What was found
FLIGHT 7816 - YYA-IAD - DURING TAKEOFF, RECEIVED "HYD 1 LOW QTY". DURING CLIMB, RECEIVED "E1 HYD PUMP FAIL". RAN QRH AND SHUT OFF ELECTRIC HYDRAULIC PUMP 1, GEAR DOORS OPENED DUE TO LACK OF PRESSURE. DECLARED AN EMERGENCY DUE TO NO FLUID IN THE ENGINE DRIVEN PUMP. TRIED TO NORMALLY EXTEND THE GEAR, BUT IT DID NOT LOWER. FOLLOWED QRH FOR ABNORMAL EXTENSION OF GEAR, DIVERTED TO BUF WITH NO INCIDENT. "E1 HYD PUMP FAIL" CLEARED FROM EICAS. MAINTENANCE REMOVED AND REPLACED THE ENGINE DRIVEN PUMP.