Add a DDTrace\generate_distributed_tracing_headers() function

It's a direct opposite function to consume_distributed_tracing_headers, thereby trivially enabling users to use it for custom propoagation and later consumption. Also needed for easy testing of parametric tests. And force phpunit < 10 to fix tests.
DataDog · Feb 3, 2023 · 8c8c475 · 8c8c475
1 parent fed56e0
commit 8c8c475
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Showing 7 changed files with 77 additions and 28 deletions.
diff --git a/composer.json b/composer.json
@@ -28,7 +28,7 @@
         "ext-posix": "*",
         "g1a/composer-test-scenarios": "~3.0",
         "mockery/mockery": "*",
-        "phpunit/phpunit": "*",
+        "phpunit/phpunit": "<10",
         "squizlabs/php_codesniffer": "^3.3.0",
         "symfony/process": "<5"
     },

diff --git a/ext/ddtrace.c b/ext/ddtrace.c
@@ -39,6 +39,7 @@
 #include "dogstatsd_client.h"
 #include "engine_hooks.h"
 #include "excluded_modules.h"
+#include "handlers_http.h"
 #include "handlers_internal.h"
 #include "integrations/integrations.h"
 #include "ip_extraction.h"
@@ -2005,6 +2006,16 @@ static PHP_FUNCTION(consume_distributed_tracing_headers) {
     RETURN_NULL();
 }
 
+/* {{{ proto array generate_distributed_tracing_headers() */
+static PHP_FUNCTION(generate_distributed_tracing_headers) {
+    UNUSED(execute_data);
+
+    array_init(return_value);
+    if (get_DD_TRACE_ENABLED()) {
+        ddtrace_inject_distributed_headers(Z_ARR_P(return_value), true);
+    }
+}
+
 /* {{{ proto string dd_trace_closed_spans_count() */
 static PHP_FUNCTION(dd_trace_closed_spans_count) {
     UNUSED(execute_data);
@@ -2126,6 +2137,7 @@ static const zend_function_entry ddtrace_functions[] = {
     DDTRACE_NS_FE(current_context, arginfo_ddtrace_void),
     DDTRACE_NS_FE(set_distributed_tracing_context, arginfo_dd_trace_set_distributed_tracing_context),
     DDTRACE_NS_FE(consume_distributed_tracing_headers, arginfo_consume_distributed_tracing_headers),
+    DDTRACE_NS_FE(generate_distributed_tracing_headers, arginfo_ddtrace_void),
     DDTRACE_FE(dd_trace_reset, arginfo_ddtrace_void),
     DDTRACE_FE(dd_trace_send_traces_via_thread, arginfo_dd_trace_send_traces_via_thread),
     DDTRACE_FE(dd_trace_serialize_closed_spans, arginfo_ddtrace_void),

diff --git a/ext/handlers_curl.c b/ext/handlers_curl.c
@@ -77,7 +77,7 @@ static void dd_inject_distributed_tracing_headers(zend_object *ch) {
         array_init(&headers);
     }
 
-    ddtrace_inject_distributed_headers(Z_ARR(headers));
+    ddtrace_inject_distributed_headers(Z_ARR(headers), false);
 
     zend_function *setopt_fn = zend_hash_str_find_ptr(EG(function_table), ZEND_STRL("curl_setopt"));
 

diff --git a/ext/handlers_curl_php7.c b/ext/handlers_curl_php7.c
@@ -130,7 +130,7 @@ static int dd_inject_distributed_tracing_headers(zval *ch) {
         array_init(&headers);
     }
 
-    ddtrace_inject_distributed_headers(Z_ARR(headers));
+    ddtrace_inject_distributed_headers(Z_ARR(headers), false);
 
     zend_function *setopt_fn = zend_hash_str_find_ptr(EG(function_table), ZEND_STRL("curl_setopt"));
 

diff --git a/ext/handlers_http.h b/ext/handlers_http.h
@@ -7,10 +7,17 @@
 
 ZEND_EXTERN_MODULE_GLOBALS(ddtrace);
 
-static inline void ddtrace_inject_distributed_headers(zend_array *array) {
+static inline void ddtrace_inject_distributed_headers(zend_array *array, bool key_value_pairs) {
     zval headers;
     ZVAL_ARR(&headers, array);
 
