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Need code for importing .csv file via python or ruby code to Cassandra 3.11.3 DB (Production use)

We have 7 node Cassandra 3.11.3 production cluster, we get ticket details dump to a mid server, I need to read from this .csv file and import .csv data to cassandra table. I tried ruby code which was easy for me to write but it does not take care of all the column values (As this .csv will have special characters, enters/different lines, UTF issues, too much of text description as it is in ticketing tool) as data keep changing in each and every row in .csv.
I Want to know if ruby or python is good to perform this activity in production or does anyone have good sample code for mitigating issues mentioned above and performing this kind of activity in production environment?

Both Ruby and Python are perfect for this kind of task, but if your source file is in bad format then any potential tool could fail - there is no magic button tool that could deduce the context from the (broken) data file and fix all the problems for you automatically.
I'd suggest splitting the task into two parts: 1) fix the encoding and data quality problem(s) (and perform any data transformations if necessary) and then 2) import clean data.
Task 2 could be easily done with almost any programming language (that has appropriate cassandra driver available) but if you have a well-formatted csv source you probably don't need any hacking at all (depending on the use case, of course) - Cassandra supports copy ... from command that allows importing data from csv directly (https://docs.datastax.com/en/cql/3.3/cql/cql_reference/cqlshCopy.html).

create pdf from python

I'm looking to generate PDF's from a Python application.
They start relatively simple but some may become more complex (Essentially letter like documents but will include watermarks for example later)
I've worked in raw postscript before and providing I can generate the correct headers etc and file at the end of it I want to avoid use of complex libs that may not do entirely what I want. Some seem to have got bitrot and no longer supported (pypdf and pypdf2) Especially when I know PDF/Postscript can do exactly what I need. PDF content really isn't that complex.
I can generate EPS (Encapsulated postscript) fine by just writing the appropriate text headers to file and my postscript code. But Inspecting PDF's there is a lil binary header I'm not sure how to generate.
I could generate an EPS and convert it. I'm not overly happy with this as the production environment is a Windows 2008 server (Dev is Ubuntu 12.04) and making something and converting it seems very silly.
Has anyone done this before?
Am I being pedantic by not wanting to use a library?

borrowed from ask.yahoo
A PDF file starts with "%PDF-1.1" if it is a version 1.1 type of PDF file. You can read PDF files ok when they don't have binary data objects stored in them, and you could even make one using Notepad if you didn't need to store a binary object like a Paint bitmap in it.
But after seeing the "%PDF-1.1" you ignore what's after that (Adobe Reader does, too) and go straight to the end of the file to where there is a line that says "%%EOF". That's always the last thing in the file; and if that's there you know that just a few characters before that place in the file there's the word "startxref" followed by a number. This number tells a reader program where to look in the file to find the start of the list of items describing the structure of the file. These items in the list can be page objects, dictionary objects, or stream objects (like the binary data of a bitmap), and each one has "obj" and "endobj" marking out where its description starts and ends.
For fairly simple PDF files, you might be able to type the text in just like you did with Notepad to make a working PDF file that Adobe Reader and other PDF viewer programs could read and display correctly.
Doing something like this is a challenge, even for a simple file, and you'd really have to know what you're doing to get any binary data into the file where it's supposed to go; but for character data, you'd just be able to type it in. And all of the commands used in the PDF are in the form of strings that you could type in. The hardest part is calculating those numbers that give the file offsets for items in the file (such as the number following "startxref").
If the way the file format is laid out intrigues you, go ahead and read the PDF manual, which tells the whole story.
http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/PDF32000_2008.pdf
but really you should probably just use a library
Thanks to #LukasGraf for providing this link http://www.gnupdf.org/Introduction_to_PDF that shows how to create a simple hello world pdf from scratch

As long as you're working in Python 2.7, Reportlab seems to be the best solution out there at the moment. It's quite full-featured, and can be a little complex to work with, depending on exactly what you're doing with it, but since you seem to be familiar with PDF internals in general hopefully the learning curve won't be too steep.

I recommend you to use a library. I spent a lot of time creating pdfme and learned a lot of things along the way, but it's not something you would do for a single project. If you want to use my library check the docs here.

How to parse a .shp file?

I am interested in gleaning information from an ESRI .shp file.
Specifically the .shp file of a polyline feature class.
When I open the .dbf of a feature class, I get what I would expect: a table that can open in excel and contains the information from the feature class' table.
However, when I try to open a .shp file in any program (excel, textpad, etc...) all I get is a bunch of gibberish and unusual ASCII characters.
I would like to use Python (2.x) to interpret this file and get information out of it (in this case the vertices of the polyline).
I do not want to use any modules or non built-in tools, as I am genuinely interested in how this process would work and I don't want any dependencies.
Thank you for any hints or points in the right direction you can give!

