Abstracting out Cassandra.

17 files changed, 519 insertions, 164 deletions

diff --git a/src/com/p4square/grow/backend/CassandraGrowData.java b/src/com/p4square/grow/backend/CassandraGrowData.java
new file mode 100644
index 0000000..22a7716
--- /dev/null
+++ b/src/com/p4square/grow/backend/CassandraGrowData.java
@@ -0,0 +1,172 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.backend;
+
+import java.io.IOException;
+
+import com.p4square.grow.config.Config;
+
+import com.p4square.grow.backend.db.CassandraDatabase;
+import com.p4square.grow.backend.db.CassandraKey;
+import com.p4square.grow.backend.db.CassandraProviderImpl;
+import com.p4square.grow.backend.db.CassandraCollectionProvider;
+import com.p4square.grow.backend.db.CassandraTrainingRecordProvider;
+
+import com.p4square.grow.model.Message;
+import com.p4square.grow.model.MessageThread;
+import com.p4square.grow.model.Playlist;
+import com.p4square.grow.model.Question;
+import com.p4square.grow.model.TrainingRecord;
+import com.p4square.grow.model.UserRecord;
+
+import com.p4square.grow.provider.CollectionProvider;
+import com.p4square.grow.provider.DelegateCollectionProvider;
+import com.p4square.grow.provider.DelegateProvider;
+import com.p4square.grow.provider.Provider;
+
+/**
+ *
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+class CassandraGrowData implements GrowData {
+    private static final String DEFAULT_COLUMN = "value";
+
+    private final Config mConfig;
+    private final CassandraDatabase mDatabase;
+
+    private final Provider<String, UserRecord> mUserRecordProvider;
+
+    private final Provider<String, Question> mQuestionProvider;
+    private final CassandraTrainingRecordProvider mTrainingRecordProvider;
+    private final CollectionProvider<String, String, String> mVideoProvider;
+
+    private final CollectionProvider<String, String, MessageThread> mFeedThreadProvider;
+    private final CollectionProvider<String, String, Message> mFeedMessageProvider;
+
+    private final Provider<String, String> mStringProvider;
+
+    private final CollectionProvider<String, String, String> mAnswerProvider;
+
+    public CassandraGrowData(final Config config) {
+        mConfig = config;
+        mDatabase = new CassandraDatabase();
+
+        mUserRecordProvider = new DelegateProvider<String, CassandraKey, UserRecord>(
+                new CassandraProviderImpl<UserRecord>(mDatabase, UserRecord.class)) {
+            @Override
+            public CassandraKey makeKey(String userid) {
+                return new CassandraKey("accounts", userid, DEFAULT_COLUMN);
+            }
+        };
+
+        mQuestionProvider = new DelegateProvider<String, CassandraKey, Question>(
+                new CassandraProviderImpl<Question>(mDatabase, Question.class)) {
+            @Override
+            public CassandraKey makeKey(String questionId) {
+                return new CassandraKey("strings", "/questions/" + questionId, DEFAULT_COLUMN);
+            }
+        };
+
+        mFeedThreadProvider = new CassandraCollectionProvider<MessageThread>(mDatabase,
+                "feedthreads", MessageThread.class);
+        mFeedMessageProvider = new CassandraCollectionProvider<Message>(mDatabase,
+                "feedmessages", Message.class);
+
+        mTrainingRecordProvider = new CassandraTrainingRecordProvider(mDatabase);
+
+        mVideoProvider = new DelegateCollectionProvider<String, String, String, String, String>(
+                new CassandraCollectionProvider<String>(mDatabase, "strings", String.class)) {
+            @Override
+            public String makeCollectionKey(String key) {
+                return "/training/" + key;
+            }
+
+            @Override
+            public String makeKey(String key) {
+                return key;
+            }
+
+            @Override
+            public String unmakeKey(String key) {
+                return key;
+            }
+        };
+
+        mStringProvider = new DelegateProvider<String, CassandraKey, String>(
+                new CassandraProviderImpl<String>(mDatabase, String.class)) {
+            @Override
+            public CassandraKey makeKey(String id) {
+                return new CassandraKey("strings", id, DEFAULT_COLUMN);
+            }
+        };
+
+        mAnswerProvider = new CassandraCollectionProvider<String>(
+                mDatabase, "assessments", String.class);
+    }
+
+    @Override
+    public void start() throws Exception {
+        mDatabase.setClusterName(mConfig.getString("clusterName", "Dev Cluster"));
+        mDatabase.setKeyspaceName(mConfig.getString("keyspace", "GROW"));
+        mDatabase.init();
+    }
+
+    @Override
+    public void stop() throws Exception {
+        mDatabase.close();
+    }
+
+    /**
+     * @return the current database.
+     */
+    public CassandraDatabase getDatabase() {
+        return mDatabase;
+    }
+
+    @Override
+    public Provider<String, UserRecord> getUserRecordProvider() {
+        return mUserRecordProvider;
+    }
+
+    @Override
+    public Provider<String, Question> getQuestionProvider() {
+        return mQuestionProvider;
+    }
+
+    @Override
+    public Provider<String, TrainingRecord> getTrainingRecordProvider() {
+        return mTrainingRecordProvider;
+    }
+
+    @Override
+    public CollectionProvider<String, String, String> getVideoProvider() {
+        return mVideoProvider;
+    }
+
+    @Override
+    public Playlist getDefaultPlaylist() throws IOException {
+        return mTrainingRecordProvider.getDefaultPlaylist();
+    }
+
+    @Override
+    public CollectionProvider<String, String, MessageThread> getThreadProvider() {
+        return mFeedThreadProvider;
+    }
+
+    @Override
+    public CollectionProvider<String, String, Message> getMessageProvider() {
+        return mFeedMessageProvider;
+    }
+
+    @Override
+    public Provider<String, String> getStringProvider() {
+        return mStringProvider;
+    }
+
+    @Override
+    public CollectionProvider<String, String, String> getAnswerProvider() {
+        return mAnswerProvider;
+    }
+}
diff --git a/src/com/p4square/grow/backend/GrowBackend.java b/src/com/p4square/grow/backend/GrowBackend.java
index e747a1b..49d064c 100644
--- a/src/com/p4square/grow/backend/GrowBackend.java
+++ b/src/com/p4square/grow/backend/GrowBackend.java
@@ -18,12 +18,6 @@ import org.restlet.routing.Router;
 
