feat(channel): 添加权重属性以优化通道选择

在 ChannelConfig 中添加了可选的 weight 属性，用于
优化通道的选择逻辑。更新了相关 API 端点以支持
权重的验证和处理。通道选择逻辑现在会优先选择
权重最高的通道，提升请求路由的灵活性和效率。

frontend/src/types/index.ts

@@ -14,6 +14,7 @@ export interface ChannelConfig {
   type: 'openai' | 'gemini' | 'azure-openai' | 'openai-audio' | 'azure-openai-audio' | 'claude' | 'claude-to-openai' | 'openai-responses' | 'azure-openai-responses'
   endpoint: string
   enabled?: boolean
+  weight?: number
   api_key?: string
   api_keys?: string[]
   auto_retry?: boolean

src/admin/channel_api.ts

@@ -155,7 +155,11 @@ export class ChannelGetEndpoint extends OpenAPIRoute {
 
     async handle(c: Context<HonoCustomType>) {
         const result = await c.env.DB.prepare(
-            "SELECT * FROM channel_config"
+            `SELECT * FROM channel_config
+             ORDER BY
+             COALESCE(CAST(json_extract(value, '$.weight') AS INTEGER), 0) DESC,
+             datetime(created_at) DESC,
+             key ASC`
         ).all<ChannelConfigRow>();
 
         return {
@@ -182,6 +186,7 @@ export class ChannelUpsertEndpoint extends OpenAPIRoute {
                             type: z.string().describe('Channel type'),
                             endpoint: z.string().describe('API endpoint'),
                             enabled: z.boolean().optional().describe('Whether this channel participates in request routing'),
+                            weight: z.number().int().min(0).max(5).optional().describe('Priority weight for channel routing'),
                             api_key: z.string().optional().describe('Deprecated single API key'),
                             api_keys: z.array(z.string()).optional().describe('API keys, one request will pick one randomly'),
                             auto_retry: z.boolean().optional().describe('Automatically retry the same API key'),
@@ -254,6 +259,7 @@ export class ChannelFetchModelsEndpoint extends OpenAPIRoute {
                             type: z.string().optional(),
                             endpoint: z.string().optional(),
                             enabled: z.boolean().optional(),
+                            weight: z.number().int().min(0).max(5).optional(),
                             api_key: z.string().optional(),
                             api_keys: z.array(z.string()).optional(),
                             auto_retry: z.boolean().optional(),

src/channel-config.ts

@@ -1,12 +1,15 @@
 export const DEFAULT_CHANNEL_AUTO_RETRY = true;
 export const DEFAULT_CHANNEL_AUTO_ROTATE = true;
 export const DEFAULT_CHANNEL_ENABLED = true;
+export const DEFAULT_CHANNEL_WEIGHT = 0;
+export const MAX_CHANNEL_WEIGHT = 5;
 export const DEFAULT_CLAUDE_API_VERSION = "2023-06-01";
 export const MAX_RETRIES_PER_KEY = 3;
 export const MAX_ROTATION_ATTEMPTS = 3;
 
-export type NormalizedChannelConfig = Omit<ChannelConfig, "enabled" | "api_keys" | "auto_retry" | "auto_rotate" | "models" | "supported_models" | "deployment_mapper"> & {
+export type NormalizedChannelConfig = Omit<ChannelConfig, "enabled" | "weight" | "api_keys" | "auto_retry" | "auto_rotate" | "models" | "supported_models" | "deployment_mapper"> & {
     enabled: boolean;
+    weight: number;
     api_keys: string[];
     auto_retry: boolean;
     auto_rotate: boolean;
@@ -15,6 +18,15 @@ export type NormalizedChannelConfig = Omit<ChannelConfig, "enabled" | "api_keys"
     deployment_mapper: Record<string, string>;
 };
 
+const normalizeChannelWeight = (weight: unknown): number => {
+    if (typeof weight !== "number" || !Number.isFinite(weight)) {
+        return DEFAULT_CHANNEL_WEIGHT;
+    }
+
+    const normalizedWeight = Math.trunc(weight);
+    return Math.min(MAX_CHANNEL_WEIGHT, Math.max(DEFAULT_CHANNEL_WEIGHT, normalizedWeight));
+};
+
 const normalizeApiKeys = (config: Partial<ChannelConfig>): string[] => {
     const rawKeys = Array.isArray(config.api_keys)
         ? [...config.api_keys]
@@ -108,6 +120,7 @@ export const normalizeChannelConfig = (
         type: config.type,
         endpoint: config.endpoint || "",
         enabled: config.enabled ?? DEFAULT_CHANNEL_ENABLED,
+        weight: normalizeChannelWeight(config.weight),
         api_key: typeof config.api_key === "string" ? config.api_key.trim() : undefined,
         api_keys: normalizeApiKeys(config),
         auto_retry: config.auto_retry ?? DEFAULT_CHANNEL_AUTO_RETRY,
@@ -129,6 +142,7 @@ export const sanitizeChannelConfig = (
         type: normalized.type,
         endpoint: normalized.endpoint,
         enabled: normalized.enabled,
+        weight: normalized.weight,
         api_keys: normalized.api_keys,
         auto_retry: normalized.auto_retry,
         auto_rotate: normalized.auto_rotate,

src/constants.ts

@@ -1,6 +1,6 @@
 export const CONSTANTS = {
     VERSION: "v0.0.1",
     DB_VERSION_KEY: "db_version",
-    DB_VERSION: "v0.0.4",
+    DB_VERSION: "v0.0.5",
     MODEL_PRICING_KEY: "MODEL_PRICING_CONFIG",
 }

src/providers/shared/channel-resolver.ts

@@ -103,8 +103,14 @@ export const resolveChannel = async (
         return c.text(`Model not supported: ${requestedModel}. Please configure models.`, 400);
     }
 
-    const randomIndex = Math.floor(Math.random() * availableChannels.length);
-    const selectedChannel = availableChannels[randomIndex];
+    const maxWeight = availableChannels.reduce((highest, current) => {
+        return Math.max(highest, current.config.weight ?? 0);
+    }, 0);
+    const highestPriorityChannels = availableChannels.filter((channel) => {
+        return (channel.config.weight ?? 0) === maxWeight;
+    });
+    const randomIndex = Math.floor(Math.random() * highestPriorityChannels.length);
+    const selectedChannel = highestPriorityChannels[randomIndex];
     const targetChannelKey = selectedChannel.key;
     const targetChannelConfig = selectedChannel.config;
     const trackingState: RequestTrackingState = {

type.d.ts

@@ -71,6 +71,7 @@ type ChannelConfig = {
     type: ChannelType;
     endpoint: string;
     enabled?: boolean;
+    weight?: number;
     api_key?: string;
     api_keys?: string[];
     auto_retry?: boolean;