clarify code function name (#1944)

Co-authored-by: Christophe Kamphaus <christophe.kamphaus@gmail.com>
Co-authored-by: Liudmila Molkova <limolkova@microsoft.com>
Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>

Author: 4 people

.chloggen/1646.yaml

@@ -0,0 +1,5 @@
+change_type: breaking
+component: code
+note: "`code.function.name` value should contain the fully qualified function name, `code.namespace` is now deprecated"
+issues: [1677]
+subtext:

docs/attributes-registry/code.md

@@ -14,18 +14,34 @@ These attributes provide context about source code
 |---|---|---|---|---|
 | <a id="code-column-number" href="#code-column-number">`code.column.number`</a> | int | The column number in `code.file.path` best representing the operation. It SHOULD point within the code unit named in `code.function.name`. | `16` | ![Development](https://img.shields.io/badge/-development-blue) |
 | <a id="code-file-path" href="#code-file-path">`code.file.path`</a> | string | The source code file name that identifies the code unit as uniquely as possible (preferably an absolute file path). | `/usr/local/MyApplication/content_root/app/index.php` | ![Development](https://img.shields.io/badge/-development-blue) |
-| <a id="code-function-name" href="#code-function-name">`code.function.name`</a> | string | The method or function name, or equivalent (usually rightmost part of the code unit's name). | `serveRequest` | ![Development](https://img.shields.io/badge/-development-blue) |
+| <a id="code-function-name" href="#code-function-name">`code.function.name`</a> | string | The method or function fully-qualified name without arguments. The value should fit the natural representation of the language runtime, which is also likely the same used within `code.stacktrace` attribute value. [1] | `com.example.MyHttpService.serveRequest`; `GuzzleHttp\Client::transfer`; `fopen` | ![Development](https://img.shields.io/badge/-development-blue) |
 | <a id="code-line-number" href="#code-line-number">`code.line.number`</a> | int | The line number in `code.file.path` best representing the operation. It SHOULD point within the code unit named in `code.function.name`. | `42` | ![Development](https://img.shields.io/badge/-development-blue) |
-| <a id="code-namespace" href="#code-namespace">`code.namespace`</a> | string | The "namespace" within which `code.function.name` is defined. Usually the qualified class or module name, such that `code.namespace` + some separator + `code.function.name` form a unique identifier for the code unit. | `com.example.MyHttpService` | ![Development](https://img.shields.io/badge/-development-blue) |
 | <a id="code-stacktrace" href="#code-stacktrace">`code.stacktrace`</a> | string | A stacktrace as a string in the natural representation for the language runtime. The representation is to be determined and documented by each language SIG. | `at com.example.GenerateTrace.methodB(GenerateTrace.java:13)\n at com.example.GenerateTrace.methodA(GenerateTrace.java:9)\n at com.example.GenerateTrace.main(GenerateTrace.java:5)` | ![Development](https://img.shields.io/badge/-development-blue) |
 
+**[1] `code.function.name`:** Values and format depends on each language runtime, thus it is impossible to provide an exhaustive list of examples.
+The values are usually the same (or prefixes of) the ones found in native stack trace representation stored in
+`code.stacktrace` without information on arguments.
+
+Examples:
+
+* Java method: `com.example.MyHttpService.serveRequest`
+* Java anonymous class method: `com.mycompany.Main$1.myMethod`
+* Java lambda method: `com.mycompany.Main$$Lambda/0x0000748ae4149c00.myMethod`
+* PHP function: `GuzzleHttp\Client::transfer
+* Go function: `github.com/my/repo/pkg.foo.func5`
+* Elixir: `OpenTelemetry.Ctx.new`
+* Erlang: `opentelemetry_ctx:new`
+* Rust: `playground::my_module::my_cool_func`
+* C function: `fopen`
+
 ## Deprecated Code Attributes
 
 These deprecated attributes provide context about source code
 
 | Attribute | Type | Description | Examples | Stability |
 |---|---|---|---|---|
 | <a id="code-column" href="#code-column">`code.column`</a> | int | Deprecated, use `code.column.number` | `16` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Replaced by `code.column.number` |
-| <a id="code-filepath" href="#code-filepath">`code.filepath`</a> | string | Deprecated, use `code.file.path` instead | `/usr/local/MyApplication/content_root/app/index.php` | ![Development](https://img.shields.io/badge/-development-blue) |
+| <a id="code-filepath" href="#code-filepath">`code.filepath`</a> | string | Deprecated, use `code.file.path` instead | `/usr/local/MyApplication/content_root/app/index.php` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Replaced by `code.file.path` |
 | <a id="code-function" href="#code-function">`code.function`</a> | string | Deprecated, use `code.function.name` instead | `serveRequest` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Replaced by `code.function.name` |
 | <a id="code-lineno" href="#code-lineno">`code.lineno`</a> | int | Deprecated, use `code.line.number` instead | `42` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Replaced by `code.line.number` |
+| <a id="code-namespace" href="#code-namespace">`code.namespace`</a> | string | Deprecated, namespace is now included into `code.function.name` | `com.example.MyHttpService` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Value should be included in `code.function.name` which is expected to be a fully-qualified name. |

