Merge pull request #77 from m-chrzan/stanik

Stanik

10 files changed, 350 insertions, 1 deletions

diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/GetStateMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/GetStateMessage.java
new file mode 100644
index 0000000..63392e8
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/GetStateMessage.java
@@ -0,0 +1,22 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+
+public class GetStateMessage extends StanikMessage {
+    private ModuleType requestingModule;
+    private long requestId;
+
+    public GetStateMessage(String messageId, long timestamp, ModuleType requestingModule, long requestId) {
+        super(messageId, timestamp, Type.GET_STATE);
+        this.requestingModule = requestingModule;
+        this.requestId = requestId;
+    }
+
+    public ModuleType getRequestingModule() {
+        return requestingModule;
+    }
+
+    public long getRequestId() {
+        return requestId;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/ResponseMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/ResponseMessage.java
new file mode 100644
index 0000000..02b3337
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/ResponseMessage.java
@@ -0,0 +1,31 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+
+public abstract class ResponseMessage extends AgentMessage {
+    public enum Type {
+        STATE
+    }
+
+    Type type;
+    long requestId;
+
+    public ResponseMessage(String messageId, ModuleType destinationModule, long timestamp, Type type, long requestId) {
+        super(messageId, destinationModule, timestamp);
+        this.type = type;
+        this.requestId = requestId;
+    }
+
+    public void callMe(Module module) throws InterruptedException, Module.InvalidMessageType {
+        module.handleTyped(this);
+    }
+
+    public long getRequestId() {
+        return requestId;
+    }
+
+    public Type getType() {
+        return type;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StanikMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StanikMessage.java
new file mode 100644
index 0000000..b23f6e0
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StanikMessage.java
@@ -0,0 +1,27 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.Module;
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+
+public abstract class StanikMessage extends AgentMessage {
+    public enum Type {
+        GET_STATE,
+        UPDATE_ATTRIBUTES,
+        UPDATE_QUERIES
+    }
+
+    private Type type;
+
+    public StanikMessage(String messageId, long timestamp, Type type) {
+        super(messageId, ModuleType.STATE, timestamp);
+        this.type = type;
+    }
+
+    public Type getType() {
+        return type;
+    }
+
+    public void callMe(Module module) throws InterruptedException, Module.InvalidMessageType {
+        module.handleTyped(this);
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StateMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StateMessage.java
new file mode 100644
index 0000000..f7f490b
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/StateMessage.java
@@ -0,0 +1,29 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import java.util.Map;
+import java.util.Map.Entry;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+import pl.edu.mimuw.cloudatlas.model.Attribute;
+import pl.edu.mimuw.cloudatlas.model.ValueQuery;
+import pl.edu.mimuw.cloudatlas.model.ValueTime;
+import pl.edu.mimuw.cloudatlas.model.ZMI;
+
+public class StateMessage extends ResponseMessage {
+    private ZMI zmi;
+    private Map<Attribute, Entry<ValueQuery, ValueTime>> queries;
+
+    public StateMessage(String messageId, ModuleType destinationModule, long timestamp, long requestId, ZMI zmi, Map<Attribute, Entry<ValueQuery, ValueTime>> queries) {
+        super(messageId, destinationModule, timestamp, Type.STATE, requestId);
+        this.zmi = zmi;
+        this.queries = queries;
+    }
+
+    public ZMI getZMI() {
+        return zmi;
+    }
+
+    public Map<Attribute, Entry<ValueQuery, ValueTime>> getQueries() {
