isSqlSameAsUserSql = sql == userSql
+
             if (ex.message!!.contains("unexpected token:")) {
-                throw SqlSyntaxCruncherException("""
-                |    The SQL contains syntax error:
-                |    ${ex.message}
-                |    $sql
-                |    This may be your SQL error or caused by alteration by CsvCruncher. 
-                |    See https://github.com/OndraZizka/csv-cruncher/issues for known bugs.
-                |    """.trimMargin())
+                var msg = """
+                    |    The SQL contains syntax error:
+                    |    ${ex.message}
+                """
+
+                if (!isWholeSqlInExMsg || !isSqlSameAsUserSql)
+                    msg += "|    Export's SQL: $sql\n"
+
+                if (isSqlSameAsUserSql)
+                    msg += "|    This is likely an error in your SQL. Please refer to HSQLDB SQL syntax: https://www.hsqldb.org/doc/guide/dataaccess-chapt.html#dac_sql_select_statement"
+                else
+                    msg += """
+                        |    This may be your SQL error or caused by alteration by CsvCruncher. 
+                        |    Check HSQLDB SQL syntax: https://www.hsqldb.org/doc/guide/dataaccess-chapt.html#dac_sql_select_statement
+                        |    See https://github.com/OndraZizka/csv-cruncher/issues for known bugs.
+                        |    """
+
+                throw SqlSyntaxCruncherException(msg.trimMargin())
             }
             if (ex.message!!.contains("object not found:")) {
                 throw throwHintForObjectNotFound(ex, this, sql)

src/main/kotlin/cz/dynawest/csvcruncher/app/App.kt

@@ -2,6 +2,8 @@ package cz.dynawest.csvcruncher.app
 
 import ch.qos.logback.classic.Level
 import cz.dynawest.csvcruncher.Cruncher
+import cz.dynawest.csvcruncher.CsvCruncherException
+import cz.dynawest.csvcruncher.SqlSyntaxCruncherException
 import cz.dynawest.csvcruncher.util.logger
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
@@ -31,9 +33,25 @@ object App {
         try {
             mainNoExit(args)
         }
-        catch (ex: IllegalArgumentException) {
-            println("" + ex.message)
-            System.exit(1)
+        catch (ex: Exception) {
+            val exitCode = when (ex) {
+                // Known app errors, or user errors -> no stacktrace, exit with error code.
+                is IllegalArgumentException,  -> 1
+                is SqlSyntaxCruncherException -> 11
+                is CsvCruncherException       -> 20
+                // Unknown -> Print with stacktrace.
+                else -> -1;
+            }
+            if (exitCode == -1) {
+                System.err.println("" + ex.message)
+                printBugReportingGuide(System.err, null)
+                System.exit(exitCode)
+            }
+            else {
+                //log.error("CSV Cruncher failed: " + ex.message, ex)
+                System.err.println("CSV Cruncher failed: " + ex.message + "\n" + ex)
+                System.exit(127)
+            }
         }
         catch (ex: Throwable) {
             log.error("CSV Cruncher failed: " + ex.message, ex)
@@ -62,14 +80,22 @@ object App {
         outputStream.println("  For more, read the README.md distributed with CsvCruncher, or at: https://github.com/OndraZizka/csv-cruncher#readme")
     }
 
+    internal fun printBugReportingGuide(outputStream: PrintStream, options: Options?) {
+        if (options?.logLevel == LogLevel.OFF) return;
+        outputStream.println("  If you believe this is a bug, feel free to report it at https://github.com/OndraZizka/csv-cruncher/issues")
+        outputStream.println("  but please check the open tickets first.")
+        if (options?.logLevel !in setOf(null, LogLevel.DEBUG, LogLevel.TRACE))
+            outputStream.println("  For more info about what CsvCruncher did before the error, try --logLevel=${LogLevel.DEBUG.name}")
+    }
+
     private fun setLogLevel(options: Options) {
         if (options.logLevel == null) return
 
         val configuredLevel: Level? = Level.toLevel(options.logLevel!!.name)
 
         val rootLogger: Logger = LoggerFactory.getLogger("root")
         val logBackLogger = rootLogger as ch.qos.logback.classic.Logger
-        rootLogger.debug("Changing all loggers' level to ${configuredLevel} as per option --logLevel=${options.logLevel!!.name}. Possible levels: " + LogLevel.values().joinToString(", "))
+        rootLogger.debug("Changing all loggers' level to ${configuredLevel} as per option --logLevel=${options.logLevel!!.name}. Possible levels: " + LogLevel.entries.joinToString(", "))
         logBackLogger.level = configuredLevel
 
         // For now, this needs to be synchronized with logback.xml, to override all specifically set there.

src/test/kotlin/cz/dynawest/csvcruncher/it/OptionsCombinationsTest.kt

@@ -5,9 +5,11 @@ import cz.dynawest.csvcruncher.CsvCruncherTestUtils
 import cz.dynawest.csvcruncher.CsvCruncherTestUtils.extractArgumentsFromTestCommandFormat
 import cz.dynawest.csvcruncher.CsvCruncherTestUtils.testDataDir
 import cz.dynawest.csvcruncher.CsvCruncherTestUtils.testOutputDir
+import cz.dynawest.csvcruncher.SqlSyntaxCruncherException
 import cz.dynawest.csvcruncher.app.ExportArgument.TargetType
 import cz.dynawest.csvcruncher.app.OptionsParser
 import cz.dynawest.csvcruncher.util.FilesUtils.parseColumnsFromFirstCsvLine
+import org.assertj.core.api.Assertions
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertFalse
 import org.junit.jupiter.api.Assertions.assertIterableEquals
@@ -129,6 +131,26 @@ class OptionsCombinationsTest {
         assertIterableEquals("Op,recording_group_id,status,storage_base_url,owner_id,room_id,session_id,requested_ts,created_ts,deleted_ts,updated_ts,is_deleted,acc_consumer_id".split(","), columnNames)
     }
 
+    @Test
+    fun sqlSyntaxError_noStackTrace(testInfo: TestInfo) {
+        val command =
+            " | -in  | $testDataDir/eapBuilds.csv" +
+            " | -sql | SELECT * LIMIT 1" + // SQL syntax error.
+            " | -out | $testOutputDir/sqlSyntaxError_noStackTrace.csv" +
+            " | --logLevel=ERROR"
+
+        Assertions.assertThatThrownBy {
+            CsvCruncherTestUtils.runCruncherWithArguments(command)
+        }
+            .hasNoSuppressedExceptions()
+            .hasMessageContaining("SELECT * LIMIT 1")
+            .isInstanceOf(SqlSyntaxCruncherException::class.java)
+
+        val resultCsv = Paths.get("$testOutputDir/sqlSyntaxError_noStackTrace.csv").toFile()
+        assertTrue( ! resultCsv.exists() )
+    }
+
+
     /**
      * Fails because of:
      * $table placeholder not replaced when dir input with non-canonical JSONs is used. #149