docs/general/attributes.md

@@ -431,12 +431,28 @@ about the span.
 | Attribute  | Type | Description  | Examples  | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability |
 |---|---|---|---|---|---|
 | [`code.column.number`](/docs/attributes-registry/code.md) | int | The column number in `code.file.path` best representing the operation. It SHOULD point within the code unit named in `code.function.name`. | `16` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
-| [`code.filepath`](/docs/attributes-registry/code.md) | string | Deprecated, use `code.file.path` instead | `/usr/local/MyApplication/content_root/app/index.php` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
-| [`code.function.name`](/docs/attributes-registry/code.md) | string | The method or function name, or equivalent (usually rightmost part of the code unit's name). | `serveRequest` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
+| [`code.filepath`](/docs/attributes-registry/code.md) | string | Deprecated, use `code.file.path` instead | `/usr/local/MyApplication/content_root/app/index.php` | `Recommended` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Replaced by `code.file.path` |
+| [`code.function.name`](/docs/attributes-registry/code.md) | string | The method or function fully-qualified name without arguments. The value should fit the natural representation of the language runtime, which is also likely the same used within `code.stacktrace` attribute value. [1] | `com.example.MyHttpService.serveRequest`; `GuzzleHttp\Client::transfer`; `fopen` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
 | [`code.line.number`](/docs/attributes-registry/code.md) | int | The line number in `code.file.path` best representing the operation. It SHOULD point within the code unit named in `code.function.name`. | `42` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
-| [`code.namespace`](/docs/attributes-registry/code.md) | string | The "namespace" within which `code.function.name` is defined. Usually the qualified class or module name, such that `code.namespace` + some separator + `code.function.name` form a unique identifier for the code unit. | `com.example.MyHttpService` | `Recommended` | ![Development](https://img.shields.io/badge/-development-blue) |
+| [`code.namespace`](/docs/attributes-registry/code.md) | string | Deprecated, namespace is now included into `code.function.name` | `com.example.MyHttpService` | `Recommended` | ![Deprecated](https://img.shields.io/badge/-deprecated-red)<br>Value should be included in `code.function.name` which is expected to be a fully-qualified name. |
 | [`code.stacktrace`](/docs/attributes-registry/code.md) | string | A stacktrace as a string in the natural representation for the language runtime. The representation is to be determined and documented by each language SIG. | `at com.example.GenerateTrace.methodB(GenerateTrace.java:13)\n at com.example.GenerateTrace.methodA(GenerateTrace.java:9)\n at com.example.GenerateTrace.main(GenerateTrace.java:5)` | `Opt-In` | ![Development](https://img.shields.io/badge/-development-blue) |
 
+**[1] `code.function.name`:** Values and format depends on each language runtime, thus it is impossible to provide an exhaustive list of examples.
+The values are usually the same (or prefixes of) the ones found in native stack trace representation stored in
+`code.stacktrace` without information on arguments.
+
+Examples:
+
+* Java method: `com.example.MyHttpService.serveRequest`
+* Java anonymous class method: `com.mycompany.Main$1.myMethod`
+* Java lambda method: `com.mycompany.Main$$Lambda/0x0000748ae4149c00.myMethod`
+* PHP function: `GuzzleHttp\Client::transfer
+* Go function: `github.com/my/repo/pkg.foo.func5`
+* Elixir: `OpenTelemetry.Ctx.new`
+* Erlang: `opentelemetry_ctx:new`
+* Rust: `playground::my_module::my_cool_func`
+* C function: `fopen`
+
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model/code/registry-deprecated.yaml

@@ -15,6 +15,7 @@ groups:
       - id: code.filepath
         type: string
         stability: development
+        deprecated: Replaced by `code.file.path`
         brief: >
           Deprecated, use `code.file.path` instead
         examples: /usr/local/MyApplication/content_root/app/index.php
@@ -32,3 +33,10 @@ groups:
         brief: >
           Deprecated, use `code.column.number`
         examples: 16
+      - id: code.namespace
+        type: string
+        stability: development
+        deprecated: Value should be included in `code.function.name` which is expected to be a fully-qualified name.
+        brief: >
+          Deprecated, namespace is now included into `code.function.name`
+        examples: com.example.MyHttpService

model/code/registry.yaml

@@ -9,15 +9,28 @@ groups:
         type: string
         stability: development
         brief: >
-          The method or function name, or equivalent (usually rightmost part of the code unit's name).
-        examples: serveRequest
-      - id: code.namespace
-        type: string
-        stability: development
-        brief: >
-          The "namespace" within which `code.function.name` is defined. Usually the qualified class or module name,
-          such that `code.namespace` + some separator + `code.function.name` form a unique identifier for the code unit.
-        examples: com.example.MyHttpService
+          The method or function fully-qualified name without arguments. The value should fit the natural representation of the language
+          runtime, which is also likely the same used within `code.stacktrace` attribute value.
+        examples:
+          - 'com.example.MyHttpService.serveRequest'
+          - 'GuzzleHttp\Client::transfer'
+          - 'fopen'
+        note: |
+          Values and format depends on each language runtime, thus it is impossible to provide an exhaustive list of examples.
+          The values are usually the same (or prefixes of) the ones found in native stack trace representation stored in
+          `code.stacktrace` without information on arguments.
+
+          Examples:
+
+          * Java method: `com.example.MyHttpService.serveRequest`
+          * Java anonymous class method: `com.mycompany.Main$1.myMethod`
+          * Java lambda method: `com.mycompany.Main$$Lambda/0x0000748ae4149c00.myMethod`
+          * PHP function: `GuzzleHttp\Client::transfer
+          * Go function: `github.com/my/repo/pkg.foo.func5`
+          * Elixir: `OpenTelemetry.Ctx.new`
+          * Erlang: `opentelemetry_ctx:new`
+          * Rust: `playground::my_module::my_cool_func`
+          * C function: `fopen`
       - id: code.file.path
         type: string
         stability: development