[new] OpenTelemetry handler: support spans created outside Telemere

BEFORE this commit: Telemere captured OpenTelemetry context only when generating tracing signals (`trace!`, `spy!`, etc.). AFTER this commit: Telemere always captures OpenTelemetry context when present. Motivation for the change: Telemere users may have spans automatically created by the OpenTelemetry Java Agent, or manually created by other libs like clj-otel. By always capturing the OpenTelemetry context when present, this lets even non-tracing Telemere signals (like `log!`) include the relevant trace and span IDs for external tooling. Thanks to @devurandom for suggesting this, and for helping debug/identify the necessary changes 🙏
[fix] OpenTelemetry handler: add missing line info to output
2026-02-22 18:19:09 +00:00 · 2025-12-05 08:03:41 +01:00 · 2025-12-04 21:13:41 +01:00 · 2025-12-04 21:13:41 +01:00 · 2025-12-04 21:13:37 +01:00
4 changed files with 72 additions and 64 deletions
--- a/main/src/taoensso/telemere/impl.cljc
+++ b/main/src/taoensso/telemere/impl.cljc
@ -38,7 +38,10 @@
     (def enabled:otel-tracing?
       "Documented at `taoensso.telemere/otel-tracing?`."
       (enc/get-env {:as :bool, :default present:otel?}
-         :taoensso.telemere/otel-tracing<.platform>))))
+         :taoensso.telemere/otel-tracing<.platform>))
+
+     (def enabled:incl-host-info?   "Include `:host` info in signals by default?"   (enc/get-env {:as :bool, :default true} :taoensso.telemere/incl-host-info))
+     (def enabled:incl-thread-info? "Include `:thread` info in signals by default?" (enc/get-env {:as :bool, :default true} :taoensso.telemere/incl-thread-info))))

 (def uid-kind
  "Documented at `taoensso.telemere/*uid-fn*`."
@ -573,9 +576,9 @@
                    (str "Signal needs compile-time `:trace?` value at "
                      (sigs/format-callsite ns-form coords))))

-                host-form   (auto-> (get opts :host   :auto) (when clj? `(enc/host-info)))
-                thread-form (auto-> (get opts :thread :auto) (when clj? `(enc/thread-info)))
-                inst-form   (auto-> (get opts :inst   :auto)            `(enc/now-inst*))
+                host-form   (auto-> (get opts :host   :auto) (when (and clj? enabled:incl-host-info?)   `(enc/host-info)))
+                thread-form (auto-> (get opts :thread :auto) (when (and clj? enabled:incl-thread-info?) `(enc/thread-info)))
+                inst-form   (auto-> (get opts :inst   :auto) `(enc/now-inst*))

                parent-form (get opts :parent `*trace-parent*)
                root-form0  (get opts :root   `*trace-root*)
@ -609,7 +612,7 @@
                              (dissoc opts
                                :elidable? :coords :inst :uid :xfn :xfn+ :kvs+,
                                :sample :ns :kind :id :level :filter :when #_:limit #_:limit-by,
-                                :ctx :ctx+ :parent #_:trace?, :do :let :data :msg :error,
+                                :ctx :ctx+ :parent :trace?, :do :let :data :msg :error,
                                :run :run-form :run-val, :elide? :allow? #_:callsite-id,
                                :host :thread :otel/context))]

