fix(instrumentation-redis): Take host and port used for connection (#…

…2072)

* fix(instrumentation-redis): Take host and port used for connection

The Redis client allows specifying connection options in several ways, with
sensible defaults. The following all translate into `127.0.0.1:6379`:

```js
createClient('redis://127.0.0.1:6379');
createClient({ host: '127.0.0.1', port: NaN });
createClient({})
createClient()
```

Redis somewhat normalises these separate options into its `options` member, and
stores the properties it uses to connect to the server in
`connection_options`. Examples of the difference between the two in the examples
preceding (slightly redacted for ease of reading):

```js
createClient('redis://127.0.0.1:6379');
// options = { port: '6379', host: '127.0.0.1' }
// connection_options = { port: 6379, host: '127.0.0.1', family: 4 }

createClient({ host: '127.0.0.1', port: NaN });
// options = { host: '127.0.0.1', port: NaN }
// connection_options = { port: 6379, host: '127.0.0.1', family: 4 }

createClient()
// options = { host: undefined }
// connection_options = { port: 6379, host: '127.0.0.1', family: 4 }
```

The instrumentation before this commit looks at the `options` property, which
contains caller-supplied values before they're fully normalised and smoothed
over by Redis. This means that for these weird cases, the instrumentation would
populate `NET_PEER_NAME` and `NET_PEER_PORT` with erroneous values.

This commit has the instrumentation the values the Redis client uses to connect
to the server, mirroring actual use.

* test(instrumentation-redis): Explicitly expect for a numeric port

---------

Co-authored-by: Amir Blum <amirgiraffe@gmail.com>

plugins/node/opentelemetry-instrumentation-redis/src/internal-types.ts

@@ -14,9 +14,9 @@
  * limitations under the License.
  */
 export interface RedisPluginClientTypes {
-  options?: {
-    host: string;
-    port: string;
+  connection_options?: {
+    port?: string;
+    host?: string;
   };
 
   address?: string;

plugins/node/opentelemetry-instrumentation-redis/src/utils.ts

@@ -111,10 +111,10 @@ export const getTracedInternalSendCommand = (
     );
 
     // Set attributes for not explicitly typed RedisPluginClientTypes
-    if (this.options) {
+    if (this.connection_options) {
       span.setAttributes({
-        [SEMATTRS_NET_PEER_NAME]: this.options.host,
-        [SEMATTRS_NET_PEER_PORT]: this.options.port,
+        [SEMATTRS_NET_PEER_NAME]: this.connection_options.host,
+        [SEMATTRS_NET_PEER_PORT]: this.connection_options.port,
       });
     }
     if (this.address) {

plugins/node/opentelemetry-instrumentation-redis/test/redis.test.ts

@@ -51,7 +51,7 @@ const memoryExporter = new InMemorySpanExporter();
 
 const CONFIG = {
   host: process.env.OPENTELEMETRY_REDIS_HOST || 'localhost',
-  port: process.env.OPENTELEMETRY_REDIS_PORT || '63790',
+  port: Number(process.env.OPENTELEMETRY_REDIS_PORT || 63790),
 };
 
 const URL = `redis://${CONFIG.host}:${CONFIG.port}`;