# HTTP semantic conventions declared stable LLMS index: [llms.txt](/llms.txt) --- Early this year, we launched an effort to stabilize HTTP semantic conventions. Today, we proudly announce that the HTTP semantic conventions are the _first_ OpenTelemetry semantic conventions to be declared **[stable](/docs/specs/otel/document-status/)**! This inaugural stable [v1.23.0](https://github.com/open-telemetry/semantic-conventions/releases/tag/v1.23.0) release marks a substantial advancement from earlier versions, featuring: - Enhancements resulting from [convergence with the Elastic Common Schema](/blog/2023/ecs-otel-semconv-convergence/), such as: - The `url.*` namespace, which can be reused in the future by non-HTTP semantic conventions - Replacing the `net.peer.*` and `net.host.*` namespaces with `client.*` and `server.*`, which - Works better for logs, where there's no span kind to indicate which side is peer and which side is host - Simplifies correlation across client and server telemetry (e.g. since you can join directly on `server.address` instead of joining where `net.peer.addr` == `net.host.addr`) - Provides a clean separation from the `network.*` namespace which is now only for low-level network attributes - More consistency around using the `http.request.*` and `http.response.*` namespaces - Improved consistency with Prometheus through standardization on seconds for metric units. - Streamlined attribute capture by omitting less useful attributes, reducing telemetry capture, processing, and storage costs. - Clarified the definition of default values, eliminating ambiguities when attributes are absent. - HTTP metrics are no longer vulnerable to cardinality explosion - `http.request.method` is limited to a (configurable) set of known methods - `server.address` and `server.port`, which are influenced by the `Host` header, are now Opt-In on HTTP metrics ## Migration plan Due to the significant number of modifications and the extensive user base affected by them, we require existing HTTP instrumentations published by OpenTelemetry to implement a migration plan that will assist users in transitioning to stable HTTP semantic conventions. We intend to use a similar strategy when stabilizing other semantic conventions. Specifically, when existing HTTP instrumentations published by OpenTelemetry are updated to the stable HTTP semantic conventions, they: - Need to introduce an environment variable `OTEL_SEMCONV_STABILITY_OPT_IN` in their existing major version, which accepts: - `http` - emit the stable HTTP and networking conventions, and stop emitting the old HTTP and networking conventions that the instrumentation emitted previously. - `http/dup` - emit both the old and the stable HTTP and networking conventions, allowing for a phased rollout of the stable semantic conventions. - The default behavior (in the absence of one of these values) is to continue emitting whatever version of the old HTTP and networking conventions the instrumentation was emitting previously. - Need to maintain (security patching at a minimum) their existing major version for at least six months after it starts emitting both sets of conventions. - May drop the environment variable in their next major version and emit only the stable HTTP and networking conventions. ## Summary of changes In this section, we summarize the changes made to the HTTP semantic conventions from [v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/trace/semantic_conventions/http.md) to [v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/). ### Common attributes across HTTP client and server spans | Change | Comments | | --- | --- | | `http.method` → `http.request.method` | Now captures only 9 common HTTP methods by default (configurable) plus `_OTHER` | | `http.status_code` → `http.response.status_code` | | | `http.request.header.` | • Dash (`"-"`) to underscore (`"_"`) normalization in `` has been removed
• On HTTP server spans: now must be provided to sampler | | `http.response.header.` | Dash (`"-"`) to underscore (`"_"`) normalization in `` has been removed | | `http.request_content_length` → `http.request.body.size` | • Recommended → Opt-In
• _Not marked stable yet_ | | `http.response_content_length` → `http.response.body.size` | • Recommended → Opt-In