Your question, basically, is "I have a file full of data stored in an arbitrary binary format. How can I use python to read such a file?"
The answer is, this link contains a description of the format of the file. Write a dissector based on the technical specification.

If you don't want to go to all the trouble of writing a parser, you should take look at pyshp, a pure Python shapefile library. I've been using it for a couple of months now, and have found it quite easy to use.
There's also a python binding to shapelib, if you search the web. But I found the pure Python solution easier to hack around with.

might be a long shot, but you should check out ctypes, and maybe use the .dll file that came with a program (if it even exists lol) that can read that type of file. in my experience, things get weird when u start digging around .dlls

create office files from python

We have a project in python with django.
We need to generate complex word, excel and pdf files.
For the rest of our projects which were done in PHP we used PHPexcel ,
PHPWord and tcpdf for PDF.
What libraries for python would you recommend for creating this kind of files ? (for excel and word its imortant to use the open xml file format xlsx , docx)

Python-docx may help ( https://github.com/mikemaccana/python-docx ).
Python doesn't have highly-developed tools to manipulate word documents. I've found the java library xdocreport ( https://code.google.com/p/xdocreport/ ) to be the best by far for Word reporting. Because I need to generate PCL, which is efficiently done via FOP I also use docx4j.
To integrate this with my python, I use the spark framework to wrap it up with a simple web service, and use requests on the python side to talk to the service.

For excel, there's openpyxl, which actually is a python port of PHPexcel, afaik. I haven't used it yet, but it sounds ok to me.

I would recommend using Docutils. It takes reStructuredText files and converts them to a range of output files. Included in the package are HTML, LaTeX and .odf file writers but in the sandbox there are a whole load of other writers for writing to other formats, see for example, the WordML writer (disclaimer: I haven't used it).
The advantage of this solution is that you can write plain text (reStructuredText) master files, which are human readable as is, and then convert to a range of other file formats as required.
Whilst not a Python solution, you should also look at Pandoc a Haskell library which supports a much wider range of output and input formats than docutils. One major advantage of Pandoc over Docutils is that you can do the reverse translation, i.e. WordML to reStructuredText. You can try Pandoc here.

I have never used any libraries for this, but you can change the extension of any docx, xlsx file to zip, and see the magic!
Generating openxml files is as simple as generating couple of XML files (you can use templates) and zipping it.

Simplest way to generate PDF is to generate HTML (with CSS+images) and convert it using wkhtmltopdf tool.

Is there a standard way, across operating systems, of adding "tags" to files

I'm writing a script to make backups of various different files. What I'd like to do is store meta information about the backup. Currently I'm using the file name, so for example:
backups/cool_file_bkp_c20120119_104955_d20120102
Where c represents the file creation datetime, and d represents "data time" which represents what the cool_file actually contains. The reason I currently use "data time" is that a later backup may be made of the same file, in which case, I know I can safely replace the previous backup of the same "data time" without loosing any information.
It seems like an awful way to do things, but it does seem to have the benefit of being non-os dependent. Is there a better way?
FYI: I am using Python to script my backup creation, and currently need to have this working on Windows XP, 2003, and Redhat Linux.
EDIT: Solution:
From the answers below, I've inferred that metadata on files is not widely supported in a standard way. Given my goal was to tightly couple the metadata with the file, it seems that archiving the file alongside a metadata textfile is the way to go.

I'd take one of two approaches there:
create a stand alone file, on the backub dir, that would contain the desired metadata - this could be somethnng in human readable form, just to make life easier, such as a json data structure, or "ini" like file.
The other one is to archive the copied files - possibily using "zip", and bundle along with it a textual file with the desired meta-data.
The idea of creating zip archives to group files that you want together is used in several places, like in java .jar files, Open Document Format (offfice files created by several office sutres), Office Open XML (Microsoft specific offic files), and even Python language own eggs.
The ziplib module in Python's standard library has all the toools necessary to acomplish this - you can just use a dictionary's representation in a file bundled with the original one to have as much metadata as you need.
In any of these approaches you will also need a helper script to letyou see and filter the metadata on the files, of course.

Different file systems (not different operating systems) have different capabilities for storing metadata. NTFS has plenty of possibilities, while FAT is very limited, and ext* are somewhere in between. None of widespread (subjective term, yes) filesystems support custom tags which you could use. Consequently there exists no standard way to work with such tags.
On Windows there was an attempt to introduce Extended Attributes, but these were implemented in such a tricky way that were almost unusable.
So putting whatever you can into the filename remains the only working approach. Remember that filesystems have limitations on file name and file path length, and with this approach you can exceed the limit, so be careful.