feat: Add opentelemetry initial declarative configuration

Cargo.toml

@@ -1,6 +1,8 @@
 [workspace]
 members = [
     "opentelemetry-aws",
+    "opentelemetry-config",
+    "opentelemetry-config-stdout",
     "opentelemetry-contrib",
     "opentelemetry-datadog",
     "opentelemetry-etw-logs",

opentelemetry-config-stdout/CHANGELOG.md

@@ -0,0 +1,9 @@
+# Changelog
+
+## vNext
+
+## v0.1.0
+
+### Added
+
+- Initial declarative configuration for stdout (console)

opentelemetry-config-stdout/CODEOWNERS

@@ -0,0 +1,5 @@
+# Code owners file.
+# This file controls who is tagged for review for any given pull request.
+
+# For anything not explicitly taken by someone else:
+*  @open-telemetry/rust-approvers

opentelemetry-config-stdout/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "opentelemetry-config-stdout"
+version = "0.1.0"
+description = "Declarative configuration for OpenTelemetry SDK using console (stdout) configuration"
+license = "Apache-2.0"
+edition = "2021"
+rust-version = "1.75.0"
+
+[dependencies]
+opentelemetry-config = { path = "../opentelemetry-config" }
+opentelemetry_sdk = { version = "0.31.0" }
+opentelemetry-stdout = { version = "0.31.0" }
+serde = { version = "1.0", features = ["derive"] }
+serde_yaml = { version = "0.9.34" }
+
+[lints]
+workspace = true

opentelemetry-config-stdout/README.md

@@ -0,0 +1,128 @@
+# OpenTelemetry Declarative Configuration for stdout (console)
+
+![OpenTelemetry — An observability framework for cloud-native software.][splash]
+
+[splash]: https://raw.githubusercontent.com/open-telemetry/opentelemetry-rust/main/assets/logo-text.png
+
+Declarative configuration for applications instrumented with [`OpenTelemetry`]. 
+
+[`OpenTelemetry`]: https://crates.io/crates/opentelemetry
+
+## Overview
+
+This crate provides a declarative configuration extension for OpenTelemetry that enables stdout (console) metric exports. It integrates with the `opentelemetry-config` crate to allow YAML-based configuration of the console exporter.
+
+### Features
+
+- Console/stdout metrics exporter configuration via YAML
+- Support for both Delta and Cumulative temporality
+- Integration with OpenTelemetry declarative configuration
+- Simple registration API for declarative configuration
+
+## Installation
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+opentelemetry-config-stdout = "0.1.0"
+```
+
+## Quick Start
+
+### 1. Create a YAML Configuration File
+
+Create a file named `otel-config.yaml`:
+
+```yaml
+metrics:
+  readers:
+    - periodic:
+        exporter:
+          console:
+            temporality: delta
+
+resource:
+  service.name: "my-service"
+  service.version: "1.0.0"
+```
+
+### 2. Load and Apply Configuration
+
+```rust
+use opentelemetry_config::{ConfigurationProvidersRegistry, providers::TelemetryProvider};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Create configuration registry and register console exporter
+    let mut registry = ConfigurationProvidersRegistry::new();
+    let metrics_registry = registry.metrics_mut();
+    metrics_registry.register_periodic_exporter_factory(
+        "console".to_string(),
+        opentelemetry_config_stdout::register_console_exporter
+    );
+
+    // Load configuration from YAML file
+    let telemetry_provider = TelemetryProvider::new();
+    let providers = telemetry_provider
+        .configure_from_yaml_file(&registry, "otel-config.yaml")?;
+
+    // Use the configured providers
+    if let Some(meter_provider) = providers.meter_provider() {
+        // Your application code here
+
+        // Shutdown the created meter provider when done.
+        meter_provider.shutdown()?;
+    }
+
+    Ok(())
+}
+```
+
+## Examples
+
+### Console Exporter Example
+
+See the [examples/console](examples/console) directory for a complete working example that demonstrates:
+
+- Setting up a console exporter factory
+- Loading configuration from a YAML file
+- Configuring a meter provider
+- Proper shutdown handling
+
+To run the example:
+
+```bash
+cd examples/console
+cargo run -- --file ../metrics_console.yaml
+```
+
+## Configuration Schema
+
+### Metrics Configuration
+
+```yaml
+metrics:
+  readers:
+    - periodic:
+        exporter:
+          console:
+            temporality: delta  # or cumulative
+```
+
+#### Configuration Options
+
+- **`temporality`** (optional): Controls how metrics are aggregated
+  - `delta`: Reports the change since the last export (useful for rate-based metrics like requests per second)
+  - `cumulative`: Reports the total accumulated value since the start (default, useful for gauges and cumulative counters)
+
+## Contributing
+
+Contributions are welcome! Please feel free to submit issues or pull requests.
+
+## License
+
+This project is licensed under the Apache-2.0 license.
+
+## Release Notes
+
+You can find the release notes (changelog) [here](CHANGELOG.md).

