| ========================================== |
| zktreeutil - Zookeeper Tree Data Utility |
| Author: Anirban Roy |
| Organization: Yahoo Inc. |
| ========================================== |
| |
| zktreeutil program is intended to manage and manipulate zk-tree data quickly, effi- |
| ciently and with ease. The utility operates on free-form ZK-tree and hence can be used |
| for any cluster managed by Zookeeper. Here are the basic functionalities - |
| |
| EXPORT: The whole/partial ZK-tree is exported into a XML file. This helps in |
| capturing a current snapshot of the data for backup/analysis. For a subtree |
| export, one need to specify the path to the ZK-subtree with proper option. |
| |
| IMPORT: The ZK-tree can be imported from XML into ZK cluster. This helps in priming |
| the new ZK cluster with static configuration. The import can be non-intrusive by |
| making only the additions in the existing data. The import of subtree is also |
| possible by optionally providing the path to the ZK-subtree. |
| |
| DIFF: Creates a diff between live ZK data vs data saved in XML file. Diff can ignore |
| some ZK-tree branches (possibly dynamic data) on reading the optional ignore flag |
| from XML file. Diffing on a ZK-subtree achieved by providing path to ZK-subtree with |
| diff command. |
| |
| UPDATE: Make the incremental changes into the live ZK-tree from saved XML, essentia- |
| lly after running the diff. |
| |
| DUMP: Dumps the ZK-tree on the standard output device reading either from live ZK |
| server or XML file. Like export, ZK-subtree can be dumped with optionaly |
| providing the path to the ZK-subtree, and till a certain depth of the (sub)tree. |
| |
| The exported ZK data into XML file can be shortened by only keeping the static ZK |
| nodes which are required to prime a cluster. The dynamic zk nodes (created on-the- |
| fly) can be ignored by setting a 'ignore' attribute at the root node of the dynamic |
| subtree (see tests/zk_sample.xml), possibly deleting all inner ZK nodes under that. |
| Once ignored, the whole subtree is ignored during DIFF, UPDATE and WRITE. |
| |
| Pre-requisites |
| -------------- |
| 1. Linux system with 2.6.X kernel. |
| 2. Zookeeper C client library (locally built at ../../c/.libs) >= 3.X.X |
| 3. Development build libraries (rpm packages): |
| a. boost-devel >= 1.32.0 |
| b. libxml2-devel >= 2.7.3 |
| c. log4cxx0100-devel >= 0.10.0 |
| |
| Build instructions |
| ------------------ |
| 1. cd into this directory |
| 2. autoreconf -if |
| 3. ./configure |
| 4. make |
| 5. 'zktreeutil' binary created under src directory |
| |
| Limitations |
| ----------- |
| Current version works with text data only, binary data will be supported in future |
| versions. |
| |
| Testing and usage of zktreeutil |
| -------------------------------- |
| 1. Run Zookeeper server locally on port 2181 |
| 2. export LD_LIBRARY_PATH=../../c/.libs/:/usr/local/lib/ |
| 3. ./src/zktreeutil --help # show help |
| 4. ./src/zktreeutil --zookeeper=localhost:2181 --import --xmlfile=tests/zk_sample.xml 2>/dev/null # import sample ZK tree |
| 5. ./src/zktreeutil --zookeeper=localhost:2181 --dump --path=/myapp/version-1.0 2>/dev/null # dump Zk subtree |
| 5. ./src/zktreeutil --zookeeper=localhost:2181 --dump --depth=3 2>/dev/null # dump Zk tree till certain depth |
| 6. ./src/zktreeutil --xmlfile=zk_sample.xml -D 2>/dev/null # dump the xml data |
| 7. Change zk_sample.xml with adding/deleting/chaging some nodes |
| 8. ./src/zktreeutil -z localhost:2181 -F -x zk_sample.xml -p /myapp/version-1.0/configuration 2>/dev/null # take a diff of changes |
| 9. ./src/zktreeutil -z localhost:2181 -E 2>/dev/null > zk_sample2.xml # export the mofied ZK tree |
| 10. ./src/zktreeutil -z localhost:2181 -U -x zk_sample.xml -p /myapp/version-1.0/distributions 2>/dev/null # update with incr. changes |
| 11. ./src/zktreeutil --zookeeper=localhost:2181 --import --force --xmlfile=zk_sample2.xml 2>/dev/null # re-prime the ZK tree |
| |
