Command line to install mongoDB on Ubuntu
sudo apt-get install gnupg wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add - echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list sudo apt-get update sudo apt-get install -y mongodb-org sudo systemctl start mongod sudo systemctl enable mongod
Mongodb is easy to install, but it could also conflicts and stop working sometimes which is annoying, the best approach to solve this issue would be to always use it with docker like this:
mkdir ~/data sudo docker run -d -p 27017:27017 -v ~/data:/data/db mongo
sudo systemctl enable mongod
Rather than using methods chain and callback, from express router we can call to mongoose findOne using async await as following
we can then search for mongo, if found then use the object, not found then create new one and attach to the second entity.
// mongoose.model("Child", ChildSchema);
// mongoose.model("Parent", ParentSchema);
router.post('/create', async function (req, res, next) {
const user = req.user;
const childObject = req.body.object1;
const parentObject = req.body.object2;
console.log('create parent-child for user: ', user, ' from parent: ', parentObject, 'to child:', childObject);
var parentEntity = await Parent.findOne({criteria1: parent.value1}).exec();
if(!parentEntity) {
parentEntity = new Parent(parentObject);
parentEntity.extra = 'extra';
parentEntity.userId = user.id;
parentEntity.save();
}
var childEntity = await Child.findOne({criteria1: child.value1}).exec();
if(!childEntity) {
childEntity = new Child(child);
childEntity.extra = 'extra';
childEntity.userId = user.id;
childEntity.parentId = parentEntity.id;
childEntity.save();
}
});This helps us solve the express mongoose mongodb object dependency issue
wget https://downloads.mongodb.com/compass/mongodb-compass-1.22.1.x86_64.rpm sudo dnf install ./mongodb-compass-1.22.1.x86_64.rpm
sudo vi /etc/yum.repos.d/mongodb.repo
[Mongodb]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/amazon/2/mongodb-org/4.2/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-4.2.asc
sudo dnf update
sudo dnf install mongodb-org
sudo systemctl enable mongod.service
sudo systemctl start mongod.service
mongod --version
mongo
> use test;
switched to db test
> db.test.save({'hello':'world'})
WriteResult({ "nInserted" : 1 })
> db.test.find()
{ "_id" : ObjectId("5f82b166af5d9be8c5bd0449"), "hello" : "world" }
>
sudo apt-get install gnupg wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add - echo "deb http://repo.mongodb.org/apt/debian buster/mongodb-org/4.4 main" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list sudo apt-get update sudo apt-get install -y mongodb-org sudo systemctl daemon-reload sudo systemctl start mongod sudo systemctl status mongod sudo systemctl enable mongod sudo systemctl stop mongod sudo systemctl restart mongod