Add span field meta_struct (#2673)

Add new field meta_struct to the span. This new field is a map where its values are encoded to msgpack and then the resulting codification to msgpack binary
DataDog · Jun 17, 2024 · 5869a12 · 5869a12
1 parent 8959058
commit 5869a12
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Showing 8 changed files with 131 additions and 7 deletions.
diff --git a/ext/ddtrace.c b/ext/ddtrace.c
@@ -708,6 +708,7 @@ static zend_object *dd_init_span_data_object(zend_class_entry *class_type, ddtra
     // Not handled in arginfo on these old versions
     array_init(&span->property_meta);
     array_init(&span->property_metrics);
+    array_init(&span->property_meta_struct);
     array_init(&span->property_links);
     array_init(&span->property_peer_service_sources);
 #endif

diff --git a/ext/ddtrace.stub.php b/ext/ddtrace.stub.php
@@ -94,6 +94,13 @@ class SpanData {
          */
         public string $version = "";
 
+        /**
+         * @var string[] Meta struct can be used to send any data to the backend. The peculiarity of meta struct is
+         * that the values are encoded with msgpack when sent to the agent. The values are first encoded to msgpack
+         * and then, encoded again with msgpack to binary
+         */
+        public array $meta_struct = [];
+
         /**
          * @var string|null The type of request which can be set to: web, db, cache, or custom (Optional). Inherited
          * from parent.

diff --git a/ext/ddtrace_arginfo.h b/ext/ddtrace_arginfo.h
@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 190a99779c21033f0812df6365a7ebdd87057727 */
+ * Stub hash: a92829eefe1ee642b3357f1eef2900f1336e462f */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_DDTrace_trace_method, 0, 3, _IS_BOOL, 0)
 	ZEND_ARG_TYPE_INFO(0, className, IS_STRING, 0)
@@ -565,6 +565,12 @@ static zend_class_entry *register_class_DDTrace_SpanData(void)
 	zend_declare_typed_property(class_entry, property_version_name, &property_version_default_value, ZEND_ACC_PUBLIC, NULL, (zend_type) ZEND_TYPE_INIT_MASK(MAY_BE_STRING));
 	zend_string_release(property_version_name);
 
+	zval property_meta_struct_default_value;
+	ZVAL_EMPTY_ARRAY(&property_meta_struct_default_value);
+	zend_string *property_meta_struct_name = zend_string_init("meta_struct", sizeof("meta_struct") - 1, 1);
+	zend_declare_typed_property(class_entry, property_meta_struct_name, &property_meta_struct_default_value, ZEND_ACC_PUBLIC, NULL, (zend_type) ZEND_TYPE_INIT_MASK(MAY_BE_ARRAY));
+	zend_string_release(property_meta_struct_name);
+
 	zval property_type_default_value;
 	ZVAL_EMPTY_STRING(&property_type_default_value);
 	zend_string *property_type_name = zend_string_init("type", sizeof("type") - 1, 1);

diff --git a/ext/serializer.c b/ext/serializer.c
@@ -63,8 +63,10 @@ static void mpack_write_utf8_lossy_cstr(mpack_writer_t *writer, const char *str,
 #define KEY_TRACE_ID "trace_id"
 #define KEY_SPAN_ID "span_id"
 #define KEY_PARENT_ID "parent_id"
+#define KEY_META_STRUCT "meta_struct"
 
 static int msgpack_write_zval(mpack_writer_t *writer, zval *trace, int level);
+static void serialize_meta_struct(mpack_writer_t *writer, zval *trace);
 
 static int write_hash_table(mpack_writer_t *writer, HashTable *ht, int level) {
     zval *tmp;
@@ -89,6 +91,7 @@ static int write_hash_table(mpack_writer_t *writer, HashTable *ht, int level) {
     ZEND_HASH_FOREACH_KEY_VAL_IND(ht, num_key, string_key, tmp) {
         // Writing the key, if associative
         bool zval_string_as_uint64 = false;
+        bool is_meta_struct = false;
         if (is_assoc == 1) {
             char num_str_buf[MAX_ID_BUFSIZ], *key;
             size_t len;
@@ -105,11 +108,17 @@ static int write_hash_table(mpack_writer_t *writer, HashTable *ht, int level) {
                 (0 == strcmp(KEY_TRACE_ID, key) || 0 == strcmp(KEY_SPAN_ID, key) || 0 == strcmp(KEY_PARENT_ID, key))) {
                 zval_string_as_uint64 = true;
             }
+            if (level <= 3 &&
+                (0 == strcmp(KEY_META_STRUCT, key))) {
+                is_meta_struct = true;
+            }
         }
 
