SEBSP-210 screenshot data session cache PoC impl

Author: anhefti

src/main/java/ch/ethz/seb/sps/server/datalayer/dao/impl/ScreenshotDataDAOBatis.java

@@ -255,14 +255,19 @@ public Result<Map<String, ScreenshotDataRecord>> allOfMappedToSession(final List
             if (pks == null || pks.isEmpty()) {
                 return Collections.emptyMap();
             }
+            
+            // TODO only for testing remove this
+            if (log.isDebugEnabled()) {
+                log.debug("Get Screenshotdata for gallery view: {}", pks);
+            }
 
             return screenshotDataRecordMapper
                     .selectByExample()
                     .where(id, isIn(pks))
                     .build()
                     .execute()
                     .stream()
-                    .collect(Collectors.toMap(r -> r.getSessionUuid(), Function.identity()));
+                    .collect(Collectors.toMap(ScreenshotDataRecord::getSessionUuid, Function.identity()));
         });
     }
 

src/main/java/ch/ethz/seb/sps/server/datalayer/dao/impl/ScreenshotDataLiveCacheDAOBatis.java

@@ -37,7 +37,7 @@ public ScreenshotDataLiveCacheDAOBatis(ScreenshotDataLiveCacheRecordMapper scree
     @Transactional
     public Result<ScreenshotDataLiveCacheRecord> createCacheEntry(String sessionUUID) {
         return Result
-            .tryCatch(() ->  screenshotDataLiveCacheRecordMapper.selectByPrimaryKey(createSlot(sessionUUID, -1L)))
+            .tryCatch(() ->  screenshotDataLiveCacheRecordMapper.selectByPrimaryKey(createSlot(sessionUUID, null)))
             .onError(TransactionHandler::rollback);
     }
 
@@ -87,14 +87,20 @@ public Result<List<String>> deleteAll(List<String> sessionUUIDs) {
     @Override
     @Transactional(readOnly = true)
     public Result<Collection<ScreenshotDataLiveCacheRecord>> getAll() {
-        return Result.tryCatch(() -> screenshotDataLiveCacheRecordMapper.selectByExample().build().execute());
+        return Result.tryCatch(() -> {
+            final List<ScreenshotDataLiveCacheRecord> execute = screenshotDataLiveCacheRecordMapper
+                    .selectByExample()
+                    .build()
+                    .execute();
+            return execute;
+        });
     }
 
     private synchronized Long createSlot(String sessionUUID, Long value) {
         final ScreenshotDataLiveCacheRecord rec = new ScreenshotDataLiveCacheRecord(
                 null,
                 sessionUUID,
-                value );
+                value != null && value >= 0 ? value : null );
 
         screenshotDataLiveCacheRecordMapper.insert(rec);
         return rec.getId();

src/main/java/ch/ethz/seb/sps/server/servicelayer/impl/LiveProctoringCacheServiceImpl.java

@@ -107,7 +107,6 @@ public void init() {
                     this::updateFromStoreCache,
                     DateTime.now(DateTimeZone.UTC).toDate().toInstant(),
                     Duration.ofMillis(this.batchInterval));
-
 
         } catch (Exception e) {
             ServiceInit.INIT_LOGGER.error("----> Live Proctoring Cache Service : failed to initialized", e);
@@ -142,16 +141,10 @@ public Long getLatestSSDataId(final String sessionUUID, final boolean createSlot
     public void updateCacheStore(final Collection<ScreenshotQueueData> batch) {
         try {
 
-//            // TODO check if this is really necessary 
-//            // fist ensure that all slots are existing
-//            batch.forEach(data -> {
-//                if (!cache.containsKey(data.record.getSessionUuid())) {
-//                    log.warn("Missing cache slot, try to create one...");
-//                    screenshotDataLiveCacheDAO.createCacheEntry(data.record.getSessionUuid())
-//                            .onError(error -> log.error("Failed to create cache entry: {}", error.getMessage()));
-//                }
-//            });
-//            
+            if (log.isDebugEnabled()) {
+                log.debug("Update store cache with batch of: {}", batch.size());
+            }
+            
             // then batch update
             this.transactionTemplate.executeWithoutResult(status -> {
                 batch.forEach(data -> {
@@ -236,7 +229,7 @@ private void updateFromStoreCache() {
                     .stream()
                     .collect(Collectors.toMap(
                             ScreenshotDataLiveCacheRecord::getSessionUuid,
-                            ScreenshotDataLiveCacheRecord::getIdLatestSsd
+                            rec -> rec.getIdLatestSsd() == null ? -1L : rec.getIdLatestSsd()
                     ));
 
             cache.putAll(newValues);

src/main/java/ch/ethz/seb/sps/server/weblayer/AdminProctorController.java

@@ -15,6 +15,7 @@
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Collectors;
 
+import ch.ethz.seb.sps.domain.api.TooManyRequests;
 import ch.ethz.seb.sps.domain.model.EntityType;
 import ch.ethz.seb.sps.domain.model.service.DistinctMetadataWindowForExam;
 import ch.ethz.seb.sps.domain.model.service.UserListForApplicationSearch;
@@ -76,7 +77,7 @@ public class AdminProctorController {
     private final GroupingService groupingService;
     private final UserService userService;
 
-    private AtomicInteger criticalRequestBucket = new AtomicInteger(10);
+    private AtomicInteger criticalRequestBucket = new AtomicInteger(2);
 
     public AdminProctorController(
             final GroupDAO groupDAO,
@@ -232,7 +233,8 @@ public ScreenshotsInGroupData getSessionsByGroup(
                 log.warn("criticalRequestBucket empty! This will deny request in the future");
             }
         }
-        criticalRequestBucket.decrementAndGet();
+        int token = criticalRequestBucket.decrementAndGet();
+        System.out.println("******************* token" + token);
 
         this.proctoringService.checkMonitoringAccess(groupUUID);
 
@@ -297,9 +299,15 @@ public ScreenshotViewData getScreenshotViewData(
         if (criticalRequestBucket.get() <= 0) {
             if (log.isDebugEnabled()) {
                 log.warn("criticalRequestBucket empty! This will deny request in the future");
+                throw new TooManyRequests();
             }
         }
-        criticalRequestBucket.decrementAndGet();
+        int token = criticalRequestBucket.decrementAndGet();
+        System.out.println("******************* token " + token);
+        
+        try {
+            Thread.sleep(10000);
+        } catch (Exception e) {}
 
         Long ts = null;
         if (StringUtils.isNotBlank(timestamp)) {