Support JSON and GCL log formats

Co-authored-by: Ariel Simulevski <Azer0s@users.noreply.github.com>

CHANGELOG.md

@@ -18,6 +18,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added detailed features summary on the website with architecture diagrams. [#284](https://github.com/Accenture/reactive-interaction-gateway/issues/284)
 - Added [documentation section](https://accenture.github.io/reactive-interaction-gateway/docs/jwt-blacklisting.html) for the JWT Blacklist feature. [#156](https://github.com/Accenture/reactive-interaction-gateway/issues/156)
 - Added longpolling examples to the `/examples` folder [#235](https://github.com/Accenture/reactive-interaction-gateway/issues/235)
+- Support JSON and Google Cloud Logger (GCL) log formats. Set the new environment variable `LOG_FMT` to `JSON` or `GCL` to see this in action.
+  [#298](https://github.com/Accenture/reactive-interaction-gateway/pull/298)
 
 ### Changed
 

config/config.exs

@@ -81,8 +81,13 @@ config :logger, :console,
   format: "\n$time [$level] $levelpad$message\n$metadata\n",
   metadata: metadata |> Enum.uniq()
 
+# The logger is configured on Application startup.
+config :logger,
+  backends: []
+
 config :rig, Rig.Application,
-  log_level: {:system, :atom, "LOG_LEVEL", :debug},
+  log_level: {:system, "LOG_LEVEL", "debug"},
+  log_fmt: {:system, "LOG_FMT", "erlang"},
   schema_registry_host: {:system, "KAFKA_SCHEMA_REGISTRY_HOST", nil}
 
 # --------------------------------------

config/prod.exs

@@ -1,7 +1,7 @@
 use Mix.Config
 
 # Do not print debug messages in production
-config :rig, Rig.Application, log_level: {:system, :atom, "LOG_LEVEL", :warn}
+config :rig, Rig.Application, log_level: {:system, "LOG_LEVEL", "warn"}
 
 # --------------------------------------
 # Peerage

config/test.exs

@@ -5,7 +5,7 @@ config :rig, Rig.Kafka, enabled?: true
 config :rig, Rig.KafkaTest, topic: "rig"
 
 # Print only warnings and errors during test
-config :rig, Rig.Application, log_level: {:system, :atom, "LOG_LEVEL", :warn}
+config :rig, Rig.Application, log_level: {:system, "LOG_LEVEL", "warn"}
 
 jwt_secret_key = "mysecret"
 jwt_alg = "HS256"

