* add functionality for filtering mail log by ID
This was not planned, but as @polarthene mentioned in
https://github.com/docker-mailserver/docker-mailserver/pull/3033#issuecomment-1407169569
, filtering the mail log by email ID would be (the only) correct
approach for the Rspamd test (to eliminate race conditions).
I asserted the currect state, and came to the conclusion that this might
(or actually is) something we want in more than one place. So I went
ahead and implemented a solution.
The solution for acquiring the ID is a bit slower because it ensures the
mail queue is empty _before_ and _after_ the mail is sent. This is the
tradeoff one has to make if they want to send multiple emails in one
test file and get their IDs.
I hope you like this approach. I will provide another PR that adjusts
our current tests to use these new functions.
* added note about our helper functions in the docs
I think our work for our custom test framework should be noted in the
docs for newcomers to better understand what they should do.
* adjust Rspamd test to use new helpers for sending
* improve filter helpers further
* add sanity check when acquiring mail ID
* re-add `refute_output` to test which should now work well
* added options to toggle OpenDKIM & OpenDMARC
rspamd can provide DKIM signing and DMARC checking itself, so users
should be able to disable OpenDKIM & OpenDMARC. The default is left at
1, so users have to to opt-in when the want to disable the features.
* misc small enhancements
* adjusted start of rspamd
The order of starting redis + rspamd was reversed (now correct) and
rspamd now starts with the correct user.
* adjusted rspamd core configuration
The main configuration was revised. This includes AV configuration as
well as worker/proxy/controller configuration used to control the main
rspamd processes.
The configuration is not tested extensively, but well enough that I am
confident to go forward with it until we declare rspamd support as
stable.
* update & improve the documentation
* add tests
These are some initial tests which test the most basic functionality.
* tests(refactor): Improve consistency and documentation for test helpers (#3012)
* added `ALWAYS_RUN` target `Makefile` recipies (#3013)
This ensures the recipies are always run.
Co-authored-by: georglauterbach <44545919+georglauterbach@users.noreply.github.com>
* adjusted rspamd test to refactored test helper functions
* improve documentation
* apply suggestions from code review (no. 1 by @polarthene)
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
* streamline heredoc (EOM -> EOF)
* adjust rspamd test (remove unnecessary run arguments)
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
* Fix#3007: Changed description of explicit TLS to indicate that insecure connections are rejected
* Further clarification that description only applies to authentication
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
* chore: Drop ENV `ENABLE_POSTFIX_VIRTUAL_TRANSPORT`
* tests(chore): Remove redundant `dovecot-lmtp` config
None of this is needed. Only relevant change is changing the LMTP service listener for Dovecot and that can be delegated to `user-patches.sh`.
* tests(refactor): Use `user-patches.sh` instead of replacing config file
The only relevant changes in `test/config/dovecot-lmtp` regarding LMTP was:
- `/etc/dovecot/dovecot.conf` (`protocols = imap lmtp`) and `/etc/dovecot/protocols.d/` (`protocols = $protocols lmtp`).
- `conf.d/10-master.conf` only changed the LMTP service listener from a unix socket to TCP on port 24 (_this was the only change required for the test to pass_).
None of those configs are required as:
- `protocols = imap pop3 lmtp` [is the upstream default](https://doc.dovecot.org/settings/core/#core_setting-protocols), no need to add `lmtp`.
- The LMTP service listener is now configured for the test with `user-patches.sh`.
* tests(refactor): `mail_lmtp_ip.bats`
- Converted to new testing conventions and common container helpers.
- `ENABLE_POSTFIX_VIRTUAL_TRANSPORT` was not relevant, dropped.
- Revised test cases, logic remains the same.
- Large custom config used was not documented and doesn't appear to serve any purpose. Simplified by replacing with a single modification with `user-patches.sh`.
- Added some additional comments for context of test and improvements that could be made.
* tests(chore): Adjust comments
The comment from `mail_hostname` provides no valid context, it was likely copied over from `tests.bats` in Oct 2020 by accident.
The email sent is just for testing, nothing relevant to LMTP.
---
Added additional comment for test to reference extra information from.