+        return queries;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateAttributesMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateAttributesMessage.java
new file mode 100644
index 0000000..7e41631
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateAttributesMessage.java
@@ -0,0 +1,23 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import pl.edu.mimuw.cloudatlas.agent.modules.ModuleType;
+import pl.edu.mimuw.cloudatlas.model.AttributesMap;
+
+public class UpdateAttributesMessage extends StanikMessage {
+    private String pathName;
+    private AttributesMap attributes;
+
+    public UpdateAttributesMessage(String messageId, long timestamp, String pathName, AttributesMap attributes) {
+        super(messageId, timestamp, Type.UPDATE_ATTRIBUTES);
+        this.pathName = pathName;
+        this.attributes = attributes;
+    }
+
+    public String getPathName() {
+        return pathName;
+    }
+
+    public AttributesMap getAttributes() {
+        return attributes;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateQueriesMessage.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateQueriesMessage.java
new file mode 100644
index 0000000..58ad55a
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/messages/UpdateQueriesMessage.java
@@ -0,0 +1,21 @@
+package pl.edu.mimuw.cloudatlas.agent.messages;
+
+import java.util.Map;
+import java.util.Map.Entry;
+
+import pl.edu.mimuw.cloudatlas.model.Attribute;
+import pl.edu.mimuw.cloudatlas.model.ValueQuery;
+import pl.edu.mimuw.cloudatlas.model.ValueTime;
+
+public class UpdateQueriesMessage extends StanikMessage {
+    private Map<Attribute, Entry<ValueQuery, ValueTime>> queries;
+
+    public UpdateQueriesMessage(String messageId, long timestamp, Map<Attribute, Entry<ValueQuery, ValueTime>> queries) {
+        super(messageId, timestamp, Type.UPDATE_QUERIES);
+        this.queries = queries;
+    }
+
+    public Map<Attribute, Entry<ValueQuery, ValueTime>> getQueries() {
+        return queries;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
index a50a95f..d0bf083 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Module.java
@@ -3,7 +3,9 @@ package pl.edu.mimuw.cloudatlas.agent.modules;
 import pl.edu.mimuw.cloudatlas.agent.Executor;
 import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
 import pl.edu.mimuw.cloudatlas.agent.messages.TimerSchedulerMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.ResponseMessage;
 import pl.edu.mimuw.cloudatlas.agent.messages.RMIMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.StanikMessage;
 
 /*
  * A Module is a (potentially stateful) event handler.
@@ -34,6 +36,14 @@ public abstract class Module {
         throw new InvalidMessageType("Got an RMIMessage in module " + moduleType.toString());
     }
 
+    public void handleTyped(StanikMessage message) throws InterruptedException, InvalidMessageType {
+        throw new InvalidMessageType("Got a StanikMessage in module " + moduleType.toString());
+    }
+
+    public void handleTyped(ResponseMessage message) throws InterruptedException, InvalidMessageType {
+        throw new InvalidMessageType("Got a ResponseMessage in module " + moduleType.toString());
+    }
+
     public void setExecutor(Executor executor) {
         this.executor = executor;
     }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java
index ff4a92e..d221f06 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/ModuleType.java
@@ -8,5 +8,7 @@ public enum ModuleType {
     GOSSIP_IN,
     GOSSIP_OUT,
     STATE,
-    QUERY
+    QUERY,
+    // for testing
+    TEST
 }
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Stanik.java b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Stanik.java
new file mode 100644
index 0000000..e8721b3
--- /dev/null
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/agent/modules/Stanik.java
@@ -0,0 +1,167 @@
+package pl.edu.mimuw.cloudatlas.agent.modules;
+
+import java.util.Iterator;
+import java.util.HashMap;
+import java.util.Map.Entry;
+
