Parse platform 解析云代码中的request.context是如何工作的?
在Parse Server 3.0更新中,添加了request.context以在BeforeSave和AfterSave之间传递数据,如下所述: 但是,我在理解Parse如何以及何时在示例中运行此代码时遇到了一些困难Parse platform 解析云代码中的request.context是如何工作的?,parse-platform,parse-cloud-code,Parse Platform,Parse Cloud Code,在Parse Server 3.0更新中,添加了request.context以在BeforeSave和AfterSave之间传递数据,如下所述: 但是,我在理解Parse如何以及何时在示例中运行此代码时遇到了一些困难 const beforeSave = function beforeSave(request) { const { object: role } = request; // Get users that will be added to the users relati
const beforeSave = function beforeSave(request) {
const { object: role } = request;
// Get users that will be added to the users relation.
const usersOp = role.op('users');
if (usersOp && usersOp.relationsToAdd.length > 0) {
// add the users being added to the request context
request.context = { buyers: usersOp.relationsToAdd };
}
};
const afterSave = function afterSave(request) {
const { object: role, context } = request;
if (context && context.buyers) {
const purchasedItem = getItemFromRole(role);
const promises = context.buyers.map(emailBuyer.bind(null, purchasedItem));
item.increment('orderCount', context.buyers.length);
promises.push(item.save(null, { useMasterKey: true }));
Promise.all(promises).catch(request.log.error.bind(request.log));
}
};
在其他示例中,云代码函数通过Parse.cloud.beforeSave或Parse.cloud.afterSave运行。在上面的示例中,将函数beforeSave分配给
节约之前节约
为什么要这样做?应该放在main.js顶层还是另一个函数中