thin-edge.io: `tedge connect` does not detect mapper/agent via symlinks

Discussed in https://github.com/thin-edge/thin-edge.io/discussions/880

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^{Originally posted by toewsar February 15, 2022} When using tedge connect c8y it tries to find out if the mapper and agent are installed. This is done by the RUST-which(). In my case the binaries aren’t installed at /usr/bin or similar. Therefore the tedge cli does not find the installed mapper and agent.

I tried to create symlinks to /usr/bin to tell tedge that the mapper and agent are installed, but it still failed. The shell command which found the binaries.

$ sudo which tedge_mapper /usr/bin/tedge_mapper

$ sudo tedge connect c8y Checking if sysv is available.

Checking if configuration for requested bridge already exists.

Validating the bridge certificates.

Create the device.

Saving configuration for requested bridge.

Restarting mosquitto service.

Awaiting mosquitto to start. This may take up to 5 seconds.

Enabling mosquitto service on reboots.

Successfully created bridge connection!

Sending packets to check connection. This may take up to 2 seconds.

Connection check is successfull.

Checking if tedge-mapper is installed.

Warning: tedge_mapper is not installed.

Enabling software management.

Checking if tedge-agent is installed.

Info: Software management is not installed. So, skipping enabling related components.

It would be nice to also accept symlinks.</div>