+import pl.edu.mimuw.cloudatlas.agent.messages.AgentMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.GetStateMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.StateMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.StanikMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.UpdateAttributesMessage;
+import pl.edu.mimuw.cloudatlas.agent.messages.UpdateQueriesMessage;
+import pl.edu.mimuw.cloudatlas.model.Attribute;
+import pl.edu.mimuw.cloudatlas.model.AttributesMap;
+import pl.edu.mimuw.cloudatlas.model.PathName;
+import pl.edu.mimuw.cloudatlas.model.Type;
+import pl.edu.mimuw.cloudatlas.model.TypePrimitive;
+import pl.edu.mimuw.cloudatlas.model.Value;
+import pl.edu.mimuw.cloudatlas.model.ValueBoolean;
+import pl.edu.mimuw.cloudatlas.model.ValueQuery;
+import pl.edu.mimuw.cloudatlas.model.ValueString;
+import pl.edu.mimuw.cloudatlas.model.ValueTime;
+import pl.edu.mimuw.cloudatlas.model.ZMI;
+
+public class Stanik extends Module {
+    private class InvalidUpdateAttributesMessage extends Exception {
+        public InvalidUpdateAttributesMessage(String message) {
+            super(message);
+        }
+    }
+
+    private ZMI hierarchy;
+    private HashMap<Attribute, Entry<ValueQuery, ValueTime>> queries;
+
+    public Stanik() {
+        super(ModuleType.STATE);
+        hierarchy = new ZMI();
+        queries = new HashMap<Attribute, Entry<ValueQuery, ValueTime>>();
+        hierarchy.getAttributes().add("timestamp", new ValueTime(0l));
+    }
+
+    public void handleTyped(StanikMessage message) throws InterruptedException, InvalidMessageType {
+        switch(message.getType()) {
+            case GET_STATE:
+                handleGetState((GetStateMessage) message);
+                break;
+            case UPDATE_ATTRIBUTES:
+                handleUpdateAttributes((UpdateAttributesMessage) message);
+                break;
+            case UPDATE_QUERIES:
+                handleUpdateQueries((UpdateQueriesMessage) message);
+                break;
+            default:
+                throw new InvalidMessageType("This type of message cannot be handled by Stanik");
+        }
+    }
+
+    public void handleGetState(GetStateMessage message) throws InterruptedException {
+        StateMessage response = new StateMessage("", message.getRequestingModule(), 0, message.getRequestId(), hierarchy.clone(), (HashMap<Attribute, Entry<ValueQuery, ValueTime>>) queries.clone());
+        sendMessage(response);
+    }
+
+    public void handleUpdateAttributes(UpdateAttributesMessage message) {
+        try {
+            validateUpdateAttributesMessage(message);
+            addMissingZones(new PathName(message.getPathName()));
+            ZMI zone = hierarchy.findDescendant(message.getPathName());
+            AttributesMap attributes = zone.getAttributes();
+            if (valueLower(attributes.get("timestamp"), message.getAttributes().get("timestamp"))) {
+                transferAttributes(message.getAttributes(), attributes);
+            } else {
+                System.out.println("DEBUG: not applying update with older attributes");
+            }
+        } catch (InvalidUpdateAttributesMessage e) {
+            System.out.println("ERROR: invalid UpdateAttributesMessage " + e.getMessage());
+        } catch (ZMI.NoSuchZoneException e) {
+            System.out.println("ERROR: zone should exist after being added");
+        }
+    }
+
+    public void handleUpdateQueries(UpdateQueriesMessage message) {
+        for (Entry<Attribute, Entry<ValueQuery, ValueTime>> entry : message.getQueries().entrySet()) {
+            Attribute attribute = entry.getKey();
+            ValueTime timestamp = entry.getValue().getValue();
+            Entry<ValueQuery, ValueTime> currentTimestampedQuery = queries.get(attribute);
+            if (currentTimestampedQuery == null || valueLower(currentTimestampedQuery.getValue(), timestamp)) {
+                queries.put(entry.getKey(), entry.getValue());
+            }
+        }
+    }
+
+    private boolean valueLower(Value a, Value b) {
+        return ((ValueBoolean) a.isLowerThan(b)).getValue();
+    }
+
+    private void validateUpdateAttributesMessage(UpdateAttributesMessage message) throws InvalidUpdateAttributesMessage {
