set up first route 
    - express 
    - router 
    - differt routes
    - module.exports
    - require(./)
    - use

set up first model 
    - mongoose
    - joi
    - jwt 
    - conifg 

    - mongoose schema validation 
    - user input validation 


set up post route 
    user input validate check 
    user existence check 
    save 

set up get route 
    find, select 

hash password: 
    bcrypt 
    salt + hash

jsonwebtoken
    sign with id 
    assign to userSchema.methods
    +
    config 
    +
    export xx=xxx && nodemon index.js

/me 
auth middleware 
    verify token
    return decoded
    next

+bcrypt 
+user model 
+joi

validate 
get user 
compare 
gen and return jwt 

    route
        get / 
        get / id
            - check exitence 

        post /  
            - check user input
            - save

        put /id
            - check user input
            - check existence
                - check linked docs with id 
            - update
            - save

        delete /id
            - find by id 
            - check existence 
            - delete