 import com.p4square.grow.config.Config;
 
-import com.p4square.grow.backend.db.CassandraDatabase;
-import com.p4square.grow.backend.db.CassandraKey;
-import com.p4square.grow.backend.db.CassandraProviderImpl;
-import com.p4square.grow.backend.db.CassandraCollectionProvider;
-import com.p4square.grow.backend.db.CassandraTrainingRecordProvider;
-
 import com.p4square.grow.model.Message;
 import com.p4square.grow.model.MessageThread;
 import com.p4square.grow.model.Playlist;
@@ -32,7 +26,6 @@ import com.p4square.grow.model.TrainingRecord;
 import com.p4square.grow.model.UserRecord;
 
 import com.p4square.grow.provider.CollectionProvider;
-import com.p4square.grow.provider.DelegateProvider;
 import com.p4square.grow.provider.Provider;
 import com.p4square.grow.provider.ProvidesQuestions;
 import com.p4square.grow.provider.ProvidesTrainingRecords;
@@ -54,23 +47,12 @@ import com.p4square.grow.backend.feed.TopicResource;
  *
  * @author Jesse Morgan <jesse@jesterpm.net>
  */
-public class GrowBackend extends Application
-        implements ProvidesQuestions, ProvidesTrainingRecords, FeedDataProvider,
-          ProvidesUserRecords {
-    private static final String DEFAULT_COLUMN = "value";
+public class GrowBackend extends Application implements GrowData {
 
     private final static Logger LOG = Logger.getLogger(GrowBackend.class);
 
     private final Config mConfig;
-    private final CassandraDatabase mDatabase;
-
-    private final Provider<String, UserRecord> mUserRecordProvider;
-
-    private final Provider<String, Question> mQuestionProvider;
-    private final CassandraTrainingRecordProvider mTrainingRecordProvider;
-
-    private final CollectionProvider<String, String, MessageThread> mFeedThreadProvider;
-    private final CollectionProvider<String, String, Message> mFeedMessageProvider;
+    private final GrowData mGrowData;
 
     public GrowBackend() {
         this(new Config());
@@ -78,30 +60,8 @@ public class GrowBackend extends Application
 
     public GrowBackend(Config config) {
         mConfig = config;
-        mDatabase = new CassandraDatabase();
-
-        mUserRecordProvider = new DelegateProvider<String, CassandraKey, UserRecord>(
-                new CassandraProviderImpl<UserRecord>(mDatabase, UserRecord.class)) {
-            @Override
-            public CassandraKey makeKey(String userid) {
-                return new CassandraKey("accounts", userid, DEFAULT_COLUMN);
-            }
-        };
 
-        mQuestionProvider = new DelegateProvider<String, CassandraKey, Question>(
-                new CassandraProviderImpl<Question>(mDatabase, Question.class)) {
-            @Override
-            public CassandraKey makeKey(String questionId) {
-                return new CassandraKey("strings", "/questions/" + questionId, DEFAULT_COLUMN);
-            }
-        };
-
-        mFeedThreadProvider = new CassandraCollectionProvider<MessageThread>(mDatabase,
-                "feedthreads", MessageThread.class);
-        mFeedMessageProvider = new CassandraCollectionProvider<Message>(mDatabase,
-                "feedmessages", Message.class);
-
-        mTrainingRecordProvider = new CassandraTrainingRecordProvider(mDatabase);
+        mGrowData = new CassandraGrowData(config);
     }
 
     @Override
@@ -146,10 +106,7 @@ public class GrowBackend extends Application
     public void start() throws Exception {
         super.start();
 
-        // Setup database
-        mDatabase.setClusterName(mConfig.getString("clusterName", "Dev Cluster"));
-        mDatabase.setKeyspaceName(mConfig.getString("keyspace", "GROW"));
-        mDatabase.init();
+        mGrowData.start();
     }
 
     /**
@@ -158,48 +115,56 @@ public class GrowBackend extends Application
     @Override
     public void stop() throws Exception {
         LOG.info("Shutting down...");
-        mDatabase.close();
+        mGrowData.stop();
 
         super.stop();
     }
 
-    /**
-     * @return the current database.
-     */
-    public CassandraDatabase getDatabase() {
-        return mDatabase;
-    }
-
     @Override
     public Provider<String, UserRecord> getUserRecordProvider() {
-        return mUserRecordProvider;
+        return mGrowData.getUserRecordProvider();
     }
 
