From 2136eb4f057a11b40899d03c6f20b7b586ef22f1 Mon Sep 17 00:00:00 2001
From: Ida Liu <119438987+ida613@users.noreply.github.com>
Date: Wed, 6 Nov 2024 10:36:06 -0500
Subject: [PATCH] simplify baggage code and add test case (#4858)

---
 .../src/opentracing/propagation/text_map.js   | 25 +++++++------------
 .../opentracing/propagation/text_map.spec.js  |  5 ++--
 2 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/packages/dd-trace/src/opentracing/propagation/text_map.js b/packages/dd-trace/src/opentracing/propagation/text_map.js
index 57a16325690..4c67cfa5957 100644
--- a/packages/dd-trace/src/opentracing/propagation/text_map.js
+++ b/packages/dd-trace/src/opentracing/propagation/text_map.js
@@ -123,26 +123,19 @@ class TextMapPropagator {
       })
     }
     if (this._hasPropagationStyle('inject', 'baggage')) {
-      if (this._config.baggageMaxItems < 1) return
       let baggage = ''
-      let counter = 1
+      let itemCounter = 0
+      let byteCounter = 0
+
       for (const [key, value] of Object.entries(spanContext._baggageItems)) {
-        baggage += `${this._encodeOtelBaggageKey(String(key).trim())}=${encodeURIComponent(String(value).trim())},`
-        if (counter === this._config.baggageMaxItems || counter > this._config.baggageMaxItems) break
-        counter += 1
+        const item = `${this._encodeOtelBaggageKey(String(key).trim())}=${encodeURIComponent(String(value).trim())},`
+        itemCounter += 1
+        byteCounter += item.length
+        if (itemCounter > this._config.baggageMaxItems || byteCounter > this._config.baggageMaxBytes) break
+        baggage += item
       }
+
       baggage = baggage.slice(0, baggage.length - 1)
-      let buf = Buffer.from(baggage)
-      if (buf.length > this._config.baggageMaxBytes) {
-        const originalBaggages = baggage.split(',')
-        buf = buf.subarray(0, this._config.baggageMaxBytes)
-        const truncatedBaggages = buf.toString('utf8').split(',')
-        const lastPairIndex = truncatedBaggages.length - 1
-        if (truncatedBaggages[lastPairIndex] !== originalBaggages[lastPairIndex]) {
-          truncatedBaggages.splice(lastPairIndex, 1)
-        }
-        baggage = truncatedBaggages.slice(0, this._config.baggageMaxItems).join(',')
-      }
       if (baggage) carrier.baggage = baggage
     }
   }
diff --git a/packages/dd-trace/test/opentracing/propagation/text_map.spec.js b/packages/dd-trace/test/opentracing/propagation/text_map.spec.js
index 4b2c85e55e5..45ddc905ee4 100644
--- a/packages/dd-trace/test/opentracing/propagation/text_map.spec.js
+++ b/packages/dd-trace/test/opentracing/propagation/text_map.spec.js
@@ -103,12 +103,13 @@ describe('TextMapPropagator', () => {
     it('should handle special characters in baggage', () => {
       const carrier = {}
       const baggageItems = {
-        '",;\\()/:<=>?@[]{}': '",;\\'
+        '",;\\()/:<=>?@[]{}🐶é我': '",;\\🐶é我'
       }
       const spanContext = createContext({ baggageItems })
 
       propagator.inject(spanContext, carrier)
-      expect(carrier.baggage).to.be.equal('%22%2C%3B%5C%28%29%2F%3A%3C%3D%3E%3F%40%5B%5D%7B%7D=%22%2C%3B%5C')
+      // eslint-disable-next-line max-len
+      expect(carrier.baggage).to.be.equal('%22%2C%3B%5C%28%29%2F%3A%3C%3D%3E%3F%40%5B%5D%7B%7D%F0%9F%90%B6%C3%A9%E6%88%91=%22%2C%3B%5C%F0%9F%90%B6%C3%A9%E6%88%91')
     })
 
     it('should drop excess baggage items when there are too many pairs', () => {