extend ai-prompt-decorator plugin with client's geographic message from geo-ip plugin (#1228)

plugins/wasm-go/extensions/ai-prompt-decorator/README.md

@@ -66,4 +66,70 @@ curl http://localhost/test \
     }
   ]
 }
-```
+```
+
+
+# 基于geo-ip插件的能力，扩展AI提示词装饰器插件携带用户地理位置信息
+如果需要在LLM的请求前后加入用户地理位置信息，请确保同时开启geo-ip插件和AI提示词装饰器插件。并且在相同的请求处理阶段里，geo-ip插件的优先级必须高于AI提示词装饰器插件。首先geo-ip插件会根据用户ip计算出用户的地理位置信息，然后通过请求属性传递给后续插件。比如在默认阶段里，geo-ip插件的priority配置1000，ai-prompt-decorator插件的priority配置500。
+
+geo-ip插件配置示例：
+```yaml
+ipProtocal: "ipv4"
+```
+
+
+
+
+AI提示词装饰器插件的配置示例如下：
+```yaml
+prepend:
+- role: system
+  content: "提问用户当前的地理位置信息是，国家：${geo-country}，省份：${geo-province}, 城市：${geo-city}"
+append:
+- role: user
+  content: "每次回答完问题，尝试进行反问"
+```
+
+使用以上配置发起请求：
+
+```bash
+curl http://localhost/test \
+-H "content-type: application/json" \
+-H "x-forwarded-for: 87.254.207.100,4.5.6.7" \
+-d '{
+  "model": "gpt-3.5-turbo",
+  "messages": [
+    {
+      "role": "user",
+      "content": "今天天气怎么样？"
+    }
+  ]
+}'
+```
+
+经过插件处理后，实际请求为：
+
+```bash
+curl http://localhost/test \
+-H "content-type: application/json" \
+-H "x-forwarded-for: 87.254.207.100,4.5.6.7" \
+-d '{
+  "model": "gpt-3.5-turbo",
+  "messages": [
+    {
+      "role": "system",
+      "content": "提问用户当前的地理位置信息是，国家：中国，省份：北京, 城市：北京"
+    },
+    {
+      "role": "user",
+      "content": "今天天气怎么样？"
+    },
+    {
+      "role": "user",
+      "content": "每次回答完问题，尝试进行反问"
+    }
+  ]
+}'
+```
+
+

plugins/wasm-go/extensions/ai-prompt-decorator/main.go

@@ -2,6 +2,8 @@ package main
 
 import (
 	"encoding/json"
+	"fmt"
+	"strings"
 
 	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
@@ -38,10 +40,42 @@ func onHttpRequestHeaders(ctx wrapper.HttpContext, config AIPromptDecoratorConfi
 	return types.ActionContinue
 }
 
+func replaceVariable(variable string, entry *Message) (*Message, error) {
+	key := fmt.Sprintf("${%s}", variable)
+	if strings.Contains(entry.Content, key) {
+		value, err := proxywasm.GetProperty([]string{variable})
+		if err != nil {
+			return nil, err
+		}
+		entry.Content = strings.ReplaceAll(entry.Content, key, string(value))
+	}
+	return entry, nil
+}
+
+func decorateGeographicPrompt(entry *Message) (*Message, error) {
+	geoArr := []string{"geo-country", "geo-province", "geo-city", "geo-isp"}
+
+	var err error
+	for _, geo := range geoArr {
+		entry, err = replaceVariable(geo, entry)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return entry, nil
+}
+
 func onHttpRequestBody(ctx wrapper.HttpContext, config AIPromptDecoratorConfig, body []byte, log wrapper.Log) types.Action {
 	messageJson := `{"messages":[]}`
 
 	for _, entry := range config.Prepend {
+		entry, err := decorateGeographicPrompt(&entry)
+		if err != nil {
+			log.Errorf("Failed to decorate geographic prompt in prepend, error: %v", err)
+			return types.ActionContinue
+		}
+
 		msg, err := json.Marshal(entry)
 		if err != nil {
 			log.Errorf("Failed to add prepend message, error: %v", err)
@@ -60,6 +94,12 @@ func onHttpRequestBody(ctx wrapper.HttpContext, config AIPromptDecoratorConfig,
 	}
 
 	for _, entry := range config.Append {
+		entry, err := decorateGeographicPrompt(&entry)
+		if err != nil {
+			log.Errorf("Failed to decorate geographic prompt in append, error: %v", err)
+			return types.ActionContinue
+		}
+
 		msg, err := json.Marshal(entry)
 		if err != nil {
 			log.Errorf("Failed to add prepend message, error: %v", err)