+        validateZoneName(message);
+        validateHasTimeStamp(message);
+    }
+
+    private void validateZoneName(UpdateAttributesMessage message) throws InvalidUpdateAttributesMessage {
+        Value name = message.getAttributes().getOrNull("name");
+        if (message.getPathName().equals("/")) {
+            if (name != null && !name.isNull()) {
+                throw new InvalidUpdateAttributesMessage("The root zone should have a null name");
+            }
+        } else {
+            if (valueNonNullOfType(name, TypePrimitive.STRING)) {
+                ValueString nameString = (ValueString) name;
+                String expectedName = (new PathName(message.getPathName())).getSingletonName();
+                if (!nameString.getValue().equals(expectedName)) {
+                    throw new InvalidUpdateAttributesMessage("The zone's name attribute should match its path name");
+                }
+            } else {
+                throw new InvalidUpdateAttributesMessage("Zone attributes should have a name attribute of type String");
+            }
+        }
+    }
+
+    private void validateHasTimeStamp(UpdateAttributesMessage message) throws InvalidUpdateAttributesMessage {
+        if (!valueNonNullOfType(message.getAttributes().getOrNull("timestamp"), TypePrimitive.TIME)) {
+            throw new InvalidUpdateAttributesMessage("Zone attriutes should have a timestamp attribute of type Time");
+        }
+    }
+
+    private boolean valueNonNullOfType(Value value, Type type) {
+        return value != null && !value.isNull() && value.getType().isCompatible(type);
+    }
+
+    private void transferAttributes(AttributesMap fromAttributes, AttributesMap toAttributes) {
+        Iterator<Entry<Attribute, Value>> iterator = toAttributes.iterator();
+        while (iterator.hasNext()) {
+            Entry<Attribute, Value> entry = iterator.next();
+            Attribute attribute = entry.getKey();
+            Value newValue = fromAttributes.getOrNull(attribute);
+            if (newValue == null) {
+                iterator.remove();
+            }
+        }
+        for (Entry<Attribute, Value> entry : fromAttributes) {
+            toAttributes.addOrChange(entry.getKey(), entry.getValue());
+        }
+    }
+
+    private void addMissingZones(PathName path) {
+        try {
+            if (!hierarchy.descendantExists(path)) {
+                addMissingZones(path.levelUp());
+                ZMI parent = hierarchy.findDescendant(path.levelUp());
+                ZMI newSon = new ZMI(parent);
+                newSon.getAttributes().add("name", new ValueString(path.getSingletonName()));
+                newSon.getAttributes().add("timestamp", new ValueTime(0l));
+                parent.addSon(newSon);
+            }
+        } catch (ZMI.NoSuchZoneException e) {
+            System.out.println("ERROR: zone should exist after being added");
+        }
+    }
+
+    public ZMI getHierarchy() {
+        return hierarchy;
+    }
+
+    public HashMap<Attribute, Entry<ValueQuery, ValueTime>> getQueries() {
+        return queries;
+    }
+}
diff --git a/src/main/java/pl/edu/mimuw/cloudatlas/model/ZMI.java b/src/main/java/pl/edu/mimuw/cloudatlas/model/ZMI.java
index 7f2f604..54fbf43 100644
--- a/src/main/java/pl/edu/mimuw/cloudatlas/model/ZMI.java
+++ b/src/main/java/pl/edu/mimuw/cloudatlas/model/ZMI.java
@@ -111,6 +111,23 @@ public class ZMI implements Cloneable, Serializable {
         return descendant;
     }
 
+    public boolean descendantExists(PathName path) {
+        try {
+            findDescendant(path);
+            return true;
+        } catch (NoSuchZoneException e) {
+            return false;
+        }
+    }
+
+    /*
+     * Convenient version of findDescendant that takes String representation of
+     * path.
+     */
+    public ZMI findDescendant(String pathString) throws NoSuchZoneException {
+        return findDescendant(new PathName(pathString));
+    }
+
     /**
      * Gets the list of sons of this ZMI. Modifying a value in the returned list will cause an exception.
      *