com.hhandoko.cassandra.migration.internal.dbsupport.CqlScript.kt Maven / Gradle / Ivy
/**
* File : CqlScript.kt
* License :
* Original - Copyright (c) 2010 - 2016 Boxfuse GmbH
* Derivative - Copyright (c) 2016 - 2018 cassandra-migration Contributors
*
* 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
*
* http://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.
*/
package com.hhandoko.cassandra.migration.internal.dbsupport
import com.datastax.driver.core.Session
import com.datastax.driver.core.SimpleStatement
import com.hhandoko.cassandra.migration.api.CassandraMigrationException
import com.hhandoko.cassandra.migration.internal.util.StringUtils
import com.hhandoko.cassandra.migration.internal.util.logging.LogFactory
import com.hhandoko.cassandra.migration.internal.util.scanner.Resource
import java.io.BufferedReader
import java.io.IOException
import java.io.Reader
import java.io.StringReader
import java.util.*
/**
* CQL script containing a series of statements terminated by a delimiter (eg: ;).
* Single-line (--) and multi-line (/ ** * /) comments are stripped and ignored.
*/
class CqlScript {
/**
* The CQL statements contained in this script.
*/
val cqlStatements: List
/**
* The resource containing the statements.
*/
val resource: Resource?
/**
* The CQL script read timeout in milliseconds.
*/
val timeout: Int
/**
* Creates a new CQL script from this source.
*
* @param cqlScriptSource The cql script as a text block with all placeholders already replaced.
*/
constructor(cqlScriptSource: String) {
this.cqlStatements = parse(cqlScriptSource)
this.resource = null
this.timeout = 0
}
/**
* Creates a new CQL script from this resource.
*
* @param cqlScriptResource The resource containing the statements.
* @param encoding The encoding to use.
* @param timeout The script read timeout in seconds.
*/
constructor(cqlScriptResource: Resource, encoding: String, timeout: Int) {
val cqlScriptSource = cqlScriptResource.loadAsString(encoding)
this.cqlStatements = parse(cqlScriptSource)
this.resource = cqlScriptResource
this.timeout = timeout * 1000 // Convert from seconds to milliseconds
}
/**
* Executes this script against the database.
*
* @param session The Cassandra session connection to use to execute the migration.
*/
fun execute(session: Session) {
cqlStatements.forEach {
LOG.debug("Executing CQL: $it")
when {
timeout > 0 -> session.execute(SimpleStatement(it).setReadTimeoutMillis(timeout))
else -> session.execute(it)
}
}
}
/**
* Parses this script's source into statements.
*
* @param cqlScriptSource The script source to parse.
* @return The parsed statements.
*/
private fun parse(cqlScriptSource: String): List {
return linesToStatements(readLines(StringReader(cqlScriptSource)))
}
/**
* Turns these lines in a series of statements.
*
* @param lines The lines to analyse.
* @return The statements contained in these lines (in order).
*/
private fun linesToStatements(lines: List): List {
val statements = ArrayList()
var nonStandardDelimiter: Delimiter? = null
var cqlStatementBuilder = CqlStatementBuilder()
for (lineNumber in 1..lines.size) {
val line = lines[lineNumber - 1]
if (cqlStatementBuilder.isEmpty) {
if (!StringUtils.hasText(line)) {
// Skip empty line between statements.
continue
}
val newDelimiter = cqlStatementBuilder.extractNewDelimiterFromLine(line)
if (newDelimiter != null) {
nonStandardDelimiter = newDelimiter
// Skip this line as it was an explicit delimiter change directive outside of any statements.
continue
}
cqlStatementBuilder.setLineNumber(lineNumber)
// Start a new statement, marking it with this line number.
if (nonStandardDelimiter != null) {
cqlStatementBuilder.setDelimiter(nonStandardDelimiter)
}
}
cqlStatementBuilder.addLine(line)
if (cqlStatementBuilder.canDiscard()) {
cqlStatementBuilder = CqlStatementBuilder()
} else if (cqlStatementBuilder.isTerminated) {
val cqlStatement = cqlStatementBuilder.cqlStatement
statements.add(cqlStatement)
LOG.debug("Found statement: $cqlStatement")
cqlStatementBuilder = CqlStatementBuilder()
}
}
// Catch any statements not followed by delimiter.
if (!cqlStatementBuilder.isEmpty) {
statements.add(cqlStatementBuilder.cqlStatement)
}
return statements
}
/**
* Parses the textual data provided by this reader into a list of lines.
*
* @param reader The reader for the textual data.
* @return The list of lines (in order).
* @throws IllegalStateException when the textual data parsing failed.
* @throws CassandraMigrationException when textual data parsing failed.
*/
private fun readLines(reader: Reader): List {
try {
return BufferedReader(reader).lineSequence().toList()
} catch (e: IOException) {
val message = if (resource != null) { "${resource.location} (${resource.locationOnDisk})" } else "lines"
throw CassandraMigrationException("Unable to parse $message", e)
}
}
/**
* CqlScript companion object.
*/
companion object {
private val LOG = LogFactory.getLog(CqlScript::class.java)
}
}