some progress

node_modules/mongoose/lib/helpers/model/applyHooks.js

@@ -0,0 +1,149 @@
+'use strict';
+
+const symbols = require('../../schema/symbols');
+const promiseOrCallback = require('../promiseOrCallback');
+
+/*!
+ * ignore
+ */
+
+module.exports = applyHooks;
+
+/*!
+ * ignore
+ */
+
+applyHooks.middlewareFunctions = [
+  'deleteOne',
+  'save',
+  'validate',
+  'remove',
+  'updateOne',
+  'init'
+];
+
+/*!
+ * ignore
+ */
+
+const alreadyHookedFunctions = new Set(applyHooks.middlewareFunctions.flatMap(fn => ([fn, `$__${fn}`])));
+
+/**
+ * Register hooks for this model
+ *
+ * @param {Model} model
+ * @param {Schema} schema
+ * @param {Object} options
+ * @api private
+ */
+
+function applyHooks(model, schema, options) {
+  options = options || {};
+
+  const kareemOptions = {
+    useErrorHandlers: true,
+    numCallbackParams: 1,
+    nullResultByDefault: true,
+    contextParameter: true
+  };
+  const objToDecorate = options.decorateDoc ? model : model.prototype;
+
+  model.$appliedHooks = true;
+  for (const key of Object.keys(schema.paths)) {
+    const type = schema.paths[key];
+    let childModel = null;
+    if (type.$isSingleNested) {
+      childModel = type.caster;
+    } else if (type.$isMongooseDocumentArray) {
+      childModel = type.Constructor;
+    } else {
+      continue;
+    }
+
+    if (childModel.$appliedHooks) {
+      continue;
+    }
+
+    applyHooks(childModel, type.schema, options);
+    if (childModel.discriminators != null) {
+      const keys = Object.keys(childModel.discriminators);
+      for (const key of keys) {
+        applyHooks(childModel.discriminators[key],
+          childModel.discriminators[key].schema, options);
+      }
+    }
+  }
+
+  // Built-in hooks rely on hooking internal functions in order to support
+  // promises and make it so that `doc.save.toString()` provides meaningful
+  // information.
+
+  const middleware = schema.s.hooks.
+    filter(hook => {
+      if (hook.name === 'updateOne' || hook.name === 'deleteOne') {
+        return !!hook['document'];
+      }
+      if (hook.name === 'remove' || hook.name === 'init') {
+        return hook['document'] == null || !!hook['document'];
+      }
+      if (hook.query != null || hook.document != null) {
+        return hook.document !== false;
+      }
+      return true;
+    }).
+    filter(hook => {
+      // If user has overwritten the method, don't apply built-in middleware
+      if (schema.methods[hook.name]) {
+        return !hook.fn[symbols.builtInMiddleware];
+      }
+
+      return true;
+    });
+
+  model._middleware = middleware;
+
+  objToDecorate.$__originalValidate = objToDecorate.$__originalValidate || objToDecorate.$__validate;
+
+  for (const method of ['save', 'validate', 'remove', 'deleteOne']) {
+    const toWrap = method === 'validate' ? '$__originalValidate' : `$__${method}`;
+    const wrapped = middleware.
+      createWrapper(method, objToDecorate[toWrap], null, kareemOptions);
+    objToDecorate[`$__${method}`] = wrapped;
+  }
+  objToDecorate.$__init = middleware.
+    createWrapperSync('init', objToDecorate.$__init, null, kareemOptions);
+
+  // Support hooks for custom methods
+  const customMethods = Object.keys(schema.methods);
+  const customMethodOptions = Object.assign({}, kareemOptions, {
+    // Only use `checkForPromise` for custom methods, because mongoose
+    // query thunks are not as consistent as I would like about returning
+    // a nullish value rather than the query. If a query thunk returns
+    // a query, `checkForPromise` causes infinite recursion
+    checkForPromise: true
+  });
+  for (const method of customMethods) {
+    if (alreadyHookedFunctions.has(method)) {
+      continue;
+    }
+    if (!middleware.hasHooks(method)) {
+      // Don't wrap if there are no hooks for the custom method to avoid
+      // surprises. Also, `createWrapper()` enforces consistent async,
+      // so wrapping a sync method would break it.
+      continue;
+    }
+    const originalMethod = objToDecorate[method];
+    objToDecorate[method] = function() {
+      const args = Array.prototype.slice.call(arguments);
+      const cb = args.slice(-1).pop();
+      const argsWithoutCallback = typeof cb === 'function' ?
+        args.slice(0, args.length - 1) : args;
+      return promiseOrCallback(cb, callback => {
+        return this[`$__${method}`].apply(this,
+          argsWithoutCallback.concat([callback]));
+      }, model.events);
+    };
+    objToDecorate[`$__${method}`] = middleware.
+      createWrapper(method, originalMethod, null, customMethodOptions);
+  }
+}