     @Override
     public Provider<String, Question> getQuestionProvider() {
-        return mQuestionProvider;
+        return mGrowData.getQuestionProvider();
+    }
+
+    @Override
+    public CollectionProvider<String, String, String> getVideoProvider() {
+        return mGrowData.getVideoProvider();
     }
 
     @Override
     public Provider<String, TrainingRecord> getTrainingRecordProvider() {
-        return mTrainingRecordProvider;
+        return mGrowData.getTrainingRecordProvider();
     }
 
     /**
      * @return the Default Playlist.
      */
     public Playlist getDefaultPlaylist() throws IOException {
-        return mTrainingRecordProvider.getDefaultPlaylist();
+        return mGrowData.getDefaultPlaylist();
     }
 
     @Override
     public CollectionProvider<String, String, MessageThread> getThreadProvider() {
-        return mFeedThreadProvider;
+        return mGrowData.getThreadProvider();
     }
 
     @Override
     public CollectionProvider<String, String, Message> getMessageProvider() {
-        return mFeedMessageProvider;
+        return mGrowData.getMessageProvider();
+    }
+
+    @Override
+    public Provider<String, String> getStringProvider() {
+        return mGrowData.getStringProvider();
+    }
+
+    @Override
+    public CollectionProvider<String, String, String> getAnswerProvider() {
+        return mGrowData.getAnswerProvider();
     }
 
     /**
diff --git a/src/com/p4square/grow/backend/GrowData.java b/src/com/p4square/grow/backend/GrowData.java
new file mode 100644
index 0000000..293bb88
--- /dev/null
+++ b/src/com/p4square/grow/backend/GrowData.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.backend;
+
+import com.p4square.grow.backend.feed.FeedDataProvider;
+import com.p4square.grow.model.Playlist;
+import com.p4square.grow.provider.ProvidesAssessments;
+import com.p4square.grow.provider.ProvidesQuestions;
+import com.p4square.grow.provider.ProvidesStrings;
+import com.p4square.grow.provider.ProvidesTrainingRecords;
+import com.p4square.grow.provider.ProvidesUserRecords;
+import com.p4square.grow.provider.ProvidesVideos;
+
+/**
+ * Aggregate of the data provider interfaces.
+ *
+ * Used by GrowBackend to swap out implementations of the providers.
+ *
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+interface GrowData extends ProvidesQuestions, ProvidesTrainingRecords, ProvidesVideos,
+                                   FeedDataProvider, ProvidesUserRecords, ProvidesStrings,
+                                   ProvidesAssessments {
+
+    /**
+     * Start the data provider.
+     */
+    void start() throws Exception;
+
+    /**
+     * Stop the data provider.
+     */
+    void stop() throws Exception;
+}
diff --git a/src/com/p4square/grow/backend/db/CassandraCollectionProvider.java b/src/com/p4square/grow/backend/db/CassandraCollectionProvider.java
index 5e83247..bfcb48d 100644
--- a/src/com/p4square/grow/backend/db/CassandraCollectionProvider.java
+++ b/src/com/p4square/grow/backend/db/CassandraCollectionProvider.java
@@ -80,7 +80,11 @@ public class CassandraCollectionProvider<V> implements CollectionProvider<String
      * @throws IOException if the object cannot be encoded.
      */
     protected String encode(V obj) throws IOException {
-        return JsonEncodedProvider.MAPPER.writeValueAsString(obj);
+        if (mClazz == String.class) {
+            return (String) obj;
+        } else {
+            return JsonEncodedProvider.MAPPER.writeValueAsString(obj);
+        }
     }
 
     /**
@@ -95,6 +99,10 @@ public class CassandraCollectionProvider<V> implements CollectionProvider<String
             return null;
         }
 
+        if (mClazz == String.class) {
+            return (V) blob;
+        }
+
         V obj = JsonEncodedProvider.MAPPER.readValue(blob, mClazz);
         return obj;
     }
diff --git a/src/com/p4square/grow/backend/db/CassandraProviderImpl.java b/src/com/p4square/grow/backend/db/CassandraProviderImpl.java
index da5a9f2..9d896e7 100644
--- a/src/com/p4square/grow/backend/db/CassandraProviderImpl.java
+++ b/src/com/p4square/grow/backend/db/CassandraProviderImpl.java
@@ -26,12 +26,20 @@ public class CassandraProviderImpl<V> extends JsonEncodedProvider<V> implements
     @Override
     public V get(CassandraKey key) throws IOException {
         String blob = mDb.getKey(key.getColumnFamily(), key.getId(), key.getColumn());
+        if (mClazz == String.class) {
+            return (V) blob;
+        }
         return decode(blob);
     }
 
     @Override
     public void put(CassandraKey key, V obj) throws IOException {
-        String blob = encode(obj);
+        String blob;
+        if (mClazz == String.class) {
+            blob = (String) obj;
+        } else {
+            blob = encode(obj);
+        }
         mDb.putKey(key.getColumnFamily(), key.getId(), key.getColumn(), blob);
     }
 }
diff --git a/src/com/p4square/grow/backend/resources/BannerResource.java b/src/com/p4square/grow/backend/resources/BannerResource.java
index 8519f64..2b9c8e6 100644
--- a/src/com/p4square/grow/backend/resources/BannerResource.java
+++ b/src/com/p4square/grow/backend/resources/BannerResource.java
@@ -17,9 +17,9 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import org.apache.log4j.Logger;
 
 import com.p4square.grow.backend.GrowBackend;
-import com.p4square.grow.backend.db.CassandraDatabase;
 import com.p4square.grow.model.Banner;
 import com.p4square.grow.provider.JsonEncodedProvider;
+import com.p4square.grow.provider.Provider;
 
