Kane
Kane. Citizen Kane. Charles Foster Kane, to be exact, Publisher extraordinaire. Rosebud.
Kane is for publishing and subscribing to topics using Google Cloud Pub/Sub.
Installation
- Add Kane to your list of dependencies in
mix.exs:
def deps do
[{:kane, "~> 0.9.0"}]
end- Configure Goth (Kane's underlying token storage and retrieval library) with your Google JSON credentials:
config :goth,
json: "path/to/google/json/creds.json" |> File.read!- Ensure Kane is started before your application:
def application do
[applications: [:kane]]
endUsage
Pull, process and acknowledge messages via a pre-existing subscription:
subscription = %Kane.Subscription{
name: "my-sub",
topic: %Kane.Topic{
name: "my-topic"
}
}
{:ok, messages} = Kane.Subscription.pull(subscription)
Enum.each messages, fn(mess)->
process_message(mess)
end
# acknowledge message receipt in bulk
Kane.Subscription.ack(subscription, messages)Send message via pre-existing subscription:
topic = %Kane.Topic{name: "my-topic"}
message = %Kane.Message{data: %{"hello": "world"}, attributes: %{"random" => "attr"}}
result = Kane.Message.publish(message, topic)
case result do
{:ok, _return} -> IO.puts("It worked!")
{:error, _reason} -> IO.puts("Should we try again?")
endHints:
- Attributes have to be Strings (https://cloud.google.com/pubsub/docs/reference/rest/v1/PubsubMessage)
- We base64-encode the message by default (only mandatory when using json - https://cloud.google.com/pubsub/publisher)
For more details, see the documentation.