Java tutorial
/* ======================================================================== SchemaCrawler http://www.schemacrawler.com Copyright (c) 2000-2017, Sualeh Fatehi <sualeh@hotmail.com>. All rights reserved. ------------------------------------------------------------------------ SchemaCrawler is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. SchemaCrawler and the accompanying materials are made available under the terms of the Eclipse Public License v1.0, GNU General Public License v3 or GNU Lesser General Public License v3. You may elect to redistribute this code under any of these licenses. The Eclipse Public License is available at: http://www.eclipse.org/legal/epl-v10.html The GNU General Public License v3 and the GNU Lesser General Public License v3 are available at: http://www.gnu.org/licenses/ ======================================================================== */ package us.fatehi.schemacrawler.webapp.controller; import static java.nio.charset.StandardCharsets.UTF_8; import static us.fatehi.schemacrawler.webapp.service.storage.FileExtensionType.JSON; import static us.fatehi.schemacrawler.webapp.service.storage.FileExtensionType.PNG; import static us.fatehi.schemacrawler.webapp.service.storage.FileExtensionType.SQLITE_DB; import java.io.ByteArrayInputStream; import java.nio.file.Files; import java.nio.file.Path; import javax.validation.Valid; import org.apache.commons.lang3.exception.ExceptionUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.core.io.FileSystemResource; import org.springframework.core.io.InputStreamResource; import org.springframework.core.io.Resource; import org.springframework.http.MediaType; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.validation.BindingResult; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.servlet.mvc.support.RedirectAttributes; import us.fatehi.schemacrawler.webapp.model.SchemaCrawlerDiagramRequest; import us.fatehi.schemacrawler.webapp.service.schemacrawler.SchemaCrawlerService; import us.fatehi.schemacrawler.webapp.service.storage.StorageService; @Controller @ControllerAdvice public class SchemaCrawlerDiagramController { private static Logger logger = LoggerFactory.getLogger(SchemaCrawlerDiagramController.class); @Autowired private StorageService storageService; @Autowired private SchemaCrawlerService scService; @ExceptionHandler(Throwable.class) public String handleException(final Throwable throwable, final RedirectAttributes redirectAttributes) { // See http://www.mkyong.com/spring-boot/spring-boot-file-upload-example/ logger.error(throwable.getMessage(), throwable); final String errorMessage = ExceptionUtils.getRootCauseMessage(throwable); redirectAttributes.addFlashAttribute("errorMessage", errorMessage); return "redirect:error"; } @GetMapping(value = "/") public String index() { return "redirect:/schemacrawler"; } @ResponseBody @GetMapping(value = "/schemacrawler/images/{key}", produces = MediaType.IMAGE_PNG_VALUE) public Resource schemacrawlerDiagram(@PathVariable final String key) throws Exception { return storageService.resolve(key, PNG).map(path -> new FileSystemResource(path.toFile())) .orElseThrow(() -> new Exception("Cannot find image /schemacrawler/images/" + key)); } @GetMapping("/schemacrawler") public String schemacrawlerDiagramForm(final Model model) { model.addAttribute("diagramRequest", new SchemaCrawlerDiagramRequest()); return "SchemaCrawlerDiagramForm"; } // http://stackoverflow.com/questions/30297719/cannot-get-validation-working-with-spring-boot-and-thymeleaf @PostMapping(value = "/schemacrawler") public String schemacrawlerDiagramFormSubmit( @ModelAttribute("diagramRequest") @Valid final SchemaCrawlerDiagramRequest diagramRequest, final BindingResult bindingResult, @RequestParam("file") final MultipartFile file) throws Exception { if (bindingResult.hasErrors()) { return "SchemaCrawlerDiagramForm"; } generateSchemaCrawlerDiagram(diagramRequest, file); return "SchemaCrawlerDiagramResult"; } @GetMapping(value = "/schemacrawler/{key}") public String schemacrawlerDiagramPage(final Model model, @PathVariable final String key) throws Exception { final Path jsonFile = storageService.resolve(key, JSON) .orElseThrow(() -> new Exception("Cannot find diagram for " + key)); final SchemaCrawlerDiagramRequest diagramRequest = SchemaCrawlerDiagramRequest .fromJson(new String(Files.readAllBytes(jsonFile))); model.addAttribute("diagramRequest", diagramRequest); return "SchemaCrawlerDiagram"; } private void generateSchemaCrawlerDiagram(final SchemaCrawlerDiagramRequest diagramRequest, final MultipartFile file) throws Exception { final String key = diagramRequest.getKey(); // Store the uploaded database file storageService.store(file, key, SQLITE_DB); // Generate a database diagram, and store the generated image final Path dbFile = storageService.resolve(key, SQLITE_DB).orElseThrow( () -> new Exception(String.format("Cannot locate database file %s.%s", key, SQLITE_DB))); final Path schemaCrawlerDiagram = scService.createSchemaCrawlerDiagram(dbFile, PNG.getExtension()); storageService.store(new FileSystemResource(schemaCrawlerDiagram.toFile()), key, PNG); // Save the JSON request to disk storageService.store( new InputStreamResource(new ByteArrayInputStream(diagramRequest.toString().getBytes(UTF_8))), key, JSON); } }