 /**
  * Fetches or sets the banner string.
@@ -31,14 +31,14 @@ public class BannerResource extends ServerResource {
 
     public static final ObjectMapper MAPPER = JsonEncodedProvider.MAPPER;
 
-    private CassandraDatabase mDb;
+    private Provider<String, String> mStringProvider;
 
     @Override
     public void doInit() {
         super.doInit();
 
         final GrowBackend backend = (GrowBackend) getApplication();
-        mDb = backend.getDatabase();
+        mStringProvider = backend.getStringProvider();
     }
 
     /**
@@ -46,7 +46,13 @@ public class BannerResource extends ServerResource {
      */
     @Override
     protected Representation get() {
-        String result = mDb.getKey("strings", "banner");
+        String result = null;
+        try {
+            result = mStringProvider.get("banner");
+
+        } catch (IOException e) {
+            LOG.warn("Exception loading banner: " + e);
+        }
 
         if (result == null || result.length() == 0) {
             result = "{\"html\":null}";
@@ -67,7 +73,7 @@ public class BannerResource extends ServerResource {
 
             Banner banner = representation.getObject();
 
-            mDb.putKey("strings", "banner", MAPPER.writeValueAsString(banner));
+            mStringProvider.put("banner", MAPPER.writeValueAsString(banner));
             setStatus(Status.SUCCESS_NO_CONTENT);
 
         } catch (IOException e) {
diff --git a/src/com/p4square/grow/backend/resources/SurveyResource.java b/src/com/p4square/grow/backend/resources/SurveyResource.java
index 497978f..8723ee2 100644
--- a/src/com/p4square/grow/backend/resources/SurveyResource.java
+++ b/src/com/p4square/grow/backend/resources/SurveyResource.java
@@ -13,14 +13,17 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 
 import org.restlet.data.MediaType;
 import org.restlet.data.Status;
-import org.restlet.resource.ServerResource;
+import org.restlet.ext.jackson.JacksonRepresentation;
 import org.restlet.representation.Representation;
 import org.restlet.representation.StringRepresentation;
+import org.restlet.resource.ServerResource;
 
 import org.apache.log4j.Logger;
 
 import com.p4square.grow.backend.GrowBackend;
-import com.p4square.grow.backend.db.CassandraDatabase;
+import com.p4square.grow.model.Question;
+import com.p4square.grow.provider.JsonEncodedProvider;
+import com.p4square.grow.provider.Provider;
 
 /**
  * This resource manages assessment questions.
@@ -30,9 +33,10 @@ import com.p4square.grow.backend.db.CassandraDatabase;
 public class SurveyResource extends ServerResource {
     private static final Logger LOG = Logger.getLogger(SurveyResource.class);
 
-    private static final ObjectMapper MAPPER = new ObjectMapper();
+    private static final ObjectMapper MAPPER = JsonEncodedProvider.MAPPER;
 
-    private CassandraDatabase mDb;
+    private Provider<String, Question> mQuestionProvider;
+    private Provider<String, String> mStringProvider;
 
     private String mQuestionId;
 
@@ -41,7 +45,8 @@ public class SurveyResource extends ServerResource {
         super.doInit();
 
         final GrowBackend backend = (GrowBackend) getApplication();
-        mDb = backend.getDatabase();
+        mQuestionProvider = backend.getQuestionProvider();
+        mStringProvider = backend.getStringProvider();
 
         mQuestionId = getAttribute("questionId");
     }
@@ -71,13 +76,22 @@ public class SurveyResource extends ServerResource {
 
         if (mQuestionId != null) {
             // Get a question by id
-            result = mDb.getKey("strings", "/questions/" + mQuestionId);
+            Question question = null;
+            try {
+                question = mQuestionProvider.get(mQuestionId);
+            } catch (IOException e) {
+                LOG.error("IOException loading question: " + e);
+            }
 
-            if (result == null) {
+            if (question == null) {
                 // 404
                 setStatus(Status.CLIENT_ERROR_NOT_FOUND);
                 return null;
             }
+
+            JacksonRepresentation<Question> rep = new JacksonRepresentation<>(question);
+            rep.setObjectMapper(MAPPER);
+            return rep;
         }
 
         return new StringRepresentation(result);
@@ -85,7 +99,8 @@ public class SurveyResource extends ServerResource {
 
     private Map<?, ?> getQuestionsSummary() {
         try {
-            String json = mDb.getKey("strings", "/questions");
+            // TODO: This could be better. Quick fix for provider support.
+            String json = mStringProvider.get("/questions");
 
             if (json != null) {
                 return MAPPER.readValue(json, Map.class);
diff --git a/src/com/p4square/grow/backend/resources/SurveyResultsResource.java b/src/com/p4square/grow/backend/resources/SurveyResultsResource.java
index 404ccec..7c15cfd 100644
--- a/src/com/p4square/grow/backend/resources/SurveyResultsResource.java
+++ b/src/com/p4square/grow/backend/resources/SurveyResultsResource.java
@@ -4,12 +4,10 @@
 
 package com.p4square.grow.backend.resources;
 