+#define ADD_HEADER(header, ...) \
+    if (key_value_pairs) { \
+        add_assoc_str_ex(&headers, ZEND_STRL(header), zend_strpprintf(0, __VA_ARGS__)); \
+    } else { \
+        add_next_index_str(&headers, zend_strpprintf(0, header ": " __VA_ARGS__)); \
+    }
+
     zend_array *inject = zai_config_is_modified(DDTRACE_CONFIG_DD_TRACE_PROPAGATION_STYLE)
                          && !zai_config_is_modified(DDTRACE_CONFIG_DD_TRACE_PROPAGATION_STYLE_INJECT)
                          ? get_DD_TRACE_PROPAGATION_STYLE() : get_DD_TRACE_PROPAGATION_STYLE_INJECT();
@@ -23,54 +30,53 @@ static inline void ddtrace_inject_distributed_headers(zend_array *array) {
     zend_long sampling_priority = ddtrace_fetch_prioritySampling_from_root();
     if (sampling_priority != DDTRACE_PRIORITY_SAMPLING_UNKNOWN) {
         if (send_datadog) {
-            add_next_index_str(&headers,
-                               zend_strpprintf(0, "x-datadog-sampling-priority: " ZEND_LONG_FMT, sampling_priority));
+            ADD_HEADER("x-datadog-sampling-priority", ZEND_LONG_FMT, sampling_priority);
         }
         if (send_b3) {
             if (sampling_priority <= 0) {
-                add_next_index_string(&headers, "X-B3-Sampled: 0");
+                ADD_HEADER("x-b3-sampled", "0");
             } else if (sampling_priority == PRIORITY_SAMPLING_USER_KEEP) {
-                add_next_index_string(&headers, "X-B3-Flags: 1");
+                ADD_HEADER("x-b3-flags", "1");
             } else {
-                add_next_index_string(&headers, "X-B3-Sampled: 1");
+                ADD_HEADER("x-b3-sampled", "1");
             }
         }
     }
     zend_string *propagated_tags = ddtrace_format_propagated_tags();
     if (send_datadog || send_b3 || send_b3single) {
         if (propagated_tags) {
-            add_next_index_str(&headers, zend_strpprintf(0, "x-datadog-tags: %s", ZSTR_VAL(propagated_tags)));
+            ADD_HEADER("x-datadog-tags", "%s", ZSTR_VAL(propagated_tags));
         }
         if (DDTRACE_G(dd_origin)) {
-            add_next_index_str(&headers, zend_strpprintf(0, "x-datadog-origin: %s", ZSTR_VAL(DDTRACE_G(dd_origin))));
+            ADD_HEADER("x-datadog-origin", "%s", ZSTR_VAL(DDTRACE_G(dd_origin)));
         }
     }
     ddtrace_trace_id trace_id = ddtrace_peek_trace_id();
     uint64_t span_id = ddtrace_peek_span_id();
     if (trace_id.low || trace_id.high) {
         if (send_datadog) {
-            add_next_index_str(&headers, zend_strpprintf(0, "x-datadog-trace-id: %" PRIu64, trace_id.low));
+            ADD_HEADER("x-datadog-trace-id", "%" PRIu64, trace_id.low);
         }
         if (send_b3) {
             if (trace_id.high) {
-                add_next_index_str(&headers, zend_strpprintf(0, "X-B3-TraceId: %016" PRIx64 "%016" PRIx64, trace_id.high, trace_id.low));
+                ADD_HEADER("X-B3-TraceId", "%016" PRIx64 "%016" PRIx64, trace_id.high, trace_id.low);
             } else {
-                add_next_index_str(&headers, zend_strpprintf(0, "X-B3-TraceId: %016" PRIx64, trace_id.low));
+                ADD_HEADER("X-B3-TraceId", "%016" PRIx64, trace_id.low);
             }
         }
         if (span_id) {
             if (send_datadog) {
-                add_next_index_str(&headers, zend_strpprintf(0, "x-datadog-parent-id: %" PRIu64, span_id));
+                ADD_HEADER("x-datadog-parent-id", "%" PRIu64, span_id);
             }
             if (send_b3) {
-                add_next_index_str(&headers, zend_strpprintf(0, "X-B3-SpanId: %016" PRIx64, span_id));
+                ADD_HEADER("X-B3-SpanId", "%016" PRIx64, span_id);
             }
             if (send_tracestate) {
-                add_next_index_str(&headers, zend_strpprintf(0, "traceparent: 00-%016" PRIx64 "%016" PRIx64 "-%016" PRIx64 "-%02" PRIx8,
-                                                             trace_id.high,
-                                                             trace_id.low,
-                                                             span_id,
-                                                             sampling_priority > 0));
+                ADD_HEADER("traceparent", "00-%016" PRIx64 "%016" PRIx64 "-%016" PRIx64 "-%02" PRIx8,
+                           trace_id.high,
+                           trace_id.low,
+                           span_id,
+                           sampling_priority > 0);
 