@ -635,10 +638,10 @@
                      (let [record-form
                            (let   [clause [(if run-form? :run :no-run) (if clj? :clj :cljs)]]
                              (case clause
-                                [:run    :clj ]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords ~host-form ~'__thread ~'__otel-context1, ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~'_msg_,   ~'_run-err  '~show-run-form ~show-run-val ~'_end-inst ~'_run-nsecs)
-                                [:run    :cljs]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords                                          ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~'_msg_,   ~'_run-err  '~show-run-form ~show-run-val ~'_end-inst ~'_run-nsecs)
-                                [:no-run :clj ]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords ~host-form ~'__thread ~'__otel-context1, ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~msg-form, ~error-form nil             nil           nil         nil)
-                                [:no-run :cljs]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords                                          ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~msg-form, ~error-form nil             nil           nil         nil)
+                                [:run    :clj ]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords ~host-form ~'__thread ~'__otel-context, ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~'_msg_,   ~'_run-err  '~show-run-form ~show-run-val ~'_end-inst ~'_run-nsecs)
+                                [:run    :cljs]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords                                         ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~'_msg_,   ~'_run-err  '~show-run-form ~show-run-val ~'_end-inst ~'_run-nsecs)
+                                [:no-run :clj ]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords ~host-form ~'__thread ~'__otel-context, ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~msg-form, ~error-form nil             nil           nil         nil)
+                                [:no-run :cljs]  `(Signal. 1 ~'__inst ~'__uid, ~'__ns ~coords                                         ~sample-form, ~'__kind ~'__id ~'__level, ~ctx-form ~parent-form ~'__root1, ~data-form ~kvs-form ~msg-form, ~error-form nil             nil           nil         nil)
                                (truss/ex-info!
                                  (str "Unexpected signal constructor args at "
                                    (sigs/format-callsite ns-form coords)))))
@ -679,12 +682,26 @@
                run-fn-form (when run-form? `(fn [] ~run-form))
                run-form*   (when run-form? `(~'__run-fn-form))

-                into-let-form
+                binds-form-base
+                `[~'__inst   ~inst-form
+                  ~'__thread ~thread-form
+                  ~'__root0  ~root-form0 ; ?{:keys [id uid]}
+
+                  ~'__otel-context
+                  ~(when (and clj? enabled:otel-tracing?)
+                     (if run-form?
+                       `(otel-context+span ~'__id ~'__inst ~(get opts :otel/context `(otel-context)) ~(get opts :otel/span-kind))
+                       (do                                  (get opts :otel/context `(otel-context)))))
+
+                  ~'__uid
+                  ~(if (and clj? enabled:otel-tracing? trace?)
+                     (auto-> uid-form `(or (otel-span-id ~'__otel-context) (com.taoensso.encore.Ids/genHexId16)))
+                     (auto-> uid-form `(taoensso.telemere/*uid-fn* (if ~'__root0 false true))))]
+
+                binds-form-more
                (enc/cond!
-                  (not trace?) ; Don't trace
-                  `[~'__otel-context1 nil
-                    ~'__uid   ~(auto-> uid-form `(taoensso.telemere/*uid-fn* (if ~'__root0 false true)))
-                    ~'__root1 ~'__root0 ; Retain, but don't establish
+                  (not trace?) ; Non-tracing signal
+                  `[~'__root1 ~'__root0 ; Retain, but don't establish
                    ~'__run-result
                    ~(when run-form?
                       `(let [t0# (enc/now-nano*)]
@ -694,9 +711,7 @@

                  ;; Trace without OpenTelemetry
                  (or cljs? (not enabled:otel-tracing?))
-                  `[~'__otel-context1 nil
-                    ~'__uid  ~(auto-> uid-form `(taoensso.telemere/*uid-fn* (if ~'__root0 false true)))
-                    ~'__root1 (or ~'__root0 ~(when trace? `{:id ~'__id, :uid ~'__uid}))
+                  `[~'__root1 (or ~'__root0 ~(when trace? `{:id ~'__id, :uid ~'__uid}))
                    ~'__run-result
                    ~(when run-form?
                       `(binding [*trace-root*   ~'__root1
@ -708,20 +723,17 @@

                  ;; Trace with OpenTelemetry
                  (and clj? enabled:otel-tracing?)
-                  `[~'__otel-context0  ~(get opts :otel/context `(otel-context)) ; Context
-                    ~'__otel-context1  ~(if run-form? `(otel-context+span ~'__id ~'__inst ~'__otel-context0 ~(get opts :otel/span-kind)) ~'__otel-context0)
-                    ~'__uid            ~(auto-> uid-form `(or (otel-span-id ~'__otel-context1) (com.taoensso.encore.Ids/genHexId16)))
-                    ~'__root1
+                  `[~'__root1
                    (or ~'__root0
                      ~(when trace?
-                         `{:id ~'__id, :uid (or (otel-trace-id ~'__otel-context1) (com.taoensso.encore.Ids/genHexId32))}))
+                         `{:id ~'__id, :uid (or (otel-trace-id ~'__otel-context) (com.taoensso.encore.Ids/genHexId32))}))

