---
title: Go agent code-level metrics configuration
source: https://docs.newrelic.com/docs/apm/agents/go-agent/configuration/go-agent-code-level-metrics-config
---

Code-level metrics allow developers using the [New Relic CodeStream extension](https://docs.newrelic.com/docs/codestream/observability/code-level-metrics) to see APM data displayed contextually in their IDE, alongside individual methods in the code. This allows developers to be more proactive about addressing performance issues as they write and review code.

When you enable code-level metrics, the Go agent will attach attributes to trace data. These attributes show the location in your application source code responsible for the actions instrumented by those traces. The data you can see includes:

-   Source file name
-   Source file line number
-   Function name
-   Namespace

Take a look at the Go agent configuration settings to help you control the collection of code-level metrics. After you complete the configuration, if you need help finding the data, see [View your metrics](#view-metrics). If you want more control over how the metrics are collected, see [Go agent code-level metrics instrumentation](https://docs.newrelic.com/docs/apm/agents/go-agent/instrumentation/go-agent-code-level-metrics-instrument).

> #### ⚠️ IMPORTANT
>
> Code-level metrics are available for Go agent version 3.18.0 or higher, and enabled by default for version 3.24.0 and higher. To enable it, you must add `newrelic.ConfigCodeLevelMetricsEnabled(true)` to your application's configuration as explained below.

## Configuration methods [#config]

When calling `newrelic.NewApplication` to configure the Go agent in your application, you can enable code-level metrics by including the `newrelic.ConfigCodeLevelMetricsEnabled` option, like so:

```go
app, err := newrelic.NewApplication(
   newrelic.ConfigAppName("Your Application Name"),
   newrelic.ConfigLicense(os.Getenv("NEW_RELIC_LICENSE_KEY")),
   newrelic.ConfigCodeLevelMetricsEnabled(true),
)
```

With that simple step, the Go agent will add the source code context information in the following agent attributes on transactions:

| Name             | Description                                                                                                                                                                                                                                    |
| ---------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `code.function`  | The name of the function which started the transaction. Note that this may be automatically generated by the Go compiler in some cases.                                                                                                        |
| `code.namespace` | The package/namespace where the function is located. The combination of `code.namespace` and `code.function`, joined with a delimiter such as a dot (`.`), is expected to uniquely identify the function.                                      |
| `code.filepath`  | The pathname of the source file containing the function being reported. Normally this is the full, absolute pathname; see below for a configuration option which allows you to change this to a relative path.                                 |
| `code.lineno`    | The line number within `code.filepath` where the transaction was started. See [the instrumentation guide](https://docs.newrelic.com/docs/apm/agents/go-agent/instrumentation/go-agent-code-level-metrics-instrument) for ways to control this. |

There are additional configuration options you may wish to use to further refine the collection of code-level metrics in your application.

**Errors inbox configuration**

Setting one of the following tags will help you identify which versions of your software are producing the errors.

-   `NEW_RELIC_METADATA_SERVICE_VERSION` creates `tags.service.version` on event data containing the version of your code that is deployed, in many cases a semantic version such as 1.2.3, but not always.
-   `NEW_RELIC_METADATA_RELEASE_TAG ` creates `tags.releaseTag` on event data containing the release tag (such as v0.1.209 or release-209).
-   `NEW_RELIC_METADATA_COMMIT` creates `tags.commit` on event data containing the commit SHA. The entire SHA can be used or just the first seven characters (e.g., 734713b).

    An upcoming release of errors inbox will automatically track which versions of your software are producing errors. Any version data will also be displayed in [CodeStream](https://docs.newrelic.com/docs/codestream/how-use-codestream/performance-monitoring/#buildsha).

**Identify instrumented packages**

By default, with code-level metrics enabled, the agent will ignore functions in the call stack which it believes to be internal
to the agent itself, to ensure that the function reported is the one intended, even though functions inside the agent will have
been called to get into the code-level metrics instrumentation code. By default, it does this by ignoring any functions whose
package name begins with `github.com/newrelic/go-agent/`. You can change this to any arbitrary list of names by setting your own
`IgnoredPrefixes` value.

To accomplish this, do one of the following:

-   If configuring via the `NewApplication` function, add a `ConfigCodeLevelMetricsIgnoredPrefixes` option, passing any number of prefix strings as separate string arguments:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigCodeLevelMetricsIgnoredPrefixes("github.com/some/other/name/"),
    )
    ```

-   If configuring via environment variables, set `NEW_RELIC_CODE_LEVEL_METRICS_IGNORED_PREFIXES` to the desired prefix (or a comma-separated list of prefixes):

    ```ini
    NEW_RELIC_CODE_LEVEL_METRICS_IGNORED_PREFIXES="github.com/some/other/name/"
    ```

    Don't forget to also include the `newrelic.ConfigFromEnvironment()` option when setting up the application:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigFromEnvironment(),
    )
    ```

-   It is also possible to directly set the `CodeLevelMetrics.IgnoredPrefixes` member of the `Config` struct (which is a `[]string` value), but we recommend using one of the above-mentioned methods instead of directly manipulating the `Config` structure.

    > #### ⚠️ IMPORTANT
    >
    > In Go Agent versions prior to 3.20.0, this option was named with in the singular form rather than plural (i.e., `ConfigCodeLevelMetricsIgnoredPrefix`). These names are deprecated and the ones documented here should be used. The older names are also still supported for backward compatibility.

