feat: support ollama ai model (#1001)

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

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

@@ -93,6 +93,15 @@ Anthropic Claude 所对应的 `type` 为 `claude`。它特有的配置字段如
 |-----------|--------|-----|-----|-------------------|
 | `version` | string | 必填  | -   | Claude 服务的 API 版本 |
 
+#### Ollama
+
+Ollama 所对应的 `type` 为 `ollama`。它特有的配置字段如下：
+
+| 名称                | 数据类型   | 填写要求 | 默认值 | 描述                                           |
+|-------------------|--------|------|-----|----------------------------------------------|
+| `ollamaServerHost` | string | 必填   | -   | Ollama 服务器的主机地址 |
+| `ollamaServerPort` | number | 必填   | -   | Ollama 服务器的端口号，默认为11434 |
+
 ## 用法示例
 
 ### 使用 OpenAI 协议代理 Azure OpenAI 服务

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

@@ -0,0 +1,114 @@
+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"
+)
+
+// ollamaProvider is the provider for Ollama service.
+
+const (
+	ollamaChatCompletionPath = "/v1/chat/completions"
+)
+
+type ollamaProviderInitializer struct {
+}
+
+func (m *ollamaProviderInitializer) ValidateConfig(config ProviderConfig) error {
+	if config.ollamaServerHost == "" {
+		return errors.New("missing ollamaServerHost in provider config")
+	}
+	if config.ollamaServerPort == 0 {
+		return errors.New("missing ollamaServerPort in provider config")
+	}
+	return nil
+}
+
+func (m *ollamaProviderInitializer) CreateProvider(config ProviderConfig) (Provider, error) {
+	serverPortStr := fmt.Sprintf("%d", config.ollamaServerPort)
+	serviceDomain := config.ollamaServerHost + ":" + serverPortStr
+	return &ollamaProvider{
+		config:        config,
+		serviceDomain: serviceDomain,
+		contextCache:  createContextCache(&config),
+	}, nil
+}
+
+type ollamaProvider struct {
+	config        ProviderConfig
+	serviceDomain string
+	contextCache  *contextCache
+}
+
+func (m *ollamaProvider) GetProviderType() string {
+	return providerTypeOllama
+}
+
+func (m *ollamaProvider) OnRequestHeaders(ctx wrapper.HttpContext, apiName ApiName, log wrapper.Log) (types.Action, error) {
+	if apiName != ApiNameChatCompletion {
+		return types.ActionContinue, errUnsupportedApiName
+	}
+	_ = util.OverwriteRequestPath(ollamaChatCompletionPath)
+	_ = util.OverwriteRequestHost(m.serviceDomain)
+	_ = proxywasm.RemoveHttpRequestHeader("Content-Length")
+
+	return types.ActionContinue, nil
+}
+
+func (m *ollamaProvider) OnRequestBody(ctx wrapper.HttpContext, apiName ApiName, body []byte, log wrapper.Log) (types.Action, error) {
+	if apiName != ApiNameChatCompletion {
+		return types.ActionContinue, errUnsupportedApiName
+	}
+
+	if m.config.modelMapping == nil && m.contextCache == nil {
+		return types.ActionContinue, nil
+	}
+	
+	request := &chatCompletionRequest{}
+	if err := decodeChatCompletionRequest(body, request); err != nil {
+		return types.ActionContinue, err
+	}
+
+	model := request.Model
+	if model == "" {
+		return types.ActionContinue, errors.New("missing model in chat completion request")
+	}
+	mappedModel := getMappedModel(model, m.config.modelMapping, log)
+	if mappedModel == "" {
+		return types.ActionContinue, errors.New("model becomes empty after applying the configured mapping")
+	}
+	request.Model = mappedModel
+	
+	if m.contextCache != nil {
+		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, util.MimeTypeTextPlain, fmt.Sprintf("failed to load context file: %v", err))
+			}
+			insertContextMessage(request, content)
+			if err := replaceJsonRequestBody(request, log); err != nil {
+				_ = util.SendResponse(500, util.MimeTypeTextPlain, fmt.Sprintf("failed to replace request body: %v", err))
+			}
+		}, log)
+		if err == nil {
+			return types.ActionPause, nil
+		} else {
+			return types.ActionContinue, err
+		}
+	} else {
+		if err := replaceJsonRequestBody(request, log); err != nil {
+			_ = util.SendResponse(500, util.MimeTypeTextPlain, fmt.Sprintf("failed to replace request body: %v", err))
+			return types.ActionContinue, err
+		}
+		_ = proxywasm.ResumeHttpRequest()
+		return types.ActionPause, nil
+	}
+}