• _Not marked stable yet_ | | `user_agent.original` | • On HTTP client spans: Recommended → Opt-In
• On HTTP server spans: now must be provided to sampler
• See note if [migrating from <= v1.18.0](#migrating-from--v1180) | | `net.protocol.name` → `network.protocol.name` | Recommended → Conditionally required if not `http` and `network.protocol.version` is set | | `net.protocol.version` → `network.protocol.version` | • Examples fixed: `2.0` → `2` and `3.0` → `3`
• See note if [migrating from <= v1.19.0](#migrating-from--v1190) | | `net.sock.family` | Removed | | `net.sock.peer.addr` → `network.peer.address` | On HTTP server spans: if `http.client_ip` was unknown, then also `net.sock.peer.addr` → `client.address`; `client.address` must be provided to sampler | | `net.sock.peer.port` → `network.peer.port` | Now captured even if same as `server.port` | | `net.sock.peer.name` | Removed | | New: `http.request.method_original` | Only captured when `http.request.method` is `_OTHER` | | New: `error.type` | New | References: - [Common attributes v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/trace/semantic_conventions/http.md#common-attributes) - [Common attributes v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/http-spans.md#common-attributes) ### HTTP client span attributes | Change | Comments | | --- | --- | | `http.url` → `url.full` | | | `http.resend_count` → `http.request.resend_count` | | | `net.peer.name` → `server.address` | | | `net.peer.port` → `server.port` | Now captured even when same as default port for scheme | References: - [HTTP client span attributes v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/trace/semantic_conventions/http.md#http-client) - [HTTP client span attributes v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/http-spans.md#http-client) ### HTTP server span attributes | Change | Comments | | --- | --- | | `http.route` | No change | | `http.target` → `url.path` and `url.query` | Split into two separate attributes | | `http.scheme` → `url.scheme` | Now factors in [X-Forwarded-Proto][], [Forwarded#proto][] headers | | `http.client_ip` → `client.address` | If `http.client_ip` was unknown (i.e., no [X-Forwarded-For][], [Forwarded#for][] headers), then `net.sock.peer.addr` → `client.address`; now must be provided to sampler | | `net.host.name` → `server.address` | Now based only on [Host][Host header], [:authority][HTTP/2 authority], [X-Forwarded-Host][], [Forwarded#host][] headers | | `net.host.port` → `server.port` | Now based only on [Host][Host header], [:authority][HTTP/2 authority], [X-Forwarded-Host][X-Forwarded-Host], [Forwarded#host][] headers | {.ot-table-first-col-50} References: - [HTTP server span attributes v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/trace/semantic_conventions/http.md#http-server) - [HTTP server span attributes v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/http-spans.md#http-server) ### HTTP client and server span names The `{http.method}` portion of span names is replace by `HTTP` when `{http.method}` is `_OTHER`. See note if [migrating from `<= v1.17.0`](#migrating-from--v1170). References: - [HTTP client and server span names v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/trace/semantic_conventions/http.md#name) - [HTTP client and server span names v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/http-spans.md#name) ### HTTP client duration metric Metric changes: - **Name**: `http.client.duration` → `http.client.request.duration` - **Unit**: `ms` → `s` - **Description**: `Measures the duration of inbound HTTP requests.` → `Duration of HTTP server requests.` - **Histogram buckets**: boundaries updated to reflect change from milliseconds to seconds, and zero bucket boundary removed - **Attributes**: see table below | Attribute change | Comments | | --- | --- | | `http.method` → `http.request.method` | Now captures only 9 common HTTP methods by default plus `_OTHER` | | `http.status_code` → `http.response.status_code` | | | `net.peer.name` → `server.address` | | | `net.peer.port` → `server.port` | Now captured even when same as default port for scheme | | `net.sock.peer.addr` | Removed | | `net.protocol.name` → `network.protocol.name` | Recommended → Conditionally required if not `http` and `network.protocol.version` is set | | `net.protocol.version` → `network.protocol.version` | Examples