         // Writing the value
         if (zval_string_as_uint64) {
             mpack_write_u64(writer, strtoull(Z_STRVAL_P(tmp), NULL, 10));
+        } else if(is_meta_struct) {
+            serialize_meta_struct(writer, tmp);
         } else if (msgpack_write_zval(writer, tmp, level) != 1) {
             return 0;
         }
@@ -128,7 +137,6 @@ static int msgpack_write_zval(mpack_writer_t *writer, zval *trace, int level) {
     if (Z_TYPE_P(trace) == IS_REFERENCE) {
         trace = Z_REFVAL_P(trace);
     }
-
     switch (Z_TYPE_P(trace)) {
         case IS_ARRAY:
             if (write_hash_table(writer, Z_ARRVAL_P(trace), level + 1) != 1) {
@@ -159,6 +167,26 @@ static int msgpack_write_zval(mpack_writer_t *writer, zval *trace, int level) {
     return 1;
 }
 
+static void serialize_meta_struct(mpack_writer_t *writer, zval *meta_struct) {
+    zval *tmp;
+    zend_string *string_key;
+
+    HashTable *ht = Z_ARRVAL_P(meta_struct);
+
+    mpack_start_map(writer, zend_hash_num_elements(ht));
+
+    ZEND_HASH_FOREACH_STR_KEY_VAL_IND(ht, string_key, tmp) {
+        if (!string_key) {
+            continue;
+        }
+        mpack_write_cstr(writer, ZSTR_VAL(string_key));
+        mpack_write_bin(writer, Z_STRVAL_P(tmp), Z_STRLEN_P(tmp));
+    }
+    ZEND_HASH_FOREACH_END();
+
+    mpack_finish_map(writer);
+}
+
 int ddtrace_serialize_simple_array_into_c_string(zval *trace, char **data_p, size_t *size_p) {
     // encode to memory buffer
     char *data;
@@ -1017,6 +1045,26 @@ static void dd_serialize_array_metrics_recursively(zend_array *target, zend_stri
     dd_serialize_array_recursively(target, str, value, true);
 }
 
+static void dd_serialize_array_meta_struct_recursively(zend_array *target, zend_string *str, zval *value) {
+    char *data;
+    size_t size;
+
+    mpack_writer_t writer;
+    mpack_writer_init_growable(&writer, &data, &size);
+    int result = msgpack_write_zval(&writer, value, 5);
+    mpack_writer_destroy(&writer);
+
+    if (size == 0 || result == 0) {
+        return;
+    }
+
+    zval serialised;
+    ZVAL_STRINGL(&serialised, data, size);
+
+    zend_hash_update(target, str, &serialised);
+    free(data);
+}
+
 struct iter {
     // caller owns key/value
     bool (*next)(struct iter *self, zend_string **key, zend_string **value);
@@ -1426,7 +1474,6 @@ static zend_always_inline double strconv_parse_bool(zend_string *str) {
 
 void ddtrace_serialize_span_to_array(ddtrace_span_data *span, zval *array) {
     bool is_root_span = span->std.ce == ddtrace_ce_root_span_data;
-
     zval *el;
     zval zv;
     el = &zv;
@@ -1794,6 +1841,23 @@ void ddtrace_serialize_span_to_array(ddtrace_span_data *span, zval *array) {
         zend_array_destroy(Z_ARR(metrics_zv));
     }
 
+    zend_array *meta_struct = ddtrace_property_array(&span->property_meta_struct);
+    zval meta_struct_zv;
+    array_init(&meta_struct_zv);
+    zend_string *ms_str_key;
+    zval *ms_val;
+    ZEND_HASH_FOREACH_STR_KEY_VAL_IND(meta_struct, ms_str_key, ms_val) {
+        if (ms_str_key) {
+            dd_serialize_array_meta_struct_recursively(Z_ARRVAL(meta_struct_zv), ms_str_key, ms_val);
+        }
+    }
+    ZEND_HASH_FOREACH_END();
+    if (zend_hash_num_elements(Z_ARR(meta_struct_zv))) {
+        zend_hash_str_add_new(Z_ARR_P(el), ZEND_STRL("meta_struct"), &meta_struct_zv);
+    } else {
+        zend_array_destroy(Z_ARR(meta_struct_zv));
+    }
+
     add_next_index_zval(array, el);
 }
 