                    ~'__run-result
                    ~(when run-form?
-                       `(binding [*otel-context* ~'__otel-context1
+                       `(binding [*otel-context* ~'__otel-context
                                  *trace-root*   ~'__root1
                                  *trace-parent* {:id ~'__id, :uid ~'__uid}]
-                          (let [otel-scope# (.makeCurrent ~'__otel-context1)
+                          (let [otel-scope# (.makeCurrent ~'__otel-context)
                                t0#         (enc/now-nano*)]
                            (truss/try*
                              (do            (RunResult. ~run-form* nil (- (enc/now-nano*) t0#)))
@ -738,11 +750,8 @@

                  (enc/if-not ~allow?
                    ~run-form*
-                    (let [~'__inst   ~inst-form
-                          ~'__thread ~thread-form
-                          ~'__root0  ~root-form0 ; ?{:keys [id uid]}
-
-                          ~@into-let-form ; Inject conditional bindings
+                    (let [~@binds-form-base
+                          ~@binds-form-more
                          signal# ~signal-delay-form]

                      (dispatch-signal!
--- a/main/src/taoensso/telemere/open_telemetry.clj
+++ b/main/src/taoensso/telemere/open_telemetry.clj
@ -219,15 +219,15 @@

      (if (or common-attrs trace-attrs)
        (let [ab (Attributes/builder)]
-          (when-let [ns   (get signal :ns)]    (.put ab "ns"   (str  ns)))
-          (when-let [line (get signal :line)]  (.put ab "line" (long line)))
+          (when-let [ns   (get         signal :ns)]         (.put ab "ns"   (str  ns)))
+          (when-let [line (enc/get-in* signal [:coords 0])] (.put ab "line" (long line)))
          (when-let [attrs common-attrs] (put-attrs! ab attrs))
          (when-let [attrs  trace-attrs] (put-attrs! ab attrs))
          (.build ab))

        ;; Common case
-        (when-let [ns   (get signal :ns)]
-          (if-let [line (get signal :line)]
+        (when-let [ns   (get         signal :ns)]
+          (if-let [line (enc/get-in* signal [:coords 0])]
            (Attributes/of ak-ns ns, ak-line (long line))
            (Attributes/of ak-ns ns)))))))

--- a/main/test/taoensso/telemere_tests.cljc
+++ b/main/test/taoensso/telemere_tests.cljc
@ -727,7 +727,7 @@
               (is (sm? (with-sig (-> (.atWarn sl) (.log "Hello"))) {:level :warn, :ns "my.class", :kind :slf4j, :msg_ "Hello", :inst enc/inst?}) "Fluent API: warn basics")])

            (testing "Message formatting"
-             (let [msgp "x={},y={}", expected {:msg_ "x=1,y=2", :data {:slf4j/args ["1" "2"]}}]
+             (let [msgp "x={},y={}", expected {:msg_ "x=1,y=2", :slf4j/args (fn [objs] (= (vec objs) ["1" "2"]))}]
               [(is (sm? (with-sig (.info sl msgp "1" "2"))                                                           expected) "Legacy API: formatted message, raw args")
                (is (sm? (with-sig (-> (.atInfo sl) (.setMessage msgp) (.addArgument "1") (.addArgument "2") (.log))) expected) "Fluent API: formatted message, raw args")]))

@ -738,8 +738,8 @@
                    m2 (#'slf4j/est-marker! "M2")
                    cm (#'slf4j/est-marker! "Compound" "M1" "M2")]

-                [(is (sm? (with-sig (.info sl cm "Hello"))                                    {:data {:slf4j/marker-names #{"Compound" "M1" "M2"}}}) "Legacy API: markers")
-                 (is (sm? (with-sig (-> (.atInfo sl) (.addMarker m1) (.addMarker cm) (.log))) {:data {:slf4j/marker-names #{"Compound" "M1" "M2"}}}) "Fluent API: markers")]))
+                [(is (sm? (with-sig (.info sl cm "Hello"))                                    {:slf4j/markers #{"Compound" "M1" "M2"}}) "Legacy API: markers")
+                 (is (sm? (with-sig (-> (.atInfo sl) (.addMarker m1) (.addMarker cm) (.log))) {:slf4j/markers #{"Compound" "M1" "M2"}}) "Fluent API: markers")]))

