Elixir Opentelemetry Instrumentation

This document contains OpenTelemetry instrumentation instructions for Elixir Phoenix + Ecto framework.

Send Traces to SigNoz Cloud

Based on your application environment, you can choose the setup below to send traces to SigNoz Cloud.

    {:opentelemetry_exporter, "~> 1.6"},
    {:opentelemetry_api, "~> 1.2"},
    {:opentelemetry, "~> 1.3"},
    {:opentelemetry_semantic_conventions, "~> 0.2"},
    {:opentelemetry_cowboy, "~> 0.2.1"},
    {:opentelemetry_phoenix, "~> 1.1"},
    {:opentelemetry_ecto, "~> 1.1"}

    :opentelemetry_cowboy.setup()
    OpentelemetryPhoenix.setup(adapter: :cowboy2)
    OpentelemetryEcto.setup([:YOUR_APP_NAME, :repo])

# application.ex
@impl true
def start(_type, _args) do
  :opentelemetry_cowboy.setup()
  OpentelemetryPhoenix.setup(adapter: :cowboy2)
  OpentelemetryEcto.setup([:demo, :repo])

end

config :opentelemetry, :resource, service: %{name: "YOUR_APP_NAME"}

config :opentelemetry, :processors,
  otel_batch_processor: %{
    exporter: {
      :opentelemetry_exporter,
      %{
        endpoints: ["https://ingest.{region}.signoz.cloud:443"],
        headers: [
          {"signoz-ingestion-key", SIGNOZ_ACCESS_TOKEN}
        ]
      }
    }
  }

    {:opentelemetry_exporter, "~> 1.6"},
    {:opentelemetry_api, "~> 1.2"},
    {:opentelemetry, "~> 1.3"},
    {:opentelemetry_semantic_conventions, "~> 0.2"},
    {:opentelemetry_cowboy, "~> 0.2.1"},
    {:opentelemetry_phoenix, "~> 1.1"},
    {:opentelemetry_ecto, "~> 1.1"}

    :opentelemetry_cowboy.setup()
    OpentelemetryPhoenix.setup(adapter: :cowboy2)
    OpentelemetryEcto.setup([:YOUR_APP_NAME, :repo])

# application.ex
@impl true
def start(_type, _args) do
  :opentelemetry_cowboy.setup()
  OpentelemetryPhoenix.setup(adapter: :cowboy2)
  OpentelemetryEcto.setup([:demo, :repo])

end

config :opentelemetry, :resource, service: %{name: "YOUR_APP_NAME"}

config :opentelemetry, :processors,
    otel_batch_processor: %{
      exporter: 
      {:opentelemetry_exporter, 
      %{endpoints: ["http://localhost:4318"]}
      }
  }

Send Traces to Self-Hosted SigNoz

We’ll focus on instrumenting one of the most common combos of the Elixir world: Phoenix + Ecto.

Step 1: Add dependencies

The first step to instrument your Elixir application with OpenTelemetry is to add the required dependencies to your mix.exs file and fetch them with mix deps.get

{:opentelemetry, "~> 1.0.3"},
{:opentelemetry_exporter, "~> 1.0.3"},
{:opentelemetry_phoenix, "~> 1.0.0"},
{:opentelemetry_ecto, "~> 1.0.0"}

Step 2: Configure Elixir application

Then we need to configure our application to export telemetry data. There are two things that you need to set:

• YOUR_APP_NAME
  You can put your application or service name here for identification.
• OTEL Collector endpoint
  The OTEL collector comes bundled with SigNoz installation. Since, we installed SigNoz on our local machine, the endpoint is http://localhost:4318.

config :opentelemetry, :resource, service: %{name: "YOUR_APP_NAME"}

config :opentelemetry, :processors,
  otel_batch_processor: %{
    exporter: {
      :opentelemetry_exporter,
      %{endpoints: ["http://localhost:4318"]}
    }
  }

Step 3: Initialize telemetry handlers

As it is documented in the opentelemetry_phoenix and opentelemetry_ecto hexdocs.pm pages, we need to initialize both telemetry handlers.

OpentelemetryPhoenix.setup()
OpentelemetryEcto.setup([:your_app_name, :repo])

:your_app_name should be replaced by your app name and congratulations, you have instrumented your application with OpenTelemetry.

Sample Examples

Here's a tutorial with step by step guide on how to install SigNoz and start monitoring a sample Elixir app.

Thanks to our community member Ricardo for creating this guide.

Frequently Asked Questions

1. How to find what to use in IP of SigNoz if I have installed SigNoz in Kubernetes cluster?

   Based on where you have installed your application and where you have installed SigNoz, you need to find the right value for this. Please use this grid to find the value you should use for IP of SigNoz

2. I am sending data from my application to SigNoz, but I don't see any events or graphs in the SigNoz dashboard. What should I do?

   This could be because of one of the following reasons:

   1. Your application is generating telemetry data, but not able to connect with SigNoz installation

      Please use this troubleshooting guide to find if your application is able to access SigNoz installation and send data to it.

   2. Your application is not actually generating telemetry data

      Please check if the application is generating telemetry data first. You can use Console Exporter to just print your telemetry data in console first. Join our Slack Community if you need help on how to export your telemetry data in console

   3. Your SigNoz installation is not running or behind a firewall

      Please double check if the pods in SigNoz installation are running fine. docker ps or kubectl get pods -n platform are your friends for this.

What Cloud Endpoint Should I Use?

The primary method for sending data to SigNoz Cloud is through OTLP exporters. You can either send the data directly from your application using the exporters available in SDKs/language agents or send the data to a collector agent, which batches/enriches telemetry and sends it to the Cloud.

My Collector Sends Data to SigNoz Cloud

Using gRPC Exporter

The endpoint should be ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu. Note that the exporter endpoint doesn't require a scheme for the gRPC exporter in the collector.

# Sample config with `us` region
exporters:
    otlp:
        endpoint: "ingest.us.signoz.cloud:443"
        tls:
            insecure: false
        headers:
            "signoz-ingestion-key": "<SIGNOZ_INGESTION_KEY>"

Using HTTP Exporter

The endpoint should be https://ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu. Note that the endpoint includes the scheme https for the HTTP exporter in the collector.

# Sample config with `us` region
exporters:
    otlphttp:
        endpoint: "https://ingest.us.signoz.cloud:443"
        tls:
            insecure: false
        headers:
            "signoz-ingestion-key": "<SIGNOZ_INGESTION_KEY>"

My Application Sends Data to SigNoz Cloud

The endpoint should be configured either with environment variables or in the SDK setup code.

Using Environment Variables

Using gRPC Exporter

Examples with us region

• OTEL_EXPORTER_OTLP_PROTOCOL=grpc OTEL_EXPORTER_OTLP_ENDPOINT=https://ingest.us.signoz.cloud:443 OTEL_EXPORTER_OTLP_HEADERS=signoz-ingestion-key=<SIGNOZ_INGESTION_KEY>

Using HTTP Exporter

• OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf OTEL_EXPORTER_OTLP_ENDPOINT=https://ingest.us.signoz.cloud:443 OTEL_EXPORTER_OTLP_HEADERS=signoz-ingestion-key=<SIGNOZ_INGESTION_KEY>

Configuring Endpoint in Code

Please refer to the agent documentation.

Sending Data from a Third-Party Service

The endpoint configuration here depends on the export protocol supported by the third-party service. They may support either gRPC, HTTP, or both. Generally, you will need to adjust the host and port. The host address should be ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu, and port 443 should be used.