@opentelemetry/instrumentation-pg

What is @opentelemetry/instrumentation-pg?

@opentelemetry/instrumentation-pg is an npm package that provides automatic instrumentation for the 'pg' (node-postgres) module, enabling the collection of telemetry data such as traces and metrics for PostgreSQL database operations. This helps in monitoring and debugging database interactions in applications.

What are @opentelemetry/instrumentation-pg's main functionalities?

Automatic Tracing

This feature allows automatic tracing of PostgreSQL operations. The code sample demonstrates how to set up the NodeTracerProvider and register the PgInstrumentation to start collecting trace data.

const { NodeTracerProvider } = require('@opentelemetry/node');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { PgInstrumentation } = require('@opentelemetry/instrumentation-pg');

const provider = new NodeTracerProvider();
provider.register();

registerInstrumentations({
  instrumentations: [
    new PgInstrumentation(),
  ],
  tracerProvider: provider,
});

Custom Span Attributes

This feature allows adding custom attributes to spans. The code sample shows how to configure the PgInstrumentation to include additional information such as the number of rows returned in the response.

const { PgInstrumentation } = require('@opentelemetry/instrumentation-pg');

const pgInstrumentation = new PgInstrumentation({
  enhancedDatabaseReporting: true,
  responseHook: (span, responseInfo) => {
    span.setAttribute('db.response.rows', responseInfo.rowCount);
  },
});

Error Handling

This feature allows capturing and reporting errors in database operations. The code sample demonstrates how to set the span status to error if an error occurs during the database operation.

const { PgInstrumentation } = require('@opentelemetry/instrumentation-pg');

const pgInstrumentation = new PgInstrumentation({
  responseHook: (span, responseInfo) => {
    if (responseInfo.error) {
      span.setStatus({ code: 2, message: responseInfo.error.message });
    }
  },
});

Other packages similar to @opentelemetry/instrumentation-pg

@opentelemetry/instrumentation-mysql

@opentelemetry/instrumentation-mysql provides similar functionality for MySQL databases. It allows automatic tracing and collection of telemetry data for MySQL operations, enabling monitoring and debugging of database interactions.

@opentelemetry/instrumentation-mongodb

@opentelemetry/instrumentation-mongodb offers similar capabilities for MongoDB databases. It provides automatic instrumentation for MongoDB operations, helping in the collection of trace data and metrics for monitoring and debugging purposes.

README

OpenTelemetry Postgres Instrumentation for Node.js

This module provides automatic instrumentation for the pgmodule, which may be loaded using the @opentelemetry/sdk-trace-node package and is included in the @opentelemetry/auto-instrumentations-node bundle.

If total installation size is not constrained, it is recommended to use the @opentelemetry/auto-instrumentations-node bundle with @opentelemetry/sdk-node for the most seamless instrumentation experience.

Compatible with OpenTelemetry JS API and SDK 1.0+.

Installation

npm install --save @opentelemetry/instrumentation-pg

Supported Versions

• pg versions >=8.0.3 <9
• pg-pool versions >=2.0.0 <4

Usage

const { PgInstrumentation } = require('@opentelemetry/instrumentation-pg');
const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');

const provider = new NodeTracerProvider();
provider.register();

registerInstrumentations({
  instrumentations: [
    new PgInstrumentation(),
  ],
});

PgInstrumentation contains both pg and pg.Pool so it will be instrumented automatically.

PostgreSQL Instrumentation Options

PostgreSQL instrumentation has few options available to choose from. You can set the following:

Options	Type	Description
enhancedDatabaseReporting	boolean	If true, additional information about query parameters and results will be attached (as attributes) to spans representing database operations
requestHook	PgInstrumentationExecutionRequestHook (function)	Function for adding custom span attributes using information about the query being issued and the db to which it's directed
responseHook	PgInstrumentationExecutionResponseHook (function)	Function for adding custom span attributes from db response
requireParentSpan	boolean	If true, requires a parent span to create new spans (default false)
addSqlCommenterCommentToQueries	boolean	If true, adds sqlcommenter specification compliant comment to queries with tracing context (default false). NOTE: A comment will not be added to queries that already contain -- or /* ... */ in them, even if these are not actually part of comments

Semantic Conventions

Prior to version 0.55.0, this instrumentation created spans and metrics targeting an experimental semantic convention Version 1.27.0.

Database semantic conventions (semconv) were stabilized in v1.34.0, and a migration process was defined. @opentelemetry/instrumentation-pg versions 0.55.0 and later include support for migrating to stable Database semantic conventions, as described below. The intent is to provide an approximate 6 month time window for users of this instrumentation to migrate to the new Database semconv, after which a new minor version will use the new semconv by default and drop support for the old semconv.

To select which semconv version(s) is emitted from this instrumentation, use the OTEL_SEMCONV_STABILITY_OPT_IN environment variable.

• database: emit the new (stable) v1.34.0+ semantics
• database/dup: emit both the old v1.27.0 and the new (stable) v1.34.0+ semantics
• By default, if OTEL_SEMCONV_STABILITY_OPT_IN includes neither of the above tokens, the old v1.27.0 semconv is used.

Attributes collected

v1.27.0 semconv	v1.34.0 semconv	Short Description
db.connection_string	Removed	String used to connect to the database
db.user	Removed	User used to connect to the database
db.name	Removed, integrated into the new db.namespace	The name of the database.
(not included)	db.namespace	The name of the database, fully qualified within the server address and port.
db.statement	db.query.text	The database query being executed.
db.system	db.system.name	The database management system (DBMS) product as identified by the client instrumentation.
net.peer.port	server.port	Remote port number.
net.peer.name	server.address	Remote hostname or similar.

Metrics Exported:

• db.client.operation.duration

Upgrading Semantic Conventions

When upgrading to the new semantic conventions, it is recommended to do so in the following order:

• Upgrade @opentelemetry/opentelemetry-instrumentation-pg to the latest version
• Set OTEL_SEMCONV_STABILITY_OPT_IN=database/dup to emit both old and new semantic conventions
• Modify alerts, dashboards, metrics, and other processes to expect the new semantic conventions
• Set OTEL_SEMCONV_STABILITY_OPT_IN=database to emit only the new semantic conventions

This will cause both the old and new semantic conventions to be emitted during the transition period.

Useful links

• For more information on OpenTelemetry, visit: https://opentelemetry.io/
• For more about OpenTelemetry JavaScript: https://github.com/open-telemetry/opentelemetry-js
• For help or feedback on this project, join us in GitHub Discussions

License

Apache 2.0 - See LICENSE for more information.