Cleanly reimplement system/edit-config.in. (#13702)

* Cleanly reimplement system/edit-config.in

- Added support for pulling config files from Docker containers.
- Added auto-detection for Docker containers.
- Use directory the script is in for target directory for config files
  instead of templating it in at build time.
- Prefix error messages with `ERROR:`.
- Robustly check for a valid editor _before_ invoking it.
- Add support for actual command-line options, including a proper
  `--help` option.
- Use prefix matching of absolute paths to determine file validity
  instead of blindly excluding certain path types.
- If editing a non-existing file we do not provide a stock copy of,
  create an empty file instead of throwing an error.
- Make the whole script properly modular.

* Improve robustness of container autodetection.

Instead of relying on the lack of certain directories on a host system,
use some relatively standard checks to determine if we appear to be
running in a container.

* Auto-detect stock config paths at runtinme instead of hard-coding them at build time.

THis will simplify testing of the script, as well as making it a bit
more resilient to users moving things around.

* Add an option to list known config files.

* Fix container environment check to not require root.

* Fix help output.

* Fix path prefix check.

* Fix file path handling.

* Use correct variable when editing files.

* Use correct path for `env`.

* Source profile before running `set -e`.

To prevent questionablly written profiles from causing the script to
exit.

* Produce columnar output when listing valid files.

* Fix copy check.

* Fix build issues.

* fix build issues

* formatting

Co-authored-by: ilyam8 <ilya@netdata.cloud>

1 files changed, 6 insertions, 0 deletions

diff --git a/packaging/docker/run.sh b/packaging/docker/run.sh
index 1e001256c2..244f92c421 100755
--- a/packaging/docker/run.sh
+++ b/packaging/docker/run.sh
@@ -49,6 +49,12 @@ if mountpoint -q /etc/netdata && [ -z "$(ls -A /etc/netdata)" ]; then
   cp -a /etc/netdata.stock/. /etc/netdata
 fi
 
+if mountpoint -q /etc/netdata; then
+  hostname > /etc/netdata/.container-hostname
+else
+  rm -f /etc/netdata/.container-hostname
+fi
+
 if [ -n "${NETDATA_CLAIM_URL}" ] && [ -n "${NETDATA_CLAIM_TOKEN}" ] && [ ! -f /var/lib/netdata/cloud.d/claimed_id ]; then
   # shellcheck disable=SC2086
   /usr/sbin/netdata-claim.sh -token="${NETDATA_CLAIM_TOKEN}" \