docs/rig-ops-guide.md

@@ -50,7 +50,8 @@ Variable            
 `KINESIS_LOG_LEVEL` | The log level for the (Java) Kinesis-client subsystem. Allowed values: OFF, SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST, ALL. | "INFO"
 `KINESIS_OTP_JAR` | Path to the `OtpErlang.jar` file that contains the `JInterface` implementation. If left empty, RIG picks the file from its Erlang environment (Erlang must be compiled with Java support enabled). | nil
 `KINESIS_STREAM` | The name of the Kinesis stream to consume. | "RIG-outbound"
-`LOG_LEVEL` | Controls logging level for RIG, available values are: "debug", "info", "warn", "error". Production is using "warn" level. | :warn
+`LOG_LEVEL` | Log level. One of: `debug`, `info`, `warn`, `error`. | "warn"
+`LOG_FMT` | Log format. May be set to `json` or `gcl` (Google Cloud Logger LogEntry format). | "erlang"
 `NATS_SERVERS` | List of [NATS](https://nats.io) servers RIG should connect to, delimited by comma (e.g., `localhost:4222,example.com:4222`). | []
 `NATS_SOURCE_TOPICS` | List of NATS topics to subscribe to, delimited by comma. | ["rig"]
 `NATSTOFILTER_QUEUE_GROUP` | NATS [queue group](https://docs.nats.io/developing-with-nats/receiving/queues) used for forwarding events according to subscriptions over SSE and WS connections. Make sure to use the same value on all RIG instances that belong to the same cluster. The default should be fine. | "rig-nats-to-filter"
@@ -64,7 +65,7 @@ Variable            
 `PROXY_KAFKA_RESPONSE_TIMEOUT` | In case an endpoint has `target` set to `http` and `response_from` set to `kafka`, this is the maximum delay between an HTTP request and the corresponding Kafka response message. | 5000
 `PROXY_KINESIS_RESPONSE_TIMEOUT` | In case an endpoint has `target` set to `http` and `response_from` set to `kinesis`, this is the maximum delay between an HTTP request and the corresponding Kinesis response message. | 5000
 `PROXY_KINESIS_REQUEST_REGION` | AWS region for Kinesis stream publishing events from proxy. | "eu-west-1"
-`PROXY_NATS_RESPONSE_TIMEOUT` | If `response_from` is set to `nats`, this defines how long RIG waits for the response. | 60_000
+`PROXY_NATS_RESPONSE_TIMEOUT` | If `response_from` is set to `nats`, this defines how long RIG waits for the response. | 60000
 `REQUEST_LOG` | Type of loggers to use to log requests processed by API Proxy, delimited by comma. | []
 `SUBMISSION_CHECK` | Select if and how submitting/publishing events should be denied. Can be either `no_check` (submissions are always allowed), `jwt_validation` (submissions are allowed if at least one authorization token is valid - using JWT_SECRET_KEY - and not blacklisted), or an URL that points to an external service that decides whether to allow or deny the submissions. Such an external service is expected to accept POST requests. The CloudEvent is passed as a JSON map in the body. The original request's `Authorization` headers are reused for this request. The submission is allowed if the service returns 2xx and denied otherwise; return either 401 or 403 to reject a submission request. | "NO_CHECK"
 `SUBSCRIPTION_CHECK` | Select if and how creating subscriptions should be denied. Can be either `no_check` (subscriptions are always allowed), `jwt_validation` (subscription are allowed if at least one authorization token is valid - using JWT_SECRET_KEY - and not blacklisted), or an URL that points to an external service that decides whether to allow or deny the subscription. Such an external service is expected to accept POST requests. The subscription parameters are passed in the body. The original request's `Authorization` headers are reused for this request. The subscription is allowed if the service returns 2xx and denied otherwise; return either 401 or 403 to reject a subscription request. | "NO_CHECK"

lib/rig/application.ex

@@ -2,17 +2,18 @@ defmodule Rig.Application do
   @moduledoc false
 
   use Application
-  use Rig.Config, [:log_level, :schema_registry_host]
+  use Rig.Config, [:log_level, :log_fmt, :schema_registry_host]
 
   alias RIG.Discovery
   alias RIG.Tracing
   alias RigOutboundGateway.Kinesis
 
+  alias LoggerJSON.Formatters.BasicLogger
+
   def start(_type, _args) do
     alias Supervisor.Spec
 
-    # Override application logging with environment variable
-    Logger.configure([{:level, config().log_level}])
+    setup_logger()
 
     Tracing.start()
     Discovery.start()
@@ -55,6 +56,41 @@ defmodule Rig.Application do
     Supervisor.start_link(children, opts)
   end
 
+  defp setup_logger do
+    conf = config() |> IO.inspect(label: "config()")
+    level = conf.log_level |> String.downcase() |> String.to_atom()
+    format = conf.log_fmt |> String.downcase()
+
+    # Override application logging with environment variable
+    Logger.configure([{:level, level}])
+    setup_logger_backend(format)
+  end
+
+  defp setup_logger_backend(format)
+
+  defp setup_logger_backend("json") do
+    Logger.add_backend(LoggerJSON)
+
+    Logger.configure_backend(LoggerJSON,
+      formatter: LoggerJSON.Formatters.BasicLogger,
+      metadata: :all
+    )
+  end
+
+  # Google Cloud Logger format
+  defp setup_logger_backend("gcl") do
+    Logger.add_backend(LoggerJSON)
+
+    Logger.configure_backend(LoggerJSON,
+      formatter: LoggerJSON.Formatters.GoogleCloudLogger,
+      metadata: :all
+    )
+  end
+
+  defp setup_logger_backend("erlang") do
+    Logger.add_backend(:console)
+  end
+
   @doc """
   This function is called by an application after a code replacement, if the configuration parameters have changed.
 

