Use `HTTP` instead of `_OTHER` in HTTP span names (if method is unknown) (#270)

Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>
Co-authored-by: Joao Grassi <joao@joaograssi.com>
Co-authored-by: Christian Neumüller <christian+github@neumueller.me>
Co-authored-by: Armin Ruech <armin.ruech@dynatrace.com>

CHANGELOG.md

@@ -65,6 +65,8 @@ release.
   ([#276](https://github.com/open-telemetry/semantic-conventions/pull/276))
 - Add host cpu resource attributes.
   ([#209](https://github.com/open-telemetry/semantic-conventions/pull/209))
+- BREAKING: Change HTTP span name when method is unknown (use `HTTP` instead of `_OTHER`)
+  ([#270](https://github.com/open-telemetry/semantic-conventions/pull/270))
 - Moved RPC streaming notes from metric brief section to notes section.
   ([#275](https://github.com/open-telemetry/semantic-conventions/pull/275))
 

docs/http/http-spans.md

@@ -62,13 +62,23 @@ and various HTTP versions like 1.1, 2 and SPDY.
 ## Name
 
 HTTP spans MUST follow the overall [guidelines for span names](https://github.com/open-telemetry/opentelemetry-specification/tree/v1.22.0/specification/trace/api.md#span).
-HTTP server span names SHOULD be `{http.request.method} {http.route}` if there is a
-(low-cardinality) `http.route` available.
-HTTP server span names SHOULD be `{http.request.method}` if there is no (low-cardinality)
-`http.route` available.
+
+<!-- markdown-link-check-disable -->
+<!-- HTML anchors are not supported https://github.com/tcort/markdown-link-check/issues/225-->
+HTTP server span names SHOULD be `{method} {http.route}` if there is a
+(low-cardinality) `http.route` available (see below for the exact definition of the [`{method}`](#method-placeholder) placeholder).
+
+If there is no (low-cardinality) `http.route` available, HTTP server span names
+SHOULD be [`{method}`](#method-placeholder).
+
 HTTP client spans have no `http.route` attribute since client-side instrumentation
-is not generally aware of the "route", and therefore HTTP client spans SHOULD use
-`{http.request.method}`.
+is not generally aware of the "route", and therefore HTTP client spans SHOULD be
+[`{method}`](#method-placeholder).
+<!-- markdown-link-check-enable -->
+
+The <span id="method-placeholder">`{method}`</span> MUST be `{http.request.method}` if the method represents the original method known to the instrumentation.
+In other cases (when `{http.request.method}` is set to `_OTHER`), `{method}` MUST be `HTTP`.
+
 Instrumentation MUST NOT default to using URI
 path as span name, but MAY provide hooks to allow custom logic to override the
 default span name.

package.json

@@ -11,7 +11,7 @@
   "devDependencies": {
     "gulp": "^4.0.2",
     "js-yaml": "^4.1.0",
-    "markdown-link-check": "3.10.3",
+    "markdown-link-check": "^3.11.2",
     "markdown-toc": "^1.2.0",
     "markdownlint": "^0.29.0",
     "markdownlint-cli": "0.31.0",