job-new.sh #4

#!/bin/bash

VERSION=1.2.0

#------------------------------------------------------------------------------
# job-new.sh
#
# This script simplifies the process of using "named" jobs with a Perforce
# server.  A "named" job is one that does not use Perforce's built-in job
# numbering mechanism, which simply names jobs 'job######', incrementing the
# numeric value.
#
# The idea of job-new.sh is that you can name your jobs something more
# meaningful, like MyProj-3, ACME-15, or even ACME-15-3 (where the latter
# implies that ACME-15-3 is a subtask of ACME-15).  By default with
# Perforce, jobs named anything other than the default must be manually
# named and incremented.  With this trigger, you simply name your job
# something like "PRJ-new", and the "-new" suffix is replaced with the
# next available number.  So the first time you create a job with
# "Job: PRJ-new", it will be saved as PRJ-1.  The next time it will be
# PRJ-2.
#
# This is vaguely like what Perforce does by default when you simply use
# "Job: new", except that this numbering scheme does not use left-padding
# of zeros, and the built-in prefix of "job" is not used.
#
# This trigger script is not appropriate to use if Perforce is
# integrated with a defect tracker such as JIRA for Bugzilla.  With such
# systems, Perforce jobs mirror issue names from the defect tracker.
#
# This script must be enabled as a trigger by the Perforce server, with
# an entry like the following needed in the Triggers table.
# Triggers:
#   JobName form-in job "/path/to/job-new.sh %formfile%"
#
# This script also performs some rudimentary job name vetting, to be
# sure the name is in lin with Workshop standards.
# Per Thomas Gray:
#
# If no Project is specified, and the job name is "new", then job creation should succeed as normal.
# If no Project is specified, and any name other than 'new' is specified, job creation should fail.  
# If a Project id is specified, but that Project has no stored prefix, job creation should fail if a job name of anything other than "new" was specified.
# If a Project id is specified, and the Project has a stored prefix, job creation should fail if that the job is not created with the name "[prefix]-new".
# If a Project id is specified, and the Project has a stored prefix, and the prefix matches the expected value and the new job name is "[prefix]-new", then job creation should succeed.
#
#
#
# Limitations:
# * This assumes old jobs aren't deleted; it will re-use job numbers
#   if jobs are deleted.
# * This dynamically checks existing jobs to determine the next
#   available job number.  The current implementation is not
#   scalable to large numbers of jobs.  (TO DO:  Use a 'p4
#   key' to recall the highest number for a given project and
#   the key value).
# * Mutex locking is needed.  This implementations allows for the
#   theoretical possibility of a race condition where to users
#   creating new jobs at the same time could collide.  (TO DO:
#   Use a 'p4 key' to implement a semaphore to prevent the
#   unlikely chance of a race condition).
#
# This script has the following runtime dependencies:
# This assumes the Perforce context and environment is appropriate, i.e.:
#  * The preferred 'p4' executable is in the path.
#
#  * P4PORT is set appropriately.
#
#  * P4USER is defined as a currently logged in user (as is typical
#    for Perforce trigger scripts which operate on the Perforce server
#    machine).
#
#  * The BASH_VERSION must be 4.0 or higher, new enough to support the
#    =~ (regular expression matching) syntax.  This is ubiquitous for
#    modern Linux distros.  On Mac OSX, at least up thru 10.10.3/Yosemite,
#    a newer bash must be acquired.  As one of several examples of
#    how to do this, see: http://clubmate.fi/upgrade-to-bash-4-in-mac-os-x/

# Declarations
set -u
set -e

THISSCRIPT=${0##*/}

# Usage: bail "message" [optional_exit_code]
function bail () {
   echo -e "\n$THISSCRIPT v$VERSION: Error: ${1:-Unknown Error}\n"
   exit ${2:-1}
}

[[ $# -eq 1 ]] || bail "Bad usage: Missing %formfile% argument."

declare oldFormFile=$1
declare newFormFile="${oldFormFile}.NEW.$$.$RANDOM.tmp"
declare -i nextJobNum=1
declare thisJobNum=0
declare -i highestJobNum=0
declare -i changed=0
declare job=

[[ -r $oldFormFile ]] || bail "Error: Missing form file [$oldFormFile]."

while read line; do
   [[ $line == "#"* ]] && continue
   [[ $line != "Job:"* ]] && continue
   job=${line#Job:}
   job=$(echo $job)
   [[ $job == new ]] && continue
   [[ $job =~ job[0-9]{6}$ ]] && continue
   [[ $job =~ ^.+-[1-9][0-9]*$ ]] && continue

   if [[ $job =~ ^.+-new$ ]]; then
      changed=1
      projName=${line#Job:}
      projName=${projName%-new}
      projName=$(echo $projName)

      jobSearchCmd="p4 -ztag -F %Job% jobs -e 'Job=${projName}*'"

      for job in $(eval $jobSearchCmd); do
         thisJobNum=${job##*-}
         # Confirm '$thisJobNum' really is purly numeric, so we can do math on it.
         if [[ $thisJobNum =~ ^[1-9]+$ ]]; then
            [[ $thisJobNum -gt $highestJobNum ]] && highestJobNum=$thisJobNum
         fi
      done
      nextJobNum=$(($highestJobNum+1))
   else
      bail "Malformd job name [$job].  Sample valid values are:\n\tnew\n\tjob123456\n\tPRJ-33\n\tPRJ-new\n\tPRJ-2-new\n\n"
   fi
done < $oldFormFile

if [[ $changed -eq 1 ]]; then
   sed "s:${projName}-new:${projName}-${nextJobNum}:g" $oldFormFile > $newFormFile ||\
      bail "Failed to update job number."
   /bin/mv -f "$newFormFile" "$oldFormFile" || bail "Failed to update job number."
fi

/bin/rm -f "$newFormFile"

exit 0