Naming system : helpers function for server referenced by name only

[PierreBizouard]

[Paul Eipper]

Can you describe the architecture for this system and features?

I usually avoid RPC that have naming servers because of the extra infrastructure, that can usually be replaced by a common DNS system which is already deployed.

[PierreBizouard]

PIZCO NAMING SYSTEM

Objectives

Providing a distributed naming system, similar to bonjour/avahi but for
pizco objects only.

Rough Architecture

The naming server consist in 3 components:

• A beacon that does UDP broadcast/receive on wildcard address on port
  PZC_BEACON_PORT(default:9999)
• A service watchdog system that ping registered services/server on
  localhost:service_port at 1second interval
• A Naming service (which is a pizco server) that takes care of
  • the new hosts (via the beacon and hosts that disconnects)
    • by connecting their Naming Service (pizco server) and their
      registered services.
  • the new services (via a client interface (for registering) and via
    the service watchdog which looks for
    services that disconnects)
  • No polling is required due to the nature of signal and slots.

Known issues

• No helpers function to register *:0 services only by name / add
  hostname.service automatic naming.
  / add hostname.service-x for service allready existing.
• Knowaday beacon and watchdog are threaded that could be moved to *:0
  pizco objects for further performance.
• udp_broadcast_relay must be use for complex network, require rebuilding
  on some routers.

Thank you for the question :) it allows me to write some doc and
rethink/sync about it! ;)

2014-08-24 18:11 GMT+02:00 Paul Eipper [e-mail]:

Can you describe the architecture for this system and features?

I usually avoid RPC that have naming servers because of the extra
infrastructure, that can usually be replaced by a common DNS system which
is usually already deployed.

—
Reply to this email directly or view it on GitHub
#19 (comment).

[PierreBizouard]

Another issue is the question of who starts it's naming server on the
system (on windows) because of the lack of fork, the naming system will be
destroyed when the first app (having start the server) will close. The
naming service proxy will then hang on clients if launched. And naming
service of the host will disappear, leaving services unnamed.

Two options :

• Start the naming system independently of pizco using programs.

• Another option is to start the naming service in another executable (not
  as a child process of python) that remains loaded (which will be addressed
  by pizco utils)

• [LONG way ahead] Another option is to distribute the execution of the
  naming system between main processes, maybe a signal sent to other
  processes using the naming service can be used to respawn the server. or
  the proxy of the naming system, should be ping/polling the naming server.
  And restart as a new service if exiting, with the local service list.
  + When the naming sytem is started as a Proxy Only
  + create a pizco object that can receive signal from
  the naming server's process death and relaunch the server)
  + create a pizco object that polls something (process,
  beacon port and relaunch the server).

     + keep a list of numbered proxies with rank (second started will
  

  be responsible for restarting the proxy if it finds the beacon missing / or
  receive the signal from the main thread (with the local proxies list)).
  lower the rank of all other proxies.

     + if the second proxy disconnects/or starts the server, it
  

  registers the restart to the third etc.

     + restart the proxies if the previous proxy stops. will be
  

  complicated.

2014-08-25 14:16 GMT+02:00 Pierre Bizouard [e-mail]:

PIZCO NAMING SYSTEM

Objectives

Providing a distributed naming system, similar to bonjour/avahi but for
pizco objects only.

Rough Architecture

The naming server consist in 3 components:

• A beacon that does UDP broadcast/receive on wildcard address on port
  PZC_BEACON_PORT(default:9999)
• A service watchdog system that ping registered services/server on
  localhost:service_port at 1second interval
• A Naming service (which is a pizco server) that takes care of
  • the new hosts (via the beacon and hosts that disconnects)
    • by connecting their Naming Service (pizco server) and their
      registered services.
  • the new services (via a client interface (for registering) and via
    the service watchdog which looks for
    services that disconnects)
  • No polling is required due to the nature of signal and slots.

Known issues

• No helpers function to register *:0 services only by name / add
  hostname.service automatic naming.
  / add hostname.service-x for service allready existing.
• Knowaday beacon and watchdog are threaded that could be moved to *:0
  pizco objects for further performance.
• udp_broadcast_relay must be use for complex network, require rebuilding
  on some routers.

Thank you for the question :) it allows me to write some doc and
rethink/sync about it! ;)

2014-08-24 18:11 GMT+02:00 Paul Eipper [e-mail]:

Can you describe the architecture for this system and features?

I usually avoid RPC that have naming servers because of the extra
infrastructure, that can usually be replaced by a common DNS system which
is usually already deployed.

—
Reply to this email directly or view it on GitHub
#19 (comment).