+import java.io.IOException;
 import java.util.Map;
 import java.util.HashMap;
 
-import com.netflix.astyanax.model.Column;
-import com.netflix.astyanax.model.ColumnList;
-
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 import org.restlet.data.MediaType;
@@ -21,12 +19,12 @@ import org.restlet.resource.ServerResource;
 import org.apache.log4j.Logger;
 
 import com.p4square.grow.backend.GrowBackend;
-import com.p4square.grow.backend.db.CassandraDatabase;
 import com.p4square.grow.model.Answer;
 import com.p4square.grow.model.Question;
 import com.p4square.grow.model.RecordedAnswer;
 import com.p4square.grow.model.Score;
 import com.p4square.grow.model.UserRecord;
+import com.p4square.grow.provider.CollectionProvider;
 import com.p4square.grow.provider.Provider;
 
 
@@ -44,7 +42,7 @@ public class SurveyResultsResource extends ServerResource {
         ASSESSMENT, ANSWER
     }
 
-    private CassandraDatabase mDb;
+    private CollectionProvider<String, String, String> mAnswerProvider;
     private Provider<String, Question> mQuestionProvider;
     private Provider<String, UserRecord> mUserRecordProvider;
 
@@ -57,7 +55,7 @@ public class SurveyResultsResource extends ServerResource {
         super.doInit();
 
         final GrowBackend backend = (GrowBackend) getApplication();
-        mDb = backend.getDatabase();
+        mAnswerProvider = backend.getAnswerProvider();
         mQuestionProvider = backend.getQuestionProvider();
         mUserRecordProvider = backend.getUserRecordProvider();
 
@@ -75,27 +73,33 @@ public class SurveyResultsResource extends ServerResource {
      */
     @Override
     protected Representation get() {
-        String result = null;
-
-        switch (mRequestType) {
-            case ANSWER:
-                result = mDb.getKey("assessments", mUserId, mQuestionId);
-                break;
+        try {
+            String result = null;
+
+            switch (mRequestType) {
+                case ANSWER:
+                    result = mAnswerProvider.get(mUserId, mQuestionId);
+                    break;
+
+                case ASSESSMENT:
+                    result = mAnswerProvider.get(mUserId, "summary");
+                    if (result == null || result.length() == 0) {
+                        result = buildAssessment();
+                    }
+                    break;
+            }
 
-            case ASSESSMENT:
-                result = mDb.getKey("assessments", mUserId, "summary");
-                if (result == null) {
-                    result = buildAssessment();
-                }
-                break;
-        }
+            if (result == null) {
+                setStatus(Status.CLIENT_ERROR_NOT_FOUND);
+                return null;
+            }
 
-        if (result == null) {
-            setStatus(Status.CLIENT_ERROR_NOT_FOUND);
+            return new StringRepresentation(result);
+        } catch (IOException e) {
+            LOG.error("IOException getting answer: ", e);
+            setStatus(Status.SERVER_ERROR_INTERNAL);
             return null;
         }
-
-        return new StringRepresentation(result);
     }
 
     /**
@@ -108,9 +112,9 @@ public class SurveyResultsResource extends ServerResource {
         switch (mRequestType) {
             case ANSWER:
                 try {
-                    mDb.putKey("assessments", mUserId, mQuestionId, entity.getText());
-                    mDb.putKey("assessments", mUserId, "lastAnswered", mQuestionId);
-                    mDb.deleteKey("assessments", mUserId, "summary");
+                    mAnswerProvider.put(mUserId, mQuestionId, entity.getText());
+                    mAnswerProvider.put(mUserId, "lastAnswered", mQuestionId);
+                    mAnswerProvider.put(mUserId, "summary", null);
                     success = true;
 
                 } catch (Exception e) {
@@ -143,8 +147,8 @@ public class SurveyResultsResource extends ServerResource {
         switch (mRequestType) {
             case ANSWER:
                 try {
-                    mDb.deleteKey("assessments", mUserId, mQuestionId);
-                    mDb.deleteKey("assessments", mUserId, "summary");
+                    mAnswerProvider.put(mUserId, mQuestionId, null);
+                    mAnswerProvider.put(mUserId, "summary", null);
                     success = true;
 
                 } catch (Exception e) {
@@ -154,7 +158,9 @@ public class SurveyResultsResource extends ServerResource {
 
             case ASSESSMENT:
                 try {
-                    mDb.deleteRow("assessments", mUserId);
+                    mAnswerProvider.put(mUserId, "summary", null);
+                    mAnswerProvider.put(mUserId, "lastAnswered", null);
+                    // TODO Delete answers
 
                     UserRecord record = mUserRecordProvider.get(mUserId);
                     if (record != null) {
@@ -188,48 +194,48 @@ public class SurveyResultsResource extends ServerResource {
     /**
      * This method compiles assessment results.
      */
-    private String buildAssessment() {
+    private String buildAssessment() throws IOException {
         StringBuilder sb = new StringBuilder("{ ");
 
