From 4b64dde196d34fa3568f80cc916ab0deece09e4d Mon Sep 17 00:00:00 2001 From: Mikhail Uvarov Date: Tue, 3 Sep 2024 18:01:13 +0200 Subject: [PATCH] Add three nodes example --- README.md | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/README.md b/README.md index eea7a883..3fc9b62f 100644 --- a/README.md +++ b/README.md @@ -80,3 +80,58 @@ Before making a new pull request run tests: ``` rebar3 all ``` + +# Three nodes example + +Create file with a list of cluster nodes. + +echo "node1@localhost\nnode2@localhost\nnode3@localhost" > /tmp/nodes.txt + +Open 3 shells in tmux. + +```bash +rebar3 shell --sname node1@localhost +rebar3 shell --sname node2@localhost +rebar3 shell --sname node3@localhost +``` + +On each node run: + +```erlang +{ok, Disco} = cets_discovery:start(#{disco_file => "/tmp/nodes.txt"}). +cets:start(test_table, #{}). +cets_discovery:add_table(Disco, test_table). +``` + +Check the list of nodes: + +```erlang +cets_discovery:info(Disco). +[#{memory => 201,size => 3,table => test_table, + nodes => [node1@localhost,node2@localhost,node3@localhost], + opts => #{}, + join_ref => #Ref<22882.3930565377.1965031426.177252>, + ack_pid => <0.1066.0>, + other_servers => [<22882.601.0>], + pause_monitors => [],node_down_history => []}] +``` + +Insert records on one of the nodes (read about keys considerations before): + +```erlang +cets:insert(test_table, {1, <<"test_info">>}). +cets:insert(test_table, {{cool_name, self()}, <<"use CETS as a process registry">>}). +``` + +Check records: + +```erlang +ets:tab2list(test_table). +[{1,<<"test_info">>}, + {{cool_name,<0.591.0>}, + <<"use CETS as a process registry">>}] +``` + +Use ets API to read records. + +Use supervision and `start_link` instead of `start` in the real world code.