* tests(chore): Update similar log line matching
Extracts out the match pattern and formatting commands into separate vars (reduces horizontal scrolling), and includes extra docs about what the matched line should be expected to look like.
These two links have remained broken for over 6 months. Removing them.
* chore(housekeeping): Broken links
* chore: Remove broken links from `mailserver.env`
* docs: Certbot cloudflare
Add docs for implement certbot-dns-cloudflare to generate certificate for mail server
* Apply suggestions from code review
* fix: certbot-cloudflare docs
Fix the docker-compose command according to the advice
* feat: DNS-Cloudflare certificate renew
Add docs for implementing renewing certificate with crontab
* Apply suggestions from code review
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
`tls.bash` helper was adapted to the new helper scripts location. The `setup.bash` helper saw a bugfix (expanding the array properly) and updates the container default config to configure for IPv4 explicitly.
The IPv4 default was added after recent Docker pushes and I saw weird IPv6 related errors in the logs.. now we're sure IPv4 is the default during tests.
Added functionality to check if a process is running:
- This change adds a helper function to check whether a program is running inside a container or not.
- This added the need for a function like `_run_in_container` but allowing for providing an explicit container name.
- Future PRs can use this helper function now to check whether a process is running or not. This was done for the tests of Fail2Ban, but can be used for other tests in the future as well.
---
chore: Restructured BATS flags in `Makefile`
The `Makefile` has seen a bit of a restructuring when it comes to flags:
1. The `MAKEFLAGS` variables is used by `make`, and allows for adding additional flags that can be used within in recursive calls (via `$(MAKE)`) too, thus DRY approach.
2. The flags for calling BATS were adjusted. `--no-parallelize-within-files` has been added as well to ensure tests _inside_ a single file are run sequentially.
`dms-test` prefix matching changed to expect a `_` suffix as a delimiter.
---
docs: Add a note regarding output from running tests in parallel
As per deprecation notice from v11.3 release notes, and a related prior PR; this ENV is to be removed.
It's no longer considered useful, and none of the tests that configured it were actually using it for relaying anything.
These updates support running tests that have been relocated into `serial` and `parallel/set*` directories.
- `make tests` now calls the two make targets beneath it. The only difference is that `serial` continues the "1 test at a time" approach used prior to this PR, while the `parallel` target increases the `--jobs` arg to run multiple tests concurrently (_configured by `PARALLEL_JOBS`_).
- The `test/%` target leverages Bash syntax magic to ease running single tests without providing the exact path.
- This syntax also supports providing multiple test names (eg: `make test/clamav,template`) to run.
- `**` (globstar) allows for future improvements that can group multiple test files into sub-directories by their scope (eg: anti-spam, ssl, etc).
---
chore: Add `shopt -s globstar` to other targets
I realized that other targets should have this as well in case it is not set.
It is better to be more explicit here than to have weird errors due to `**` not expanding properly.
---
fix(Makefile): Add back `.PHONY` targets
I encountered `make` telling me the target was already up-to-date, which of course is nonsense.
I therefore added back the `.PHONY` targets to ensure tests are always run.
---
docs: Added instructions for running a single test
See https://github.com/docker-mailserver/docker-mailserver/pull/2857/files#r1008582760
* outsourcing env variable setup
This commit contains major parts of the work of refactoring the setup
and usage of environment variables. It outsources the setup into its own
script and provides dedicated functions to be executed at a later point in time.
A **new** env variable was added: `USER_PROVISIONG` which provides a
better way of defining which method / protocol to use when it comes to
setting up users. This way, the `ENABLE_LDAP` variable is deprecated,
but all of this is backwards compatible due to a "compatibility layer", a function provided by the new variables script.
This is not a breaking change. It mostly refators internal scripts. The
only change facing the user-side is the deprecation of `ENABLE_LDAP`. We
can prolong the period of deprecation for this variable as long as we
want, because the new function that ensures backwards compatibility
provides a clean interface for the future.
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
Co-authored-by: Casper <casperklein@users.noreply.github.com>
* chore: Remove `SYS_PTRACE` capability from docs and configs
* chore: Remove `SYS_PTRACE` capability from tests
Doesn't seem to be required. It was originally added when the original change detection feature PR apparently needed it to function.
