feat: add zipkin variable

apisix/cli/ngx_tpl.lua

@@ -643,6 +643,14 @@ http {
         {% end %}
         # opentelemetry_set_ngx_var ends
 
+        # zipkin_set_ngx_var starts
+        {% if zipkin_set_ngx_var then %}
+        set $zipkin_context_traceparent          '';
+        set $zipkin_trace_id                     '';
+        set $zipkin_span_id                      '';
+        {% end %}
+        # zipkin_set_ngx_var ends
+
         # http server configuration snippet starts
         {% if http_server_configuration_snippet then %}
         {* http_server_configuration_snippet *}

apisix/cli/ops.lua

@@ -546,6 +546,11 @@ Please modify "admin_key" in conf/config.yaml .
     if enabled_plugins["opentelemetry"] and yaml_conf.plugin_attr["opentelemetry"] then
         opentelemetry_set_ngx_var = yaml_conf.plugin_attr["opentelemetry"].set_ngx_var
     end
+
+    local zipkin_set_ngx_var
+    if enabled_plugins["zipkin"] and yaml_conf.plugin_attr["zipkin"] then
+        zipkin_set_ngx_var = yaml_conf.plugin_attr["zipkin"].set_ngx_var
+    end
     -- Using template.render
     local sys_conf = {
         lua_path = env.pkg_path_org,
@@ -566,7 +571,8 @@ Please modify "admin_key" in conf/config.yaml .
         control_server_addr = control_server_addr,
         prometheus_server_addr = prometheus_server_addr,
         proxy_mirror_timeouts = proxy_mirror_timeouts,
-        opentelemetry_set_ngx_var = opentelemetry_set_ngx_var
+        opentelemetry_set_ngx_var = opentelemetry_set_ngx_var,
+        zipkin_set_ngx_var = zipkin_set_ngx_var
     }
 
     if not yaml_conf.apisix then

apisix/plugins/zipkin.lua

@@ -20,13 +20,17 @@ local zipkin_codec = require("apisix.plugins.zipkin.codec")
 local new_random_sampler = require("apisix.plugins.zipkin.random_sampler").new
 local new_reporter = require("apisix.plugins.zipkin.reporter").new
 local ngx = ngx
+local ngx_var = ngx.var
 local ngx_re = require("ngx.re")
 local pairs = pairs
 local tonumber = tonumber
+local to_hex = require "resty.string".to_hex
 
 local plugin_name = "zipkin"
 local ZIPKIN_SPAN_VER_1 = 1
 local ZIPKIN_SPAN_VER_2 = 2
+local plugin = require("apisix.plugin")
+local string_format = string.format
 
 
 local lrucache = core.lrucache.new({
@@ -69,6 +73,8 @@ function _M.check_schema(conf)
     return core.schema.check(schema, conf)
 end
 
+local plugin_info  = plugin.plugin_attr(plugin_name) or {}
+
 
 local function create_tracer(conf,ctx)
     conf.route_id = ctx.route_id
@@ -205,9 +211,23 @@ function _M.rewrite(plugin_conf, ctx)
     ctx.opentracing_sample = tracer.sampler:sample(per_req_sample_ratio or conf.sample_ratio)
     if not ctx.opentracing_sample then
         request_span:set_baggage_item("x-b3-sampled","0")
+    else
+       request_span:set_baggage_item("x-b3-sampled","1")
+    end
+
+    if plugin_info.set_ngx_var then
+        local span_context = request_span:context()
+        ngx_var.zipkin_context_traceparent = string_format("00-%s-%s-%02x", 
+                                             to_hex(span_context.trace_id),
+                                             to_hex(span_context.span_id),
+                                             span_context:get_baggage_item("x-b3-sampled"))
+        ngx_var.zipkin_trace_id = span_context.trace_id
+        ngx_var.zipkin_span_id = span_context.span_id
+    end
+
+    if not ctx.opentracing_sample then
         return
     end
-    request_span:set_baggage_item("x-b3-sampled","1")
 
