Finer-grained repository access permissions (issue 36)

Implemented discrete repository access permissions to replace the
really primitive course-grained permissions used to this point.  This
implementation allows for finer-grained access control, but still
falls short of integrated, branch-based permissions sought by some.

Access permissions follow the conventions established by Gitosis and
Gitolite so they should feel immediately comfortable to experienced
users.  This permissions infrastructure is complete and works exactly as
expected.  Unfortunately, there is no ui in this commit to change
permissions, that will be forthcoming.  In the meantime, Gitblit
hot-reloads users.conf so the permissions can be manipulated at runtime
with a text editor.

The following per-repository permissions are now supported:
- V (view in web ui, RSS feeds, download zip)
- R (clone)
- RW (clone and push)
- RWC (clone and push with ref creation)
- RWD (clone and push with ref creation, deletion)
- RW+ (clone and push with ref creation, deletion, rewind)

And a users.conf entry looks something like this:

	[user "hannibal"]
		password = bossman
		repository = RWD:topsecret.git

1 files changed, 20 insertions, 0 deletions

diff --git a/src/com/gitblit/utils/JsonUtils.java b/src/com/gitblit/utils/JsonUtils.java
index bc9a1e00..24f4ecb8 100644
--- a/src/com/gitblit/utils/JsonUtils.java
+++ b/src/com/gitblit/utils/JsonUtils.java
@@ -32,6 +32,7 @@ import java.util.Locale;
 import java.util.Map;

 import java.util.TimeZone;

 

+import com.gitblit.Constants.AccessPermission;

 import com.gitblit.GitBlitException.ForbiddenException;

 import com.gitblit.GitBlitException.NotAllowedException;

 import com.gitblit.GitBlitException.UnauthorizedException;

@@ -266,6 +267,7 @@ public class JsonUtils {
 	public static Gson gson(ExclusionStrategy... strategies) {

 		GsonBuilder builder = new GsonBuilder();

 		builder.registerTypeAdapter(Date.class, new GmtDateTypeAdapter());

+		builder.registerTypeAdapter(AccessPermission.class, new AccessPermissionTypeAdapter());

 		builder.setPrettyPrinting();

 		if (!ArrayUtils.isEmpty(strategies)) {

 			builder.setExclusionStrategies(strategies);

@@ -303,6 +305,24 @@ public class JsonUtils {
 			}

 		}

 	}

+	

+	private static class AccessPermissionTypeAdapter implements JsonSerializer<AccessPermission>, JsonDeserializer<AccessPermission> {

+

+		private AccessPermissionTypeAdapter() {

+		}

+

+		@Override

+		public synchronized JsonElement serialize(AccessPermission permission, Type type,

+				JsonSerializationContext jsonSerializationContext) {

+			return new JsonPrimitive(permission.code);

+		}

+

+		@Override

+		public synchronized AccessPermission deserialize(JsonElement jsonElement, Type type,

+				JsonDeserializationContext jsonDeserializationContext) {

+			return AccessPermission.fromCode(jsonElement.getAsString());					

+		}

+	}

 

 	public static class ExcludeField implements ExclusionStrategy {