--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/kotlin/de/uapcore/lightpit/AbstractServlet.kt Fri Apr 02 11:59:14 2021 +0200
@@ -0,0 +1,182 @@
+/*
+ * Copyright 2021 Mike Becker. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package de.uapcore.lightpit
+
+import de.uapcore.lightpit.DataSourceProvider.Companion.SC_ATTR_NAME
+import de.uapcore.lightpit.dao.DataAccessObject
+import de.uapcore.lightpit.dao.createDataAccessObject
+import java.sql.SQLException
+import java.util.*
+import javax.servlet.http.HttpServlet
+import javax.servlet.http.HttpServletRequest
+import javax.servlet.http.HttpServletResponse
+
+abstract class AbstractServlet : LoggingTrait, HttpServlet() {
+
+ /**
+ * Contains the GET request mappings.
+ */
+ private val getMappings = mutableMapOf<PathPattern, MappingMethod>()
+
+ /**
+ * Contains the POST request mappings.
+ */
+ private val postMappings = mutableMapOf<PathPattern, MappingMethod>()
+
+ protected fun get(pattern: String, method: MappingMethod) {
+ getMappings[PathPattern(pattern)] = method
+ }
+
+ protected fun post(pattern: String, method: MappingMethod) {
+ postMappings[PathPattern(pattern)] = method
+ }
+
+ private fun notFound(http: HttpRequest, dao: DataAccessObject) {
+ http.response.sendError(HttpServletResponse.SC_NOT_FOUND)
+ }
+
+ private fun findMapping(
+ mappings: Map<PathPattern, MappingMethod>,
+ req: HttpServletRequest
+ ): Pair<PathPattern, MappingMethod> {
+ val requestPath = sanitizedRequestPath(req)
+ val candidates = mappings.filter { it.key.matches(requestPath) }
+ return if (candidates.isEmpty()) {
+ Pair(PathPattern(requestPath), ::notFound)
+ } else {
+ if (candidates.size > 1) {
+ logger().warn("Ambiguous mapping for request path '{}'", requestPath)
+ }
+ candidates.entries.first().toPair()
+ }
+ }
+
+ private fun invokeMapping(
+ mapping: Pair<PathPattern, MappingMethod>,
+ req: HttpServletRequest,
+ resp: HttpServletResponse,
+ dao: DataAccessObject
+ ) {
+ val params = mapping.first.obtainPathParameters(sanitizedRequestPath(req))
+ val method = mapping.second
+ logger().trace("invoke {}", method)
+ method(HttpRequest(req, resp, params), dao)
+ }
+
+ private fun sanitizedRequestPath(req: HttpServletRequest) = req.pathInfo ?: "/"
+
+ private fun doProcess(
+ req: HttpServletRequest,
+ resp: HttpServletResponse,
+ mappings: Map<PathPattern, MappingMethod>
+ ) {
+ val session = req.session
+
+ // the very first thing to do is to force UTF-8
+ req.characterEncoding = "UTF-8"
+
+ // choose the requested language as session language (if available) or fall back to english, otherwise
+ if (session.getAttribute(Constants.SESSION_ATTR_LANGUAGE) == null) {
+ val availableLanguages = availableLanguages()
+ val reqLocale = req.locale
+ val sessionLocale = if (availableLanguages.contains(reqLocale)) reqLocale else availableLanguages.first()
+ session.setAttribute(Constants.SESSION_ATTR_LANGUAGE, sessionLocale)
+ logger().debug(
+ "Setting language for new session {}: {}", session.id, sessionLocale.displayLanguage
+ )
+ } else {
+ val sessionLocale = session.getAttribute(Constants.SESSION_ATTR_LANGUAGE) as Locale
+ resp.locale = sessionLocale
+ logger().trace("Continuing session {} with language {}", session.id, sessionLocale)
+ }
+
+ // set some internal request attributes
+ val http = HttpRequest(req, resp)
+ val fullPath = req.servletPath + Optional.ofNullable(req.pathInfo).orElse("")
+ req.setAttribute(Constants.REQ_ATTR_BASE_HREF, http.baseHref)
+ req.setAttribute(Constants.REQ_ATTR_PATH, fullPath)
+ req.getHeader("Referer")?.let {
+ // TODO: add a sanity check to avoid link injection
+ req.setAttribute(Constants.REQ_ATTR_REFERER, it)
+ }
+
+ // if this is an error path, bypass the normal flow
+ if (fullPath.startsWith("/error/")) {
+ http.styleSheets = listOf("error")
+ http.render("error")
+ return
+ }
+
+ // obtain a connection and create the data access objects
+ val dsp = req.servletContext.getAttribute(SC_ATTR_NAME) as DataSourceProvider
+ val dialect = dsp.dialect
+ val ds = dsp.dataSource
+ if (ds == null) {
+ resp.sendError(
+ HttpServletResponse.SC_SERVICE_UNAVAILABLE,
+ "JNDI DataSource lookup failed. See log for details."
+ )
+ return
+ }
+ try {
+ ds.connection.use { connection ->
+ val dao = createDataAccessObject(dialect, connection)
+ try {
+ connection.autoCommit = false
+ invokeMapping(findMapping(mappings, req), req, resp, dao)
+ connection.commit()
+ } catch (ex: SQLException) {
+ logger().warn("Database transaction failed (Code {}): {}", ex.errorCode, ex.message)
+ logger().debug("Details: ", ex)
+ resp.sendError(
+ HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
+ "Unhandled Transaction Error - Code: " + ex.errorCode
+ )
+ connection.rollback()
+ }
+ }
+ } catch (ex: SQLException) {
+ logger().error("Severe Database Exception (Code {}): {}", ex.errorCode, ex.message)
+ logger().debug("Details: ", ex)
+ resp.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "Database Error - Code: " + ex.errorCode)
+ }
+ }
+
+ override fun doGet(req: HttpServletRequest, resp: HttpServletResponse) {
+ doProcess(req, resp, getMappings)
+ }
+
+ override fun doPost(req: HttpServletRequest, resp: HttpServletResponse) {
+ doProcess(req, resp, postMappings)
+ }
+
+ protected fun availableLanguages(): List<Locale> {
+ val langTags = servletContext.getInitParameter(Constants.CTX_ATTR_LANGUAGES)?.split(",")?.map(String::trim) ?: emptyList()
+ val locales = langTags.map(Locale::forLanguageTag).filter { it.language.isNotEmpty() }
+ return if (locales.isEmpty()) listOf(Locale.ENGLISH) else locales
+ }
+
+}