     local request_span = ctx.opentracing.request_span
     if conf.span_version == ZIPKIN_SPAN_VER_1 then
@@ -218,7 +238,7 @@ function _M.rewrite(plugin_conf, ctx)
     else
         ctx.opentracing.proxy_span = request_span:start_child_span("apisix.proxy",
                                                                    start_timestamp)
-    end
+    end   
 end
 
 function _M.access(conf, ctx)

conf/config-default.yaml

@@ -616,6 +616,8 @@ plugin_attr:          # Plugin attributes
     hooks_file: "/usr/local/apisix/plugin_inspect_hooks.lua"  # Set the path to the Lua file that defines
                                                               # hooks. Only administrators should have
                                                               # write access to this file for security.
+  zipkin:                             # Plugin: zipkin
+    set_ngx_var: false                # export zipkin variables to nginx variables
 
 deployment:                    # Deployment configurations
   role: traditional            # Set deployment mode: traditional, control_plane, or data_plane.

docs/en/latest/plugins/zipkin.md

@@ -235,3 +235,32 @@ curl http://127.0.0.1:9180/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f13
     }
 }'
 ```
+
+## Variables
+
+The following nginx variables are set by zipkin:
+
+- `zipkin_context_traceparent` -  [W3C trace context](https://www.w3.org/TR/trace-context/#trace-context-http-headers-format), e.g.: `00-0af7651916cd43dd8448eb211c80319c-b9c7c989f97918e1-01`
+- `zipkin_trace_id` - Trace Id of the current span
+- `zipkin_span_id` -  Span Id of the current span
+
+How to use variables? you have to add it to your configuration file (`conf/config.yaml`):
+
+```yaml title="./conf/config.yaml"
+http:
+    enable_access_log: true
+    access_log: "/dev/stdout"
+    access_log_format: '{"time": "$time_iso8601","zipkin_context_traceparent": "$zipkin_context_traceparent","zipkin_trace_id": "$zipkin_trace_id","zipkin_span_id": "$zipkin_span_id","remote_addr": "$remote_addr","uri": "$uri"}'
+    access_log_format_escape: json
+plugins:
+  - zipkin
+plugin_attr:
+  zipkin:
+    set_ngx_var: true
+```
+
+You can also include a trace_id when printing logs
+
+```print error log
+log.error(ngx_var.zipkin_trace_id,"error message")
+```

docs/zh/latest/plugins/zipkin.md

@@ -235,3 +235,32 @@ curl http://127.0.0.1:9180/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f13
     }
 }'
 ```
+
+## 如何使用变量
+
+以下`nginx`变量是由`zipkin` 设置的。
+
+- `zipkin_context_traceparent` -  [W3C trace context](https://www.w3.org/TR/trace-context/#trace-context-http-headers-format), 例如：`00-0af7651916cd43dd8448eb211c80319c-b9c7c989f97918e1-01`
+- `zipkin_trace_id` - 当前 span 的 trace_id
+- `zipkin_span_id` - 当前 span 的 span_id
+
+如何使用？你需要在配置文件（`./conf/config.yaml`）设置如下：
+
+```yaml title="./conf/config.yaml"
+http:
+    enable_access_log: true
+    access_log: "/dev/stdout"
+    access_log_format: '{"time": "$time_iso8601","zipkin_context_traceparent": "$zipkin_context_traceparent","zipkin_trace_id": "$zipkin_trace_id","zipkin_span_id": "$zipkin_span_id","remote_addr": "$remote_addr","uri": "$uri"}'
+    access_log_format_escape: json
+plugins:
+  - zipkin
+plugin_attr:
+  zipkin:
+    set_ngx_var: true
+```
+
+你也可以在打印日志的时候带上trace_id
+
+```print error log
+log.error(ngx_var.zipkin_trace_id,"error message")
+```

