Bridge is an API bridge registry designed to enable communication between HTTP and Websocket (WS) endpoints.
If available in Hex, the package can be installed
by adding bridge to your list of dependencies in mix.exs:
def deps do
[
{:bridge, "~> 0.1.0"}
]
endDocumentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/bridge.
$ iex -S mix
This will start the the application supervision tree defined in "lib/bridge/application.ex" The bridge server is a supervised process.
Start be creating a supervised bridge server. The uuid of bridge is used for interacting with it.
iex> {:ok, pid, uuid} = Bridge.Supervisor.create_bridge()
{:ok, #PID<0.136.0>}
You can then add/get messages from the Bridge.Server
iex> alias Bridge.Message
:ok
iex> msg = Message.create("api/", uuid, %{data: "stuff"})
:ok
iex> Bridge.add_message(uuid, msg)
:ok
iex> Bridge.get_message(uuid)
{:ok,
%Bridge.Message{endpoint: "api/", payload: %{data: "stuff"},
uuid: "wiLsm+Ggs1CrMnHjB"}}
If the supervised process crashes the supervisor will restart it
iex> Registry.lookup(:api_bridge_registry, uuid) |> List.first() |> elem(0) |> Process.exit(:kill)
true
iex> Bridge.get_message(uuid)
{:error, "Process uuid no longer exists"}
iex> Bridge.add_message(uuid, msg)
:ok
iex> Bridge.get_message(uuid)
{:ok,
%Bridge.Message{endpoint: "api/", payload: %{data: "stuff"},
uuid: "wiLsm+Ggs1CrMnHjB"}}
We see above that the process is killed automatically restarted, while it does not retain messages, new messages can be added and then retrieved.
This next example shows how you can create a bridge and then start a task to listen for a response over that bridge. While here we are simply adding the message after a second this could be happing in any other process as long as it has access to the Bridge module.
alias Bridge.Message
response_timeout = 20000
{:ok, pid, uuid} = Bridge.Supervisor.create_bridge()
msg = Message.create("api/", uuid, %{data: "more stuff"})
task = Bridge.response_async(uuid, response_timeout)
:timer.sleep(1000)
Bridge.add_message(uuid, msg)
results = Task.await(task)
IO.puts "task result = #{inspect results}"
task = Task.async(Bridge, :response, [uuid, response_timeout])