[Tutor] Unzipping a Zip of folders that have zips within them that I'd like to unzip all at once.

[Gregory Lund]

I teach at a college and I'm trying to use Python (2.6 because I'm
running my tool in ArcGIS) to unzip a .zip file that contains one
folder full of student folders, each with 1 or more submissions
(zipfiles) that represent student submissions to weekly lab
assignments.

It all starts with an originalzip.zip (for example) that has a single
folder (originalfolder)
Within the 'originalfolder' folder there are anywhere from 1 - 40
folders (that are not zipped). (these are the students userid folders)
Within each of the (1-40) student userid folders is anywhere from 1-10
zipfiles and perhaps a .pdf or .docx (if for example they submitted
more than one revision of the assignment, there are more than 1)

Folder Structure

originalzip.zip
--originalfolder
  --folder1 (w/ two zip folders)
    --internalzip1_a.zip
    --internalfolder1_a
      --files
      --folders
    --internalzip1_b.zip
    --internalfolder1_b
      --files
      --folders
  --folder2 (w/1 zip folder)
    --internalzip2.zip
    --internalfolder2
      --files
      --folders
  --etc....

My goal is to:
a) Unzip the 'originalzip.zip'
b) go to the 'originalfolder' (the unzipped version of the originalzip.zip)
c) go into the first folder (folder1) in the original folder and unzip
any and all zipfiles within it
d) go to the second folder (folder2) in the original folder and unzip
any and all zipfiles within it
e) continue until all folders within originalfolders have been checked
for internalzips


### Note, I am a beginner both with this tutor environment and in python.
I apologize in advance if my code below is 'not up to par' but I am
trying to keep it simple in nature and use ample comments to keep
track of what I am doing. I also don't know if I should post sample
data (zipfile of a folder of folders with zipfiles), and if so, where?

I have some code that works to extract the 'originalzip.zip', to an
'originalfolder' but it won't go to the folders (folder1, folder2,
etc.) to unzip the zipfiles within them.
It gets hung up on access to the first student folder and won't unzip it.
I think it's a simple fix, but I've been messing with it for quite a
while and can't figure it out.

Code below:

#1 Required imports.
import os, os.path, zipfile, arcpy

#2 I'm Utilizing 'GetParameterAsText' so that this code can be run as
a tool in ArcGIS

#2.1 in_zip is a variable for "What zipfile (LAB) do you want to extract?"
in_Zip = arcpy.GetParameterAsText(0)
cZ = in_Zip

#2.2 outDir is a variable for "What is your output Directory?"
outDir = os.getcwd()

#3 Extracting the initial zipfolder:
#3.1 Opening the original zipfile
z = zipfile.ZipFile(cZ)

#4 Extracting the cZ (original zipfile)into the output directory.
z.extractall(outDir)

#5 Getting a list of contents of the original zipfile
zipContents = z.namelist()

#6 Unzipping the Inner Zips:

#6.1 Looping through the items that were in the original zipfile, and
now in a folder...
#   ...For each item in the zipContents....
for item in zipContents:

    #6.2 Get the location (note the location is the 'outDir' plus what
namelist() gave me)
    #(have never used 'os.sep', had to look it up, when someone suggested it)
    itemLoc = outDir + os.sep + item

    #6.3 Opens the first (2nd, 3rd, etc files) of the internal zip file (*.zip)
    z = zipfile.ZipFile(itemLoc)

    #6.4 Extract all files in *.zip in the same folder as the zipfile
    z.extractall(os.path.split(itemLoc)[0])

    #6.5 determining the list of items in each students' folder
    student_lab = z.namelist()

#7 THE END.

Thank you for any and all suggestions/ fixes, constructive criticism
and assistance with my beginner code!

If you'd like to email me directly it's gwlgis at uw.edu

Regards,
Greg Lund