Douglas and Harsh - Thanks a lot for the immediate and detailed replies! Looks like both of these would work well for me.
In order to start trying these, I have tried a few things to get started with Avro, but this is where I am stuck: 1. I first downloaded the stable version in the form of "avro-1.6.1.tar.gz". (I am working out all this on a Ubuntu 10.04 machine). I don't find a readme file and am not familar with installing a python package, so I am not sure if what I am doing is correct. After some basic googling, I did: avro-1.6.1$ ./setup.py build This appears to complete successfully. Then when I do this: ...avro-1.6.1$ sudo ./setup.py install I get an error message. (pasted at the end of this mail [1]) 2. I tried the technique suggested by Harsh, but it ends with a similar error as pasted below in [2] /avro$ sudo easy_install avro Then I tried to install snappy by itself: /avro$ sudo easy_install python-snappy I get the same error. Also I read that that this might help with this type of error, so I tried: avro$ sudo apt-get install python2.6-dev I ensured I have gcc and installed g++ too (because I wasn't sure what was needed). I did see a similar error message reported here for Avro and OS X: https://issues.apache.org/jira/browse/AVRO-981 Before installing g++ and python-dev, the error message I was seeing from easy_install python_snappy was different and shorter (attached below) [3]. Sorry if I should just be reading up on general Python development or packages or installs (and/or other things), before I should even be attempting to do this. I'll be doing that now to move further. But in case anyone might have suggestions for the errors I am seeing, that would be great. I did find this Quick Start Guide from the main Avro wiki page, but when I look through the Python example it is once again focussed client/server and RPC communication between them: https://github.com/phunt/avro-rpc-quickstart Also my understanding is that I must 'install' or deploy Avro before I can try out the C bindings suggested by Douglas. I am stating this since I am not exactly clear by what this meant: - "especially since the C bindings don't have any library dependencies to install". I am assuming it means, I don't need anything *beyond* a basic install of Avro. 3. With regards to the two suggested ways, would either of these techniques allow me to filter my data records using some sort of a condition on a field?(or a few fields) If not it seems like I would have to resort to first grepping the log file with the condition I want, and then using either of these two techniques to convert to CSV file. This would still be much better than what I am doing now, which is through not-so-pretty awk invocations to retrieve the fields I need (after the initial grep). But if the existing API, allows me to scan through the log file and specify conditions for fields, it might be much more efficient. I can imagine that I might have to use the low-level API and write a program to do this, but I am not sure at this point how to get started on this. Any pointers would be really helpful! Thank you, Selvi [1] /avro-1.6.1$ sudo ./setup.py install running install Checking .pth file support in /usr/local/lib/python2.6/dist-packages/ /usr/bin/python -E -c pass TEST PASSED: /usr/local/lib/python2.6/dist-packages/ appears to support .pth files running bdist_egg running egg_info writing requirements to avro.egg-info/requires.txt writing avro.egg-info/PKG-INFO writing top-level names to avro.egg-info/top_level.txt writing dependency_links to avro.egg-info/dependency_links.txt reading manifest file 'avro.egg-info/SOURCES.txt' writing manifest file 'avro.egg-info/SOURCES.txt' installing library code to build/bdist.linux-x86_64/egg running install_lib running build_py creating build/bdist.linux-x86_64 creating build/bdist.linux-x86_64/egg creating build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/io.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/datafile.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/tool.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/txipc.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/ipc.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/protocol.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/__init__.py -> build/bdist.linux-x86_64/egg/avro copying build/lib.linux-x86_64-2.6/avro/schema.py -> build/bdist.linux-x86_64/egg/avro byte-compiling build/bdist.linux-x86_64/egg/avro/io.py to io.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/datafile.py to datafile.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/tool.py to tool.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/txipc.py to txipc.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/ipc.py to ipc.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/protocol.py to protocol.