feat: add mongodb storage module

lib/storage/mongodb-storage.js

@@ -0,0 +1,143 @@
+const { MongoClient } = require('mongodb')
+
+/**
+ * @typedef ResourceOptions
+ * @property {String} url url to mongo instance
+ * @property {string} databaseName
+ * @property {string} collectionName
+ */
+
+/**
+ * 
+ * @param {ResourceOptions} param0 
+ * @returns 
+ */
+module.exports = ({ url, databaseName = 'default', collectionName = '_subscriptions' }) => {
+    let mongoDbClient = new MongoClient(url)
+
+    return {
+
+        /**
+         * 
+         * @returns {import('mongodb').MongoClient}
+         */
+        async _getConnectedClient() {
+            if (mongoDbClient?.topology?.isConnected()) {
+                return mongoDbClient
+            } else {
+                return mongoDbClient.connect()
+            }
+        },
+
+        /**
+         * 
+         * @returns {import('mongodb').Collection}
+         */
+        async _getCollection() {
+            const client = await this._getConnectedClient()
+            const db = client.db(databaseName)
+            return db.collection(collectionName)
+        },
+
+        _toStringIfArray(ids) {
+            if (Array.isArray(ids)) {
+                return ids.join('/')
+            } else {
+                return ids
+            }
+        },
+
+        /**
+         * Get a resource by ids
+         * 
+         * @param {Array.<String>} resourceIds resource ids that will added to the resource path i.e. /users/${id}/documents/${id}
+         * @returns 
+         */
+        async get(resourceIds) {
+            const collection = await this._getCollection()
+            return collection.findOne({
+                _id: this._toStringIfArray(resourceIds)
+            })
+        },
+
+        /**
+         * @alias for .get
+         * @param {Array.<String>} resourceIds 
+         * @returns 
+         */
+        async exists(resourceIds) {
+            return this.get(resourceIds)
+        },
+
+        /**
+         * Add a resource to a collection by ids
+         * 
+         * @param {Array.<String>} resourceIds resource ids that will added to the resource path i.e. /users/${id}/documents/${id}
+         * @param {Object} resource the resource to be stored
+         * @returns 
+         */
+        async put(resourceIds, resource) {
+            const exists = await this.exists(resourceIds)
+            if (exists) {
+                throw new Error(`${resourceIds} already exists. ${JSON.stringify(exists)}`)
+            }
+
+            const collection = await this._getCollection()
+            const result = await collection.insertOne(Object.assign(resource, {
+                _id: this._toStringIfArray(resourceIds)
+            }))
+
+            const success = result.acknowledged === true
+            if (!success) {
+                throw new Error(`Was not able to insert ${resourceIds} with resource ${resource}`)
+            }
+        },
+
+        /**
+         * Update a resource by ids
+         * 
+         * @param {Array.<String>} resourceIds resource ids that will added to the resource path i.e. /users/${id}/documents/${id}
+         * @param {Object} update values that should be updated
+         * @returns 
+         */
+        async update(resourceIds, update) {
+            const exists = await this.exists(resourceIds)
+            if (!exists) {
+                throw new Error(`${resourceIds} does not exist.`)
+            }
+
+            const collection = await this._getCollection()
+            const result = await collection.updateOne({
+                _id: this._toStringIfArray(resourceIds)
+            }, update)
+
+            const success = result.acknowledged === true
+            if (!success) {
+                throw new Error(`Was not able to update ${resourceIds} with resource ${update}.`)
+            }
+        },
+
+        /**
+         * Delete a resource by ids
+         * 
+         * @param {Array.<String>} resourceIds resource ids that will added to the resource path i.e. /users/${id}/documents/${id}
+         * @returns 
+         */
+        async delete(resourceIds) {
+            const exists = await this.exists(resourceIds)
+            if (!exists) {
+                throw new Error(`${resourceIds} does not exist.`)
+            }
+
+            const collection = await this._getCollection()
+            const result = await collection.deleteOne({
+                _id: this._toStringIfArray(resourceIds)
+            })
+
+            const success = result.acknowledged === true
+            if (!success) {
+                throw new Error(`Was not able to delete ${resourceIds}.`)
+            }
+        }
+    }
+}