feat: AI 代理 Wasm 插件对接 Mistral (#1257)

Co-authored-by: Kent Dong <ch3cho@qq.com>

plugins/wasm-go/extensions/ai-proxy/README.md

@@ -138,6 +138,10 @@ Groq 所对应的 `type` 为 `groq`。它并无特有的配置字段。
 
 360智脑所对应的 `type` 为 `ai360`。它并无特有的配置字段。
 
+#### Mistral
+
+Mistral 所对应的 `type` 为 `mistral`。它并无特有的配置字段。
+
 #### MiniMax
 
 MiniMax所对应的 `type` 为 `minimax`。它特有的配置字段如下：

plugins/wasm-go/extensions/ai-proxy/provider/mistral.go

@@ -0,0 +1,80 @@
+package provider
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/alibaba/higress/plugins/wasm-go/extensions/ai-proxy/util"
+	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
+	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
+	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
+)
+
+const (
+	mistralDomain = "api.mistral.ai"
+)
+
+type mistralProviderInitializer struct{}
+
+func (m *mistralProviderInitializer) ValidateConfig(config ProviderConfig) error {
+	if config.apiTokens == nil || len(config.apiTokens) == 0 {
+		return errors.New("no apiToken found in provider config")
+	}
+	return nil
+}
+
+func (m *mistralProviderInitializer) CreateProvider(config ProviderConfig) (Provider, error) {
+	return &mistralProvider{
+		config:       config,
+		contextCache: createContextCache(&config),
+	}, nil
+}
+
+type mistralProvider struct {
+	config       ProviderConfig
+	contextCache *contextCache
+}
+
+func (m *mistralProvider) GetProviderType() string {
+	return providerTypeMistral
+}
+
+func (m *mistralProvider) OnRequestHeaders(ctx wrapper.HttpContext, apiName ApiName, log wrapper.Log) (types.Action, error) {
+	if apiName != ApiNameChatCompletion {
+		return types.ActionContinue, errUnsupportedApiName
+	}
+	_ = util.OverwriteRequestHost(mistralDomain)
+	_ = util.OverwriteRequestAuthorization("Bearer " + m.config.GetRandomToken())
+	_ = proxywasm.RemoveHttpRequestHeader("Content-Length")
+	return types.ActionContinue, nil
+}
+
+func (m *mistralProvider) OnRequestBody(ctx wrapper.HttpContext, apiName ApiName, body []byte, log wrapper.Log) (types.Action, error) {
+	if apiName != ApiNameChatCompletion {
+		return types.ActionContinue, errUnsupportedApiName
+	}
+	if m.contextCache == nil {
+		return types.ActionContinue, nil
+	}
+	request := &chatCompletionRequest{}
+	if err := decodeChatCompletionRequest(body, request); err != nil {
+		return types.ActionContinue, err
+	}
+	err := m.contextCache.GetContent(func(content string, err error) {
+		defer func() {
+			_ = proxywasm.ResumeHttpRequest()
+		}()
+		if err != nil {
+			log.Errorf("failed to load context file: %v", err)
+			_ = util.SendResponse(500, "ai-proxy.mistral.load_ctx_failed", util.MimeTypeTextPlain, fmt.Sprintf("failed to load context file: %v", err))
+		}
+		insertContextMessage(request, content)
+		if err := replaceJsonRequestBody(request, log); err != nil {
+			_ = util.SendResponse(500, "ai-proxy.mistral.insert_ctx_failed", util.MimeTypeTextPlain, fmt.Sprintf("failed to replace request body: %v", err))
+		}
+	}, log)
+	if err == nil {
+		return types.ActionPause, nil
+	}
+	return types.ActionContinue, err
+}

plugins/wasm-go/extensions/ai-proxy/provider/provider.go

@@ -37,6 +37,7 @@ const (
 	providerTypeSpark      = "spark"
 	providerTypeGemini     = "gemini"
 	providerTypeDeepl      = "deepl"
+	providerTypeMistral    = "mistral"
 
 	protocolOpenAI   = "openai"
 	protocolOriginal = "original"
@@ -92,6 +93,7 @@ var (
 		providerTypeSpark:      &sparkProviderInitializer{},
 		providerTypeGemini:     &geminiProviderInitializer{},
 		providerTypeDeepl:      &deeplProviderInitializer{},
+		providerTypeMistral:    &mistralProviderInitializer{},
 	}
 )