Understanding UserModel

You should see two new files:

$ cd ~/workspace/loopback-zero-to-hero  
$ tree common -L 3
common
└── models
    ├── user-model.js
    └── user-model.json

1 directory, 2 files

Take note of the following: a) user-model.json has the following lines:

  "name": "UserModel",
  "base": "User",

b) the files are named user-model.js and user-model.json but the internal name used by code is UserModel, this is part of loopback's naming convention.

c) user-model.json serves as a configurable entry point whereas user-model.js lets you add code when something more specialized may be required, something that can't be simply configured.

d) Moving forward we will always use UserModel so we can and should hide the User model from the prying eyes of our REST~ful api.

e) The server/model-config.json file is the gatekeeper for what's exposed over REST and what's not.

cat ~/workspace/loopback-zero-to-hero/server/model-config.json
{
  ...
  "User": {
    "dataSource": "db"
  },
  ...
  "UserModel": {
    "dataSource": "db",
    "public": true
  }
}

f) Go ahead and set "public": false for User in model-config.json file:

{
  ...
  "User": {
    "dataSource": "db",
    "public": false
  },
  ...
}

g) Fire up the server:

$ cd ~/workspace/loopback-zero-to-hero
$ node .
Browse your REST API at http://0.0.0.0:3000/explorer
Web server listening at: http://0.0.0.0:3000/

h) Project > Box Info

i) Open a browser window: http://<box-name>.codio.io:3000/explorer/

j) The UserModel api will be ready to explore and User will be no more!

k) Use /POST UserModels from the explorer UI to create a user:

    {
      "username": "test",
      "password": "test",
      "email": "[e-mail]"
    }

Use that as the json body and then click the `Try it out!` button.

l) There is a distinct possiblility that your server will crash at this point with `TypeError: Object.keys called on non-object`

Here's the full sample stack trace:

events.js:72 throw er; // Unhandled 'error' event ^ TypeError: Object.keys called on non-object at Function.keys (native) at Memory.all (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/connectors/memory.js:315:22) at /home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/dao.js:1453:19 at doNotify (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:93:49) at doNotify (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:93:49) at doNotify (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:93:49) at doNotify (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:93:49) at doNotify (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:93:49) at Function.ObserverMixin._notifyBaseObservers (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:116:5) at Function.ObserverMixin.notifyObserversOf (/home/codio/workspace/loopback-zero-to-hero/node_modules/loopback-datasource-juggler/lib/observer.js:91:8)

|||guidance
# Guidance

If this happens, simply delete the previous `db.json` file:
`rm ~/workspace/loopback-zero-to-hero/db.json `
And start the server again, then Follow steps (g) through (k) again.
|||

m) Take a peek at the database, it should have a new UserModel instance: `cat db.json`

$ cat db.json { "ids": { "User": 1, "AccessToken": 1, "ACL": 1, "RoleMapping": 1, "Role": 1, "UserModel": 2 }, "models": { "User": {}, "AccessToken": {}, "ACL": {}, "RoleMapping": {}, "Role": {}, "UserModel": { "1": "{\"username\":\"test\",\"password\":\"$2a$10$DD6l9hEK0YraAvQ9wxXoyujLyted4YUUOUX9opiTUe8RwPOGe8mY2\",\"email\":\"[e-mail]\",\"id\":1}" } } }

```