fix(tracer): error when encoding bytes and adding a string [backport #13419 to 2.21] (#14084)

fixes error when we try to concat the string 'truncated' to bytes

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- The change includes tests OR the PR description describes a testing
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- The PR description notes risks associated with the change, if any
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---------



(cherry picked from commit 2e13f18)

---------

Co-authored-by: Rachel Yang <[email protected]>
Co-authored-by: Quinna Halim <[email protected]>
Co-authored-by: Brett Langdon <[email protected]>

Author: 4 people

ddtrace/internal/_encoding.pyx

@@ -96,7 +96,10 @@ cdef inline int array_prefix_size(stdint.uint32_t l):
 
 cdef inline object truncate_string(object string):
     if string and len(string) > MAX_SPAN_META_VALUE_LEN:
-        return string[:TRUNCATED_SPAN_ATTRIBUTE_LEN - 14] + "<truncated>..."
+        if PyBytesLike_Check(string):
+            return string[:TRUNCATED_SPAN_ATTRIBUTE_LEN - 14] + b"<truncated>..."
+        elif PyUnicode_Check(string):
+            return string[:TRUNCATED_SPAN_ATTRIBUTE_LEN - 14] + "<truncated>..."
     return string
 
 cdef inline int pack_bytes(msgpack_packer *pk, char *bs, Py_ssize_t l):

releasenotes/notes/encode-bytes-974d93cec3725455.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    tracing: This resolves a ``TypeError`` in encoding when truncating a large bytes object.

tests/integration/test_integration_snapshots.py

@@ -278,9 +278,7 @@ def test_snapshot_skip():
 @parametrize_with_all_encodings
 @mark_snapshot
 def test_setting_span_tags_and_metrics_generates_no_error_logs():
-    import ddtrace
-
-    s = ddtrace.tracer.trace("operation", service="my-svc")
+    s = tracer.trace("operation", service="my-svc")
     s.set_tag("env", "my-env")
     s.set_metric("number1", 123)
     s.set_metric("number2", 12.0)
@@ -296,3 +294,28 @@ def test_encode_span_with_large_string_attributes(encoding):
     with override_global_config(dict(_trace_api=encoding)):
         with tracer.trace(name="a" * 25000, resource="b" * 25001) as span:
             span.set_tag(key="c" * 25001, value="d" * 2000)
+
+
+@pytest.mark.parametrize("encoding", ["v0.4", "v0.5"])
+@pytest.mark.snapshot()
+def test_encode_span_with_large_bytes_attributes(encoding):
+    from ddtrace import tracer
+
+    with override_global_config(dict(_trace_api=encoding)):
+        name = b"a" * 25000
+        resource = b"b" * 25001
+        key = b"c" * 25001
+        value = b"d" * 2000
+
+        with tracer.trace(name=name, resource=resource) as span:
+            span.set_tag(key=key, value=value)
+
+
+@pytest.mark.parametrize("encoding", ["v0.4", "v0.5"])
+@pytest.mark.snapshot()
+def test_encode_span_with_large_unicode_string_attributes(encoding):
+    from ddtrace import tracer
+
+    with override_global_config(dict(_trace_api=encoding)):
+        with tracer.trace(name="á" * 25000, resource="â" * 25001) as span:
+            span.set_tag(key="å" * 25001, value="ä" * 2000)