Add new sensors listing feature

[DL6ER]

What does this implement/fix?

Adds a new CLI feature useful for debugging sensor issues. We should add it to pihole -d as well.

Example output:

$ pihole-FTL --sensors

{
        "list": [{
                        "name": "nct6793",                                                                                                                                                    
                        "path": "hwmon2",                                                                                                                                                     
                        "source":       "devices/platform/nct6775.656",                                                                                                                       
                        "temps":        [{                                                                                                                                                    
                                        "name": "AUXTIN3",                                                                                                                                    
                                        "value":        104,                                                                                                                                  
                                        "max":  null,                                                                                                                                         
                                        "crit": null,                                                                                                                                         
                                        "sensor":       "temp6"                                                                                                                               
                                }, {                                                                                                                                                          
                                        "name": "AUXTIN0",                                                                                                                                    
                                        "value":        45,                                                                                                                                   
                                        "max":  0,                                                                                                                                            
                                        "crit": null,                                                                                                                                         
                                        "sensor":       "temp3"                                                                                                                               
                                }, {                                                                                                                                                          
                                        "name": "SMBUSMASTER 0",                                                                                                                              
                                        "value":        46.5,                                                                                                                                 
                                        "max":  null,                                                                                                                                         
                                        "crit": null,                                                                                                                                         
                                        "sensor":       "temp7"                                                                                                                               
                                }, {                                                                                                                                                          
                                        "name": "AUXTIN1",                                                                                                                                    
                                        "value":        109,                                                                                                                                  
                                        "max":  null,                                                                                                                                         
                                        "crit": null,                                                                                                                                         
                                        "sensor":       "temp4"                                                                                                                               
                                }, {
                                        "name": "SYSTIN",
                                        "value":        114.5,                                                                                                                                
                                        "max":  null,                                                                                                                                         
                                        "crit": null,                                                                                                                                         
                                        "sensor":       "temp1"
                                }, {                                                           
                                        "name": "AUXTIN2",
                                        "value":        107,
                                        "max":  null,         
                                        "crit": null,
                                        "sensor":       "temp5"
                                }, {                                                           
                                        "name": "CPUTIN",
                                        "value":        46,
                                        "max":  80,
                                        "crit": null,
                                        "sensor":       "temp2"                        
                                }]        
                }, {                                                                           
                        "name": "nvme",                                                        
                        "path": "hwmon0",                                                      
                        "source":       "devices/pci0000:00/0000:00:02.4/0000:04:00.0/nvme/nvme0",
                        "temps":        [{                                                     
                                        "name": "Composite",
                                        "value":        41.85,
                                        "max":  117.85,
                                        "crit": 149.85,
                                        "sensor":       "temp1"
                                }]
                }, {
                        "name": "k10temp",
                        "path": "hwmon3",
                        "source":       "devices/pci0000:00/0000:00:18.3",
                        "temps":        [{
                                        "name": "Tctl",
                                        "value":        46.25,
                                        "max":  null,
                                        "crit": null,
                                        "sensor":       "temp1"
                                }]
                }, {
                        "name": "amdgpu",
                        "path": "hwmon1",
                        "source":       "devices/pci0000:00/0000:00:08.1/0000:05:00.0",
                        "temps":        [{
                                        "name": "edge",
                                        "value":        43,
                                        "max":  null,
                                        "crit": null,
                                        "sensor":       "temp1"
                                }]
                }],
        "cpu_temp":     46.25,
        "hot_limit":    0,
        "unit": "C"
}

Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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[yubiuser]

I was wondering, instead of having a fixed new cli option for a specific endpoint, could we bake a http client into FTL only allowing to query itself. This would offer all GET endpoints to be easily accessible from cli.

E.g.
pihole-FTL --api '/info/sensors'
pihole-FTL --api '/stats/summary'

[rdwebdesign]

We should add it to pihole -d as well.

Follow-up PR: pi-hole/pi-hole#5735

[DL6ER]

could we bake a http client into FTL

In theory yes, but I'm afraid it is some deep rabbit hole. CIvetweb has some very basic HTTP client but...

1. It is still an HTTP connection via a socket, the server cannot reliably determine that this is an internal connection -> we need to authenticate. Even when CLI password is enabled, the normal user does probably have access to the CLI password unless they manually tweaked permissions/group ownership.
2. HTTPS is not possible with CivetWeb so the implementation would only work when there is at least one HTTP port.

It's probably easier to implement something like this in the pihole CLI command which can then utilize curl which is able to handle HTTPS and all the other things as well. We also already have the authentication code readily available in core.

[DL6ER]

See pi-hole/pi-hole#5736

I'm still not sure if this supersedes this particular PR. The reason being that the pihole api feature may require the users to log in (as said above) which is probably not working very well when used in pihole -d.

[yubiuser]

I think pi-hole/pi-hole#5736 supersedes this PR. It's way more generic and can be very helpful during supporting on discourse.

We should add it to pihole -d as well.

I don't think this is the case. Having issues with the senor data is very rar and we tried to keep pihole -d lean to handle the output (and to reduce the data we collect by default). With pi-hole/pi-hole#5736 the information is available very easily and can be asked by supporting staff if needed.