[maven] add script to generate maven submodules project

This commit adds a shell script which:

* move current elasticsearch core source in `/core`
* fetch `elasticsearch-parent` project in `/`
* fetch plugins in `/plugins`
* change `groupId` for all plugins to `org.elasticsearch.plugin` so versions won't conflict in maven central
* remove plugins/name/dev-tools dir which is not needed anymore
* remove plugins/name/.git dir
* remove plugins/name/LICENSE and plugins/name/CONTRIBUTING files
* clean `core/pom.xml` of useless settings that are inherited from parent project.
* `core/pom.xml` is adapted to change location of rest tests definition (`../`)
* change core name to `Elasticsearch Core`
* remove `plugins` dir from `.gitignore`

Plugins added:

* Analysis
  * analysis-kuromoji
  * analysis-smartcn
  * analysis-stempel
  * analysis-phonetic
  * analysis-icu

* Mapper
  * mapper-attachments

* Language
  * lang-python
  * lang-mvel
  * lang-javascript

* Cloud
  * cloud-gce
  * cloud-azure
  * cloud-aws

River plugins are ignored but might be added if we want to.

Todo:

* check and adapt our release tool. It now has to upload all submodules as well.
* adapt Jenkins jobs

.gitignore

@@ -5,7 +5,7 @@
 *.iws
 work/
 /data/
-/plugins/
+#/plugins/
 logs/
 .DS_Store
 build/

