fix(shared): keep valid OTEL headers when one entry is malformed (#12260)

parseKeyPairsIntoRecord wrapped the whole forEach in one try/catch, so a single entry that broke decodeURIComponent (e.g. a stray % in OTEL_EXPORTER_OTLP_HEADERS) aborted the loop and silently dropped every remaining header. Move the try/catch inside the loop to skip only the malformed entry. Adds regression tests.

sdk/packages/shared/src/parse/headers/utils.test.ts

@@ -0,0 +1,49 @@
+import { describe, expect, it } from "vitest";
+import { parseKeyPairsIntoRecord } from "./utils";
+
+describe("parseKeyPairsIntoRecord", () => {
+	it("parses comma-separated key=value pairs", () => {
+		expect(parseKeyPairsIntoRecord("a=1,b=2,c=3")).toEqual({
+			a: "1",
+			b: "2",
+			c: "3",
+		});
+	});
+
+	it("returns an empty record for empty or undefined input", () => {
+		expect(parseKeyPairsIntoRecord("")).toEqual({});
+		expect(parseKeyPairsIntoRecord(undefined)).toEqual({});
+	});
+
+	it("trims whitespace and decodes percent-encoded keys and values", () => {
+		expect(parseKeyPairsIntoRecord(" Authorization = Bearer%20abc ")).toEqual({
+			Authorization: "Bearer abc",
+		});
+	});
+
+	it("skips entries without a separator or with an empty key", () => {
+		expect(parseKeyPairsIntoRecord("novalue,=nokey,good=1")).toEqual({
+			good: "1",
+		});
+	});
+
+	it("keeps well-formed entries when a later entry is malformed", () => {
+		// `b=%` is an invalid percent-encoding: decodeURIComponent throws on it.
+		// The malformed entry must be skipped without discarding `a` or `c`.
+		expect(parseKeyPairsIntoRecord("a=1,b=%,c=3")).toEqual({
+			a: "1",
+			c: "3",
+		});
+	});
+
+	it("skips only the malformed pair in a realistic OTEL header string", () => {
+		expect(
+			parseKeyPairsIntoRecord(
+				"Authorization=Bearer abc,X-Tenant=acme%,X-Trace=on",
+			),
+		).toEqual({
+			Authorization: "Bearer abc",
+			"X-Trace": "on",
+		});
+	});
+});

sdk/packages/shared/src/parse/headers/utils.ts

@@ -7,11 +7,11 @@ export function parseKeyPairsIntoRecord(
 		return result;
 	}
 
-	try {
-		value.split(",").forEach((entry) => {
-			const separatorIndex = entry.indexOf("=");
-			if (separatorIndex <= 0) return;
+	value.split(",").forEach((entry) => {
+		const separatorIndex = entry.indexOf("=");
+		if (separatorIndex <= 0) return;
 
+		try {
 			// From the beginning to the equal sign is the key, from the equal sign to the end is the value
 			const key = decodeURIComponent(entry.substring(0, separatorIndex).trim());
 			const value = decodeURIComponent(
@@ -21,8 +21,12 @@ export function parseKeyPairsIntoRecord(
 			if (!key || !value) return;
 
 			result[key] = value;
-		});
-	} catch {}
+		} catch {
+			// Skip a single malformed entry (e.g. an invalid percent-encoding
+			// that makes decodeURIComponent throw) rather than aborting the
+			// whole list and silently dropping every remaining pair.
+		}
+	});
 
 	return result;
 }