fixed: `2.0` → `2` and `3.0` → `3`; see note if [migrating from `<= v1.19.0`](#migrating-from--v1190) | | New: `error.type` | New | References: - [Metric `http.client.duration` v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/metrics/semantic_conventions/http-metrics.md#metric-httpclientduration) - [Metric `http.client.request.duration` v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.23.0/docs/http/http-metrics.md#metric-httpclientrequestduration) ### HTTP server duration metric Metric changes: - **Name**: `http.server.duration` → `http.server.request.duration` - **Unit**: `ms` → `s` - **Description**: `Measures the duration of inbound HTTP requests.` → `Duration of HTTP server requests.` - **Histogram buckets**: boundaries updated to reflect change from milliseconds to seconds, and zero bucket boundary removed - **Attributes**: see table below | Attribute change | Comments | | --- | --- | | `http.route` | No change | | `http.method` → `http.request.method` | Now captures only 9 common HTTP methods by default plus `_OTHER` | | `http.status_code` → `http.response.status_code` | | | `http.scheme` → `url.scheme` | Now factors in [`X-Forwarded-Proto` span][X-Forwarded-Proto], [`Forwarded#proto` span][Forwarded#proto] headers | | `net.protocol.name` → `network.protocol.name` | Recommended → Conditionally required if not `http` and `network.protocol.version` is set | | `net.protocol.version` → `network.protocol.version` | Examples fixed: `2.0` → `2` and `3.0` → `3`; see note if [migrating from `<= v1.19.0`](#migrating-from--v1190) | | `net.host.name` → `server.address` | • Recommended → Opt-In (due to high-cardinality vulnerability since based on HTTP headers)
• Now based only on [`Host` span][Host header], [`:authority` span][HTTP/2 authority], [`X-Forwarded-Host` span][X-Forwarded-Host], [`Forwarded#host` span][Forwarded#host] headers | | `net.host.port` → `server.port` | • Recommended → Opt-In (due to high-cardinality vulnerability since based on HTTP headers)
• Now based only on [`Host` span][Host header], [`:authority` span][HTTP/2 authority], [`X-Forwarded-Host` span][X-Forwarded-Host], [`Forwarded#host` span][Forwarded#host] headers | | New: `error.type` | New | {.ot-table-first-col-50} References: - [Metric `http.server.duration` v1.20.0](https://github.com/open-telemetry/opentelemetry-specification/blob/v1.20.0/specification/metrics/semantic_conventions/http-metrics.md#metric-httpserverduration) - [Metric `http.server.request.duration` v1.23.0 (stable)](https://github.com/open-telemetry/semantic-conventions/blob/v1.22.0/docs/http/http-metrics.md#metric-httpserverrequestduration) ## Migrating from a version earlier than v1.20.0? ### Migrating from `<= v1.19.0` - `http.flavor` → `network.protocol.version` - Examples fixed: `2.0` → `2` and `3.0` → `3` ### Migrating from `<= v1.18.0` - `http.user_agent` → `user_agent.original` ### Migrating from `<= v1.17.0` #### HTTP server span name - When `http.route` is available:
`{http.route}` → `{summary} {http.route}` - When `http.route` is not available:
`HTTP {http.method}` → `{summary}` Where `{summary}` is `{http.method}`, unless `{http.method}` is `_OTHER`, in which case `{summary}` is `HTTP`. #### HTTP client span name - `HTTP {http.method}` → `{summary}` Where `{summary}` is `{http.method}`, unless `{http.method}` is `_OTHER`, in which case `{summary}` is `HTTP`. [Host header]: https://tools.ietf.org/html/rfc7230#section-5.4 [HTTP/2 authority]: https://tools.ietf.org/html/rfc9113#section-8.3.1 [Forwarded#for]: https://developer.mozilla.org/docs/Web/HTTP/Headers/Forwarded#for [Forwarded#proto]: https://developer.mozilla.org/docs/Web/HTTP/Headers/Forwarded#proto [Forwarded#host]: https://developer.mozilla.org/docs/Web/HTTP/Headers/Forwarded#host [X-Forwarded-For]: https://developer.mozilla.org/docs/Web/HTTP/Headers/X-Forwarded-For [X-Forwarded-Proto]: https://developer.mozilla.org/docs/Web/HTTP/Headers/X-Forwarded-Proto [X-Forwarded-Host]: https://developer.mozilla.org/docs/Web/HTTP/Headers/X-Forwarded-Host ## Community Kudos This was a massive community effort: thanks to all who got involved! A special thanks to [Liudmila Molkova](https://github.com/lmolkova) for sharing her HTTP domain expertise, which helped drive this effort every step of the way.