Fix ExporterInterface (#150)

* Remove accessors from Span. Add Span#spanData which returns its SpanData

* ExporterInterface is now export(array )

* Fix extension test

* Fix doc for EchoExporter

* Mock StackdriverExporter client for tests

* Missed spot to mock Stackdriver client

Author: chingor13

composer.json

@@ -18,7 +18,7 @@
         "cache/adapter-common": "^1.0"
     },
     "require-dev": {
-        "phpunit/phpunit": ">= 4.8",
+        "phpunit/phpunit": ">= 6.0",
         "squizlabs/php_codesniffer": "2.*",
         "google/cloud-trace": "^0.4",
         "twig/twig": "~2.0",

src/Trace/Exporter/EchoExporter.php

@@ -17,7 +17,7 @@
 
 namespace OpenCensus\Trace\Exporter;
 
-use OpenCensus\Trace\Tracer\TracerInterface;
+use OpenCensus\Trace\SpanData;
 
 /**
  * This implementation of the ExporterInterface uses `print_r` to output
@@ -37,12 +37,12 @@ class EchoExporter implements ExporterInterface
     /**
      * Report the provided Trace to a backend.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
-        print_r($tracer->spans());
+        print_r($spans);
         return true;
     }
 }

src/Trace/Exporter/ExporterInterface.php

@@ -17,18 +17,18 @@
 
 namespace OpenCensus\Trace\Exporter;
 
-use OpenCensus\Trace\Tracer\TracerInterface;
+use OpenCensus\Trace\SpanData;
 
 /**
  * The ExporterInterface allows you to swap out the Trace reporting mechanism
  */
 interface ExporterInterface
 {
     /**
-     * Report the provided Trace to a backend.
+     * Export the provided SpanData to a backend.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer);
+    public function export(array $spans);
 }

src/Trace/Exporter/FileExporter.php

@@ -17,7 +17,7 @@
 
 namespace OpenCensus\Trace\Exporter;
 
-use OpenCensus\Trace\Span;
+use OpenCensus\Trace\SpanData;
 use OpenCensus\Trace\Tracer\TracerInterface;
 
 /**
@@ -51,30 +51,28 @@ public function __construct($filename)
     }
 
     /**
-     * Report the provided Trace to a backend.
+     * Report the provided SpanData to a file in json format.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
-        $spans = $this->convertSpans($tracer);
+        $spans = $this->convertSpans($spans);
         return file_put_contents($this->filename, json_encode($spans) . PHP_EOL, FILE_APPEND) !== false;
     }
 
     /**
      * Convert spans into array ready for serialization.
      *
-     * @param TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return array Representation of the collected trace spans ready for serialization
      */
-    private function convertSpans(TracerInterface $tracer)
+    private function convertSpans(array $spans)
     {
-        $traceId = $tracer->spanContext()->traceId();
-
-        return array_map(function (Span $span) use ($traceId) {
+        return array_map(function (SpanData $span) use ($traceId) {
             return [
-                'traceId' => $traceId,
+                'traceId' => $span->traceId(),
                 'name' => $span->name(),
                 'spanId' => $span->spanId(),
                 'parentSpanId' => $span->parentSpanId(),
@@ -87,6 +85,6 @@ private function convertSpans(TracerInterface $tracer)
                 'links' => $span->links(),
                 'sameProcessAsParentSpan' => $span->sameProcessAsParentSpan(),
             ];
-        }, $tracer->spans());
+        }, $spans);
     }
 }

src/Trace/Exporter/LoggerExporter.php

@@ -17,7 +17,7 @@
 
 namespace OpenCensus\Trace\Exporter;
 
-use OpenCensus\Trace\Tracer\TracerInterface;
+use OpenCensus\Trace\SpanData;
 use Psr\Log\LoggerInterface;
 
 /**
@@ -65,13 +65,13 @@ public function __construct(LoggerInterface $logger, $level = self::DEFAULT_LOG_
     /**
      * Report the provided Trace to a backend.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
         try {
-            $this->logger->log($this->level, json_encode($tracer->spans()));
+            $this->logger->log($this->level, json_encode($spans));
         } catch (\Exception $e) {
             error_log('Reporting the Trace data failed: ' . $e->getMessage());
             return false;

src/Trace/Exporter/NullExporter.php

@@ -36,10 +36,10 @@ class NullExporter implements ExporterInterface
     /**
      * Does nothing.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
         return true;
     }

src/Trace/Exporter/StackdriverExporter.php

@@ -22,8 +22,8 @@
 use Google\Cloud\Trace\TraceClient;
 use Google\Cloud\Trace\Span;
 use Google\Cloud\Trace\Trace;
-use OpenCensus\Trace\Tracer\TracerInterface;
 use OpenCensus\Trace\Span as OCSpan;
+use OpenCensus\Trace\SpanData;
 
 /**
  * This implementation of the ExporterInterface use the BatchRunner to provide
@@ -135,19 +135,20 @@ public function __construct(array $options = [])
     /**
      * Report the provided Trace to a backend.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
-        $spans = $this->convertSpans($tracer);
+        $spans = $this->convertSpans($spans);
 
         if (empty($spans)) {
             return false;
         }
 
+        // Pull the traceId from the first span
         $trace = self::$client->trace(
-            $tracer->spanContext()->traceId()
+            $spans[0]->traceId()
         );
 
