Add breadcrumb support

I've tried to keep the API as high-level as possible, and not expose too
much to the user.

Fixes #70

sentry-android/src/main/java/com/joshdholtz/sentry/Sentry.java

@@ -22,6 +22,7 @@
 import org.apache.http.conn.scheme.SchemeRegistry;
 import org.apache.http.conn.ssl.SSLSocketFactory;
 import org.apache.http.entity.StringEntity;
+import org.apache.http.impl.EnglishReasonPhraseCatalog;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.params.HttpConnectionParams;
 import org.apache.http.params.HttpParams;
@@ -60,6 +61,7 @@
 import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -82,6 +84,7 @@ public class Sentry {
     private final static String VERSION = "0.2.0";
     private final static String sentryVersion = "7";
     private static final int MAX_QUEUE_LENGTH = 50;
+    private static final int MAX_BREADCRUMBS = 10;
 
     public static boolean debug = false;
 
@@ -94,6 +97,9 @@ public class Sentry {
     private JSONObject contexts = new JSONObject();
     private Executor executor;
 
+
+    private LinkedList<Breadcrumb> breadcrumbs = new LinkedList<>();
+
     public enum SentryEventLevel {
 
         FATAL("fatal"),
@@ -148,6 +154,8 @@ public static void init(Context context, String dsn, boolean setupUncaughtExcept
 
         if (setupUncaughtExceptionHandler) {
             Sentry.getInstance().setupUncaughtExceptionHandler();
+
+
         }
     }
 
@@ -304,6 +312,7 @@ public static void captureEvent(SentryEventBuilder builder) {
         if (Sentry.getInstance().packageInfo != null) {
             builder.setRelease(Integer.toString(Sentry.getInstance().packageInfo.versionCode));
         }
+        builder.event.put("breadcrumbs", Sentry.getInstance().currentBreadcrumbs());
         if (Sentry.getInstance().captureListener != null) {
 
             builder = Sentry.getInstance().captureListener.beforeCapture(builder);
@@ -610,6 +619,104 @@ public interface SentryEventCaptureListener {
 
     }
 
+
+
+    public final static class Breadcrumb {
+
+        enum Type {
+
+            Default("default"),
+            HTTP("http"),
+            Navigation("navigation");
+
+            private final String value;
+
+            Type(String value) {
+                this.value = value;
+            }
+        }
+
+        public final long timestamp;
+        public final Type type;
+        public final String message;
+        public final String category;
+        public final SentryEventLevel level;
+        public final Map<String, String> data = new HashMap<>();
+
+        public Breadcrumb(long timestamp, Type type, String message, String category, SentryEventLevel level) {
+            this.timestamp = timestamp;
+            this.type = type;
+            this.message = message;
+            this.category = category;
+            this.level = level;
+        }
+    }
+
+    private void pushBreadcrum(Breadcrumb b) {
+        while (breadcrumbs.size() >= MAX_BREADCRUMBS) {
+            breadcrumbs.removeFirst();
+        }
+        breadcrumbs.add(b);
+    }
+
+    public static void addNavigationBreadcrumb(String category, String from, String to) {
+        final Breadcrumb b = new Breadcrumb(
+            System.currentTimeMillis()/1000,
+            Breadcrumb.Type.Navigation,
+            "",
+            category,
+            SentryEventLevel.INFO);
+
+        b.data.put("from", from);
+        b.data.put("to", to);
+        getInstance().pushBreadcrum(b);
+    }
+
+    public static void addHttpBreadcrumb(String url, String method, int statusCode) {
+        final String reason = EnglishReasonPhraseCatalog.INSTANCE.getReason(statusCode, Locale.US);
+        final Breadcrumb b = new Breadcrumb(
+            System.currentTimeMillis()/1000,
+            Breadcrumb.Type.HTTP,
+            "",
+            String.format("http.%s", method.toLowerCase()),
+            SentryEventLevel.INFO);
+
+        b.data.put("url", url);
+        b.data.put("method", method);
+        b.data.put("status_code", Integer.toString(statusCode));
+        b.data.put("reason", reason);
+        getInstance().pushBreadcrum(b);
+    }
+
+    public static void addBreadcrumb(String category, String message) {
+        getInstance().pushBreadcrum(new Breadcrumb(
+            System.currentTimeMillis()/1000,
+            Breadcrumb.Type.Default,
+            message,
+            category,
+            SentryEventLevel.INFO));
+    }
+
+    private JSONArray currentBreadcrumbs() {
+        final JSONArray crumbs = new JSONArray();
+        for (Breadcrumb breadcrumb  : breadcrumbs) {
+            final JSONObject json = new JSONObject();
+
+            try {
+                json.put("timestamp", breadcrumb.timestamp);
+                json.put("type", breadcrumb.type.value);
+                json.put("message", breadcrumb.message);
+                json.put("category", breadcrumb.category);
+                json.put("level", breadcrumb.level.value);
+                json.put("data", new JSONObject(breadcrumb.data));
+            } catch (JSONException jse) {
+                Log.e(TAG, "Error serializing breadcrumbs", jse);
+            }
+            crumbs.put(json);
+        }
+        return crumbs;
+    }
+
     public static class SentryEventRequest implements Serializable {
         private final String requestData;
         private final UUID uuid;