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/__init__.py to __init__.pyc byte-compiling build/bdist.linux-x86_64/egg/avro/schema.py to schema.pyc creating build/bdist.linux-x86_64/egg/EGG-INFO installing scripts to build/bdist.linux-x86_64/egg/EGG-INFO/scripts running install_scripts running build_scripts creating build/bdist.linux-x86_64/egg/EGG-INFO/scripts copying build/scripts-2.6/avro -> build/bdist.linux-x86_64/egg/EGG-INFO/scripts changing mode of build/bdist.linux-x86_64/egg/EGG-INFO/scripts/avro to 755 copying avro.egg-info/PKG-INFO -> build/bdist.linux-x86_64/egg/EGG-INFO copying avro.egg-info/SOURCES.txt -> build/bdist.linux-x86_64/egg/EGG-INFO copying avro.egg-info/dependency_links.txt -> build/bdist.linux-x86_64/egg/EGG-INFO copying avro.egg-info/requires.txt -> build/bdist.linux-x86_64/egg/EGG-INFO copying avro.egg-info/top_level.txt -> build/bdist.linux-x86_64/egg/EGG-INFO zip_safe flag not set; analyzing archive contents... creating dist creating 'dist/avro-1.6.1-py2.6.egg' and adding 'build/bdist.linux-x86_64/egg' to it removing 'build/bdist.linux-x86_64/egg' (and everything under it) Processing avro-1.6.1-py2.6.egg Removing /usr/local/lib/python2.6/dist-packages/avro-1.6.1-py2.6.egg Copying avro-1.6.1-py2.6.egg to /usr/local/lib/python2.6/dist-packages avro 1.6.1 is already the active version in easy-install.pth Installing avro script to /usr/local/bin Installed /usr/local/lib/python2.6/dist-packages/avro-1.6.1-py2.6.egg Processing dependencies for avro==1.6.1 Searching for python-snappy Reading http://pypi.python.org/simple/python-snappy/ Reading http://github.com/andrix/python-snappy Best match: python-snappy 0.3.2 Downloading http://pypi.python.org/packages/source/p/python-snappy/python-snappy-0.3.2.tar.gz#md5=94ec3eb54a780fac3b15a6c141af973f Processing python-snappy-0.3.2.tar.gz Running python-snappy-0.3.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-1J0R1s/python-snappy-0.3.2/egg-dist-tmp-luBG6u cc1plus: warning: command line option "-Wstrict-prototypes" is valid for Ada/C/ObjC but not for C++ snappymodule.cc:31:22: error: snappy-c.h: No such file or directory snappymodule.cc: In function ‘PyObject* snappy__compress(PyObject*, PyObject*)’: snappymodule.cc:62: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:62: error: expected ‘;’ before ‘status’ snappymodule.cc:75: error: ‘snappy_max_compressed_length’ was not declared in this scope snappymodule.cc:79: error: ‘status’ was not declared in this scope snappymodule.cc:79: error: ‘snappy_compress’ was not declared in this scope snappymodule.cc:81: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: In function ‘PyObject* snappy__uncompress(PyObject*, PyObject*)’: snappymodule.cc:107: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:107: error: expected ‘;’ before ‘status’ snappymodule.cc:120: error: ‘status’ was not declared in this scope snappymodule.cc:120: error: ‘snappy_uncompressed_length’ was not declared in this scope snappymodule.cc:121: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc:128: error: ‘snappy_uncompress’ was not declared in this scope snappymodule.cc:129: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: In function ‘PyObject* snappy__is_valid_compressed_buffer(PyObject*, PyObject*)’: snappymodule.cc:151: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:151: error: expected ‘;’ before ‘status’ snappymodule.cc:156: error: ‘status’ was not declared in this scope snappymodule.cc:156: error: ‘snappy_validate_compressed_buffer’ was not declared in this scope snappymodule.cc:157: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: At global scope: snappymodule.cc:41: warning: ‘_state’ defined but not used error: Setup script exited with error: command 'gcc' failed with exit status 1 ...avro/avro-1.6.1$ avro --help ************************************************************************ [2] /avro$ sudo easy_install avro Searching for avro Best match: avro 1.6.1 Processing avro-1.6.1-py2.6.egg avro 1.6.1 is already the active version in easy-install.pth Installing avro script to /usr/local/bin Using /usr/local/lib/python2.6/dist-packages/avro-1.6.1-py2.6.egg Processing dependencies for avro Searching for python-snappy Reading http://pypi.python.org/simple/python-snappy/ Reading http://github.com/andrix/python-snappy Best match: python-snappy 0.3.2 Downloading http://pypi.python.org/packages/source/p/python-snappy/python-snappy-0.3.2.tar.gz#md5=94ec3eb54a780fac3b15a6c141af973f Processing python-snappy-0.3.2.tar.gz Running python-snappy-0.3.