`tmlatestbackup`
=================
*Really simple CLI app to obtain the date of the last Mac OS Time Machine backup.*
## Install
The recommended installation option is use Homebrew with the command:
```sh
brew install bglezseoane/tap/tmlatestbackup
```
You can only install the program with Cargo, with the command:
```sh
cargo install tmlatestbackup
```
## Use
The normal use of the tool is very simple. You only need to run:
```sh
tmlatestbackup
```
And obtain the date of the last Time Machine backup with format like: `2018-11-21-102312`.
### Achieve permissions against Mac OS System Integrity Protection
If your current **terminal app** has **full disk access** and you use `tmlatestbackup` **since it**, the tool will works fine. If you only want to work with `tmlatestbackup` **since your terminal** or since scripts used by you since your terminal, **the above is sufficient** and the following steps are irrelevant to your use case.
Otherwise, if you want to use the tool since an script routine as **`launchd` agent**, the tool is going to fail due to System Integrity Protection.
Mac OS System Integrity Protection block `tmlatestbackup` because the tool try to access protected Time Machine features and it doesn't inherit permissions —**using it since the terminal, inherit terminal granted ones**—. To achieve permissions, you need to grant them adding the binary (`/usr/local/bin/tmlatestbackup`) to the list of applications with full disk access —System Preferences > Security & Privacy > Full Disk Access > Add—.
The path `/usr/local/bin/tmlatestbackup` could be different if you have installed with Cargo. Any case, you can check it with `which tmlatestbackup`.
If your agent only needs to run the tool and no more stuff, you can add the following lines to the agent `Info.plist` and it will work (after previously indicated step):
```xml
ProgramArguments
/usr/local/bin/tmlatestbackup
```
For any reason, to work with the tool since the `launchd` agent and **integrated in a shell script**, you need to always run it as `open -a '/usr/local/bin/tmlatestbackup'` and not directly as a command (e.g. `/usr/local/bin/tmlatestbackup`). I.e., if you use, e.g., the following agent specification...
```xml
ProgramArguments
/Users/You/scripts/script_which_calls_tmlatestbackup.sh
```
... you need to run `tmlatestbackup` as follows:
```sh
# 'script_which_calls_tmlatestbackup.sh'
# ...
open -a '/usr/local/bin/tmlatestbackup'
# And not '/usr/local/bin/tmlatestbackup
# ...
```
When run with `open -a`, the command don't return an error code if the launched application fails, so in order to integrate this step in a well designed script, the next approach is recommended:
```sh
# ...
# Create temporary file to save the output of the 'open' command
TMP_OPEN_TMLATESTBACKUP_STDOUT=$(mktemp -t open_tmlatestbackup)
# Run and wait
open -W -a '/usr/local/bin/tmlatestbackup' \
--stdout "$TMP_OPEN_TMLATESTBACKUP_STDOUT" \
--stderr "$TMP_OPEN_TMLATESTBACKUP_STDOUT"
# Check and act attending to the process success
if ! [[ "$(cat "$TMP_OPEN_TMLATESTBACKUP_STDOUT")" \
=~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}-[0-9]{6}$ ]]
then
>&2 echo "Error using 'tmlatestbackup'."
rm "$TMP_OPEN_TMLATESTBACKUP_STDOUT"
exit 1
fi
# Clean
rm "$TMP_OPEN_TMLATESTBACKUP_STDOUT"
# ...
```
## Motivation
On my Mac OS machine I have some scripts that cannot work as agents because it is prevented by System Integrity Protection, which only allows granting permissions to binary programs. That, coupled with the fact that I wanted to learn the Rust language, motivated me to write this simple program in order to have the conflicting step in a compiled program to authorize it and can maintain my script routine working elegantly —and not with pseudo-compiled shell scripts inserted in a compiled language program—. However, at the end of the day `tmlatestbackup` is a potentially useful generic purpose program.