fix: simplify resource implementation

Author: mrstork

package-lock.json

@@ -120,7 +120,6 @@
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/core": "1.30.1",
     "@opentelemetry/instrumentation": "^0.203.0",
-    "@opentelemetry/resources": "1.30.1",
     "@opentelemetry/sdk-trace-node": "1.30.1"
   }
 }

packages/otel/package.json

@@ -1,6 +1,7 @@
 import { type SpanProcessor } from '@opentelemetry/sdk-trace-node'
 import type { Instrumentation } from '@opentelemetry/instrumentation'
 import { GET_TRACER, SHUTDOWN_TRACERS } from '../constants.js'
+import { Resource } from '../resource.ts'
 
 export interface TracerProviderOptions {
   serviceName: string
@@ -20,7 +21,6 @@ export const createTracerProvider = async (options: TracerProviderOptions) => {
   const runtimeVersion = nodeVersion.slice(1)
 
   const { W3CTraceContextPropagator } = await import('@opentelemetry/core')
-  const { Resource } = await import('@opentelemetry/resources')
   const { NodeTracerProvider } = await import('@opentelemetry/sdk-trace-node')
   const { registerInstrumentations } = await import('@opentelemetry/instrumentation')
 

packages/otel/src/bootstrap/main.ts

@@ -0,0 +1,89 @@
+import { Attributes } from '@opentelemetry/api'
+
+export type ResourceAttributes = Attributes
+
+/**
+ * An interface that represents a resource. A Resource describes the entity for which signals (metrics or trace) are
+ * collected.
+ *
+ */
+export interface IResource {
+  /**
+   * Check if async attributes have resolved. This is useful to avoid awaiting
+   * waitForAsyncAttributes (which will introduce asynchronous behavior) when not necessary.
+   *
+   * @returns true if the resource "attributes" property is not yet settled to its final value
+   */
+  asyncAttributesPending?: boolean
+
+  /**
+   * @returns the Resource's attributes.
+   */
+  readonly attributes: ResourceAttributes
+
+  /**
+   * Returns a promise that will never be rejected. Resolves when all async attributes have finished being added to
+   * this Resource's attributes. This is useful in exporters to block until resource detection
+   * has finished.
+   */
+  waitForAsyncAttributes?(): Promise<void>
+
+  /**
+   * Returns a new, merged {@link Resource} by merging the current Resource
+   * with the other Resource. In case of a collision, other Resource takes
+   * precedence.
+   *
+   * @param other the Resource that will be merged with this.
+   * @returns the newly merged Resource.
+   */
+  merge(other: IResource | null): IResource
+}
+
+/**
+ * A Resource describes the entity for which a signals (metrics or trace) are
+ * collected.
+ */
+export class Resource implements IResource {
+  private _attributes?: ResourceAttributes
+  private _syncAttributes?: ResourceAttributes
+
+  constructor(
+    /**
+     * A dictionary of attributes with string keys and values that provide
+     * information about the entity as numbers, strings or booleans
+     */
+    attributes: ResourceAttributes,
+  ) {
+    this._attributes = attributes
+    this._syncAttributes = this._attributes ?? {}
+  }
+
+  get attributes(): ResourceAttributes {
+    return this._attributes ?? {}
+  }
+
+  /**
+   * Returns a promise that will never be rejected. Resolves when all async attributes have finished being added to
+   * this Resource's attributes. This is useful in exporters to block until resource detection
+   * has finished.
+   */
+  async waitForAsyncAttributes?(): Promise<void> {}
+
+  /**
+   * Returns a new, merged {@link Resource} by merging the current Resource
+   * with the other Resource. In case of a collision, other Resource takes
+   * precedence.
+   *
+   * @param other the Resource that will be merged with this.
+   * @returns the newly merged Resource.
+   */
+  merge(other: IResource | null): IResource {
+    if (!other) return this
+
+    // SpanAttributes from other resource overwrite attributes from this resource.
+    return new Resource({
+      ...this._syncAttributes,
+      ...(other as Resource)._syncAttributes,
+    })
+  }
+}