Implement client registration and metrics.

Adds implementation where the client register at startup
and sends metrics to the server regulary.

implements #3

README.md

@@ -11,7 +11,14 @@ Spring or Guice to manage this.
 
 You create a new instance with the following command:
 ```java
+
+UnleashConfig unleashConfig = new UnleashConfig.Builder()
+            .appName("java-test")
+            .instanceId("instance x")
+            .unleashAPI("http://unleash.herokuapp.com")
+            .build();
 URI unleashServer = URI.create("http://unleash.herokuapp.com/features")
+
 Unleash unleash = new DefaultUnleash(unleashServer);
 ```
 

src/main/java/no/finn/unleash/DefaultUnleash.java

@@ -1,33 +1,48 @@
 package no.finn.unleash;
 
-import java.net.URI;
 import java.util.HashMap;
 import java.util.Map;
+
+import no.finn.unleash.metric.UnleashMetricService;
+import no.finn.unleash.metric.UnleashMetricServiceImpl;
 import no.finn.unleash.repository.FeatureToggleRepository;
 import no.finn.unleash.repository.ToggleBackupHandlerFile;
 import no.finn.unleash.repository.HttpToggleFetcher;
 import no.finn.unleash.repository.ToggleRepository;
 import no.finn.unleash.strategy.DefaultStrategy;
 import no.finn.unleash.strategy.Strategy;
 import no.finn.unleash.strategy.UnknownStrategy;
+import no.finn.unleash.util.UnleashConfig;
+import no.finn.unleash.util.UnleashScheduledExecutor;
+import no.finn.unleash.util.UnleashScheduledExecutorImpl;
 
 public final class DefaultUnleash implements Unleash {
     private static final DefaultStrategy DEFAULT_STRATEGY = new DefaultStrategy();
     private static final UnknownStrategy UNKNOWN_STRATEGY = new UnknownStrategy();
+    private static final UnleashScheduledExecutor unleashScheduledExecutor = new UnleashScheduledExecutorImpl();
 
+    private final UnleashMetricService metricService;
     private final ToggleRepository toggleRepository;
     private final Map<String, Strategy> strategyMap;
 
-    public DefaultUnleash(URI unleashServer, Strategy... strategies) {
-        this(new FeatureToggleRepository(
-                        new HttpToggleFetcher(unleashServer),
-                        new ToggleBackupHandlerFile()),
-                strategies);
+
+    private static FeatureToggleRepository defaultToggleRepository(UnleashConfig unleashConfig) {
+        return new FeatureToggleRepository(
+                unleashConfig,
+                unleashScheduledExecutor,
+                new HttpToggleFetcher(unleashConfig),
+                new ToggleBackupHandlerFile());
     }
 
-    public DefaultUnleash(ToggleRepository toggleRepository, Strategy... strategies) {
+    public DefaultUnleash(UnleashConfig unleashConfig, Strategy... strategies) {
+        this(unleashConfig, defaultToggleRepository(unleashConfig), strategies);
+    }
+
+    public DefaultUnleash(UnleashConfig unleashConfig, ToggleRepository toggleRepository, Strategy... strategies) {
         this.toggleRepository = toggleRepository;
         this.strategyMap = buildStrategyMap(strategies);
+        this.metricService = new UnleashMetricServiceImpl(unleashConfig, unleashScheduledExecutor);
+        metricService.register(strategyMap.keySet());
     }
 
     @Override
@@ -37,18 +52,22 @@ public boolean isEnabled(final String toggleName) {
 
     @Override
     public boolean isEnabled(final String toggleName, final boolean defaultSetting) {
+        boolean enabled = false;
         FeatureToggle featureToggle = toggleRepository.getToggle(toggleName);
 
         if (featureToggle == null) {
-            return defaultSetting;
+            enabled = defaultSetting;
         } else if(!featureToggle.isEnabled()) {
-            return false;
+            enabled = false;
+        } else {
+            enabled = featureToggle.getStrategies().stream()
+                    .filter(as -> getStrategy(as.getName()).isEnabled(as.getParameters()))
+                    .findFirst()
+                    .isPresent();
         }
 
-        return featureToggle.getStrategies().stream()
-                .filter(as -> getStrategy(as.getName()).isEnabled(as.getParameters()))
-                .findFirst()
-                .isPresent();
+        metricService.count(toggleName, enabled);
+        return enabled;
     }
 
     private Map<String, Strategy> buildStrategyMap(Strategy[] strategies) {

src/main/java/no/finn/unleash/metric/ClientMetrics.java

@@ -0,0 +1,28 @@
+package no.finn.unleash.metric;
+
+import no.finn.unleash.util.UnleashConfig;
+
+class ClientMetrics {
+
+    private final String appName;
+    private final String instanceId;
+    private final MetricsBucket bucket;
+
+    ClientMetrics(UnleashConfig config, MetricsBucket bucket) {
+        this.appName = config.getAppName();
+        this.instanceId = config.getInstanceId();
+        this.bucket = bucket;
+    }
+
+    public String getAppName() {
+        return appName;
+    }
+
+    public String getInstanceId() {
+        return instanceId;
+    }
+
+    public MetricsBucket getBucket() {
+        return bucket;
+    }
+}

