4 ms·

I agree, and yet most microservice zealots seem to have a different opinion on this. e.g.: https://www.baeldung.com/cs/microservices-db-design https://www.bael

by Pamar 4y ago

I agree, and yet most microservice zealots seem to have a different opinion on this. e.g.: https://www.baeldung.com/cs/microservices-db-design https://www.baeldung.com/cs/microservices-db-design "2.1. Fundamentals By definition, microservices should be loosely coupled, scalable, and independent in terms of development and deployment. Therefore, the database per service is a preferred approach as it perfectly meets those requirements. Let’s see how it looks:" Please understand that I have worked only on monoliths and will probably retire while still working on monoliths. This kind of absurd positions only come up when someone comes to my office with some grand plan to convert the application I work on to something "more microservice oriented".

ReflectedImage 4y ago
Whilst I don't know much about cruises. Let me make up an example for you. Let's suppose we are Acme Cruise Lines running a Cruiseliner: Microservice - National Coastguard Ship Arrival System Feed Handler Database - Logs incoming messages on the feed Microservice - Asian and Australian Joint Ship Monitoring System Database - Logs incoming messages on the feed Microservice - Cruiser Arrival and Departure Times Database - Cruiser Arrival and Departures Times in a Standard Format Microservice - Customer Bookings and Payments Database - Customer Bookings and Payments Microservice - Fuel Management System Database - Ship Fuel Levels & Costs of fuel at Various Ports. It's that high level of split up. (AWS Lambdas aren't quite the same thing as microservices.)
- Pamar 4y ago
  You are absolutely right: you do not know much about cruises. The things you listed are ... 4-5 different applications, mostly running directly on the ship(s) and what is conspicuously missing are the parts that are managed shoreside, like: Itinerary planning (your product is one or more cruises: therefore you need to preplan the itineraries, which ships to use, when you will enter each port and when you will leave it, and so on... try to imagine this like a mix between hotel management and flight company management) Inventory management (i.e. Reservation). You mention "bookings" like a microservice. This could work for ferry line, where you are basically selling a ticket for a single trip, most of the time with no personal accommodation (except maybe for the car). A Cruise booking usually comes with a ton of ancillary services (e.g. I live in Berlin and I want to take a cruise in the Caribbeans... therefore I need a flight to get there and back. This could be provided by a charter flight or a normal airline ... in either cases the ticket will be part of the booking itself) - take in account that cruise customers are mostly middle-aged or older and relatively affluent, therefore the last thing they would like to do is to create their own itinerary by booking services on 4-5 different websites. (But I suppose it is better to stop there, we are really OT now)
  - ReflectedImage 4y ago
    "4-5 different websites" No, no, no. Those are internal APIs. You still only present one website to the end user.
    - Pamar 4y ago
      Sorry, you misunderstood. When you book a cruise, your expectation is to get everything (including hotel stays before or after the cruise, along with flights to and from it) as a single package provided by the cruise vendor (or a travel agency). So the "reservation system" must take care of all of that. When I said "4-5 different websites" I was trying to explain the point that a 60 yo high-income guy is usually not interested in getting the cruise itself on Carnival.com, then go look for excursions on CarribeansExcursion.net and to book flights on Lufthansa.de or AirFrance.fr. It was a remark on the way the Cruise business works, and why it is so, not about architecture. (But, once again, I really believe that we are way off topic... personally I do not really feel like creating a "Ask HN: are microservices a good choice for the cruise industry?" but if someone feels like submitting one I will try to contribute).

by Pamar 4y ago

ReflectedImage 4y ago

Whilst I don't know much about cruises. Let me make up an example for you. Let's suppose we are Acme Cruise Lines running a Cruiseliner: Microservice - National Coastguard Ship Arrival System Feed Handler Database - Logs incoming messages on the feed Microservice - Asian and Australian Joint Ship Monitoring System Database - Logs incoming messages on the feed Microservice - Cruiser Arrival and Departure Times Database - Cruiser Arrival and Departures Times in a Standard Format Microservice - Customer Bookings and Payments Database - Customer Bookings and Payments Microservice - Fuel Management System Database - Ship Fuel Levels & Costs of fuel at Various Ports. It's that high level of split up. (AWS Lambdas aren't quite the same thing as microservices.)

Pamar 4y ago
You are absolutely right: you do not know much about cruises. The things you listed are ... 4-5 different applications, mostly running directly on the ship(s) and what is conspicuously missing are the parts that are managed shoreside, like: Itinerary planning (your product is one or more cruises: therefore you need to preplan the itineraries, which ships to use, when you will enter each port and when you will leave it, and so on... try to imagine this like a mix between hotel management and flight company management) Inventory management (i.e. Reservation). You mention "bookings" like a microservice. This could work for ferry line, where you are basically selling a ticket for a single trip, most of the time with no personal accommodation (except maybe for the car). A Cruise booking usually comes with a ton of ancillary services (e.g. I live in Berlin and I want to take a cruise in the Caribbeans... therefore I need a flight to get there and back. This could be provided by a charter flight or a normal airline ... in either cases the ticket will be part of the booking itself) - take in account that cruise customers are mostly middle-aged or older and relatively affluent, therefore the last thing they would like to do is to create their own itinerary by booking services on 4-5 different websites. (But I suppose it is better to stop there, we are really OT now)
- ReflectedImage 4y ago
  "4-5 different websites" No, no, no. Those are internal APIs. You still only present one website to the end user.
  - Pamar 4y ago
    Sorry, you misunderstood. When you book a cruise, your expectation is to get everything (including hotel stays before or after the cruise, along with flights to and from it) as a single package provided by the cruise vendor (or a travel agency). So the "reservation system" must take care of all of that. When I said "4-5 different websites" I was trying to explain the point that a 60 yo high-income guy is usually not interested in getting the cruise itself on Carnival.com, then go look for excursions on CarribeansExcursion.net and to book flights on Lufthansa.de or AirFrance.fr. It was a remark on the way the Cruise business works, and why it is so, not about architecture. (But, once again, I really believe that we are way off topic... personally I do not really feel like creating a "Ask HN: are microservices a good choice for the cruise industry?" but if someone feels like submitting one I will try to contribute).