Override start_span so Instana IDs are used via generate_id

Author: pglombardo

instana/tracer.py

@@ -1,9 +1,14 @@
+import time
 from basictracer import BasicTracer
 import instana.recorder as r
 import opentracing
 import instana.options as o
 import instana.sensor as s
 
+from basictracer.context import SpanContext
+from basictracer.span import BasicSpan
+from instana.util import generate_id
+
 
 class InstanaTracer(BasicTracer):
     sensor = None
@@ -13,6 +18,47 @@ def __init__(self, options=o.Options()):
         super(InstanaTracer, self).__init__(
             r.InstanaRecorder(self.sensor), r.InstanaSampler())
 
+    def start_span(
+            self,
+            operation_name=None,
+            child_of=None,
+            references=None,
+            tags=None,
+            start_time=None):
+        "Taken from BasicTracer so we can override generate_id calls to ours"
+
+        start_time = time.time() if start_time is None else start_time
+
+        # See if we have a parent_ctx in `references`
+        parent_ctx = None
+        if child_of is not None:
+            parent_ctx = (
+                child_of if isinstance(child_of, opentracing.SpanContext)
+                else child_of.context)
+        elif references is not None and len(references) > 0:
+            # TODO only the first reference is currently used
+            parent_ctx = references[0].referenced_context
+
+        # Assemble the child ctx
+        ctx = SpanContext(span_id=generate_id())
+        if parent_ctx is not None:
+            if parent_ctx._baggage is not None:
+                ctx._baggage = parent_ctx._baggage.copy()
+            ctx.trace_id = parent_ctx.trace_id
+            ctx.sampled = parent_ctx.sampled
+        else:
+            ctx.trace_id = generate_id()
+            ctx.sampled = self.sampler.sampled(ctx.trace_id)
+
+        # Tie it all together
+        return BasicSpan(
+            self,
+            operation_name=operation_name,
+            context=ctx,
+            parent_id=(None if parent_ctx is None else parent_ctx.span_id),
+            tags=tags,
+            start_time=start_time)
+
 
 def init(options):
     opentracing.tracer = InstanaTracer(options)