Dovecot master accounts can now be configured in DMS via `setup.sh`.
A master account is useful for administration purposes, or to perform mailbox backups of every user account over IMAP.
Upstream Docs: https://doc.dovecot.org/configuration_manual/authentication/master_users/
Co-authored-by: Casper <casperklein@users.noreply.github.com>
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
Removed typo "logs".
Removed warning that Docker volumes are strongly recommended, as this can lead new users in the wrong direction (bind mounts are now the default).
Altering line 8, mentioning the default of bind mounts.
* first adjustments to use Fail2Ban with nftables
* replace `iptables` -> `nftables` and adjust tests
nftables lists IPs a bit differently , so the order was adjusted for the
tests to be more flexible.
* line correction in mailserver.env
* change from `.conf` -> `.local` and remove redundant config
* revert HEREDOC to `echo`
Co-authored-by: Casper <casperklein@users.noreply.github.com>
* 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
The new setup will now set env variables on one place and on one place
only. The old setup used two separate places wich is not DRY and
confusing.
Some default values changed:
1. PFLOGSUMM_TRIGGER: logrotate => none
2. REPORT_SENDER: mailserver-report@HOSTNAME => mailserver-report@DOMAIN
3. REPORT_RECIPIENT: "0" => POSTMASTER_ADDRESS
One env variable was renamed: REPORT_INTERVAL => LOGROTATE_INTERVAL
I believe these defaults to be more sensible, especially the REPORT_RECIPIENT
address. The PFLOGSUMM_TRIGGER value was changed to `none` because otherwise
people would start getting daily Postfix log summary reports automatically.
Now, this is opt-in, and reports are sent only when enabled properly.
Some of the variables changed were marked as deprecated. I removed the note,
as the variables now bear some (sane) defaults again for other variables
(i.e.) REPORT_RECIPIENT is now default for other recipient addresses.
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
Co-authored-by: Casper <casperklein@users.noreply.github.com>
* docs(deps): bump mkdocs-material to v8.2.1
* feat(docs): enable mermaid integration
Configuration based on https://squidfunk.github.io/mkdocs-material/reference/diagrams/?h=mermaid#configuration
* fix: allow yaml value mapping
* chore: Adopt mkdocs-material mermaid integration support
Supported by the docs generator now, we no longer need to rely on external image generator or live editor link (both relied on large base64 encoding of mermaid markup). SVG will be rendered by docs now, although a little different style (can be fixed with custom CSS).
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
* follow up on #2383
Fixes a documentation error by which a list would not be rendered
correctly. This has been taken care of.
* update the `README.md`
I felt the need to update the README for several reasons:
1. LDAP issues that the core maintainers team cannot really resolve
2. Cleaning up the somewhat messy structure near the end
The first point goes without explanantion. The second points includes:
2.1. The tagging convention is now easier to read and understand
2.2. Some bullut points or notes have been inlined to "stick" more to
the content that it actually belongs to
2.3. The note about the "old" `setup.sh` for DMS `10.1.0` has been
removed as it is obsolete now. We encourage users to upgrade to
`10.4.0` anyways.
2.4. The markdown code highlighting is now using `CONSOLE` instead of
`BASH` because `CONSOLE` is more appropriate.
2.5. Capitalized headings
2.6. Updated the section about `./setup.sh help` to be in one place now
instead of two
2.7. DKIM key generation does now not interfere with user account
creation.
* adjusted content to PR suggestions
* docs(deps): bump mkdocs-material to 8.0.2
* docs(deps): bump mkdocs-material to 8.0.3
* chore: add default version of docs
* feat: add version warning
* fix: remove version warning
* docs(deps): bump mkdocs-material to 8.0.5
* added code annotation feature
We can introduce new annotation with new PRs in the future. I'd advise against overhauling all code blocks with this feature in this PR - this PR should just introduce the feature.
