tasks: addition of MQ publisher class

[dinosk]

• ADD publisher class with reconnection strategy based on https://stackoverflow.com/questions/35193335/how-to-reconnect-to-rabbitmq

Addresses https://github.com/reanahub/reana-workflow-controller/issues/102 Depends on https://github.com/reanahub/reana-workflow-controller/pull/101

[tiborsimko]

Confirmed working with:

• reana-job-controller @ master
• reana-message-broker @ master
• reana-server @ master
• reana-workflow-controller @ pr-101
• reana-workflow-engine-cwl @ master
• reana-workflow-engine-serial @ pr-17
• reana-workflow-engine-yadage @ master
• reana-workflow-monitor @ master

All three workflow engines (CWL Serial, Yadage) report progress well :+1: albeit we should think of updating the messages and the client parsing display:

• serial:

$ reana-client workflow status -w workflow.1
NAME       RUN_NUMBER   CREATED               STATUS     PROGRESS   COMMAND                                                   
workflow   1            2018-06-28T08:56:58   finished   2/2        root -b -q '../code/fitdata.C(\"data.root\",\"plot.png\")'

• cwl:

$ reana-client workflow status -w workflow.2
NAME       RUN_NUMBER   CREATED               STATUS     PROGRESS   COMMAND                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
workflow   2            2018-06-28T08:57:32   finished   2/2        /bin/sh -c 'export PATH="/usr/local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin";export TMPDIR="/data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/tmpdir/_A33Un";export HOME="/data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir";cp -a /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/outdir/w_pMyc/data.root /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir/data.root ;cp -a /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/inputs/fitdata.C /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir/fitdata.C ;mkdir -p /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir && cd /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir && root -b -q '"'"'fitdata.C("data.root","/data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir/plot.png")'"'"'; cp -r /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/docker_outdir/* /data/00000000-0000-0000-0000-000000000000/analyses/291323df-feb5-44ce-a36b-7067e40f80ff/workspace/cwl/outdir/MDga4P' 

• yadage

reana-client workflow status -w workflow.3
NAME       RUN_NUMBER   CREATED               STATUS     PROGRESS   COMMAND                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
workflow   3            2018-06-28T08:57:58   finished   2/2        sh -c 'echo cm9vdCAtYiAtcSAnL2RhdGEvMDAwMDAwMDAtMDAwMC0wMDAwLTAwMDAtMDAwMDAwMDAwMDAwL2FuYWx5c2VzLzAwYThlOWUyLWJkNjktNGFkYy04ZmE3LWIxNzkwZWMwM2E2Ni95YWRhZ2VfaW5wdXRzL2NvZGUvZml0ZGF0YS5DKCIvZGF0YS8wMDAwMDAwMC0wMDAwLTAwMDAtMDAwMC0wMDAwMDAwMDAwMDAvYW5hbHlzZXMvMDBhOGU5ZTItYmQ2OS00YWRjLThmYTctYjE3OTBlYzAzYTY2L3dvcmtzcGFjZS9nZW5kYXRhL2RhdGEucm9vdCIsIi9kYXRhLzAwMDAwMDAwLTAwMDAtMDAwMC0wMDAwLTAwMDAwMDAwMDAwMC9hbmFseXNlcy8wMGE4ZTllMi1iZDY5LTRhZGMtOGZhNy1iMTc5MGVjMDNhNjYvd29ya3NwYWNlL2ZpdGRhdGEvcGxvdC5wbmciKSc=|base64 -d|sh'