# 30.09.2021 // Config Docs

BFFH uses [DHALL](https://dhall-lang.org/) for Config-File structure
BFFH uses [RBAC](https://en.wikipedia.org/wiki/Role-based_access_control) for access control

## General BFFH Config
General BFFH Config is in `bffh.dhall` file.

#### `listens`
Contains the Addresses BFFH is listen for Connection for the API
Default Port for BFFH is `59661`

**Example:**
```
listens = 
[ 
    { address = "127.0.0.1", port = Some 59661 }
]
```

#### `mqtt_url`
Contains the Address for the MQTT Server BFFH connects to
**Example:**
```
mqtt_url = "tcp://localhost:1883" 
```

#### `db_path`
Contains the Path for the internal Database BFFH uses.
BFFH will create two files: `<db_path>` and `<db_path>-lock`.
Make sure that BFFH has write access in the relevant directory
**Example:**
```
db_path = "/tmp/bffh"
```

Permissions
---
BFFH uses a Path-style string as permission format, separated by ".".
So for example `this.is.a.permission` consists of the parts `this`, `is`, `a` and `permission`.
When requireing permissions, such as in machines you always need to give an exact permission, so for example `test.write`.
When granting permissions, such as in roles you can either give an exact permission or you can use the two wildcards `*` and `+`.
These wildcards behave similar to regex or bash wildcards:
- `*` grants all permissions in that subtree.
  So, `perms.read.*` will match for any of:
  - `perms.read`
  - `perms.read.machineA`
  - `perms.read.machineB`
  - `perms.read.machineC.manage`
- `+` grants all permissions below that one.
  So, `perms.read.+` will match for any of:
  - `perms.read.machineA`
  - `perms.read.machineB`
  - `perms.read.machineC.manage`
  - **but not** `perms.read`

Wildcards are probably most useful if you group you machines around them, e.g. your 3D-printers and your one bandsaw require:

1. Write permissions
    - `machines.printers.write.prusa.sl1`
    - `machines.printers.write.prusa.i3`
    - `machines.printers.write.anycubic`
    - `machines.bandsaws.write.bandsaw1`
1. Manage permissions
    - `machines.printers.manage.prusa.sl1`
    - `machines.printers.manage.prusa.i3`
    - `machines.printers.manage.anycubic`
    - `machines.bandsaws.manage.bandsaw1`
1. Admin permissions
    - `machines.printers`
        * For all printers
    - `machines.bandsaws`
        * For all bandsaws

And you then give roles permissions like so:

* Use any 3D printer:
    * `machines.printers.write.+`
* Only allow use of the "cheap" printers
    * `machines.printers.write.anycubic.*`
    * `machines.printers.write.prusa.i3`
* Allow managing of printers:
    * `machines.printers.+`
* Allow administrating printers:
    * `machines.printers.*`

This way if you buy a different anycubic and split the permissions to e.g.

- `machines.printers.write.anycubic.i3`
- `machines.printers.write.anycubic.megax`

It still works out.


Machine Config
---
Machine Config is in ```machine.dhall``` file.

#### `machines`
Contains list of machines

Machines have different perission levels to interact with:
* disclose: User can see the machine in machine list
* read: User can read information about the machine and there state
* write: User can use the machine
* manage: User can interact with the machine as Manager (Check, ForceFree, ForceTransfer)

**Example:**
```
machines = 
{ 
    Testmachine = 
    { 
        name = "Testmachine",
        description = Some "A test machine",
        disclose = "lab.test.read",
        read = "lab.test.read",
        write = "lab.test.write",
        manage = "lab.test.admin"
    }
}
```

Roles Config
---
Roles Config is in `roles.dhall` file.

#### `roles`
Contains list of roles

Roles have a list of permission and can be inherited.
Permission can be wildcard in permission list.

**Example:**
```
roles =
{
    testrole = 
    {
        permissions = [ "lab.test.*" ]
    },
    somerole =
    { 
        parents = ["testparent"],
        permissions = [ "lab.some.admin" ]
    }, 
    testparent =
    {
        permissions =
        [
            "lab.some.write",
            "lab.some.read",
            "lab.some.disclose"
        ]
    }
}
```

Actors Config
---
Actors Config is in `actors.dhall` file.

#### `actors`
Contains list of actors
Actors are defined by a module and one or more paramters

Currenty supported actors:
**`Shelly`**
Parameters:
`id` = ID of the Shelly

**`Process`**
Parameters:
`cmd` = Path of executable
`args` = Arguments for executable

**Example:**
```
actors = 
{
    Shelly_1234 = { module = "Shelly", params = 
    {
        id = "12345"
    }},
    Bash = { module = "Process", params =
    { 
        cmd = "./examples/actor.sh",
        args = "your ad could be here"
    }}
}
```

#### `actor_connections`
Connects the actor with a machine
A machine can have multiple actors
**Example:**
```
actor_connections = 
[
    { _1 = "Testmachine", _2 = "Shelly_1234" },
    { _1 = "Another", _2 = "Bash" },
    { _1 = "Yetmore", _2 = "Bash2" }
]
```