Change http.request.body.size and http.response.body.size attributes from recommended to opt-in

CHANGELOG.md

@@ -30,6 +30,9 @@ release.
   ([#384](https://github.com/open-telemetry/semantic-conventions/pull/384))
 - BREAKING: Remove `total` from list of well-known values of `system.memory.state` attribute.
   ([#409](https://github.com/open-telemetry/semantic-conventions/pull/409))
+- Change `http.request.body.size` and `http.response.body.size`
+  from recommended to opt-in.
+  ([#460](https://github.com/open-telemetry/semantic-conventions/pull/460))
 
 ### Features
 

docs/attributes-registry/http.md

@@ -68,8 +68,8 @@ SHOULD include the [application root](/docs/http/http-spans.md#http-server-defin
 | Attribute  | Type | Description  | Examples  |
 |---|---|---|---|
 | `http.method` | string | Deprecated, use `http.request.method` instead. | `GET`; `POST`; `HEAD` |
-| `http.request_content_length` | int | Deprecated, use `http.request.body.size` instead. | `3495` |
-| `http.response_content_length` | int | Deprecated, use `http.response.body.size` instead. | `3495` |
+| `http.request_content_length` | int | Deprecated, use the opt-in `http.request.header.content-length` instead. | `3495` |
+| `http.response_content_length` | int | Deprecated, use the opt-in `http.response.header.content-length` instead. | `3495` |
 | `http.scheme` | string | Deprecated, use `url.scheme` instead. | `http`; `https` |
 | `http.status_code` | int | Deprecated, use `http.response.status_code` instead. | `200` |
 | `http.target` | string | Deprecated, use `url.path` and `url.query` instead. | `/search?q=OpenTelemetry#SemConv` |

docs/http/http-spans.md

@@ -119,11 +119,9 @@ sections below.
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
 | `error.type` | string | Describes a class of error the operation ended with. [1] | `timeout`; `java.net.UnknownHostException`; `server_certificate_invalid`; `500` | Conditionally Required: If request has ended with an error. |
-| [`http.request.body.size`](../attributes-registry/http.md) | int | The size of the request payload body in bytes. This is the number of bytes transferred excluding headers and is often, but not always, present as the [Content-Length](https://www.rfc-editor.org/rfc/rfc9110.html#field.content-length) header. For requests using transport encoding, this should be the compressed size. | `3495` | Recommended |
 | [`http.request.header.<key>`](../attributes-registry/http.md) | string[] | HTTP request headers, `<key>` being the normalized HTTP Header name (lowercase), the value being the header values. [2] | `http.request.header.content-type=["application/json"]`; `http.request.header.x-forwarded-for=["1.2.3.4", "1.2.3.5"]` | Opt-In |
 | [`http.request.method`](../attributes-registry/http.md) | string | HTTP request method. [3] | `GET`; `POST`; `HEAD` | Required |
 | [`http.request.method_original`](../attributes-registry/http.md) | string | Original HTTP method sent by the client in the request line. | `GeT`; `ACL`; `foo` | Conditionally Required: [4] |
-| [`http.response.body.size`](../attributes-registry/http.md) | int | The size of the response payload body in bytes. This is the number of bytes transferred excluding headers and is often, but not always, present as the [Content-Length](https://www.rfc-editor.org/rfc/rfc9110.html#field.content-length) header. For requests using transport encoding, this should be the compressed size. | `3495` | Recommended |
 | [`http.response.header.<key>`](../attributes-registry/http.md) | string[] | HTTP response headers, `<key>` being the normalized HTTP Header name (lowercase), the value being the header values. [5] | `http.response.header.content-type=["application/json"]`; `http.response.header.my-custom-header=["abc", "def"]` | Opt-In |
 | [`http.response.status_code`](../attributes-registry/http.md) | int | [HTTP response status code](https://tools.ietf.org/html/rfc7231#section-6). | `200` | Conditionally Required: If and only if one was received/sent. |
 | [`network.protocol.name`](../attributes-registry/network.md) | string | [OSI application layer](https://osi-model.com/application-layer/) or non-OSI equivalent. [6] | `http`; `spdy` | Opt-In |

model/registry/deprecated/http.yaml

@@ -31,11 +31,11 @@ groups:
         examples: ['/search?q=OpenTelemetry#SemConv']
       - id: request_content_length
         type: int
-        brief: 'Deprecated, use `http.request.body.size` instead.'
+        brief: 'Deprecated, use the opt-in `http.request.header.content-length` instead.'
         stability: deprecated
         examples: 3495
       - id: response_content_length
         type: int
-        brief: 'Deprecated, use `http.response.body.size` instead.'
+        brief: 'Deprecated, use the opt-in `http.response.header.content-length` instead.'
         stability: deprecated
         examples: 3495

model/registry/http.yaml

@@ -11,6 +11,7 @@
           is often, but not always, present as the [Content-Length](https://www.rfc-editor.org/rfc/rfc9110.html#field.content-length)
           header. For requests using transport encoding, this should be the compressed size.
         examples: 3495
+        stability: experimental # this should not be marked stable with other HTTP attributes
       - id: request.header
         type: template[string[]]
         brief: >
@@ -97,6 +98,7 @@
           is often, but not always, present as the [Content-Length](https://www.rfc-editor.org/rfc/rfc9110.html#field.content-length)
           header. For requests using transport encoding, this should be the compressed size.
         examples: 3495
+        stability: experimental # this should not be marked stable with other HTTP attributes
       - id: response.header
         type: template[string[]]
         brief: >

model/trace/http.yaml

@@ -10,10 +10,8 @@ groups:
       - ref: http.request.method_original
         requirement_level:
           conditionally_required: If and only if it's different than `http.request.method`.
-      - ref: http.request.body.size
       - ref: http.request.header
         requirement_level: opt_in
-      - ref: http.response.body.size
       - ref: http.response.header
         requirement_level: opt_in
       - ref: http.request.method