                 smart_str str = {0};
 
@@ -138,7 +144,7 @@ static inline void ddtrace_inject_distributed_headers(zend_array *array) {
                 }
 
                 if (str.s) {
-                    add_next_index_str(&headers, zend_strpprintf(0, "tracestate: %s%.*s", hasdd ? "dd=" : "", (int)ZSTR_LEN(str.s), ZSTR_VAL(str.s)));
+                    ADD_HEADER("tracestate", "%s%.*s", hasdd ? "dd=" : "", (int)ZSTR_LEN(str.s), ZSTR_VAL(str.s));
                     smart_str_free(&str);
                 }
             }
@@ -163,16 +169,18 @@ static inline void ddtrace_inject_distributed_headers(zend_array *array) {
             } else {
                 sprintf(trace_id_buf, "%016" PRIx64, trace_id.low);
             }
-            add_next_index_str(&headers, zend_strpprintf(0, "b3: %s-%016" PRIx64 "%s%s",
-                                                         trace_id_buf,
-                                                         span_id,
-                                                         b3_sampling_decision ? "-" : "", b3_sampling_decision ? b3_sampling_decision : ""));
+            ADD_HEADER("b3", "%s-%016" PRIx64 "%s%s",
+                       trace_id_buf,
+                       span_id,
+                       b3_sampling_decision ? "-" : "", b3_sampling_decision ? b3_sampling_decision : "");
         } else if (b3_sampling_decision) {
-            add_next_index_str(&headers, zend_strpprintf(0, "b3: %s", b3_sampling_decision));
+            ADD_HEADER("b3", "%s", b3_sampling_decision);
         }
     }
 
     if (propagated_tags) {
         zend_string_release(propagated_tags);
     }
 }
+
+#undef ADD_HEADER
diff --git a/tests/composer.json b/tests/composer.json
@@ -8,7 +8,7 @@
     },
     "require-dev": {
         "mockery/mockery": "*",
-        "phpunit/phpunit": "*",
+        "phpunit/phpunit": "<10",
         "phpspec/prophecy": "*",
         "symfony/process": "<5",
         "g1a/composer-test-scenarios": "~3.0"

diff --git a/tests/ext/distributed_tracing/distributed_trace_generate.phpt b/tests/ext/distributed_tracing/distributed_trace_generate.phpt
@@ -0,0 +1,29 @@
+--TEST--
+Test generate_distributed_tracing_headers()
+--ENV--
+HTTP_X_DATADOG_TRACE_ID=42
+HTTP_X_DATADOG_PARENT_ID=10
+HTTP_X_DATADOG_ORIGIN=datadog
+HTTP_X_DATADOG_SAMPLING_PRIORITY=3
+DD_TRACE_GENERATE_ROOT_SPAN=0
+--FILE--
+<?php
+
+var_dump(DDTrace\generate_distributed_tracing_headers());
+
+?>
+--EXPECT--
+array(6) {
+  ["x-datadog-sampling-priority"]=>
+  string(1) "3"
+  ["x-datadog-origin"]=>
+  string(7) "datadog"
+  ["x-datadog-trace-id"]=>
+  string(2) "42"
+  ["x-datadog-parent-id"]=>
+  string(2) "10"
+  ["traceparent"]=>
+  string(55) "00-0000000000000000000000000000002a-000000000000000a-01"
+  ["tracestate"]=>
+  string(16) "dd=o:datadog;s:3"
+}