src/main/java/no/finn/unleash/metric/ClientRegistration.java

@@ -0,0 +1,42 @@
+ package no.finn.unleash.metric;
+
+ import no.finn.unleash.util.UnleashConfig;
+
+ import java.time.LocalDateTime;
+ import java.util.Set;
+
+class ClientRegistration {
+    private final String appName;
+    private final String instanceId;
+    private final Set<String> strategies;
+    private final LocalDateTime started;
+    private final long interval;
+
+    ClientRegistration(UnleashConfig config, LocalDateTime started, Set<String> strategies) {
+        this.appName = config.getAppName();
+        this.instanceId = config.getInstanceId();
+        this.started = started;
+        this.strategies = strategies;
+        this.interval = config.getSendMetricsInterval();
+    }
+
+    public String getAppName() {
+        return appName;
+    }
+
+    public String getInstanceId() {
+        return instanceId;
+    }
+
+    public Set<String> getStrategies() {
+        return strategies;
+    }
+
+    public LocalDateTime getStarted() {
+        return started;
+    }
+
+    public long getInterval() {
+        return interval;
+    }
+}

src/main/java/no/finn/unleash/metric/MetricsBucket.java

@@ -0,0 +1,43 @@
+package no.finn.unleash.metric;
+
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.HashMap;
+import java.util.Map;
+
+class MetricsBucket {
+    private final Map<String, ToggleCount> toggles;
+    private final LocalDateTime start;
+    private LocalDateTime stop;
+
+    MetricsBucket() {
+        this.start = LocalDateTime.now(ZoneId.of("UTC"));
+        this.toggles = new HashMap<>();
+    }
+
+    void registerCount(String toggleName, boolean active) {
+        if(toggles.containsKey(toggleName)) {
+            toggles.get(toggleName).register(active);
+        } else {
+            ToggleCount counter = new ToggleCount();
+            counter.register(active);
+            toggles.put(toggleName, counter);
+        }
+    }
+
+    void end() {
+        this.stop = LocalDateTime.now(ZoneId.of("UTC"));
+    }
+
+    public Map<String, ToggleCount> getToggles() {
+        return toggles;
+    }
+
+    public LocalDateTime getStart() {
+        return start;
+    }
+
+    public LocalDateTime getStop() {
+        return stop;
+    }
+}

src/main/java/no/finn/unleash/metric/ToggleCount.java

@@ -0,0 +1,27 @@
+package no.finn.unleash.metric;
+
+class ToggleCount {
+    private long yes;
+    private long no;
+
+    public ToggleCount() {
+        this.yes = 0;
+        this.no = 0;
+    }
+
+    public void register(boolean active) {
+        if(active) {
+            yes++;
+        } else {
+            no++;
+        }
+    }
+
+    public long getYes() {
+        return yes;
+    }
+
+    public long getNo() {
+        return no;
+    }
+}

src/main/java/no/finn/unleash/metric/UnleashMetricService.java

@@ -0,0 +1,8 @@
+package no.finn.unleash.metric;
+
+import java.util.Set;
+
+public interface UnleashMetricService {
+    void register(Set<String> strategies);
+    void count(String toggleName, boolean active);
+}

src/main/java/no/finn/unleash/metric/UnleashMetricServiceImpl.java

@@ -0,0 +1,55 @@
+package no.finn.unleash.metric;
+
+import no.finn.unleash.util.UnleashConfig;
+import no.finn.unleash.util.UnleashScheduledExecutor;
+
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Set;
+
+public class UnleashMetricServiceImpl implements UnleashMetricService {
+    private final LocalDateTime started;
+    private final UnleashConfig unleashConfig;
+    private final long metricsInterval;
+    private final UnleashMetricsSender unleashMetricsSender;
+
+    //mutable
+    private MetricsBucket currentMetricsBucket;
+
+    public UnleashMetricServiceImpl(UnleashConfig unleashConfig, UnleashScheduledExecutor executor) {
+        this(unleashConfig, new UnleashMetricsSender(unleashConfig), executor);
+    }
+
+    public UnleashMetricServiceImpl(UnleashConfig unleashConfig,
+                                    UnleashMetricsSender unleashMetricsSender,
+                                    UnleashScheduledExecutor executor) {
+        this.currentMetricsBucket = new MetricsBucket();
+        this.started = LocalDateTime.now(ZoneId.of("UTC"));
+        this.unleashConfig = unleashConfig;
+        this.metricsInterval = unleashConfig.getSendMetricsInterval();
+        this.unleashMetricsSender = unleashMetricsSender;
+
+        executor.setInterval(sendMetrics(), metricsInterval, metricsInterval);
+    }
+
+    @Override
+    public void register(Set<String> strategies) {
+        ClientRegistration registration = new ClientRegistration(unleashConfig, started, strategies);
+        unleashMetricsSender.registerClient(registration);
+    }
+
+    @Override
+    public void count(String toggleName, boolean active) {
+        currentMetricsBucket.registerCount(toggleName, active);
+    }
+
+    private Runnable sendMetrics() {
+        return () -> {
+            MetricsBucket metricsBucket = this.currentMetricsBucket;
+            this.currentMetricsBucket = new MetricsBucket();
+            metricsBucket.end();
+            ClientMetrics metrics = new ClientMetrics(unleashConfig, metricsBucket);
+            unleashMetricsSender.sendMetrics(metrics);
+        };
+    }
+}