mix.exs

@@ -61,7 +61,6 @@ defmodule RIG.MixProject do
     [
       mod: {Rig.Application, []},
       extra_applications: [
-        :logger,
         :runtime_tools,
         :prometheus_ex,
         :prometheus_plugs
@@ -179,7 +178,9 @@ defmodule RIG.MixProject do
       {:opencensus_jaeger, "~> 0.0.1"},
       {:opencensus_zipkin, "~> 0.3"},
       # NATS client:
-      {:gnat, "~> 1.0"}
+      {:gnat, "~> 1.0"},
+      # JSON Log backend
+      {:logger_json, "~> 4.0"}
     ]
   end
 

mix.lock

@@ -44,6 +44,7 @@
   "jsone": {:hex, :jsone, "1.4.6", "644d6d57befb22c8e19b324dee19d73b1c004565009861a8f64c68b7b9e64dbf", [:rebar3], [], "hexpm", "78eee8bb38f0bee2e73673d71bc75fc6fb01f56f0d23e769a26eee3655487a38"},
   "jsx": {:hex, :jsx, "2.9.0", "d2f6e5f069c00266cad52fb15d87c428579ea4d7d73a33669e12679e203329dd", [:mix, :rebar3], [], "hexpm", "8ee1db1cabafdd578a2776a6aaae87c2a8ce54b47b59e9ec7dab5d7eb71cd8dc"},
   "kafka_protocol": {:hex, :kafka_protocol, "2.3.6", "df076a8ef49fffae3535c805cb00f3a057ce1895e63398bf8a10569eeeac02f8", [:rebar, :rebar3], [{:crc32cer, "0.1.4", [hex: :crc32cer, repo: "hexpm", optional: false]}, {:snappyer, "1.2.5", [hex: :snappyer, repo: "hexpm", optional: false]}], "hexpm", "7cb061fe46babc7fd269d2c0e5b4dba5d1efc4f7dacce85b17a9cca973106b23"},
+  "logger_json": {:hex, :logger_json, "4.1.0", "76037738cd0b71bfb6230c8e3dc505c4f5789bb47e7a2e3d4a0421c6778d48e4", [:mix], [{:ecto, "~> 2.1 or ~> 3.0", [hex: :ecto, repo: "hexpm", optional: true]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0", [hex: :telemetry, repo: "hexpm", optional: true]}], "hexpm", "eab61e32e8efe185dc679785c50cb71a91320b7c94104fa16d8d27d6d5984e95"},
   "makeup": {:hex, :makeup, "1.0.5", "d5a830bc42c9800ce07dd97fa94669dfb93d3bf5fcf6ea7a0c67b2e0e4a7f26c", [:mix], [{:nimble_parsec, "~> 0.5 or ~> 1.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "cfa158c02d3f5c0c665d0af11512fed3fba0144cf1aadee0f2ce17747fba2ca9"},
   "makeup_elixir": {:hex, :makeup_elixir, "0.14.1", "4f0e96847c63c17841d42c08107405a005a2680eb9c7ccadfd757bd31dabccfb", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "f2438b1a80eaec9ede832b5c41cd4f373b38fd7aa33e3b22d9db79e640cbde11"},
   "memoize": {:hex, :memoize, "1.3.2", "f928aea1597b063d148158198a53590c9e5bf8d0c1c8aca8e20b78e566163679", [:mix], [], "hexpm", "c757710fd8afb5a305da997f0a8c7a1cb54dd700af04d3208198553f9b4269c3"},