opentelemetry-collector: init

examples/opentelemetry-collector/.test.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+set -ex
+
+endpoint="http://localhost:13133/"
+
+timeout 20 bash -c "until curl $endpoint 2>/dev/null; do sleep 0.5; done"
+curl -s "$endpoint" | grep "Server available"

examples/opentelemetry-collector/devenv.nix

@@ -0,0 +1,62 @@
+{ ... }:
+
+{
+  services.clickhouse.enable = true;
+
+  # Wait for clickhouse to come up
+  processes.opentelemetry-collector.process-compose = {
+    depends_on.clickhouse-server.condition = "process_healthy";
+  };
+
+  services.opentelemetry-collector = {
+    enable = true;
+
+    # Or use a raw YAML file:
+    # `services.opentelemetry-collector.configFile = pkgs.writeTextFile "otel-config.yaml" "...";`
+    settings = {
+      receivers = {
+        otlp = {
+          protocols = {
+            grpc = { };
+            http = { };
+          };
+        };
+      };
+
+      processors = {
+        batch = {
+          timeout = "5s";
+          send_batch_size = 100000;
+        };
+      };
+
+      exporters = {
+        clickhouse = {
+          endpoint = "tcp://127.0.0.1:9000?dial_timeout=10s&compress=lz4";
+          database = "otel";
+          ttl_days = 3;
+          logs_table_name = "otel_logs";
+          traces_table_name = "otel_traces";
+          metrics_table_name = "otel_metrics";
+          timeout = "5s";
+          retry_on_failure = {
+            enabled = true;
+            initial_interval = "5s";
+            max_interval = "30s";
+            max_elapsed_time = "300s";
+          };
+        };
+      };
+
+      service = {
+        pipelines = {
+          traces = {
+            receivers = [ "otlp" ];
+            processors = [ "batch" ];
+            exporters = [ "clickhouse" ];
+          };
+        };
+      };
+    };
+  };
+}

src/modules/services/opentelemetry-collector.nix

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+{ pkgs, config, lib, ... }:
+
+let
+  cfg = config.services.opentelemetry-collector;
+  types = lib.types;
+
+  settingsFormat = pkgs.formats.yaml { };
+
+  defaultSettings = {
+    extensions = {
+      health_check = {
+        endpoint = "localhost:13133";
+      };
+    };
+    service = {
+      extensions = [ "health_check" ];
+    };
+  };
+
+  otelConfig =
+    if cfg.configFile == null
+    then settingsFormat.generate "otel-config.yaml" cfg.settings
+    else cfg.configFile;
+in
+{
+  options.services.opentelemetry-collector = {
+    enable = lib.mkEnableOption "opentelemetry-collector";
+
+    package = lib.mkOption {
+      type = types.package;
+      description = "The OpenTelemetry Collector package to use";
+      default = pkgs.opentelemetry-collector-contrib;
+      defaultText = lib.literalExpression "pkgs.opentelemetry-collector-contrib";
+    };
+
+    configFile = lib.mkOption {
+      type = types.nullOr types.path;
+      description = ''
+        Override the configuration file used by OpenTelemetry Collector.
+        By default, a configuration is generated from `services.opentelemetry-collector.settings`.
+
+        If overriding, enable the `health_check` extension to allow process-compose to check whether the Collector is ready.
+        Otherwise, disable the readiness probe by setting `processes.opentelemetry-collector.process-compose.readiness_probe = {};`.
+      '';
+      default = null;
+      example = lib.literalExpression ''
+        pkgs.writeTextFile { name = "otel-config.yaml"; text = "..."; }
+      '';
+    };
+
+    settings = lib.mkOption {
+      type = types.submodule ({ freeformType = settingsFormat.type; } // defaultSettings);
+      description = ''
+        OpenTelemetry Collector configuration.
+        Refer to https://opentelemetry.io/docs/collector/configuration/
+        for more information on how to configure the Collector.
+      '';
+      defaultText = defaultSettings;
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    processes.opentelemetry-collector = {
+      exec = "${lib.getExe cfg.package} --config ${otelConfig}";
+
+      process-compose = {
+        readiness_probe = {
+          http_get = {
+            host = "localhost";
+            scheme = "http";
+            path = "/";
+            port = 13133;
+          };
+          initial_delay_seconds = 2;
+          period_seconds = 10;
+          timeout_seconds = 5;
+          success_threshold = 1;
+          failure_threshold = 3;
+        };
+        availability.restart = "on_failure";
+      };
+    };
+  };
+}