Show how to set custom_tags for tracing

jaeger-tracing/envoy.yaml

@@ -23,6 +23,26 @@ static_resources:
                 collector_endpoint: "/api/v2/spans"
                 shared_span_context: false
                 collector_endpoint_version: HTTP_JSON
+
+            custom_tags:
+            - tag: tag_literal
+              literal:
+                value: literal value
+            - tag: tag_request_header
+              request_header:
+                name: ":path"
+            - tag: tag_env_hostname
+              environment:
+                name: "HOSTNAME"
+            - tag: tag_metadata
+              metadata:
+                kind:
+                  request: {}
+                metadata_key:
+                  key: custom_tag
+                  path:
+                  - key: tag_metadata
+
           codec_type: AUTO
           stat_prefix: ingress_http
           route_config:
@@ -39,6 +59,14 @@ static_resources:
                 decorator:
                   operation: checkAvailability
           http_filters:
+          - name: envoy.filters.http.lua
+            typed_config:
+              '@type': type.googleapis.com/envoy.extensions.filters.http.lua.v3.Lua
+              default_source_code:
+                inline_string: |
+                  function envoy_on_request(response_handle)
+                    response_handle:streamInfo():dynamicMetadata():set("custom_tag", "tag_metadata", "hello from lua")
+                  end
           - name: envoy.filters.http.router
             typed_config:
               "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router

jaeger-tracing/example.rst

@@ -36,6 +36,8 @@ calls to other services. In the sandbox we have provided, the simple ``aiohttp``
 (see trace function in :download:`examples/shared/python/tracing/service.py <_include/shared/python/tracing/service.py>`) acting as service1 propagates
 the trace headers while making an outbound call to service2.
 
+This demo also shows how you can use custom_tags to to attach additional tags of type literal, request header, environment and metadata to the spans.
+
 Step 1: Build the sandbox
 *************************