opentelemetry-config-stdout/examples/console/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "opentelemetry-config-console-example"
+version = "0.1.0"
+description = "Declarative configuration for OpenTelemetry SDK example using console configuration"
+license = "Apache-2.0"
+edition = "2021"
+rust-version = "1.75.0"
+
+[workspace]
+
+[dependencies]
+opentelemetry-config-stdout = { path = "../../" }
+opentelemetry-config = { path = " ../../../../../opentelemetry-config" }

opentelemetry-config-stdout/examples/console/src/main.rs

@@ -0,0 +1,59 @@
+//! # Example OpenTelemetry Config Console
+//!
+//! This example demonstrates how to configure OpenTelemetry Metrics
+//! using the OpenTelemetry Config crate with a Console Exporter.
+
+use opentelemetry_config::{providers::TelemetryProvider, ConfigurationProvidersRegistry};
+
+use std::env;
+
+pub fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let args: Vec<String> = env::args().collect();
+
+    if args.len() == 1 || (args.len() > 1 && args[1] == "--help") {
+        println!("Usage: cargo run -- --file ../metrics_console.yaml");
+        println!("This example demonstrates how to configure OpenTelemetry Metrics using the OpenTelemetry Config crate with a Console Exporter.");
+        return Ok(());
+    }
+    if args.len() < 3 || args[1] != "--file" {
+        println!("Error: Configuration file path not provided.");
+        println!("Usage: cargo run -- --file ../metrics_console.yaml");
+        return Ok(());
+    }
+    let config_file = &args[2];
+
+    // Setup configuration registry with console exporter provider.
+    let mut configuration_providers_registry = ConfigurationProvidersRegistry::new();
+    let metrics_registry = configuration_providers_registry.metrics_mut();
+    metrics_registry.register_periodic_exporter_factory(
+        "console".to_string(),
+        opentelemetry_config_stdout::register_console_exporter,
+    );
+
+    let telemetry_provider = TelemetryProvider::new();
+    let providers = telemetry_provider
+        .configure_from_yaml_file(&configuration_providers_registry, config_file)?;
+
+    if let Some(meter_provider) = providers.meter_provider() {
+        println!("Meter provider is configured. Shutting it down...");
+        meter_provider.shutdown()?;
+    } else {
+        println!("No Meter Provider configured.");
+    }
+
+    if let Some(logs_provider) = providers.logs_provider() {
+        println!("Logs provider is configured. Shutting it down...");
+        logs_provider.shutdown()?;
+    } else {
+        println!("No Logs Provider configured.");
+    }
+
+    if let Some(traces_provider) = providers.traces_provider() {
+        println!("Traces provider is configured. Shutting it down...");
+        traces_provider.shutdown()?;
+    } else {
+        println!("No Traces Provider configured.");
+    }
+
+    Ok(())
+}

opentelemetry-config-stdout/examples/metrics_console.yaml

@@ -0,0 +1,9 @@
+metrics:
+    readers:
+        - periodic:
+            exporter:
+                console:
+                    temporality: delta
+resource:
+    service.name: "test-service"
+    service.version: "1.0.0"