**Redact ignored module prefixes**

If, for reasons such as confidentiality, you choose to ignore some modules via
`ConfigCodeLevelMetricsIgnoredPrefixes` option, you may also wish to redact the list of such prefixes
from the agent's reported configuration data as well.

This is accomplished by setting the `ConfigCodeLevelMetricsRedactIgnoredPrefixes` option. If given a `true` value,
your list of ignored prefixes will not be shown in the configuration data that are reported by the agent. Otherwise,
they will be reported.

Do one of the following:

-   If configuring via the `NewApplication` function, add a `ConfigCodeLevelMetricsRedactIgnoredPrefixes` option:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigCodeLevelMetricsRedactIgnoredPrefixes(true),
    )
    ```

-   If configuring via environment variables, set `NEW_RELIC_CODE_LEVEL_METRICS_REDACT_IGNORED_PREFIXES`:

    ```ini
    NEW_RELIC_CODE_LEVEL_METRICS_REDACT_IGNORED_PREFIXES=true
    ```

    Don't forget to also include the `newrelic.ConfigFromEnvironment` option when setting up the application:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigFromEnvironment(),
    )
    ```

    > #### ⚠️ IMPORTANT
    >
    > This redaction option is available in Go Agent versions 3.20.0 and later.

**Truncate source path prefix**

By default, with code-level metrics enabled, the agent will report the full pathname of each source file. However, this may
not be desired. For example, you may wish to only report application paths relative to the root of the project source
tree, allowing data to be correlated between instances regardless of where they are installed in the filesystem.

To accomplish this, specify a string that indicates the start of your local project source path. If that prefix is found
in a source file pathname, everything that appears before it will be removed. For example, if the path prefix string
is set to `myproject/src` then `/usr/local/projects/myproject/src/widget/main.go` would be reported in the code-level metrics
as `myproject/src/widget/main.go`.

If you have multiple path prefixes you wish to use, simply list all of their names as separate parameters.

If `PathPrefixes` is empty, or a source file path doesn't contain any of your prefix strings at all, the full pathname will be reported.

Do one of the following:

-   If configuring via the `NewApplication` function, add a `ConfigCodeLevelMetricsPathPrefixes` option:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigCodeLevelMetricsPathPrefixes("myprojects/src/", "otherproject/src/"),
    )
    ```

-   If configuring via environment variables, set `NEW_RELIC_CODE_LEVEL_METRICS_PATH_PREFIXES` to the desired prefix(es):

    ```ini
    NEW_RELIC_CODE_LEVEL_METRICS_PATH_PREFIXES="myprojects/src/,otherproject/src/"
    ```

    Don't forget to also include the `newrelic.ConfigFromEnvironment` option when setting up the application:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigFromEnvironment(),
    )
    ```

    > #### ⚠️ IMPORTANT
    >
    > In Go Agent versions prior to 3.20.0, this option was named with in the singular form rather than plural (i.e., `ConfigCodeLevelMetricsPathPrefix`). These names are deprecated and the ones documented here should be used. The older names are also still supported for backward compatibility.

**Redact source path prefixes**

If, for reasons such as confidentiality, you choose to shorten reported source pathnames via the
`ConfigCodeLevelMetricsPathPrefixes` option, you may also wish to redact the list of path prefixes
from the agent's reported configuration data as well.

This is accomplished by setting the `ConfigCodeLevelMetricsRedactPathPrefixes` option. If given a `true` value,
your list of path prefixes will not be shown in the configuration data that are reported by the agent. Otherwise,
they will be reported.

Do one of the following:

-   If configuring via the `NewApplication` function, add a `ConfigCodeLevelMetricsRedactPathPrefixes` option:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigCodeLevelMetricsPathPrefixes("myprojects/src/", "otherproject/src/"),
       newrelic.ConfigCodeLevelMetricsRedactPathPrefixes(true),
    )
    ```

-   If configuring via environment variables, set `NEW_RELIC_CODE_LEVEL_METRICS_REDACT_PATH_PREFIXES`:

    ```ini
    NEW_RELIC_CODE_LEVEL_METRICS_REDACT_PATH_PREFIXES=true
    ```

    Don't forget to also include the `newrelic.ConfigFromEnvironment` option when setting up the application:

    ```go
    app, err := newrelic.NewApplication(
       newrelic.ConfigAppName("Your Application Name"),
       newrelic.ConfigLicense("YOUR_NEW_RELIC_LICENSE_KEY"),
       newrelic.ConfigCodeLevelMetricsEnabled(true),
       newrelic.ConfigFromEnvironment(),
    )
    ```

    > #### ⚠️ IMPORTANT
    >
    > This redaction option is available in Go Agent versions 3.20.0 and later.

## View your metrics [#view-metrics]

Once you've configured code-level metrics, you can see your data in the New Relic UI. Here's one way you can see traces for a particular service:

1.  Go to **[one.newrelic.com > All capabilities](https://one.newrelic.com/all-capabilities) > APM & services**.
2.  Click your entity (service).
3.  In the left pane's **Monitor** section, click **Transactions**.
4.  Under **Transaction traces**, click on an individual trace.
5.  Look under **Agent attributes** for the four attributes beginning with `code.`.