Gatt Server not offering Services

[Severon96]

Hey guys,

can someone help me please, because i'm a little confused why i'm not seeing any services when using a BTLE Scanner?

I used the GATT-Server implementation that is documented here:
https://docs.rs/bluer/latest/src/gatt_server_io/gatt_server_io.rs.html

I changed nothing, also i'm using the UUIDs from the gatt.inc.
Maybe someone can help me here? Because I don't know what the problem is.

I fixed the initial issue, that I had, by using the UUIDs from the examples. But I'm certain that that's not the right way to work with the crate.

[surban]

Does the corresponding GATT client example work, when used together with the GATT server example?

What BlueZ version are you using?

[Severon96]

Nope, I don't get the examples working. They're always failing with this Error:

thread 'main' panicked at 'services: Os { code: 2, kind: NotFound, message: "No such file or directory" }', bluer/build.rs:256:6

My BlueZ version is: 5.43-2+rpt2+deb9u2

[surban]

Please make sure you cloned the repository with submodules as described in the README.

[Severon96]

I've forgot the --recursive flag when checking out, that's correct. But nevertheless I added it when checking out again I still receive the "NotFound" error when running the example. But now without any message.

pi@raspberrypi:~/bluer/bluer $ cargo run --all-features --example gatt_server_io   Compiling tokio v1.20.1
   Compiling dbus v0.9.6
   Compiling dbus-crossroads v0.5.1
   Compiling dbus-tokio v0.7.5
   Compiling tokio-stream v0.1.9
   Compiling bluer v0.15.0 (/home/pi/bluer/bluer)
    Finished dev [unoptimized + debuginfo] target(s) in 6m 39s
     Running `/home/pi/bluer/target/debug/examples/gatt_server_io`
Error: Error { kind: NotFound, message: "" }

Regarding your question for my BlueZ version:
I tried another command to fetch the version today and received 5.50 as output. I don't know why it's different, when I use another command (bluetoothd -v this time), but I thought it may help you to know that.

[surban]

Could you run bluetoothctl and verify that an adapter is present?

[Severon96]

The adapter wasn't present, I fixed that now. But I now get another error when trying to launch the example:

pi@raspberrypi:~/bluer $ cargo run --all-features --example gatt_server_io
    Finished dev [unoptimized + debuginfo] target(s) in 1.73s
     Running `target/debug/examples/gatt_server_io`
Error: Error { kind: Internal(DBus("org.freedesktop.DBus.Error.AccessDenied")), message: "Rejected send message, 2 matched rules; type=\"method_call\", sender=\":1.9\" (uid=1000 pid=2927 comm=\"target/debug/examples/gatt_server_io \") interface=\"org.freedesktop.DBus.ObjectManager\" member=\"GetManagedObjects\" error name=\"(unset)\" requested_reply=\"0\" destination=\"org.bluez\" (uid=0 pid=459 comm=\"/usr/local/libexec/bluetooth/bluetoothd --experime\")" }

I made the experience that if I build my code and run the compiled version with sudo this error is fixed. But that doesn't work for the example because it throws an "NotRegistered"-Error for me then.

[surban]

Please update BlueZ to at least version 5.60.

[Severon96]

So, sorry that you didn't hear anything from me in the past days. The update of BlueZ didn't work very well on my old image with Raspbian Stretch running on it.
I've created a new image now and updated to 5.65.
Now the gatt_server_io example is starting and I can search with some bluetooth-tools for it. Also my code is working, too (not wondering, since it's nearly an exact copy of the example, but Hey. Worth mentioning!).
Thanks for your help!

[surban]

Great to hear it's working now!