+#!/bin/bash
+# Desc: Initializes a git repository
+
+yell() { echo "$0: $*" >&2; } #o Yell, Die, Try Three-Fingered Claw technique
+die() { yell "$*"; exit 111; } #o Ref/Attrib: https://stackoverflow.com/a/25515370
+try() { "$@" || die "cannot $*"; } #o
+checkURL() {
+ # Desc: Checks if string is a valid URL.
+ # Warning: Does not correctly handle multi-byte characters.
+ # Version: 0.0.2
+ # Input: arg1: string
+ # Output: return code 0: string is a valid URL
+ # return code 1: string is NOT a valid URL
+ # Depends: Bash 5.0.3
+ # Ref/Attrib: https://stackoverflow.com/a/3184819
+ regex='(https?|ftp|file|ssh|git)://[-A-Za-z0-9\+&@#/%?=~_|!:,.;]*[-A-Za-z0-9\+&@#/%=~_|]'
+ arg1="$1";
+ if [[ $arg1 =~ $regex ]]; then
+ return 0;
+ else
+ return 1;
+ fi;
+} # Check if arg1 is valid URL
+initGitRepo() {
+ # Desc: Creates, adds remotes to, and pulls to git repository
+ # Note: Does nothing if repoDir is already initialized git repo.
+ # Usage: createGitRepo arg1 arg2 arg3 arg4
+ # Input: arg1: repoURL
+ # arg2: repoDir
+ # arg3: remoteName
+ # arg4: branchName
+ # Version: 0.0.4
+ # Depends: checkURL() 0.0.2, yell(), Bash 5.0.3
+ # Ref/Attrib: [1]: Test for space-less alphanuemric string. https://unix.stackexchange.com/a/416120
+ # [2]: Test for argument count. https://stackoverflow.com/q/18568706
+ # [3]: Test if dir is (in) git repository. https://stackoverflow.com/a/39518382
+ #==BEGIN Validate input arguments==
+ arg1="$1";
+ arg2="$2";
+ arg3="$3";
+ arg4="$4";
+ # Validate repoURL
+ if checkURL "$arg1"; then repoURL="$arg1";
+ else yell "ERROR:Not a valid URL:$arg1"; return 1; fi;
+
+ # Validate remoteName
+ if [[ "$arg3" =~ ^[[:alnum:]]+$ ]]; then remoteName="$arg3";
+ else yell "ERROR:Not a valid remote name:$arg3"; return 1; fi; # See [1].
+
+ # Validate branchName
+ if [[ "$arg4" =~ ^[[:alnum:]]+$ ]]; then branchName="$arg4";
+ else yell "ERROR:Not a valid remote branch name:$arg4"; return 1; fi; # See [1].
+
+ # Check argument count
+ if [[ $# -gt 4 ]]; then yell "ERROR:Too many arguments."; return 1; fi; # See [2].
+ #==END Validate input arguments==
+ #==BEGIN create and populate git repository==
+ if [[ ! -d "$repoDir" ]]; then mkdir "$repoDir"; fi;
+ pushd "$repoDir" || return 1;
+ if ! git -C "$(pwd)" rev-parse 1>/dev/null 2>&1; then
+ yell "STATUS:Initializing as git repo:$repoDir";
+ git init; # Init repo if not already a git repo. See [3]
+ else
+ yell "STATUS:Already a git repository:$repoDir";
+ git status; git remote -v;
+ yell "STATUS:Pausing 4 seconds..."; sleep 4;
+ fi;
+ yell "STATUS:Adding $repoURL as remote $remoteName";
+ git remote add "$remoteName" "$repoURL";
+ yell "STATUS:Pulling branch $branchName from remote $remoteName";
+ git pull "$remoteName" "$branchName";
+ unset repoURL repoDir remoteName branchName;
+ popd || exit 1;
+ #==END create and populate git repository==
+} # Init Git Repository
+
+#==BEGIN test code
+tmpDir=/tmp/"$(date +%Y%m%dT%H%M%S%z)";
+mkdir -p "$tmpDir";
+pushd "$tmpDir" || exit 1;
+
+repoURL="https://zdv2.bktei.com/gitweb/baltakatei-exdev.git";
+repoDir="BK-2020-03..bkexdev";
+remoteName="zdv2";
+branchName="master";
+initGitRepo "$repoURL" "$repoDir" "$remoteName" "$branchName";
+unset repoURL repoDir remoteName branchName;
+
+yell "STATUS:Done.";
+#==END test code