* chore: Make `_populate_relayhost_map` easier to grok
Changes to `sed` handling that made it quicker to grok, and thus easier for maintainers like myself:
- Switched regex to [extended regex](https://www.gnu.org/software/sed/manual/html_node/Extended-regexps.html).
- Extracted `sed` patterns to be self-descriptive local vars.
- Used a function to reduce noise from intent of loop input (each line as `DOMAIN_PART`).
Input for the loop is filtered through `sort -u` to drop duplicates, reducing iterations.
`DOMAIN` loop var renamed to less vague `DOMAIN_PART`. Additional comment in the containing method clarifies what the domain part refers to.
---
`|` regexp syntax needed to be escaped due to switch. Not documented in the earlier link. `-r`/`-E` (ERE) aka extended regexp syntax is [detailed here](https://learnbyexample.github.io/learn_gnused/breere-regular-expressions.html#cheatsheet-and-summary).
* chore: Drop unnecessary postfix parameters
`smtp_tls_note_starttls_offer = yes` - Only adds a log entry to let you know when an unencrypted connection was made, but STARTTLS was offered:
https://www.postfix.org/postconf.5.html#smtp_tls_note_starttls_offer
`smtp_tls_CAfile` is unnecessary. This was added before `smtp_tls_CApath = /etc/ssl/certs` was several months later via a separate PR.
* chore: Move `smtp_` parameters to relevant sections
These have been shifted to relevant logic for now.
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NOTE: `SASL_PASSWD` previously needed to define `RELAY_HOST` to set `smtp_sasl_password_maps` to enable the `/etc/postfix/sasl_passwd` table. This change now additionally blocks early on in `_relayhost_sasl`. Not likely important due to `RELAY_HOST` logic, user should be using the `RELAY_USER` + `RELAY_PASSWORD` ENV or `postfix-sasl-password.cf` instead.
Especially the sender dependent parameters which are only relevant with user provided configs really.
`SASL_PASSWD` is the oldest ENV for relay support before any other relay feature arrived. It is poorly documented and should not be used.
Potential breakage risk considered acceptable.
* chore: Revise inline docs
Further clarifying current processing logic and adding some additional notes for future work.
* chore: Use a common ENV relay-host getter
The mapping should be in sync between the two configs.
I also wanted to raise awareness of current state of support, which will likely need some refactoring.
This also removes the need for the `RELAY_PORT` fallback method.
The log message was adjusted as configuration is potentially for more than one relay host beyond the currently required ENV config to enable support.
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NOTE: The ENV `DEFAULT_RELAY_HOST` skips modifying the default transport for an authenticated relay (locked behind `RELAY_HOST` to activate). It presently will only relay mail through a relay host on port 25 instead of delivering directly to the destination. A separate use-case.
* chore: Revise config examples
More verbose example configs with expanded documentation.
Additional doc references for SASL support and cautioning maintainers that may reference popular relay service providers docs. May later be migrated to a "maintainers" section in official docs and link to that.
Brief overview description of what `_populate_relayhost_map` is doing.
* chore: Add notes pertaining to future work
`_populate_relayhost_map` will get some refactoring in future and likely introduce some breaking changes for a future major release.
* chore: Better document relay support inline
This helper now includes a description of it's purpose, links to relevant user docs and supported `setup.sh` commands.
Intent is to keep a maintainer of the feature aware of anything relevant to this feature.
* added new `_log` function
With `_log`, the `_notify` method wa rendered obsolete. `_notify` was
not completely removed due to test failures in `check-for-changes.sh`.
The new `_log` function properly uses log levels such as `trace`,
`debug`, `info`, `warn` and `error`. It provides a cleaner solution
and renders `DMS_DEBUG` obsolete too (as only `_notify` depends on it).
* converted all helper script to new `_log` function
* converted all startup stacks to new `log` function
* `start-mailserver.sh` now uses new `_log` function
* final test and misc small script adjustments
* updated documentation
Removes duplicate logic from `check-for-changes.sh` that is used/maintained elsewhere to avoid risk of problems, as this code is already starting to diverge / rot.
---
Previously the change detection support has had code added for rebuilding config upon change detection which is the same as code run during startup scripts. Unfortunately over time this has fallen out of sync. Mostly the startup scripts would get maintenance and the contributor and reviewers may not have been aware of the duplicate code handled by `check-for-changes.sh`.
That code was starting to diverge in addition to some changes in structure (_eg: relay host logic seems interleaved here vs separated out in startup scripts_). I wanted to address this before it risks becoming a much bigger headache.
Rather than bloat `helper-functions.sh` further, I've added a `helpers/` folder extracting relevant common logic between startup scripts and `changedetector`. If you want to follow that process I've kept scoped commits to make those diffs easier. Some minor changes/improvements were added but nothing significant.
---
- chore: Extract relay host logic to new `relay.sh` helper
- chore: Extract `/etc/postfix/sasl_passwd` logic to new `sasl.sh` helper
- chore: Extract `postfix-accounts.cf` logic to new `accounts.sh` helper
- chore: Extract `/etc/aliases` logic to new `aliases.sh` helper
- chore: Extract `/etc/postfix/vhost` logic to new `postfix.sh` helper
- chore: Add inline docs for Postfix configs
> These are possibly more verbose than needed and can be reduced at a later stage.
> They are helpful during this refactor process while investigating that everything is handled correctly.
`accounts.sh`:
- Add note regarding potential bug for bare domain setups with `/etc/postfix/vhost` and `mydestination` sharing same domain value.
`relay.sh`:
- Remove the tabs for a single space delimiter, revised associated comment.
- Add PR reference for original `_populate_relayhost_map` implementation which has some useful details.
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Co-authored-by: Casper <casperklein@users.noreply.github.com>
