docs: update NEWS, Cargo.toml, debian/changelo for new release

Also, tweak titles in NEWS to be a little shorter.

Sponsored-by: author

1 files changed, 94 insertions, 9 deletions

diff --git a/NEWS b/NEWS
index 927e1a1..4959be1 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,6 @@
-# Release notes for Obnam2, the backup software
+---
+title: Release notes for Obnam2
+...
 
 This file summarizes changes between releases of the second generation
 of Obnam, the backup software. The software is technically called
@@ -6,7 +8,90 @@ of Obnam, the backup software. The software is technically called
 ended in 2017 with version number 1.22.
 
 
-## Obnam2 version 0.3.1, released 2021-03-23
+# Version 0.4.0, released 2021-06-06
+
+## Experimental version
+
+This is an experimental release, and is not meant to be relied on for
+recovery of important data. The purpose of this release is to get new
+features into the hands of intrepid people who want to try out new
+things.
+
+## Breaking changes
+
+This release introduces use of encryption in Subplot. Encryption is
+not optional, and the new `obnam init` command must always be used
+before the first backup to generate an encryption key.
+
+Starting with this version of Obnam, there is no support at all for
+cleartext backups any more. A backup, or backup repository, made with
+a previous version of Obnam **will not work** with this version: you
+can't list backups in a repository, you can't restore a backup, and
+you can't make a new backup. You need to start over from scratch, by
+emptying the server's chunk directory. Eventually, Obnam will stop
+having such breaking, throw-away-everything changes, but it will
+take time to build that functionality.
+
+Note: this version add only a very rudimentary approach to encryption.
+It is only meant to protect the backups from the server operator
+snooping via the server file system. It doesn't protect against most
+other threats, including the server operator replacing parts of
+backups on the server. Future versions of Obnam will add more
+protection.
+
+## New or changed features
+
+* Obnam now by default excludes directories that are marked with a
+  `CACHEDIR.TAG` file. Set `exclude_cache_tag_directories` to `false`
+  in the configuration file to disable the feature. See the [Cache
+  Directory Tagging Specification][] for details of the tag file.
+
+[Cache Directory Tagging Specification]: https://bford.info/cachedir/
+
+* You can now use _tilde notation_ in the configuration file, in fields
+  for specifying backup root directories or the log file. This makes
+  it easier to files relative to the user's home directory:
+
+  ~~~yaml
+  server_url: https://obnam-server
+  roots:
+    - ~/Maildirs
+    ~ ~/src/obnam
+  log: ~/log/obnam.log
+  ~~~
+
+* Alexander Batischev changed the code that queries the SQL database
+  to return an iterator, instead of an array of result. This means
+  that if, for example, a backup generation has a very large number of
+  files, Obnam no longer needs to keep all of them in memory at once.
+
+* Various error messages are now clearer and more useful. For example,
+  if there is a problem reading a file, the name of the file is
+  included in the error message.
+
+## Internal changes
+
+* Alexander Batischev added support for GitLab CI, which means that
+  changes are tested automatically before they are merged. This will
+  make development a little smoother in the future.
+
+
+## Changes to documentation
+
+* Tigran Zakoyan made a logo for Obnam. It is currently only used on
+  the [website](https://obnam.org/), but will find more use later. For
+  example, some stickers could be made.
+
+## Thank you
+
+Several people have helped with this release, with changes or
+feedback. I want to especially mention the following, in order by
+first name, with apologies to anyone I have inadvertently forgotten:
+Alexander Batischev, Daniel Silverstone, Neal Walfield, Tigran
+Zakoyan.
+
+
+# Version 0.3.1, released 2021-03-23
 
 This is a minor release to work around a bug in Subplot, which
 prevented the 0.3.0 release to have a Debian package built. The
@@ -14,15 +99,15 @@ workaround is to rewrite a small table in the "Filenames" section as a
 list.
 
 
-## Obnam2 version 0.3.0, released 2021-03-14
+# Version 0.3.0, released 2021-03-14
 
-### Breaking changes
+## Breaking changes
 
 * The format of the data stored on the backup repository has changed.
   The new version can't restore old backups: old generations are now
   useless. You'll have to start over. Sorry.
 
-### New or changed features
+## New or changed features
 
 * New `obnam config` sub-command writes out the actual configuration
   that the program users, as read from the configuration file.
@@ -57,7 +142,7 @@ list.
 * On the Obnam server, the Ansible playbook now installs a cron job to
   renew the Let's Encrypt TLS certificate.
 
-### Bugs fixed
+## Bugs fixed
 
 * Temporary files created during backup runs are now automatically
   deleted, even if the Obnam client crashes.
@@ -70,7 +155,7 @@ list.
   systemd unit so that the Obnam server process starts automatically
   after a reboot.
 
-### Changes to documentation
+## Changes to documentation
 
 * A tutorial has been added.
 
@@ -91,14 +176,14 @@ improvements:
   started, and then iterate to get something acceptable, even if that
   takes months
 
-### Thank you
+## Thank you
 
 Several people have helped with this release, with changes or
 feedback. I want to especially mention the following, with apologies
 to anyone I have inadvertently forgotten: Alexander Batischev, Ossi
 Herrala, Daniel Silverstone, Neal Walfield.
 
-## Obnam2 version 0.2.2, released 2021-01-29
+# Version 0.2.2, released 2021-01-29
 
 This is the first release of Obnam2. It can just barely make and
 restore backups. It's ready for a light trial, but not for real use.