         // build a Trace object and assign Spans
@@ -170,16 +171,16 @@ public function report(TracerInterface $tracer)
      *
      * @access private
      *
-     * @param TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return Span[] Representation of the collected trace spans ready for serialization
      */
-    public function convertSpans(TracerInterface $tracer)
+    public function convertSpans(array $spans)
     {
         // transform OpenCensus Spans to Google\Cloud\Trace\Spans
-        return array_map([$this, 'mapSpan'], $tracer->spans());
+        return array_map([$this, 'mapSpan'], $spans);
     }
 
-    private function mapSpan($span)
+    private function mapSpan(SpanData $span)
     {
         return new Span($span->traceId(), [
             'name' => $span->name(),

src/Trace/Exporter/ZipkinExporter.php

@@ -18,8 +18,7 @@
 namespace OpenCensus\Trace\Exporter;
 
 use OpenCensus\Trace\MessageEvent;
-use OpenCensus\Trace\Tracer\TracerInterface;
-use OpenCensus\Trace\Span;
+use OpenCensus\Trace\SpanData;
 
 /**
  * This implementation of the ExporterInterface appends a json
@@ -96,12 +95,12 @@ public function setLocalIpv6($ipv6)
     /**
      * Report the provided Trace to a backend.
      *
-     * @param  TracerInterface $tracer
+     * @param SpanData[] $spans
      * @return bool
      */
-    public function report(TracerInterface $tracer)
+    public function export(array $spans)
     {
-        $spans = $this->convertSpans($tracer);
+        $spans = $this->convertSpans($spans);
 
         if (empty($spans)) {
             return false;
@@ -129,15 +128,13 @@ public function report(TracerInterface $tracer)
      * Convert spans into Zipkin's expected JSON output format. See
      * <a href="http://zipkin.io/zipkin-api/#/default/post_spans">output format definition</a>.
      *
-     * @param TracerInterface $tracer
+     * @param SpanData[] $spans
      * @param array $headers [optional] HTTP headers to parse. **Defaults to** $_SERVER
      * @return array Representation of the collected trace spans ready for serialization
      */
-    public function convertSpans(TracerInterface $tracer, $headers = null)
+    public function convertSpans(array $spans, $headers = null)
     {
         $headers = $headers ?: $_SERVER;
-        $spans = $tracer->spans();
-        $traceId = $tracer->spanContext()->traceId();
 
         // True is a request to store this span even if it overrides sampling policy.
         // This is true when the X-B3-Flags header has a value of 1.
@@ -154,6 +151,7 @@ public function convertSpans(TracerInterface $tracer, $headers = null)
             $parentSpanId = $span->parentSpanId()
                 ? str_pad($span->parentSpanId(), 16, '0', STR_PAD_LEFT)
                 : null;
+            $traceId = str_pad($span->traceId(), 32, '0', STR_PAD_LEFT);
 
             $attributes = $span->attributes();
             if (empty($attributes)) {
@@ -184,7 +182,7 @@ public function convertSpans(TracerInterface $tracer, $headers = null)
         return $zipkinSpans;
     }
 
-    private function spanKind(Span $span)
+    private function spanKind(SpanData $span)
     {
         if (strpos($span->name(), 'Sent.') === 0) {
             return self::KIND_CLIENT;

src/Trace/RequestHandler.php

@@ -47,7 +47,7 @@ class RequestHandler
     /**
      * @var ExporterInterface The reported to use at the end of the request
      */
-    private $reporter;
+    private $exporter;
 
     /**
      * @var TracerInterface The tracer to use for this request
@@ -72,7 +72,7 @@ class RequestHandler
     /**
      * Create a new RequestHandler.
      *
-     * @param ExporterInterface $reporter How to report the trace at the end of the request
+     * @param ExporterInterface $exporter How to report the trace at the end of the request
      * @param SamplerInterface $sampler Which sampler to use for sampling requests
      * @param PropagatorInterface $propagator SpanContext propagator
      * @param array $options [optional] {
@@ -85,12 +85,12 @@ class RequestHandler
      * }
      */
     public function __construct(
-        ExporterInterface $reporter,
+        ExporterInterface $exporter,
         SamplerInterface $sampler,
         PropagatorInterface $propagator,
         array $options = []
     ) {
-        $this->reporter = $reporter;
+        $this->exporter = $exporter;
         $this->headers = array_key_exists('headers', $options)
             ? $options['headers']
             : $_SERVER;
@@ -135,7 +135,12 @@ public function onExit()
         $this->addCommonRequestAttributes($this->headers);
 
         $this->scope->close();
-        $this->reporter->report($this->tracer);
+
+        // Fetch the SpanData of all the collected Spans
+        $spans = array_map(function (Span $span) {
+            return $span->spanData();
+        }, $this->tracer->spans());
+        $this->exporter->export($spans);
     }
 
     /**