* docs(deps): bump mkdocs-material to 8.1.0
* fix: remove unnecessary default value
re-add if version warning gets a thing in the future. See https://github.com/docker-mailserver/docker-mailserver/pull/2311#issuecomment-991805830
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Using `set -ex` will exit the script as soon as a non-zero exit code is returned, such as when the docker image fails building the docs due to `build --strict` catching broken links. This also removes the need for `|| exit` when changing directory.
This seems fine for a small script, but AFAIK an alternative fix is just adding `|| exit` to the end of the `docker run` command too? There appears to be advice [against adopting `-e` carelessly](http://mywiki.wooledge.org/BashFAQ/105), while others [encourage `-e`](http://redsymbol.net/articles/unofficial-bash-strict-mode/). I know that several maintainers here have preference towards `set -e` so I've kept the original PR solution.
Additionally:
- `-x` is used to improve command visibility when reviewing the workflow log output.
- `--name` isn't necessary, but was part of the original PR.
- I've chosen not to include `-o pipefail`, only because no pipes are used in this script.
* docs(fix): Fix broken links
* ci(docs): Added inline docs
Extra documentation context for maintainers to quickly grok what's going on.
* chore(docs): Minor typo fix by wernerfred
Added from their related PR by request.
* docs(ssl): Adjust heading levels for provisioning sections
- Group provisioning sections under one heading level.
- Use `attr_list` syntax for headings to make the ToC sidebar entry less verbose.
* docs(ssl): Minor fixes
Typos, formatting.
* docs(ssl): Rephrase Traefik wildcard support
Split the line out into multiple with better phrasing.
* docs(ssl): Add FQDN section
We briefly mention the same info twice on the docs page, but as it applies to all provisioners in general, it's been given it's own detailed section with examples.
Single section to inform users about an FQDN, how it's configured and understood by `docker-mailserver` for both Docker CLI and `docker-compose.yml` variations.
Adds note about wildcard support and bare domains to clear up any confusion configuring FQDN for these two.
Additional note about Certbot using symlinks for it's cert storage.
* chore: Add FQDN comment for `docker-compose.yml` example config
This was a community contributed guide from the Github Wiki prior to docs migration. I've rewritten it by restructuring the content, introducing numerical steps and revising some of the content, while removing third-party software that was unnecessary (the original authors and content related to their use-case, Moodle).
See the PR for further details and reference links regarding the original documents history.
The PR provides improved diff via separate commits scoping changes at the correct change bounds, unfortunately the full diff doesn't align to those boundaries well making it more difficult to review vs individual commits.
Below commit messages are roughly equivalent to what is listed on the PR. The PR provides additional linked resources for reference to support commit message statements.
---
* docs: Add CT log warning
- Added a warning to make users aware that using a public CA like _Let's Encrypt_ will publicly log information that may be somewhat sensitive, or undesirable to have historic records made public which cannot be redacted.
* docs: Revise the manual `certbot` guide
- The `letsencrypt` repo that was linked early in this guide now redirects to the [Certbot repo](https://github.com/certbot/certbot).
- More explicit volume mount instruction for CertBot; the local location was a tad vague.
- Better clarified `/etc/letsencrypt/live` contents structure, as well as FQDN info. Removed the misleading `fqdn:` from `docker-compose.yml` example snippet.
* docs: Revise certbot with Docker guide
- General rewrite of the Docker Certbot section with additional tips (_renewals with automation, and using a alternative CA_).
- Generalized tone and paths in content.
- Update volume mount paths to be consistent with recent normalization effort.
- Moved some instructions into inline-comments for script examples instead.
* docs: Revise Docker with `nginx-proxy` and `acme-companion`
- Break apart into individual steps, indenting content into the step as appropriate.
- Use normalized volume paths (`docker-data/<service>/` prefix).
- `letsencrypt-nginx-proxy-companion` has _changed project name to `acme-companion`_, and _transferred to new maintainers and the `nginx-proxy` organization_. This also affects the DockerHub image references.
- `acme-companion` has _switched from using `simp_le` to `acme.sh`_ for provisioning certificates. This requires mounting an additional volume for persisting provisioner state.
- The dummy container (_webmail_) is no longer `library/nginx`, just [`nginx`](https://hub.docker.com/_/nginx). This container also doesn't appear to be required. I've verified that the ENV can be given to the `mailserver` service container directly. Retained for now.
