[Pkg-salt-team] Bug#894245: src:salt: cannot install master nor minion due to tornado & zmq breakage

[Vincas Dargis]

Package: src:salt
Version: 2017.7.4+dfsg1-1
Severity: important

Dear Maintainer,

It seems that due to #893360 salt-master and salt-minion cannot be
installed.

salt-master depends on python3-zmq, meanwhile salt-common depends on python3-tornado.

Since tornado breaks zmq (as in bug mentioned before), it's not possible to
install nor master neither minion:

```
$ sudo aptitude install salt-master
The following NEW packages will be installed:
  python3-croniter{a} python3-crypto{a} python3-dateutil{a} python3-jinja2{a}
  python3-markupsafe{a} python3-msgpack{a} python3-psutil{a} 
    python3-pygit2{a} python3-systemd{a} python3-tornado{ab} python3-tz{a}
    python3-yaml{a} python3-zmq{a} salt-common{a} salt-master 
    0 packages upgraded, 15 newly installed, 0 to remove and 0 not upgraded.
    Need to get 4.559 kB of archives. After unpacking 29,8 MB will be used.
    The following packages have unmet dependencies:
     python3-tornado : Breaks: python3-zmq (< 17) but 16.0.2-2+b1 is to be
     installed
     The following actions will resolve these dependencies:

          Keep the following packages at their current version:
          1)     python3-zmq [Not Installed]                        
          2)     salt-master [Not Installed] 
```

```
$ sudo aptitude install salt-minion
The following NEW packages will be installed:
  dctrl-tools{a} python3-croniter{a} python3-crypto{a} python3-dateutil{a}
  python3-jinja2{a} python3-markupsafe{a} python3-msgpack{a} python3-psutil{a} 
    python3-systemd{a} python3-tornado{ab} python3-tz{a} python3-yaml{a}
    python3-zmq{a} salt-common{a} salt-minion 
    0 packages upgraded, 15 newly installed, 0 to remove and 0 not upgraded.
    Need to get 4.540 kB of archives. After unpacking 29,7 MB will be used.
    The following packages have unmet dependencies:
     python3-tornado : Breaks: python3-zmq (< 17) but 16.0.2-2+b1 is to be
     installed
     The following actions will resolve these dependencies:

          Keep the following packages at their current version:
          1)     python3-zmq [Not Installed]                        
          2)     salt-minion [Not Installed] 
```

Is it neccessary for salt-common to depend on tornado if both master and minion
uses zmq?



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