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

@@ -23,6 +23,7 @@ const (
 	providerTypeBaichuan = "baichuan"
 	providerTypeYi       = "yi"
 	providerTypeDeepSeek = "deepseek"
+	providerTypeOllama   = "ollama"
 
 	protocolOpenAI   = "openai"
 	protocolOriginal = "original"
@@ -60,6 +61,7 @@ var (
 		providerTypeBaichuan: &baichuanProviderInitializer{},
 		providerTypeYi:       &yiProviderInitializer{},
 		providerTypeDeepSeek: &deepseekProviderInitializer{},
+		providerTypeOllama:   &ollamaProviderInitializer{},
 	}
 )
 
@@ -89,7 +91,7 @@ type ResponseBodyHandler interface {
 
 type ProviderConfig struct {
 	// @Title zh-CN AI服务提供商
-	// @Description zh-CN AI服务提供商类型，目前支持的取值为："moonshot"、"qwen"、"openai"、"azure"、"baichuan"、"yi"
+	// @Description zh-CN AI服务提供商类型，目前支持的取值为："moonshot"、"qwen"、"openai"、"azure"、"baichuan"、"yi"、"ollama"
 	typ string `required:"true" yaml:"type" json:"type"`
 	// @Title zh-CN API Tokens
 	// @Description zh-CN 在请求AI服务时用于认证的API Token列表。不同的AI服务提供商可能有不同的名称。部分供应商只支持配置一个API Token（如Azure OpenAI）。
@@ -109,6 +111,12 @@ type ProviderConfig struct {
 	// @Title zh-CN 启用通义千问搜索服务
 	// @Description zh-CN 仅适用于通义千问服务，表示是否启用通义千问的互联网搜索功能。
 	qwenEnableSearch bool `required:"false" yaml:"qwenEnableSearch" json:"qwenEnableSearch"`
+	// @Title zh-CN Ollama Server IP/Domain
+	// @Description zh-CN 仅适用于 Ollama 服务。Ollama 服务器的主机地址。
+	ollamaServerHost string `required:"false" yaml:"ollamaServerHost" json:"ollamaServerHost"`
+	// @Title zh-CN Ollama Server Port
+	// @Description zh-CN 仅适用于 Ollama 服务。Ollama 服务器的端口号。
+	ollamaServerPort uint32 `required:"false" yaml:"ollamaServerPort" json:"ollamaServerPort"`
 	// @Title zh-CN 模型名称映射表
 	// @Description zh-CN 用于将请求中的模型名称映射为目标AI服务商支持的模型名称。支持通过“*”来配置全局映射
 	modelMapping map[string]string `required:"false" yaml:"modelMapping" json:"modelMapping"`
@@ -137,6 +145,8 @@ func (c *ProviderConfig) FromJson(json gjson.Result) {
 		c.qwenFileIds = append(c.qwenFileIds, fileId.String())
 	}
 	c.qwenEnableSearch = json.Get("qwenEnableSearch").Bool()
+	c.ollamaServerHost = json.Get("ollamaServerHost").String()
+	c.ollamaServerPort = uint32(json.Get("ollamaServerPort").Uint())
 	c.modelMapping = make(map[string]string)
 	for k, v := range json.Get("modelMapping").Map() {
 		c.modelMapping[k] = v.String()