         // Last question answered
-        final String lastAnswered = mDb.getKey("assessments", mUserId, "lastAnswered");
-        if (lastAnswered != null) {
-            sb.append("\"lastAnswered\": \"" + lastAnswered + "\"");
+        final String lastAnswered = mAnswerProvider.get(mUserId, "lastAnswered");
+        if (lastAnswered != null && lastAnswered.length() > 0) {
+            sb.append("\"lastAnswered\": \"" + lastAnswered + "\", ");
         }
 
         // Compute score
-        ColumnList<String> row = mDb.getRow("assessments", mUserId);
-        if (!row.isEmpty()) {
+        Map<String, String> row = mAnswerProvider.query(mUserId);
+        if (row.size() > 0) {
             Score score = new Score();
             boolean scoringDone = false;
             int totalAnswers = 0;
-            for (Column<String> c : row) {
-                if (c.getName().equals("lastAnswered") || c.getName().equals("summary")) {
+            for (Map.Entry<String, String> c : row.entrySet()) {
+                if (c.getKey().equals("lastAnswered") || c.getKey().equals("summary")) {
                     continue;
                 }
 
                 try {
-                    Question question = mQuestionProvider.get(c.getName());
-                    RecordedAnswer userAnswer = MAPPER.readValue(c.getStringValue(), RecordedAnswer.class);
+                    Question question = mQuestionProvider.get(c.getKey());
+                    RecordedAnswer userAnswer = MAPPER.readValue(c.getValue(), RecordedAnswer.class);
 
                     if (question == null) {
-                        LOG.warn("Answer for unknown question: " + c.getName());
+                        LOG.warn("Answer for unknown question: " + c.getKey());
                         continue;
                     }
 
-                    LOG.debug("Scoring questionId: " + c.getName());
+                    LOG.debug("Scoring questionId: " + c.getKey());
                     scoringDone = !question.scoreAnswer(score, userAnswer);
 
                 } catch (Exception e) {
                     LOG.error("Failed to score question: {userid: \"" + mUserId +
-                            "\", questionid:\"" + c.getName() +
-                            "\", userAnswer:\"" + c.getStringValue() + "\"}", e);
+                            "\", questionid:\"" + c.getKey() +
+                            "\", userAnswer:\"" + c.getValue() + "\"}", e);
                 }
 
                 totalAnswers++;
             }
 
-            sb.append(", \"score\":" + score.getScore());
+            sb.append("\"score\":" + score.getScore());
             sb.append(", \"sum\":" + score.getSum());
             sb.append(", \"count\":" + score.getCount());
             sb.append(", \"totalAnswers\":" + totalAnswers);
@@ -240,7 +246,7 @@ public class SurveyResultsResource extends ServerResource {
         String summary = sb.toString();
 
         // Persist summary
-        mDb.putKey("assessments", mUserId, "summary", summary);
+        mAnswerProvider.put(mUserId, "summary", summary);
 
         return summary;
     }
diff --git a/src/com/p4square/grow/backend/resources/TrainingRecordResource.java b/src/com/p4square/grow/backend/resources/TrainingRecordResource.java
index 3d9d67f..b316b75 100644
--- a/src/com/p4square/grow/backend/resources/TrainingRecordResource.java
+++ b/src/com/p4square/grow/backend/resources/TrainingRecordResource.java
@@ -11,9 +11,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.HashMap;
 
-import com.netflix.astyanax.model.Column;
-import com.netflix.astyanax.model.ColumnList;
-
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 import org.restlet.data.MediaType;
@@ -27,16 +24,17 @@ import org.restlet.ext.jackson.JacksonRepresentation;
 import org.apache.log4j.Logger;
 
 import com.p4square.grow.backend.GrowBackend;
-import com.p4square.grow.backend.db.CassandraDatabase;
 
 import com.p4square.grow.model.Chapter;
 import com.p4square.grow.model.Playlist;
 import com.p4square.grow.model.VideoRecord;
 import com.p4square.grow.model.TrainingRecord;
 
+import com.p4square.grow.provider.CollectionProvider;
+import com.p4square.grow.provider.JsonEncodedProvider;
 import com.p4square.grow.provider.Provider;
+import com.p4square.grow.provider.ProvidesAssessments;
 import com.p4square.grow.provider.ProvidesTrainingRecords;
-import com.p4square.grow.provider.JsonEncodedProvider;
 
 import com.p4square.grow.model.Score;
 
@@ -52,8 +50,8 @@ public class TrainingRecordResource extends ServerResource {
         SUMMARY, VIDEO
     }
 
-    private CassandraDatabase mDb;
     private Provider<String, TrainingRecord> mTrainingRecordProvider;
+    private CollectionProvider<String, String, String> mAnswerProvider;
 
     private RequestType mRequestType;
     private String mUserId;
@@ -64,8 +62,8 @@ public class TrainingRecordResource extends ServerResource {
     public void doInit() {
         super.doInit();
 
-        mDb = ((GrowBackend) getApplication()).getDatabase();
         mTrainingRecordProvider = ((ProvidesTrainingRecords) getApplication()).getTrainingRecordProvider();
+        mAnswerProvider = ((ProvidesAssessments) getApplication()).getAnswerProvider();
 
         mUserId = getAttribute("userId");
         mVideoId = getAttribute("videoId");
@@ -184,7 +182,7 @@ public class TrainingRecordResource extends ServerResource {
         double assessedScore = 0;
 
         try {
-            String summaryString = mDb.getKey("assessments", userId, "summary");
+            String summaryString = mAnswerProvider.get(userId, "summary");
             if (summaryString == null) {
                 LOG.warn("Asked to create training record for unassessed user " + userId);
                 return;
diff --git a/src/com/p4square/grow/backend/resources/TrainingResource.java b/src/com/p4square/grow/backend/resources/TrainingResource.java
index 85d08c1..6efdfab 100644
--- a/src/com/p4square/grow/backend/resources/TrainingResource.java
+++ b/src/com/p4square/grow/backend/resources/TrainingResource.java
@@ -4,8 +4,8 @@
 
 package com.p4square.grow.backend.resources;
 
