brod_oauth is a plugin for brod which adds SASL/OAUTHBEARER auth support.
Add brod_oauth to your deps in rebar.config or mix.exs :
{deps, [{brod_oauth, "0.1.0"}]}.{:brod_oauth, "~> 0.1.0"}NOTE : brod_oauth requires kafka_protocol >= 4.1.8.
The only required configuration for brod is a sasl callback tuple with specific configuration
for brod_oauth enclosed in a map. See brod authentication
support
for more general information on authentication support in brod.
Required keys :
token_callback: An arity 1 callback function. Said function is given a map containing connection properties and expected to return a map containing the keytoken, pointing to a valid JWT retrieved from an oauth provider. The current properties passed to the callback are as follows :client_id: The client id of the brod client instance.host: Hostname for the current connection requiring auth.timeout: The timeout value associated with connection (i.e.,connect_timeout).
Optional keys :
authz_id: A utf-8 binary authz id value.extensions: A map of key value pairs, most commonly a logical cluster id and identity pool id.
Note : While the the examples below demonstrate providing extensions in configuration, it is not a
required parameter, and not all setups require extensions to be provided. Such is the case with
authz_id as well.
-module(example).
-export([start_client/0, fetch_token/1]).
fetch_token(#{client_id := _, host := _, timeout := _) ->
BodyParams = [
{"grant_type", "grant_type"},
{"client_secret", "client_secret"},
{"client_id", "client_id"},
{"scope", "scope"}
],
Body = uri_string:compose_query(BodyParams1),
Res = httpc:request(
post,
{"https://my.oauth.provider", [], "application/x-www-form-urlencoded", Body},
[],
[{body_format, binary}]
),
case Res of
{ok, {{"HTTP/1.1", 200, "OK"}, _headers, Json}} ->
#{<<"access_token">> := Token} = json:decode(Json),
{ok, #{
token => Token
}};
_Err ->
{error, failed_to_obtain_jwt}
end.
start_client() ->
BootstrapEndpoints = [{"my.kafka.broker.host", 9092}],
Extensions = #{
<<"logicalCluster">> => <<"lkc-1234">>,
<<"identityPoolId">> => <<"pool-4321">>},
BrodOauthConfig = #{token_callback => fun example:fetch_token/1, extensions => Extensions},
BrodConfig = [{connect_timeout, 60000},
{sasl, {callback, brod_oauth, BrodOauthConfig}}],
ok = brod:start_client(BootstrapEndpoints, my_client, BrodConfig).defmodule Example do
def oauth_params(%{client_id: _, host: _, timeout: _) do
body_params = %{
"grant_type" => "grant_type",
"client_secret" => "client_secret",
"client_id" => "client_id",
"scope" => "scope"
}
body = URI.encode_query(body_params1)
res =
:httpc.request(
:post,
{to_charlist(oauth_config.url), [], ~c"application/x-www-form-urlencoded",
to_charlist(body)},
[],
[{:body_format, :binary}]
)
case res do
{:ok, {{~c"HTTP/1.1", 200, ~c"OK"}, _headers, json}} ->
%{"access_token" => token} = :json.decode(json)
{:ok,
%{
token: token,
extensions: extensions
}}
_ ->
{:error, :failed_to_obtain_jwt}
end
end
def start_client() do
bootstrap_endpoints = [{"my.kafka.broker.host", 9092}]
extensions = %{"logicalCluster" => "lkc-1234", "identityPoolId" => "pool-4321"}
brod_oauth_config = %{token_callback: &Example:fetch_token/1, extensions: extensions}
brod_config = [connect_timeout: 60000, sasl: {:callback, :brod_oauth, brod_oauth_config}}]
:ok = :brod.start_client(bootstrap_endpoints, :my_client, brod_config)
end
See the examples for more detail.