feat: add postgresql classifier

[witchcraze]

This PR adds a binary cataloger for postgresql

• make some test files by echo -en '\x00{version}'
• update httpd package version for integration test

fixes #1456

[witchcraze]

local integration results

=== RUN   TestPackageDeduplication
=== RUN   TestPackageDeduplication/AllLayers
=== RUN   TestPackageDeduplication/Squashed
--- PASS: TestPackageDeduplication (22.60s)
    --- PASS: TestPackageDeduplication/AllLayers (16.65s)
    --- PASS: TestPackageDeduplication/Squashed (5.95s)

[wagoodman]

I'm seeing the tests fail locally in the same way that is failing in CI. I'm not certain why you are seeing anything different... what os/arch are you running this from? And have you tried purging the image cache ( rm test/integration/test-fixtures/cache/stereoscope-fixture-image-vertical-package-dups-*) and fixture image from docker (docker images | grep image-vertical-package-dups then docker rmi the entries) and re-running? We want to make the tests as stable as possible so I'm curious for how that goes.

In the meantime I reverted the integration test change.

[witchcraze]

@wagoodman

Thank you for your support.

what os/arch are you running this from?

Platform : WSL2
OS : Debian11
arch : x86_64
Go : 1.19

$ uname -a
Linux e14 5.15.79.1-microsoft-standard-WSL2 #1 SMP Wed Nov 23 01:01:46 UTC 2022 x86_64 GNU/Linux
$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
$ go version
go version go1.19 linux/amd64

have you tried purging the image cache ...

Now, I did below.
From message, 2.4.6-98.el7.centos.6 seemes installed.

$ rm test/integration/test-fixtures/cache/stereoscope-fixture-image-vertical-package-dups-*
$ docker image rm -f $(docker images -q)
$ make clean
$ make bootstrap
$ make unit
:
:
Coverage: 68.0%
$ make integration
:
:
================================================================================
 Package           Arch        Version                       Repository    Size
================================================================================
Installing:
 httpd             x86_64      2.4.6-98.el7.centos.6         updates      2.7 M
Installing for dependencies:
 apr               x86_64      1.4.8-7.el7                   base         104 k
 apr-util          x86_64      1.5.2-6.el7                   base          92 k
 centos-logos      noarch      70.0.6-3.el7.centos           base          21 M
 httpd-tools       x86_64      2.4.6-98.el7.centos.6         updates       94 k
 mailcap           noarch      2.1.41-2.el7                  base          31 k

Transaction Summary
================================================================================
:
ok      github.com/anchore/syft/test/integration        534.328s

In my environment, centos:7.9.2009 provides 2.4.6-98.el7.centos.6, not 2.4.6-97.el7.centos.5
From CentOS Mirror, 2.4.6-98.el7.centos.6 was from 2023-01-27 18:02.

$ docker run -it --rm centos:7.9.2009 yum --showduplicates list | grep '^httpd.x86_64'
httpd.x86_64                              2.4.6-95.el7.centos            base
httpd.x86_64                              2.4.6-97.el7.centos            updates
httpd.x86_64                              2.4.6-97.el7.centos.1          updates
httpd.x86_64                              2.4.6-97.el7.centos.2          updates
httpd.x86_64                              2.4.6-97.el7.centos.4          updates
httpd.x86_64                              2.4.6-97.el7.centos.5          updates
httpd.x86_64                              2.4.6-98.el7.centos.6          updates

We want to make the tests as stable as possible so I'm curious for how that goes.

I'll try to fix versions in
https://github.com/anchore/syft/blob/main/test/integration/test-fixtures/image-vertical-package-dups/Dockerfile