diff --git a/ext/span.h b/ext/span.h
@@ -45,6 +45,7 @@ typedef union ddtrace_span_properties {
         zval property_service;
         zval property_env;
         zval property_version;
+        zval property_meta_struct;
         zval property_type;
         zval property_meta;
         zval property_metrics;

diff --git a/tests/ext/active_span.phpt b/tests/ext/active_span.phpt
@@ -28,7 +28,7 @@ var_dump(DDTrace\active_span() == DDTrace\active_span());
 Hello, Datadog.
 greet tracer.
 bool(true)
-object(DDTrace\RootSpanData)#%d (18) {
+object(DDTrace\RootSpanData)#%d (19) {
   ["name"]=>
   string(15) "active_span.php"
   ["resource"]=>
@@ -39,6 +39,9 @@ object(DDTrace\RootSpanData)#%d (18) {
   string(0) ""
   ["version"]=>
   string(0) ""
+  ["meta_struct"]=>
+  array(0) {
+  }
   ["type"]=>
   string(3) "cli"
   ["meta"]=>

diff --git a/tests/ext/meta_struct.phpt b/tests/ext/meta_struct.phpt
@@ -0,0 +1,33 @@
+--TEST--
+Add meta struct string
+--FILE--
+<?php
+function dd_trace_unserialize_trace_hex($meta_struct) {
+    foreach($meta_struct as $key => $value) {
+        $hex = [];
+        $length = strlen($value);
+        for ($i = 0; $i < $length; $i++) {
+            $hex[] = bin2hex($value[$i]);
+        }
+        var_dump($key, implode(' ', $hex));
+    }
+}
+
+$span = DDTrace\start_span();
+$span->meta_struct["foo"] = "bar";
+$span->meta_struct["john"] = ["Doe"];
+DDTrace\close_span();
+
+$spans = dd_trace_serialize_closed_spans();
+
+foreach ($spans as $span)
+{
+    dd_trace_unserialize_trace_hex($span["meta_struct"]);
+}
+
+?>
+--EXPECTF--
+string(3) "foo"
+string(11) "a3 62 61 72"
+string(4) "john"
+string(14) "91 a3 44 6f 65"
diff --git a/tests/ext/sandbox/span_clone.phpt b/tests/ext/sandbox/span_clone.phpt
@@ -24,7 +24,7 @@ var_dump(dd_trace_serialize_closed_spans());
 
 ?>
 --EXPECTF--
-object(DDTrace\RootSpanData)#%d (18) {
+object(DDTrace\RootSpanData)#%d (19) {
   ["name"]=>
   string(3) "foo"
   ["resource"]=>
@@ -35,6 +35,9 @@ object(DDTrace\RootSpanData)#%d (18) {
   string(0) ""
   ["version"]=>
   string(0) ""
+  ["meta_struct"]=>
+  array(0) {
+  }
   ["type"]=>
   string(3) "cli"
   ["meta"]=>
@@ -82,7 +85,7 @@ object(DDTrace\RootSpanData)#%d (18) {
   ["traceId"]=>
   string(32) "%s"
 }
-object(DDTrace\RootSpanData)#%d (18) {
+object(DDTrace\RootSpanData)#%d (19) {
   ["name"]=>
   string(5) "dummy"
   ["resource"]=>
@@ -93,6 +96,9 @@ object(DDTrace\RootSpanData)#%d (18) {
   string(0) ""
   ["version"]=>
   string(0) ""
+  ["meta_struct"]=>
+  array(0) {
+  }
   ["type"]=>
   string(3) "cli"
   ["meta"]=>
@@ -127,7 +133,7 @@ object(DDTrace\RootSpanData)#%d (18) {
       NULL
     }
     ["active"]=>
-    object(DDTrace\RootSpanData)#%d (18) {
+    object(DDTrace\RootSpanData)#%d (19) {
       ["name"]=>
       string(3) "foo"
       ["resource"]=>
@@ -138,6 +144,9 @@ object(DDTrace\RootSpanData)#%d (18) {
       string(0) ""
       ["version"]=>
       string(0) ""
+      ["meta_struct"]=>
+      array(0) {
+      }
       ["type"]=>
       string(3) "cli"
       ["meta"]=>