Development Guide
Payment Account
Merchants can apply for a payment method on the WeChat Official Account Admin Platform (for Native Quick Pay and Official Account Payment) or the WeChat Open Platform (for In-App Payment) as instructed. After the WeChat payment staff receives and reviews the application, the corresponding payment permission will be opened for the Merchant. The Merchant will then receive an email containing required payment instructions from the WeChat Payment Assistant, as shown in Figure 4.1.
Figure 4.1 Email Template for Application Approval
Table 4.1 shows the relation between email parameters and API parameters.
Table 4.1 Account parameters
| Parameters in Email | API Parameter Name | Description |
|---|---|---|
| APPID | appid | appid is a unique identity key for each application within the WeChat Official Account Admin Platform or WeChat Open Platform, and is assigned by WeChat after developers apply for it on these platforms. The application approval email also contains this field. |
| Merchant ID for WeChat Payment | mch_id | Specifies merchant's receipt ID assigned by WeChat Payment after they have applied for WeChat Payment |
| API Key | key | This key is created for transaction signatures and is retained in the Merchant’s backend and WeChat payment system, and should not be made available publicly or on the internet. The Merchant should keep this key secured and avoid disclosing it to others. Merchants may configure the key according to the email instructions. |
| Appsecret | secret | AppSecret is the API password corresponding to APPID, and is used to obtain a certificate (access_token) for calling API access_token. Using WeChat payment, you should obtain an OpenID via the OAuth2.0 interface and use it within the single interface for Official Account Payment. Developers shall be qualified to get AppSecret in development mode. |
Access Nodes for Payment API
There are two access nodes for payment API for overseas merchants:
Server deployed in east-southern Asia: https://apihk.mch.weixin.qq.com
Server deployed in China: https://api.mch.weixin.qq.com
Note: Merchants should choose the best access node for payment API according to their server deployed area. It is advised to consider the compatibility for other access nodes. Once there is problem about the main node, the system could automatically switch to the other nodes.
