简介
node-red-contrib-mongodb 是一个用于 MongoDB 数据库的 Node-RED 插件，能够简化与 MongoDB 的交互操作。它提供了一系列的节点，让您可以方便地向 MongoDB 数据库插入、查询、更新和删除数据，同时也支持聚合操作和地理位置查询等高级功能。如果您正在进行与 MongoDB 有关的开发工作，那么这个插件将是一个非常有用的工具。
安装
安装 Node-RED
您需要先安装 Node-RED，可以通过以下命令来安装：
sudo npm install -g --unsafe-perm node-red
安装完成后，运行以下命令来启动 Node-RED：
node-red
安装 node-red-contrib-mongodb
在 Node-RED 界面中，点击右上角的 "菜单" 按钮，在 "管理面板" 中选择 "节点"。在 "节点" 页面中，点击 "安装" 选项卡，然后在搜索框中输入 "mongodb"，找到 "node-red-contrib-mongodb" 插件，点击 "安装"，等待安装完成。
安装完成后，在 Node-RED 工作区中将会出现一些与 MongoDB 相关的节点。
使用
使用 node-red-contrib-mongodb 插件可以方便地连接 MongoDB 数据库，并且执行各种操作。下面我们将介绍一些常见的用例。
连接 MongoDB
使用 "mongo-client" 节点来连接 MongoDB 数据库。您需要提供 MongoDB 数据库的连接字符串和数据库名称。如果您需要使用身份验证，也可以提供用户名和密码。
[{"id":"760f1d05.7bdd2","type":"mongo-client","hostname":"localhost","port":"27017","db":"test","name":"MongoDB","max_pool_size":"10","ssl":"false","authSource":""}]插入数据
使用 "insert" 节点来向 MongoDB 数据库插入数据。您需要提供需要插入的数据和要插入到的集合名称。
[{"id":"ace3883c.3f1808","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"John\",\"age\":30}","payloadType":"json","x":140,"y":60,"wires":[["f868d822.0fcfd"]]},{"id":"f868d822.0fcfd","type":"mongodb in","z":"1449f18b.5a5a5e","mongodb":"760f1d05.7bdd2","name":"MongoDB insert","collection":"users","operation":"insert","x":340,"y":60,"wires":[["afc9f9ae.b19458"]]},{"id":"afc9f9ae.b19458","type":"debug","z":"1449f18b.5a5a5e","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":550,"y":60,"wires":[]}]查询数据
使用 "find" 节点来查询 MongoDB 数据库中的数据。您需要提供集合名称和查询条件。查询条件可以是一个 JSON 对象。
[{"id":"b5c5f59a.14e57","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"John\"}","payloadType":"json","x":130,"y":120,"wires":[["f431732b.dce0b8"]]},{"id":"f431732b.dce0b8","type":"mongodb in","z":"1449f18b.5a5a5e","mongodb":"760f1d05.7bdd2","name":"MongoDB find","collection":"users","operation":"find","x":330,"y":120,"wires":[["1dc09d3c.c93fce"]]},{"id":"1dc09d3c.c93fce","type":"debug","z":"1449f18b.5a5a5e","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":530,"y":120,"wires":[]}]更新数据
使用 "update" 节点来更新 MongoDB 数据库中的数据。您需要提供集合名称、查询条件和更新内容。
[{"id":"e4584652.652f8","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"John\"}","payloadType":"json","x":130,"y":180,"wires":[["f2c46775.dc81f8"]]},{"id":"f2c46775.dc81f8","type":"mongodb in","z":"1449f18b.5a5a5e","mongodb":"760f1d05.7bdd2","name":"MongoDB update","collection":"users","operation":"update","x":330,"y":180,"wires":[[]]},{"id":"12579c70.1f81bf","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"Smith\"}","payloadType":"json","x":130,"y":240,"wires":[["f2c46775.dc81f8"]]},{"id":"f5a075f5.58257","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"$set\":{\"age\":40}}","payloadType":"json","x":140,"y":300,"wires":[["f2c46775.dc81f8"]]},{"id":"1f630a2c.24d316","type":"debug","z":"1449f18b.5a5a5e","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":530,"y":180,"wires":[]}]删除数据
使用 "remove" 节点来从 MongoDB 数据库中删除数据。您需要提供集合名称和查询条件。
[{"id":"3b3c42af.332c9e","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"John\"}","payloadType":"json","x":130,"y":360,"wires":[["fbae7465.2d348"]]},{"id":"fbae7465.2d348","type":"mongodb in","z":"1449f18b.5a5a5e","mongodb":"760f1d05.7bdd2","name":"MongoDB remove","collection":"users","operation":"remove","x":330,"y":360,"wires":[[]]},{"id":"c2e326b0.b775d","type":"inject","z":"1449f18b.5a5a5e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"name\":\"John\"}","payloadType":"json","x":130,"y":420,"wires":[["fbae7465.2d348"]]},{"id":"99a12396.77c6f","type":"debug","z":"1449f18b.5a5a5e","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":530,"y":360,"wires":[]}]总结
通过 node-red-contrib-mongodb 插件，我们可以轻松地与 MongoDB 数据库进行交互操作。它提供了诸如插入、查询、更新和删除等功能，让我们能够更加方便地和 MongoDB 进行交互。如果您正在进行相关的开发工作，那么这个插件将会是一个非常有用的工具。
来源：JavaScript中文网 ，转载请注明来源 https://www.javascriptcn.com/post/60066b5451ab1864dac669b8