migrate.sh

@@ -0,0 +1,211 @@
+#!/bin/bash
+
+# This script creates a new branch then migrate all the maven stuff in it and commit that branch.
+# then it runs mvn install to check that everything is still running
+
+# Useful commands while testing
+# rm -rf migration/tmp plugins
+# git checkout pr/migration_script -f
+# git add .; git commit -m "Add migration script" --amend
+# ./migrate.sh 
+# mvn clean install -DskipTests
+
+DIR_TMP="migration"
+MODULE_CORE="core"
+GIT_BRANCH="refactoring/maven"
+PARENT_NAME="elasticsearch-parent"
+PARENT_GIT="https://github.com/elastic/elasticsearch-parent.git"
+
+# Insert a new text after a given line
+# insertLinesAfter text_to_find text_to_add newLine_separator filename
+# insertLinesAfter "<\/project>" "   <modules>=   <\/modules>" "§" "pom.xml"
+function insertLinesAfter() {
+	# echo "## modify $4 with $2"
+	sed "s/$1/$1$3$2/" $4 | tr "$3" "\n" > $4.new
+	mv $4.new $4
+}
+
+# Insert a new text before a given line
+# insertLinesBefore text_to_find text_to_add newLine_separator filename
+# insertLinesBefore "<\/project>" "   <modules>=   <\/modules>" "§" "pom.xml"
+function insertLinesBefore() {
+	# echo "## modify $4 with $2"
+	sed "s/$1/$2$3$1/" $4 | tr "$3" "\n" > $4.new
+	mv $4.new $4
+}
+
+# Replace text in a file
+# replaceLine old_text new_text filename
+# replaceLine "old" "new" "pom.xml"
+function replaceLine() {
+	# echo "## modify $3 with $2"
+	sed "s/^$1/$2/" $3 > $3.new
+	mv $3.new $3
+}
+
+# Remove lines in a file
+# removeLines from_text_included to_text_included filename
+# removeLines "old" "new" "pom.xml"
+function removeLines() {
+	# echo "## remove lines in $3 from $1 to $2"
+	sed "/$1/,/$2/d" $3 > $3.new
+	mv $3.new $3
+}
+
+# Migrate a plugin
+# migratePlugin short_name
+function migratePlugin() {
+	PLUGIN_GIT_REPO="https://github.com/elastic/elasticsearch-$1.git"
+
+	echo "## Add $1 module from $PLUGIN_GIT_REPO"
+
+	# echo "### fetch $1 project from $PLUGIN_GIT_REPO in plugins"
+	# If you want to run that locally, uncomment this line and comment one below
+	#cp -r ../elasticsearch-$1/* plugins/$1
+	git clone $PLUGIN_GIT_REPO plugins/$1 > /dev/null 2>/dev/null
+
+	# We can now add plugin module
+	insertLinesBefore "    <\/modules>" "        <module>$1<\/module>" "§" "plugins/pom.xml"
+
+	# echo "### change $1 groupId to org.elasticsearch.plugins"
+	# Change the groupId to avoid conflicts with existing 2.0.0 versions.
+	replaceLine "    <groupId>org.elasticsearch<\/groupId>" "    <groupId>org.elasticsearch.plugin<\/groupId>" "plugins/$1/pom.xml"
+
+	# echo "### cleanup $1 pom.xml"
+	removeLines "<issueManagement>" "<\/issueManagement>" "plugins/$1/pom.xml"
+	removeLines "<repositories>" "<\/repositories>" "plugins/$1/pom.xml"
+	removeLines "<url>" "<\/scm>" "plugins/$1/pom.xml"
+
+	# echo "### remove version 3.0.0-SNAPSHOT from $1 pom.xml"
+	# All plugins for ES 2.0.0 uses 3.0.0-SNAPSHOT version number
+	replaceLine "    <version>3.0.0-SNAPSHOT<\/version>" "" "plugins/$1/pom.xml"
+
+	# echo "### remove unused dev-tools and .git dirs and LICENSE.txt and CONTRIBUTING.md files"
+	rm -r plugins/$1/dev-tools
+	rm -rf plugins/$1/.git
+	rm plugins/$1/LICENSE.txt
+	rm plugins/$1/CONTRIBUTING.md
+
+	# echo "### commit changes"
+	git add .
+	git commit -m "add $1 module" > /dev/null
+}
+
+echo "# STEP 0 : prepare the job"
+
+# echo "## clean $DIR_TMP plugins dev-tools/target target"
+rm -rf $DIR_TMP 
+rm -rf plugins 
+rm -rf dev-tools/target
+rm -rf target
+
+# echo "## create git $GIT_BRANCH work branch"
+
+# It first clean the existing branch if any
+git branch -D $GIT_BRANCH > /dev/null
+
+# Create the new branch
+git branch $GIT_BRANCH > /dev/null
+git checkout $GIT_BRANCH > /dev/null 2>/dev/null
+
+echo "# STEP 1 : Core module"
+
+# create the tmp work dir
+# echo "## create $DIR_TMP temporary dir"
+mkdir $DIR_TMP
+
+# create the core module
+# echo "## create core module in $MODULE_CORE"
+rm -rf $MODULE_CORE 
+mkdir $MODULE_CORE
+# echo "## create $MODULE_CORE pom.xml"
+cp pom.xml $MODULE_CORE
+# echo "## modify $MODULE_CORE/pom.xml"
+# We move <parent></parent> block on top
+removeLines "<parent>" "<\/parent>" "$MODULE_CORE/pom.xml"
+insertLinesAfter "<\/modelVersion>" "    <parent>§        <groupId>org.elasticsearch<\/groupId>§        <artifactId>elasticsearch-parent<\/artifactId>§        <version>2.0.0-SNAPSHOT<\/version>§    <\/parent>§" "§" "$MODULE_CORE/pom.xml"
+# We clean useless data
+replaceLine "    <version>2.0.0-SNAPSHOT<\/version>" "" "$MODULE_CORE/pom.xml"
+removeLines "<inceptionYear>" "<\/scm>" "$MODULE_CORE/pom.xml"
+removeLines "<repositories>" "<\/repositories>" "$MODULE_CORE/pom.xml"
+
+# echo "## move src in $MODULE_CORE"
+git mv src/ $MODULE_CORE
+# echo "## move bin in $MODULE_CORE"
+git mv bin/ $MODULE_CORE
+# echo "## move config in $MODULE_CORE"
+git mv config/ $MODULE_CORE 
+# echo "## move lib in $MODULE_CORE"
+git mv lib/ $MODULE_CORE 
+# echo "## copy README.textile, LICENSE.txt and NOTICE.txt in $MODULE_CORE"
+cp README.textile $MODULE_CORE 
+cp LICENSE.txt $MODULE_CORE 
+cp NOTICE.txt $MODULE_CORE 
+# echo "## modify rest-api-spec location in $MODULE_CORE/pom.xml"
+replaceLine "                <directory>\${project.basedir}\/rest-api-spec<\/directory>" "                <directory>\${project.basedir}\/..\/rest-api-spec<\/directory>" "$MODULE_CORE/pom.xml"
+
+
+# echo "## commit changes"
+git add .
+git commit -m "create $MODULE_CORE module" > /dev/null
+
+echo "# STEP 2 : Parent pom.xml from $PARENT_GIT"
+
+# echo "## fetch parent project from $PARENT_GIT in $DIR_TMP"
+# If you want to run that locally, uncomment this line and comment one below
+# cp -r ../elasticsearch-parent $DIR_TMP
+git clone $PARENT_GIT $DIR_TMP/$PARENT_NAME > /dev/null 2>/dev/null
+
+cp $DIR_TMP/$PARENT_NAME/pom.xml .
+cp -r $DIR_TMP/$PARENT_NAME/dev-tools .
+cp -r $DIR_TMP/$PARENT_NAME/plugins .
+
+# echo "## commit changes"
+git add .
+git commit -m "create parent pom project from its original location" > /dev/null
+
+echo "# STEP 3 : Add $MODULE_CORE module to pom.xml"
+
+insertLinesBefore "    <\/modules>" "        <module>$MODULE_CORE<\/module>" "§" "pom.xml"
+
+# echo "## change name to Elasticsearch Core"
+replaceLine "    <name>Elasticsearch core<\/name>" "    <name>Elasticsearch Core<\/name>" "$MODULE_CORE/pom.xml"
+
+# echo "## commit changes"
+git add .
+git commit -m "add core module" > /dev/null
+
+echo "# STEP 4 : Migrate plugins"
+
+# We need to add <modules></modules> in the plugins parent project as it does not exist
+insertLinesBefore "<\/project>" "    <modules>§    <\/modules>" "§" "plugins/pom.xml"
+
+# Analysis
+migratePlugin "analysis-kuromoji" 
+migratePlugin "analysis-smartcn"
+migratePlugin "analysis-stempel"
+migratePlugin "analysis-phonetic"
+migratePlugin "analysis-icu"
+
+# Mapper
+migratePlugin "mapper-attachments"
+
+# Language
+migratePlugin "lang-python"
+migratePlugin "lang-mvel"
+migratePlugin "lang-javascript"
+
+# Cloud
+migratePlugin "cloud-gce"
+migratePlugin "cloud-azure"
+migratePlugin "cloud-aws"
+
+echo "# STEP 5 : Clean tmp dir"
+
+# echo "## clean $DIR_TMP"
+rm -rf $DIR_TMP 
+
+echo "you can now run:"
+echo "mvn clean install -DskipTests"
+
+