t/cli/test_zipkin_set_ngx_var.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+. ./t/cli/common.sh
+
+echo '
+plugins:
+    - zipkin
+plugin_attr:
+  zipkin:
+    set_ngx_var: true
+' > conf/config.yaml
+
+make init
+
+if ! grep "set \$zipkin_context_traceparent          '';" conf/nginx.conf > /dev/null; then
+    echo "failed: zipkin_context_traceparent not found in nginx.conf"
+    exit 1
+fi
+
+if ! grep "set \$zipkin_trace_id                     '';" conf/nginx.conf > /dev/null; then
+    echo "failed: zipkin_trace_id not found in nginx.conf"
+    exit 1
+fi
+
+if ! grep "set \$zipkin_span_id                      '';" conf/nginx.conf > /dev/null; then
+    echo "failed: zipkin_span_id not found in nginx.conf"
+    exit 1
+fi
+
+echo "passed: zipkin_set_ngx_var configuration is validated"

t/plugin/zipkin3.t

@@ -0,0 +1,132 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+use t::APISIX 'no_plan';
+
+repeat_each(1);
+no_long_string();
+no_root_location();
+log_level("info");
+
+add_block_preprocessor(sub {
+    my ($block) = @_;
+
+    if (!$block->extra_yaml_config) {
+        my $extra_yaml_config = <<_EOC_;
+plugins:
+    - zipkin
+plugin_attr:
+    zipkin:
+        set_ngx_var: true
+_EOC_
+        $block->set_value("extra_yaml_config", $extra_yaml_config);
+    }
+
+    my $upstream_server_config = $block->upstream_server_config // <<_EOC_;
+        set \$zipkin_context_traceparent "";
+        set \$zipkin_trace_id "";
+        set \$zipkin_span_id "";
+_EOC_
+
+    $block->set_value("upstream_server_config", $upstream_server_config);
+
+    my $extra_init_by_lua = <<_EOC_;
+    local zipkin = require("apisix.plugins.zipkin")
+    local orig_func = zipkin.access
+    zipkin.access = function (...)
+        local traceparent = ngx.var.zipkin_context_traceparent
+        if traceparent == nil or traceparent == '' then
+           ngx.log(ngx.ERR,"ngx_var.zipkin_context_traceparent is empty")
+        else
+            ngx.log(ngx.ERR,"ngx_var.zipkin_context_traceparent:",ngx.var.zipkin_context_traceparent)
+        end
+
+        local orig = orig_func(...)
+        return orig
+    end
+_EOC_
+
+    $block->set_value("extra_init_by_lua", $extra_init_by_lua);
+
+    if (!$block->request) {
+            $block->set_value("request", "GET /t");
+    }
+
+    $block;
+});
+
+run_tests;
+
+__DATA__
+
+
+=== TEST 1: add plugin metadata
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/routes/1',
+                 ngx.HTTP_PUT,
+                 [[{
+                        "plugins": {
+                            "zipkin": {
+                                "endpoint": "http://127.0.0.1:9999/mock_zipkin",
+                                "sample_ratio": 1
+                            }
+                        },
+                        "upstream": {
+                            "nodes": {
+                                "127.0.0.1:1980": 1
+                            },
+                            "type": "roundrobin"
+                        },
+                        "uri": "/echo"
+                }]]
+                )
+
+            if code >= 300 then
+                ngx.status = code
+            end
+            ngx.say(body)
+        }
+    }
+--- request
+GET /t
+--- response_body
+passed
+
+
+
+=== TEST 2:  trigger zipkin with open set variables
+--- request
+GET /echo
+--- error_log eval
+qr/ngx_var.zipkin_context_traceparent:00-\w{32}-\w{16}-01*/
+
+
+
+=== TEST 3: trigger zipkin with disable set variables
+--- yaml_config
+plugin_attr:
+    zipkin:
+        set_ngx_var: false
+--- request
+GET /echo
+--- error_log
+ngx_var.zipkin_context_traceparent is empty
+
+