code: @GET
      @Path("/{guid}")
      @Consumes(Servlets.JSON_MEDIA_TYPE)
      @Produces(Servlets.JSON_MEDIA_TYPE)
      public AtlasLineageInfo getLineageGraph(@PathParam("guid") String guid,
                                              @QueryParam("direction") @DefaultValue(DEFAULT_DIRECTION)  LineageDirection direction,
                                              @QueryParam("depth") @DefaultValue(DEFAULT_DEPTH) int depth) throws AtlasBaseException {
          AtlasPerfTracer perf = null;
  
          try {
              if (AtlasPerfTracer.isPerfTraceEnabled(PERF_LOG)) {
                  perf = AtlasPerfTracer.getPerfTracer(PERF_LOG, "LineageREST.getLineageGraph(" + guid + "," + direction +
                                                                 "," + depth + ")");
              }
  
              return atlasLineageService.getAtlasLineageInfo(guid, direction, depth);
          } finally {
              AtlasPerfTracer.log(perf);
          }
      }
docs: Returns lineage info about entity.
  @param guid - unique entity id
  @param direction - input, output or both
  @param depth - number of hops for lineage
  @return AtlasLineageInfo
  @throws AtlasBaseException
  @HTTP 200 If Lineage exists for the given entity
  @HTTP 400 Bad query parameters
  @HTTP 404 If no lineage is found for the given entity