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-c6jLm0/python-snappy-0.3.2/egg-dist-tmp-TTWQBN cc1plus: warning: command line option "-Wstrict-prototypes" is valid for Ada/C/ObjC but not for C++ snappymodule.cc:31:22: error: snappy-c.h: No such file or directory snappymodule.cc: In function ‘PyObject* snappy__compress(PyObject*, PyObject*)’: snappymodule.cc:62: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:62: error: expected ‘;’ before ‘status’ snappymodule.cc:75: error: ‘snappy_max_compressed_length’ was not declared in this scope snappymodule.cc:79: error: ‘status’ was not declared in this scope snappymodule.cc:79: error: ‘snappy_compress’ was not declared in this scope snappymodule.cc:81: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: In function ‘PyObject* snappy__uncompress(PyObject*, PyObject*)’: snappymodule.cc:107: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:107: error: expected ‘;’ before ‘status’ snappymodule.cc:120: error: ‘status’ was not declared in this scope snappymodule.cc:120: error: ‘snappy_uncompressed_length’ was not declared in this scope snappymodule.cc:121: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc:128: error: ‘snappy_uncompress’ was not declared in this scope snappymodule.cc:129: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: In function ‘PyObject* snappy__is_valid_compressed_buffer(PyObject*, PyObject*)’: snappymodule.cc:151: error: ‘snappy_status’ was not declared in this scope snappymodule.cc:151: error: expected ‘;’ before ‘status’ snappymodule.cc:156: error: ‘status’ was not declared in this scope snappymodule.cc:156: error: ‘snappy_validate_compressed_buffer’ was not declared in this scope snappymodule.cc:157: error: ‘SNAPPY_OK’ was not declared in this scope snappymodule.cc: At global scope: snappymodule.cc:41: warning: ‘_state’ defined but not used error: Setup script exited with error: command 'gcc' failed with exit status 1 ************************************************************************ [3] python$ sudo easy_install python-snappy Searching for python-snappy Reading http://pypi.python.org/simple/python-snappy/ Reading http://github.com/andrix/python-snappy Best match: python-snappy 0.3.2 Downloading http://pypi.python.org/packages/source/p/python-snappy/python-snappy-0.3.2.tar.gz#md5=94ec3eb54a780fac3b15a6c141af973f Processing python-snappy-0.3.2.tar.gz Running python-snappy-0.3.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-Hpzssm/python-snappy-0.3.2/egg-dist-tmp-UStJPW gcc: error trying to exec 'cc1plus': execvp: No such file or directory error: Setup script exited with error: command 'gcc' failed with exit status 1 On Tue, Jan 24, 2012 at 11:01 AM, Harsh J <[email protected]> wrote: > Selvi, > > Expanding on Douglas' response, if you have installed Avro's python > libraries (Simplest way to get latest stable is: "easy_install avro", > or install from the distribution -- Post back if you need help on > this), you can simply do, using the now-installed 'avro' executable: > > $ ls > sample_input.avro > > $ avro cat sample_input.avro --format csv > 011990-99999,0,-619524000000 > 011990-99999,22,-619506000000 > 011990-99999,-11,-619484400000 > 012650-99999,111,-655531200000 > 012650-99999,78,-655509600000 > > Or, write to a resultant file, as you would regularly in a shell: > > $ avro cat sample_input.avro --format csv > sample_input.csv > > For more options on avro's cat and write opts: > > $ avro --help > > On Tue, Jan 24, 2012 at 9:01 PM, selvi k <[email protected]> wrote: > > Hello All, > > > > > > I would like some suggestions on where I can start in the Avro project. > > > > > > I want to be able to read from an Avro formatted log file (specifically > the > > History Log file created at the end of a Hadoop job) and create a Comma > > Separated file of certain log entries. I need a csv file because this is > the > > format that is accepted by post processing software I am working with > (eg: > > Matlab). > > > > > > Initially I was using a BASH script to grep and awk from this file and > > create my CSV file because I needed a very few values from it, and a > quick > > script just worked. I didn't try to get to know what format the log file > was > > in and utilize that. (my bad!) Now that I need to be scaling up and > want to > > have a reliable way to parse, I would like to try and do it the right > way. > > > > > > My question is this: For the above goal, could you please guide me with > > steps I can follow - such as reading material and libraries I could try > to > > use. As I go through the Quick Start Guide and FAQ, I see that a lot of > the > > information here is geared to someone who wants to use the data > > serialization and RPC functionality provided by Avro. Given that I only > want > > to be able to "read", where may I start? > > > > > > I can comfortably script with BASH and Perl. Given that I only see > support > > for Java, Python and Ruby, I think I can take this as as opportunity to > > learn Python and get up to speed. > > > > > > Thanks a lot. > > > > > > -Selvi > > > > > > > > -- > Harsh J > Customer Ops. Engineer, Cloudera >
