config

Overview ¶

Config provides decoupling between various configuration sources (etcd, files,...) and the pieces that actually care about them (loadbalancer, proxy). Config takes 1 or more configuration sources and allows for incremental (add/remove) and full replace (set) changes from each of the sources, then creates a union of the configuration and provides a unified view for both service handlers as well as endpoint handlers. There is no attempt to resolve conflicts of any sort. Basic idea is that each configuration source gets a channel from the Config service and pushes updates to it via that channel. Config then keeps track of incremental & replace changes and distributes them to listeners as appropriate.

Watches etcd and gets the full configuration on preset intervals. Expects the list of exposed services to live under: registry/services which in etcd is exposed like so: http://<etcd server>/v2/keys/registry/services

The port that proxy needs to listen in for each service is a value in: registry/services/<service>

The endpoints for each of the services found is a json string representing that service at: /registry/services/<service>/endpoint and the format is: '[ { "machine": <host>, "name": <name", "port": <port> },

  { "machine": <host2>, "name": <name2", "port": <port2> }
]',

Reads the configuration from the file. Example file for two services [nodejs & mysql] {"Services": [

{
   "Name":"nodejs",
   "Port":10000,
   "Endpoints":["10.240.180.168:8000", "10.240.254.199:8000", "10.240.62.150:8000"]
},
{
   "Name":"mysql",
   "Port":10001,
   "Endpoints":["10.240.180.168:9000", "10.240.254.199:9000", "10.240.62.150:9000"]
}

] }