* docs: Revise Docker Compose with `nginx-proxy` and `acme-companion`
Heavy rewrite of this section. Like the previous commit mentions, this content was outdated. It has been simplified with improved documentation and reference links.
It also looks like there was a mistake in the existing config example as it uses the regular `nginx` image instead of `nginx-proxy`.
- The bulk of the `mailserver` service has been removed, users are advised to have an existing `docker-compose.yml` config for `docker-mailserver` and update only what is relevant to integrate with the cert provisioner.
- `DEBUG` is _false_ by default.
- The `networks:` portion of the example appears to be taken from upstream, _which that has since dropped it_. While we could continue to document this, I consider it more of an advanced config detail that we don't need to touch on in our docs.
- The `htpasswd` volume is unnecessary, only relevant if using _"Basic Authentication"_ to protect access to web service endpoints. `conf.d/` is also not required by default, it can be useful for the `standalone` mode (_documented as a `tip`_). Remaining volumes have inline-comments to document their purpose.
- `volumes_from:` is _not supported in v3 Compose format_, _only v2_ and the Docker CLI. I did not want to advise v2, so I've duplicated the volumes between the two containers instead. Internally `acme-companion` would rely on `volumes_from:` to identify the `nginx-proxy` container, it _provides alternative discovery methods_, the label is outdated and refers the legacy label (_their script logic is the same_); using the ENV `NGINX_PROXY_CONTAINER` seemed most appropriate and has been added.
- Upstream `acme-companion` docs only cover support for v2 Compose format. _There is a note regarding `nginx-proxy`_ having _volumes configured in it's Dockerfile_. Providing a volume for `/etc/nginx/dhparam` is required to avoid creating anonymous volumes each run of `nginx-proxy`. I've used a named data volume here to make it stick out more, it's not desirable and upstream should fix this, then we can drop it.
- I've also opted to only demonstrate the _Two Container (Basic) setup_ that upstream documents. Previously our docs have been showing _`docker-gen` with the Three Container (Advanced) setup_, which allows for not having the Docker API socket attached as a volume to a container exposed to the web. This reduces the security a bit, and I have not mentioned that on our docs. I could caution the reader with a link to upstream about the risk, but I don't think we should maintain the `docker-gen` setup.
* docs(fix): Update anchor links
These mismatched the current section headers they were meant to link to.
"Brief" summary/overview of changes. See the PR discussion or individual commits from the PR for more details.
---
Only applies to the `docs/content/**` content (_and `setup` command_). `target/` and `test/` can be normalized at a later date.
* Normalize to `example.com`
- Domains normalized to `example.com`: `mywebserver.com`, `myserver.tld`, `domain.com`, `domain.tld`, `mydomain.net`, `my-domain.tld`, `my-domain.com`, `example.org`, `whoami.com`.
- Alternative domains normalized to `not-example.com`: `otherdomain.com`, `otherdomain.tld`, `domain2.tld`, `mybackupmx.com`, `whoareyou.org`.
- Email addresses normalized to `admin@example.com` (in `ssl.md`): `foo@bar.com`, `yourcurrentemail@gmail.com`, `email@email.com`, `admin@domain.tld`.
- Email addresses normalized to `external-account@gmail.com`: `bill@gates321boom.com`, `external@gmail.com`, `myemail@gmail.com`, `real-email-address@external-domain.com`.
- **`faq.md`:** A FAQ entry title with `sample.domain.com` changed to `subdomain.example.com`.
- **`mail-fetchmail.md`:** Config examples with FQDNs for `imap`/`pop3` used `example.com` domain for a third-party, changed to `gmail.com` as more familiar third-party/external MTA.
* Normalize config volume path
- Normalizing local config path references to `./docker-data/dms/config/`: `./config/`, `config/`, \``config`\`, `/etc/` (_volume mount src path prefix_).
- Normalize DMS volume paths to `docker-data/dms/mail-{data,state,log}`: `./mail`, `./mail-state` `./data/mail`, `./data/state`, `./data/logs`, `./data/maildata`, `./data/mailstate`, `./data/maillogs`, (_dropped/converted data volumes: `maildata`, `mailstate`_).
