refactor(rest): refactor UnitTestUpload to v2

- defined modocot URI for unittests and submissions
- directly expect a textfile, not an archive
- store config file and local repo copy in persistent place,
    instead of using Gitea

BREAKING CHANGE: file to be uploaded changed from zip to text
BREAKING CHANGE: no longer uses Gitea

src/main/java/de/hftstuttgart/rest/v1/unittest/UnitTestUpload.java

 package de.hftstuttgart.rest.v1.unittest;
 
-import de.hftstuttgart.config.ModocotProperties;
-import de.hftstuttgart.utils.BackendUtil;
-import de.hftstuttgart.utils.FileUtil;
-import de.hftstuttgart.utils.GitTeaUtil;
 import de.hftstuttgart.utils.JGitUtil;
-import de.hftstuttgart.utils.UnzipUtil;
-import io.gitea.model.Repository;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
-import org.eclipse.jgit.transport.PushResult;
+import org.springframework.core.env.Environment;
+import org.springframework.util.FileSystemUtils;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -17,13 +12,11 @@ import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
 import javax.servlet.annotation.MultipartConfig;
-import java.io.File;
-import java.io.IOException;
-import java.util.List;
-import java.util.Objects;
-import java.util.UUID;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
+import java.io.*;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /**
  * Rest controller for anything related to the TEST files.
@@ -34,93 +27,77 @@ import java.util.stream.Stream;
 public class UnitTestUpload {
 
     private static final Logger LOG = LogManager.getLogger(UnitTestUpload.class);
+    public final static String modocotTestConfigRegex = "^modocot::(.*)::(.*|none)::(.*|none)::(.*)$";
+    public final static String modocotDueConfigRegex = "^modocot::(.*)::(.*|none)::(.*|none)$";
 
-    private final ModocotProperties modocotProperties;
-    private final GitTeaUtil gitTeaUtil;
     private final JGitUtil jGitUtil;
     private final String assignmentBasePath;
 
-    public UnitTestUpload(ModocotProperties modocotProperties,
-                          GitTeaUtil gitTeaUtil,
-                          JGitUtil jGitUtil) {
-        this.modocotProperties = modocotProperties;
-        this.gitTeaUtil = gitTeaUtil;
+    public UnitTestUpload(Environment env, JGitUtil jGitUtil) {
         this.jGitUtil = jGitUtil;
-        this.assignmentBasePath =
-                modocotProperties.getModocotParentDirectory()
-                + File.separator
-                + modocotProperties.getModocotAssignmentFolderPrefix();
+
+        Path p = Paths.get(env.getProperty("modocot.dir"), env.getProperty("modocot.dir.test.folder.name"));
+        this.assignmentBasePath = p.toAbsolutePath().toString();
     }
 