-import com.netflix.astyanax.model.Column;
-import com.netflix.astyanax.model.ColumnList;
+import java.io.IOException;
+import java.util.Map;
 
 import org.restlet.data.Status;
 import org.restlet.resource.ServerResource;
@@ -17,16 +17,16 @@ import org.apache.log4j.Logger;
 import com.p4square.grow.backend.GrowBackend;
 import com.p4square.grow.backend.db.CassandraDatabase;
 
+import com.p4square.grow.provider.CollectionProvider;
 /**
  * This resource returns a listing of training items for a particular level.
  *
  * @author Jesse Morgan <jesse@jesterpm.net>
  */
 public class TrainingResource extends ServerResource {
-    private final static Logger cLog = Logger.getLogger(TrainingResource.class);
+    private final static Logger LOG = Logger.getLogger(TrainingResource.class);
 
-    private GrowBackend mBackend;
-    private CassandraDatabase mDb;
+    private CollectionProvider<String, String, String> mVideoProvider;
 
     private String mLevel;
     private String mVideoId;
@@ -35,8 +35,8 @@ public class TrainingResource extends ServerResource {
     public void doInit() {
         super.doInit();
 
-        mBackend = (GrowBackend) getApplication();
-        mDb = mBackend.getDatabase();
+        GrowBackend backend = (GrowBackend) getApplication();
+        mVideoProvider = backend.getVideoProvider();
 
         mLevel = getAttribute("level");
         mVideoId = getAttribute("videoId");
@@ -54,35 +54,44 @@ public class TrainingResource extends ServerResource {
             return null;
         }
 
-        if (mVideoId == null) {
-            // Get all videos
-            ColumnList<String> row = mDb.getRow("strings", "/training/" + mLevel);
-            if (!row.isEmpty()) {
-                StringBuilder sb = new StringBuilder("{ \"level\": \"" + mLevel + "\"");
-                sb.append(", \"videos\": [");
-                boolean first = true;
-                for (Column<String> c : row) {
-                    if (!first) {
-                        sb.append(", ");
+        try {
+            if (mVideoId == null) {
+                // Get all videos
+                // TODO: This could be improved, but this is the quickest way to get
+                // providers working.
+                Map<String, String> videos = mVideoProvider.query(mLevel);
+                if (videos.size() > 0) {
+                    StringBuilder sb = new StringBuilder("{ \"level\": \"" + mLevel + "\"");
+                    sb.append(", \"videos\": [");
+                    boolean first = true;
+                    for (String value : videos.values()) {
+                        if (!first) {
+                            sb.append(", ");
+                        }
+                        sb.append(value);
+                        first = false;
                     }
-                    sb.append(c.getStringValue());
-                    first = false;
+                    sb.append("] }");
+                    result = sb.toString();
                 }
-                sb.append("] }");
-                result = sb.toString();
+
+            } else {
+                // Get single video
+                result = mVideoProvider.get(mLevel, mVideoId);
             }
 
-        } else {
-            // Get single video
-            result = mDb.getKey("strings", "/training/" + mLevel, mVideoId);
-        }
+            if (result == null) {
+                // 404
+                setStatus(Status.CLIENT_ERROR_NOT_FOUND);
+                return null;
+            }
 
-        if (result == null) {
-            // 404
-            setStatus(Status.CLIENT_ERROR_NOT_FOUND);
+            return new StringRepresentation(result);
+
+        } catch (IOException e) {
+            LOG.error("IOException fetch video: " + e.getMessage(), e);
+            setStatus(Status.SERVER_ERROR_INTERNAL);
             return null;
         }
-
-        return new StringRepresentation(result);
     }
 }
diff --git a/src/com/p4square/grow/provider/DelegateCollectionProvider.java b/src/com/p4square/grow/provider/DelegateCollectionProvider.java
new file mode 100644
index 0000000..e17af87
--- /dev/null
+++ b/src/com/p4square/grow/provider/DelegateCollectionProvider.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.provider;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ *
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+public abstract class DelegateCollectionProvider<C, DC, K, DK, V>
+    implements CollectionProvider<C, K, V> {
+
+    private CollectionProvider<DC, DK, V> mProvider;
+
+    public DelegateCollectionProvider(final CollectionProvider<DC, DK, V> provider) {
+        mProvider = provider;
+    }
+
+    public V get(C collection, K key) throws IOException {
+        return mProvider.get(makeCollectionKey(collection), makeKey(key));
+    }
+
+    public Map<K, V> query(C collection) throws IOException {
+        return query(collection, -1);
+    }
+
+    public Map<K, V> query(C collection, int limit) throws IOException {
+        Map<DK, V> delegateResult =  mProvider.query(makeCollectionKey(collection), limit);
+        Map<K, V> result = new HashMap<>();
+        for (Map.Entry<DK, V> entry : delegateResult.entrySet()) {
+            result.put(unmakeKey(entry.getKey()), entry.getValue());
+        }
+
+        return result;
+    }
+
+    public void put(C collection, K key, V obj) throws IOException {
+        mProvider.put(makeCollectionKey(collection), makeKey(key), obj);
+    }
+
+    /**
+     * Make a collection key for the delegated provider.
+     *
+     * @param input The pre-transform key.
+     * @return the post-transform key.
+     */
+    protected abstract DC makeCollectionKey(final C input);
+
+    /**
+     * Make a key for the delegated provider.
+     *
+     * @param input The pre-transform key.
+     * @return the post-transform key.
+     */
+    protected abstract DK makeKey(final K input);
+
+    /**
+     * Transform a key for the delegated provider to an input key.
+     *
+     * @param input The post-transform key.
+     * @return the pre-transform key.
+     */
+    protected abstract K unmakeKey(final DK input);
+}
diff --git a/src/com/p4square/grow/provider/DelegateProvider.java b/src/com/p4square/grow/provider/DelegateProvider.java
index 66c5666..42dcc63 100644
--- a/src/com/p4square/grow/provider/DelegateProvider.java
+++ b/src/com/p4square/grow/provider/DelegateProvider.java
@@ -31,10 +31,10 @@ public abstract class DelegateProvider<K, D, V> implements Provider<K, V> {
     }
 
