Analyze requirement

Grant type we are going to use:

1. authorization code grant:

sequenceDiagram
    autonumber
    participant member's
    participant user
    member's->>user: request authorization code https://.../oauth/authorize?response_type=code&client_id=''&redirect_uri=''&state=''&scope=''
    user-->>member's: return a code
    member's->>user: request token http://.../oauth/token?client_id=''&client_secret=''&grant_type=authorization_code&code=''&redirect_uri=''
    user-->>member's: return a token {accessToken,refreshToken}

1. password grant:

sequenceDiagram
    autonumber
    participant member's
    participant user
    member's->>user: request a token https://.../oauth/token?grant_type=password&username=''&password=''&client_id=''
    user-->>member's: return a token

But we could share our data with password grant model