     /**
      * Create a subfolder for the specific assignment.
      * This is called when the teacher creates an assignment and uploads the JUnit test files
      *
-     * @param unitTestFileRef The zip file which contains the JUnit tests
+     * @param unitTestFileRef The text file which contains the JUnit tests meta data
      * @param assignmentId    ID of the created assignment. Generated by Moodle
      */
     @RequestMapping(method = RequestMethod.POST)
-    public void uploadUnitTestFile(@RequestParam("unitTestFile") MultipartFile unitTestFileRef, @RequestParam("assignmentId") String assignmentId) throws IOException {
-
-        // path to the directory in which we will be working
-        String subFolderPath = this.assignmentBasePath + assignmentId;
-
-        LOG.info("work-directory: " + subFolderPath);
-        // creating the work-directory
-        File workDirectory = new File(subFolderPath);
-        workDirectory.mkdirs();
-
-        // creating the file which the unitTestFileRef will be transferred into
-        File file = new File(subFolderPath, String.valueOf(UUID.randomUUID()));
-
-        // transferring MultipartFile into temporary file
+    public void uploadUnitTestFile(
+        @RequestParam("unitTestFile") MultipartFile unitTestFileRef,
+        @RequestParam("assignmentId") String assignmentId
+    ) throws IOException {
+        LOG.info("received new assignment");
+
+        File file = Paths.get(
+                this.assignmentBasePath,
+                assignmentId + ".txt")
+            .toFile();
+        file.mkdirs();
+
+        // save assignment config
         unitTestFileRef.transferTo(file);
-
-        // unzipping temporary file to work-directory
-        List<File> zipFiles = UnzipUtil.unzip(file);
-
-        // unzipping temporary file (not needed anymore)
-        if (file.exists()) file.delete();
-
-        // check if any extracted files are named repo.txt
-        if (zipFiles.stream().anyMatch(zipFile -> zipFile.getName().equalsIgnoreCase("repo.txt"))) {
-            // reading all from the  repo.txt
-            List<String> lines = BackendUtil.extractLinesFromRepoFile(zipFiles, "repo.txt");
-            // either set the first line of repo.txt or ""
-            String repoUrl = (lines.size() > 0 && !lines.get(0).equals("")) ?
-                    lines.get(0) : "";
-            LOG.info("repoUrl: " + repoUrl);
-            // either set the second line of repo.txt or null
-            String credentials = ((lines.size() > 1) && !lines.get(1).equals("")) ?
-                    lines.get(1) : null;
-            LOG.info("credentials: " + credentials);
-            // cloning repository repoUrl into work-directory, using credentials from second line in repo.txt
-            this.jGitUtil.cloneRepository(repoUrl, workDirectory, credentials, credentials != null,true);
-        }
-
-        Stream.of(Objects.requireNonNull(workDirectory.listFiles()))
-                .forEach(fi -> System.out.println(fi.getAbsolutePath()));
-
-        if(this.gitTeaUtil.repositoryExists(assignmentId)) {
-            this.gitTeaUtil.deleteRepository(assignmentId);
+        LOG.debug(String.format("saved config file to: %s", file.getAbsolutePath()));
+
+        Pattern pattern = Pattern.compile(this.modocotTestConfigRegex);
+        Matcher config = null;
+
+        LOG.debug("reading test configuration file");
+        // open saved config in a try-with
+        try (BufferedReader br = new BufferedReader(
+            new InputStreamReader(
+                new FileInputStream(file)))) {
+            String line;
+
+            // search for a modocot URI while none is found and there are lines left
+            while (config == null && (line = br.readLine()) != null) {
+                Matcher matcher = pattern.matcher(line);
+                if (matcher.matches()) {
+                    LOG.debug(String.format("found modocot test line: %s", line));
+                    config = matcher;
+                }
+            }
+        } catch (IOException e) {
+            LOG.error("Error while reading repo config", e);
         }
-        // creating repository on internal giTea, name = assignmentId
-        Repository repo = this.gitTeaUtil.createRepository(assignmentId);
-        System.out.println(repo);
-        // giTea runs in docker and returns CloneUrl as localhost, replacing localhost with docker-host ip
-        repo.setCloneUrl(repo.getCloneUrl().replace("localhost", modocotProperties.getDockerHostIp()));
-
-        // committing everything in work-directory and push to created repository
-        Iterable<PushResult> pushResults = this.jGitUtil.commitAllAndPush(workDirectory, repo, false);
-        if (pushResults != null) {
-            for (PushResult pushResult : pushResults) {
-                LOG.info("Push-Result: " + pushResult.getMessages());
+        finally {
+            if (config == null) {
+                throw new RuntimeException("couldn't find repo config for unittest clone");
             }
         }
-        // deleting created work-directory
-        FileUtil.deleteFolderRecursively(workDirectory);
 
-        LOG.info("Uploaded unit test file: " + workDirectory);
+        LOG.debug("calling test repo clone");
+        // cloning assignment repo to persistent space
+        jGitUtil.cloneRepository(
+            config,
+            Paths.get(this.assignmentBasePath, assignmentId).toAbsolutePath().toString());
+
+        LOG.info(String.format("stored new assignment: %s", file.getAbsolutePath()));
     }
 
     /**
@@ -133,10 +110,21 @@ public class UnitTestUpload {
      */
     @RequestMapping(method = RequestMethod.DELETE)
     public void deleteUnitTestFiles(@RequestParam("assignmentId") String assignmentId) {
-        String path = this.assignmentBasePath + assignmentId;
-        File dir = new File(path);
-        if (dir.exists()) {
-            FileUtil.deleteFolderRecursively(dir);
-        }
+        LOG.info(String.format("received deletion order for assignment %s", assignmentId));
+
+        // deleting config file
+        File file = Paths.get(
+            this.assignmentBasePath,
+            assignmentId + ".txt")
+            .toFile();
+        file.delete();
+
+        // deleting local copy of repository
+        file = Paths.get(
+            this.assignmentBasePath,
+            assignmentId).toFile();
+        FileSystemUtils.deleteRecursively(file);
+
+        LOG.info(String.format("assignment %s deletion complete", assignmentId));
     }
 }