            (testing "Errors"
              [(is (sm? (with-sig (.warn sl "An error" ^Throwable ex1))     {:level :warn, :error ex1}) "Legacy API: errors")
--- a/slf4j/src/taoensso/telemere/slf4j.clj
+++ b/slf4j/src/taoensso/telemere/slf4j.clj
@ -63,13 +63,13 @@

 (comment [(est-marker! "a1" "a2") (get-marker  "a1") (= (get-marker "a1") (get-marker "a1"))])

-(def ^:private marker-names
+(def ^:private get-marker-names
  "Returns #{<MarkerName>}. Cached => assumes markers NOT modified after creation."
  ;; We use `BasicMarkerFactory` so:
  ;;   1. Our markers are just labels (no other content besides their name).
  ;;   2. Markers with the same name are identical (enabling caching).
  (enc/fmemoize
-    (fn marker-names [marker-or-markers]
+    (fn get-marker-names             [marker-or-markers]
      (if (instance? org.slf4j.Marker marker-or-markers)

        ;; Single marker
@ -79,15 +79,15 @@
          (if-not (.hasReferences m)
            acc
            (enc/reduce-iterator!
-              (fn [acc  ^org.slf4j.Marker in]
-                (if-not   (.hasReferences in)
-                  (conj acc (.getName     in))
-                  (into acc (marker-names in))))
+              (fn [acc      ^org.slf4j.Marker in]
+                (if-not   (.hasReferences     in)
+                  (conj acc (.getName         in))
+                  (into acc (get-marker-names in))))
              acc (.iterator m))))

        ;; Vector of markers
        (reduce
-          (fn [acc in] (into acc (marker-names in)))
+          (fn [acc in] (into acc (get-marker-names in)))
          #{} (truss/have vector? marker-or-markers))))))

 (comment
@ -97,9 +97,9 @@
        ms [m1 m2]]

    (enc/qb 1e6 ; [45.52 47.48 44.85]
-      (marker-names m1)
-      (marker-names cm)
-      (marker-names ms))))
+      (get-marker-names m1)
+      (get-marker-names cm)
+      (get-marker-names ms))))

 ;;;; Interop fns (called by `TelemereLogger`)

@ -132,11 +132,10 @@
       (org.slf4j.helpers.MessageFormatter/basicArrayFormat
         msg-pattern args))

-     :data
-     (enc/assoc-some nil
-       :slf4j/marker-names marker-names
-       :slf4j/args (when args (vec args))
-       :slf4j/kvs  kvs)})
+     :slf4j/args    args ; Object[]
+     :slf4j/markers marker-names ; Usu. used for routing, filtering, xfns, etc.
+     :data (when kvs {:slf4j/kvs kvs})})
+
  nil)

 (defn- log!
@ -144,24 +143,24 @@

  ;; Modern "fluent" API calls
  ([logger-name ^org.slf4j.event.LoggingEvent event]
-   (let [inst        (or (when-let [ts (.getTimeStamp event)] (java.time.Instant/ofEpochMilli ts)) (enc/now-inst*))
-         level       (.getLevel     event)
-         error       (.getThrowable event)
-         msg-pattern (.getMessage   event)
-         args        (when-let [args    (.getArgumentArray event)] args)
-         markers     (when-let [markers (.getMarkers       event)] (marker-names (vec markers)))
-         kvs         (when-let [kvps    (.getKeyValuePairs event)]
-                       (reduce
-                         (fn [acc ^org.slf4j.event.KeyValuePair kvp]
-                           (assoc acc (.-key kvp) (.-value kvp)))
-                         nil kvps))]
+   (let [inst         (or (when-let [ts (.getTimeStamp event)] (java.time.Instant/ofEpochMilli ts)) (enc/now-inst*))
+         level        (.getLevel     event)
+         error        (.getThrowable event)
+         msg-pattern  (.getMessage   event)
+         args         (when-let [args    (.getArgumentArray event)] args)
+         marker-names (when-let [markers (.getMarkers       event)] (get-marker-names (vec markers)))
+         kvs          (when-let [kvps    (.getKeyValuePairs event)]
+                        (reduce
+                          (fn [acc ^org.slf4j.event.KeyValuePair kvp]
+                            (assoc acc (.-key kvp) (.-value kvp)))
+                          nil kvps))]

