GIT_BRANCH environment variable handling + add some docs

scripts/export_src.sh

@@ -1,31 +1,49 @@
 #!/bin/sh
 
+# Description:
+#   Creates archive with source code of multiple repositories.
+#
+# Parameters:
+#   $1 - github repository name without suffix (project name).
+#   $2, $3, ..., $n - repository suffixes (platforms).
+#
+# Optional environment variables:
+#   GIT_BRANCH - branch to use. Default - master.
+#
+# Example of usage:
+#   export_src.sh TestProject ios android backend
+#   GIT_BRANCH="develop"; ./export_src.sh TestProject ios web
+#
+
+if [ -z "${GIT_BRANCH}" ]; then
+    GIT_BRANCH="master"
+fi
+
 PROJECT_NAME=$1
-SRC_FOLDER_NAME=${PROJECT_NAME}-src-$(date +%F)
+SRC_FOLDER_NAME="${PROJECT_NAME}-src-$(date +%F)"
-SRC_DIR=./${SRC_FOLDER_NAME}
+SRC_DIR="./${SRC_FOLDER_NAME}"
 
 COMMAND_LINE_ARGUMENTS=$@
 
 clone_platform() {
-    PROJECT_DIR=$1
+    PROJECT_NAME=$1
     PLATFORM=$2
 
-    git clone --recurse-submodules -j8 git@github.com:TouchInstinct/${PROJECT_DIR}-${PLATFORM}.git --branch master
+    git clone --recurse-submodules -j8 "git@github.com:TouchInstinct/${PROJECT_NAME}-${PLATFORM}.git" --branch "${GIT_BRANCH}"
 }
 
-mkdir -p ${SRC_DIR}
+mkdir -p "${SRC_DIR}"
-cd ${SRC_DIR}
+cd "${SRC_DIR}"
 
 for argument in ${COMMAND_LINE_ARGUMENTS}
 do
-  if [ $argument != $PROJECT_NAME ]
+  if [ $argument != $PROJECT_NAME ]; then
-  then
     platform=${argument} # all arguments after project name treated as platforms
     clone_platform ${PROJECT_NAME} ${platform}
   fi
 done
 
 find . -name ".git*" -print0 | xargs -0 rm -rf
-zip -r ${SRC_FOLDER_NAME}.zip .
+zip -r -q ${SRC_FOLDER_NAME}.zip .
 
 open .