     /**
-     * Make a Key for questionId.
+     * Make a Key for the delegated provider.
      *
-     * @param questionId The question id.
-     * @return a key for questionId.
+     * @param input The pre-transform key.
+     * @return the post-transform key.
      */
     protected abstract D makeKey(final K input);
 }
diff --git a/src/com/p4square/grow/provider/JsonEncodedProvider.java b/src/com/p4square/grow/provider/JsonEncodedProvider.java
index 7ae3f71..7651443 100644
--- a/src/com/p4square/grow/provider/JsonEncodedProvider.java
+++ b/src/com/p4square/grow/provider/JsonEncodedProvider.java
@@ -25,8 +25,8 @@ public abstract class JsonEncodedProvider<V> {
         MAPPER.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
     }
 
-    private final Class<V> mClazz;
-    private final JavaType mType;
+    protected final Class<V> mClazz;
+    protected final JavaType mType;
 
     public JsonEncodedProvider(Class<V> clazz) {
         mClazz = clazz;
diff --git a/src/com/p4square/grow/provider/ProvidesAssessments.java b/src/com/p4square/grow/provider/ProvidesAssessments.java
new file mode 100644
index 0000000..62ba8f6
--- /dev/null
+++ b/src/com/p4square/grow/provider/ProvidesAssessments.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.provider;
+
+import com.p4square.grow.model.RecordedAnswer;
+
+/**
+ * 
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+public interface ProvidesAssessments {
+    /**
+     * Provides a collection of user assessments.
+     * The collection key is the user id.
+     * The key is the question id.
+     */
+    CollectionProvider<String, String, String> getAnswerProvider();
+}
diff --git a/src/com/p4square/grow/provider/ProvidesStrings.java b/src/com/p4square/grow/provider/ProvidesStrings.java
new file mode 100644
index 0000000..5d9976e
--- /dev/null
+++ b/src/com/p4square/grow/provider/ProvidesStrings.java
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.provider;
+
+/**
+ * Indicates the ability to provide a String provider.
+ *
+ * Strings are typically configuration settings stored as a String.
+ *
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+public interface ProvidesStrings {
+    /**
+     * @return A Provider of Questions keyed by question id.
+     */
+    Provider<String, String> getStringProvider();
+}
\ No newline at end of file
diff --git a/src/com/p4square/grow/provider/ProvidesTrainingRecords.java b/src/com/p4square/grow/provider/ProvidesTrainingRecords.java
index 27ffa3e..586e649 100644
--- a/src/com/p4square/grow/provider/ProvidesTrainingRecords.java
+++ b/src/com/p4square/grow/provider/ProvidesTrainingRecords.java
@@ -4,7 +4,10 @@
 
 package com.p4square.grow.provider;
 
+import java.io.IOException;
+
 import com.p4square.grow.model.TrainingRecord;
+import com.p4square.grow.model.Playlist;
 
 /**
  * Indicates the ability to provide a TrainingRecord Provider.
@@ -16,4 +19,9 @@ public interface ProvidesTrainingRecords {
      * @return A Provider of Questions keyed by question id.
      */
     Provider<String, TrainingRecord> getTrainingRecordProvider();
+
+    /**
+     * @return the Default Playlist.
+     */
+    Playlist getDefaultPlaylist() throws IOException;
 }
diff --git a/src/com/p4square/grow/provider/ProvidesVideos.java b/src/com/p4square/grow/provider/ProvidesVideos.java
new file mode 100644
index 0000000..3d055d3
--- /dev/null
+++ b/src/com/p4square/grow/provider/ProvidesVideos.java
@@ -0,0 +1,16 @@
+/*
+ * Copyright 2014 Jesse Morgan
+ */
+
+package com.p4square.grow.provider;
+
+/**
+ * 
+ * @author Jesse Morgan <jesse@jesterpm.net>
+ */
+public interface ProvidesVideos {
+    /**
+     * @return A Provider of Questions keyed by question id.
+     */
+    CollectionProvider<String, String, String> getVideoProvider();
+}