- Other docker images also adopt the `docker-data/{service name}/` prefix.
* `ssl.md` - Use `dms/custom-certs` where appropriate.
* Apply normalizations to README and example `docker-compose.yml`
---
Common terms, sometimes interchangeably used or now invalid depending on context: `mail`, `mail container`, `mail server`, `mail-server`, `mailserver`,`docker-mailserver`, `Docker Mailserver`.
Rough transformations applied to most matches (_conditionally, depending on context_):
- 'Docker Mailserver' => '`docker-mailserver`'
- 'mail container' => '`docker-mailserver`' (_optionally retaining ' container'_)
- 'mail server' => 'mail-server' / '`docker-mailserver`'
- 'mail-server' => '`docker-mailserver`'
- 'mailserver' => 'mail-server' / '`docker-mailserver`'
Additionally I checked `docker run` (_plus `exec`, `logs`, etc, sub-commands_) and `docker-compose` commands. Often finding usage of `mail` instead of the expected `mailserver`
Additionally changes `mailserver` hostname in k8s to `mail` to align with other non-k8s examples.
---
* drive-by revisions
Mostly minor revisions or improvements to docs that aren't related to normalization effort.
Initial pass for achieving more consistency with docker-compose related configs.
* Set DMS_DEBUG to 0
* align with default docker-compose.yml
Co-authored-by: Casper <casperklein@users.noreply.github.com>
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
This feature was originally introduced by the PR: https://github.com/docker-mailserver/docker-mailserver/pull/1463
- Assign default DH params to use via Dockerfile build instead of copy and update at runtime.
- Parameterized service names and paths.
- Refactor postfix and dovecot dh methods to wrap shared dh logic
- I don't see any value in checking the alternative service for dh params file to copy over, so that's now dropped too.
- Another conditional check is dropped and the default fallback message for existing DH params file is no longer relevant.
- Improved the remaining `_notify` messages. Collapsing the warning into a single logged message also seemed relevant.
- There is no apparent need for special handling with `ONE_DIR=1`. Dropped it.
- Refactor DH params tests
- Combine custom and default DH param tests into single test file
- docs: Add instructions to use custom DH params
There is no official documented support for custom DH parameters. As no guarantee is provided, this is considered an internal change, not a breaking one.
* docs: Improve FAQ entry for `mail-state` folder
- Links to relevant script logic.
- Better list of services data moved to `mail-state`.
* Update docs/content/faq.md
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
* docs(fix): ONE_DIR env default is now `1`
This was missed during the `ONE_DIR` default change in https://github.com/docker-mailserver/docker-mailserver/pull/2148
* fix relative filepath
* fix: use new URI anchor
Co-authored-by: Casper <casperklein@users.noreply.github.com>
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Decoupling setup process from `setup.sh` script by introducing a setup script _inside_ the container that coordinates the setup process.
**This is not a breaking change**. This way, we do not have to keep track of versions of `setup.sh`.
This change brings the additional benefit for Kubernetes users to be able to make use of `setup` now, without the need for `setup.sh`.
---
* move setup process into container; setup.sh versioning not needed anymore
* add tilde functionality to docs
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
Co-authored-by: Casper <casperklein@users.noreply.github.com>
Centralize the collection of the HOSTNAME and DOMAINAME so that it's predictable and uniform across the various scripts (using the helper). Ensure it supports the various configurations users can have (both subdomain and without subdomain, override and no override).
---
* using _obtain_hostname_and_domainname helper + covers when not a subdomain
doc: OVERRIDE_HOSTNAME takes priority
* added tests for non-subdomain hostname + further improvements
* moved SRS DOMAINANME tests into hostname test file + Allowing DOMAINNAME ENV to override what would be automatically set
---
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Adds a new blog post that covers setting up docker-mailserver on a VPS, including but not limited to
* Considerations when selecting a VPS
* Initial configuration of docker-mailserver
* DNS setup and verification of settings
* Multiple domains
Co-authored-by: Frederic Werner <20406381+wernerfred@users.noreply.github.com>
