Merge pull request #5 from NFIBrokerage/conform-headers

Use b3 headers

lib/hummingbird.ex

@@ -3,9 +3,7 @@ defmodule Hummingbird do
   Ships the conn to honeycomb.io to allow distributed tracing.
 
   Assumes requests that come in populate two different headers:
-  request-from-trace-id
-  and
-  request-from-span-id
+  x-b3-traceid and x-b3-spanid
   """
 
   use Plug.Builder
@@ -21,8 +19,7 @@ defmodule Hummingbird do
   end
 
   @doc """
-  In this case, is an impure dispatching of conn information to the elixir
-  honeycomb client
+  An impure dispatching of conn information to the elixir honeycomb client
   """
   def call(conn, opts) do
     conn =
@@ -104,7 +101,7 @@ defmodule Hummingbird do
     if is_nil(conn.assigns[:span_id]) do
       # wasn't set previously so check header
       conn
-      |> get_req_header("request-from-span-id")
+      |> get_req_header("x-b3-spanid")
       |> List.first()
     else
       conn.assigns[:span_id]
@@ -118,7 +115,7 @@ defmodule Hummingbird do
   def determine_trace_id(conn) do
     if is_nil(conn.assigns[:trace_id]) do
       conn
-      |> get_req_header("request-from-trace-id")
+      |> get_req_header("x-b3-traceid")
       |> List.first() || UUID.uuid4()
     else
       # fallback to this being an internal responsibility to assign a trace id

test/hummingbird_test.exs

@@ -9,7 +9,7 @@ defmodule HummingbirdTest do
     ]
   end
 
-  describe "given no request-from-trace-id header," do
+  describe "given no x-b3-traceid header," do
     setup do
       [
         conn_without_header: conn(:get, "/foo")
@@ -25,7 +25,7 @@ defmodule HummingbirdTest do
     end
   end
 
-  describe "given no request-from-span-id header," do
+  describe "given no x-b3-spanid header," do
     setup do
       [
         conn_without_header: conn(:get, "/foo")
@@ -43,15 +43,15 @@ defmodule HummingbirdTest do
     end
   end
 
-  describe "given a conn with request-from-trace-id header," do
+  describe "given a conn with x-b3-traceid header," do
     setup do
       expected_id = UUID.uuid4()
 
       [
         expected_id: expected_id,
         conn_with_header:
           conn(:get, "/foo")
-          |> put_req_header("request-from-trace-id", expected_id)
+          |> put_req_header("x-b3-traceid", expected_id)
       ]
     end
 
@@ -64,7 +64,7 @@ defmodule HummingbirdTest do
     end
   end
 
-  describe "given a conn with nil trace id and no request-from-trace-id header," do
+  describe "given a conn with nil trace id and no x-b3-traceid header," do
     setup do
       expected_id = UUID.uuid4()
 
@@ -84,15 +84,15 @@ defmodule HummingbirdTest do
     end
   end
 
-  describe "given a conn with request-from-span-id header," do
+  describe "given a conn with x-b3-spanid header," do
     setup do
       expected_id = UUID.uuid4()
 
       [
         expected_id: expected_id,
         conn_with_header:
           conn(:get, "/foo")
-          |> put_req_header("request-from-span-id", expected_id)
+          |> put_req_header("x-b3-spanid", expected_id)
       ]
     end
 
@@ -106,7 +106,7 @@ defmodule HummingbirdTest do
     end
   end
 
-  describe "given a conn with no request-from-span-id header," do
+  describe "given a conn with no x-b3-spanid header," do
     setup do
       [
         conn_without_header: conn(:get, "/foo")
@@ -136,8 +136,8 @@ defmodule HummingbirdTest do
           |> assign(:span_id, expected_parent_id)
           |> assign(:trace_id, expected_trace_id)
           |> assign(:parent_id, UUID.uuid4())
-          |> put_req_header("request-from-span-id", UUID.uuid4())
-          |> put_req_header("request-from-trace-id", UUID.uuid4())
+          |> put_req_header("x-b3-spanid", UUID.uuid4())
+          |> put_req_header("x-b3-traceid", UUID.uuid4())
       ]
     end