Generate Auth URL

Updated: 7/26/26, 9:23:52 PM

Description

Used to obtain the OAuth authorization URL for fetching user openId / userId in scenarios like WeChat JSAPI, Alipay Mini Program, UnionPay QuickPass, etc.

Flow:

1. Merchant backend calls this endpoint to get authUrl (with session token) and queryCode.
2. Merchant frontend redirects the user's browser to authUrl for the channel to complete OAuth.
3. After authorization, the channel calls back the platform, which associates the session via queryCode.
4. Merchant obtains openId via Auth Code or polls with queryCode.

This is "fetch openId", not "login"

This endpoint obtains a channel user identifier (openId/userId) before payment. It does NOT involve merchant-system login state.

Request

POST /unipay/assist/channel/auth/generate-auth-url

• Auth: RSA signature (@PaymentVerify)
• Response: DaxResult<AuthUrlResult>

Parameters

Common params same as Pay - Common Parameters. Business parameters:

Parameter	Type	Required	Max	Description
authType	string	No	32	Auth type (wechat/alipay/union_pay/douyin; defaults to wechat)
product	string	No	32	Payment product code (determines auth strategy; looked up from channelMchNo if missing)
channelAppId	string	No	128	Channel App ID to use (overrides auto-resolve; must be pre-configured)
returnPath	string	No	200	Source redirect path (where frontend lands after auth; saved with session)
capability	string	No	32	Payment capability code (resolves specific app: Official Account / Mini Program)

Example

{
  "mchNo": "M200000001",
  "appId": "APP001",
  "reqId": "REQ20241201020",
  "reqTime": "2024-12-01 12:00:00",
  "sign": "Base64Signature",
  "authType": "wechat",
  "returnPath": "/pay/result"
}

Response

DaxResult<AuthUrlResult>, data fields:

Field	Type	Description
authUrl	string	Authorization URL (frontend redirects here)
queryCode	string	Query identifier (used by Auth Code to restore context)

Example

{
  "code": 0,
  "msg": "success",
  "data": {
    "authUrl": "https://open.weixin.qq.com/connect/oauth2/authorize?appid=...&state=...",
    "queryCode": "QC20241201020"
  },
  "sign": "Base64Signature",
  "resTime": "2024-12-01T04:00:00Z",
  "reqId": "REQ20241201020"
}

Docs for AI Assistants

LLM-friendly document formats for ChatGPT, Claude, Cursor and other AI tools to read and understand DaxPay docs.

llms.txt — Site index, page list with summaries for quick lookup
llms-full.txt — Full docs merged, complete content in one file for bulk AI input