     (when-debug (println [:slf4j/fluent-log-call (sig-level level) logger-name]))
-     (normalized-log! logger-name level inst error msg-pattern args markers kvs)))
+     (normalized-log! logger-name level inst error msg-pattern args marker-names kvs)))

  ;; Legacy API calls
  ([logger-name ^org.slf4j.event.Level level error msg-pattern args marker]
-   (let [marker-names (when marker (marker-names marker))]
+   (let [marker-names (when marker (get-marker-names marker))]
     (when-debug (println [:slf4j/legacy-log-call (sig-level level) logger-name]))
     (normalized-log! logger-name level (enc/now-inst*) error msg-pattern args marker-names nil))))
Author	SHA1	Message	Date
Peter Taoussanis	a6fc4adf6a	[new] OpenTelemetry handler: support spans created outside Telemere Some checks failed Clj tests / tests (17, ubuntu-latest) (push) Has been cancelled Details Clj tests / tests (19, ubuntu-latest) (push) Has been cancelled Details Clj tests / tests (21, ubuntu-latest) (push) Has been cancelled Details Cljs tests / tests (21, ubuntu-latest) (push) Has been cancelled Details Graal tests / tests (17, macOS-latest) (push) Has been cancelled Details Graal tests / tests (17, ubuntu-latest) (push) Has been cancelled Details Graal tests / tests (17, windows-latest) (push) Has been cancelled Details BEFORE this commit: Telemere captured OpenTelemetry context only when generating tracing signals (`trace!`, `spy!`, etc.). AFTER this commit: Telemere always captures OpenTelemetry context when present. Motivation for the change: Telemere users may have spans automatically created by the OpenTelemetry Java Agent, or manually created by other libs like clj-otel. By always capturing the OpenTelemetry context when present, this lets even non-tracing Telemere signals (like `log!`) include the relevant trace and span IDs for external tooling. Thanks to @devurandom for suggesting this, and for helping debug/identify the necessary changes 🙏	2025-12-05 08:03:41 +01:00
Peter Taoussanis	6155713fde	[fix] OpenTelemetry handler: add missing line info to output Previous code was a vestigial leftover from when signals had {:line <num> :column <num> ...} rather than {:coords [<line-num> <column-num>] ...}	2025-12-04 21:13:41 +01:00
Peter Taoussanis	a883df3c41	[new] [#68 ] Add config to skip host and/or thread info	2025-12-04 21:13:41 +01:00
Peter Taoussanis	e6ce33dd4e	[mod] SLF4J->Telemere backend: move noisy stuff out of signal data This is a BREAKING change for the small minority of users that: 1. Are using the `taoensso.telemere.slf4j` backend, AND 2. Are using the low-level `:slf4j/args` or `:slf4j/marker-names` values in signal `:data` BEFORE this commit: SLF4J signals contain: {:data {:slf4j/kvs {...}, :slf4j/args [...], :slf4j/marker-names #{...}}, ...}. AFTER this commit: SLF4J signals contain: {:data {:slf4j/kvs {...}}, :kvs {:slf4j/args <Object[]>, :slf4j/markers #{...}}, ...} So: - [:data :slf4j/marker-names] has moved to [:kvs :slf4j/markers]. - [:data :slf4j/args] has moved to [:kvs :slf4j/args], and is now an Object[] rather than vector. Motivation for the change: The new behaviour is a more sensible default. Basically: anything in `:data` is included by default in output. But :slf4j/args are generally anyway already in the signal's formatted message, so this ends up just creating duplicate output. Likewise markers are generally used more for filtering/xfns than for output labelling, so excluding them from default output is sensible.	2025-12-04 21:13:37 +01:00