A simple ping-pong service implementation that that integrates ringpop to forward requests between nodes.
Running the example
All commands are relative to this directory:
cd examples/ping-thrift
(optional, the files are already included) Generate the thrift code:
thrift-gen --generateThrift --outputDir gen-go --inputFile ping.thrift
Build the example binary:
go build
Start a custer of 5 nodes using tick-cluster:
tick-cluster.js -n 5 ping-thrift
Lookup the node my_key
key belongs to using tcurl:
$ tcurl ringpop -P hosts.json /admin/lookup '{"key": "my_key"}'
{"ok":true,"head":null,"body":{"dest":"127.0.0.1:3002"},"headers":{"as":"json"},"trace":"7a612e506428cec2"}
Call the PingPongService::Ping
endpoint (multiple times) and see the request being forwarded. Each request is sent to a random node in the cluster because of the -P hosts.json
argument--but is always handled by the node owning the key. This can be seen in the from
field of the response:
$ tcurl pingchannel -P hosts.json --thrift ./ping.thrift PingPongService::Ping '{"request": {"key": "my_key"}}'
{"ok":true,"head":{},"body":{"message":"Hello, world!","from_":"127.0.0.1:3002","pheader":""},"headers":{"as":"thrift"},"trace":"650cbf0656e215e2"}
Optionally, set the p
header. This value will be forwarded together with the request body to the node owning the key. Its value is returned in the response body in the pheader
field:
$ tcurl pingchannel -P hosts.json /ping '{"key": "my_key"}' --headers '{"p": "my_header"}'
{"ok":true,"head":{},"body":{"message":"Hello, world!","from_":"127.0.0.1:3002","pheader":"my_header"},"headers":{"as":"thrift"},"trace":"b5526f9625a88347"}