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How to access remote and encrypted PDF text without writing to local drive [closed]

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I am very new to the coding world and have been stuck on this one problem for 3 days now, searching everywhere for an answer, so any help will be greatly appreciated. I am needing to extract a small amount of text from a url-located Pdf file. I'm using sessions.get(chart_PDF) as the driver for locating the URL where chart_PDF is the example url below.
Example url is https://www.airservicesaustralia.com/aip/pending/dap/PADGN01-166_09SEP2021.pdf
I know I am able to write it to my local drive but I don't want to do that, I want to be able to do it remotely, since I only need a couple of numbers from it.
I have tried finding the password from the url page for decrypting, couldn't find. I've tried to use PyPDF2, pdfminer and pikepdf (probably not well).
I only need to retrieve two numbers near the bottom of the PDF that can be used for the rest of my code. Please help, even if it is a simple fix, I'm new to all this and need some help. Thanks.
from io import BytesIO
from pikepdf import Pdf as PDF
from pdfminer import high_level
chart_PDF = https://www.airservicesaustralia.com/aip/pending/dap/PADGN01-166_09SEP2021.pdf
retrieve = s.get(chart_PDF)
content = retrieve.content
response =urllib.request.urlopen(chart_PDF)
p = BytesIO(content)
p.getbuffer()
check = PDFPage.get_pages(p, check_extractable=False)
extract = high_level.extract_text(p)
I'm getting:
PDFTextExtractionNotAllowedWarning: The PDF <_io.BytesIO object at 0x000001B007ABEC20> contains a metadata field indicating that it should not allow text extraction. Ignoring this field and proceeding.warnings.warn(warning_msg, PDFTextExtractionNotAllowedWarning)
Alternately, if I try this:
from pikepdf import Pdf as PDF
from pdfminer.pdfpage import PDFPage
from PyPDF2 import PdfFileReader
new_pdf = PDF.new()
with PDF.open(p) as pdf:
print(len(pdf.pages))
page1 = pdf.pages[0]
if PdfFileReader.getIsEncrypted(pdf):
print(True)
PdfFileReader.decrypt(page1, password='')
pdf.close()
I get:
line 1987, in decrypt
return self._decrypt(password)
AttributeError: _decrypt
UPDATE 3/8/21
Thank you so much K J! You've seriously been a huge help!
from io import BytesIO
from pdfminer.pdfpage import PDFPage
from pdfminer import high_level
retrieve = s.get(chart_PDF)
content = retrieve.content
bytes = BytesIO(content)
bytes.getbuffer()
PDFPage.get_pages(bytes, check_extractable=False)
extract = high_level.extract_text(bytes, password='') #THIS LINE THROWS ERROR
joined = ''.join(extract)
find_txt = re.findall(r'[(]\d*[-]\d[.]\d[)]', joined)
print(find_txt)
bytes.close()
This is now working well and I have been able to pull the numbers that I need (I have basically pulled all numbers from inside brackets off the PDF). I'll sort through that to find which one I need.
Strangely enough, although its giving me what I need, my extract = high_level.extract_text(bytes, password='') line still throws the Warning: (warning_msg, PDFTextExtractionNotAllowedWarning) which is rather annoying. Not sure how this process works but its still letting the info out.
I can't use try except or it skips over it. What is the way around this? how can I stop that error coming up?
FINAL UPDATE
I got around the warning and it works well now.
with warnings.catch_warnings():
warnings.simplefilter("ignore")
extract = high_level.extract_text(bytes)
Cheers fellas for putting up with my ignorance, you've helped so much.

The whole file has to be downloaded to a device via RAM so the blob as a FILE can be parsed at the very END for one OR more %%EOF and the location of page 0 (it gets converted to 1 or i) it could be ANYWHERE IN THE STREAM,.
THEN you can navigate to other sequential numbered pages in the RANDOM order they are built. Any complaints please contact Adobe.
However it is easiest if it is cached as a physical FILE object. If you dont want that on disk use a ram drive for your browser.
Again those two objects at bottom of page one could be anywhere mixed into the content of "page" 99's objects, or otherwise. each letter in a PDF can in its extreme be more than one object anywhere in the file. but a good authoring editor would try to keep them as lines by lines. (there is no such PDF thing as a word or paragraph.)
We can Print the file as Plain Text to see how it is composited and although (secured) that is allowed.
I tried printing from browser with little success but know that can depend on browser system and OS print drivers. Here I have printed the page as text using Acrobat portable, so we can see the sequential offsets of each text block from Left Hand margin JUST LIKE a PDF VIEWER would need to rebuild them.
UPDATE
You said your target is (1380-4.4) to the RIGHT of ALTERNATE but again A PDF has no concept of Left and Right or BEFORE or AFTER so we find IN THIS FILE the variable target is in 2 separate pieces PRIOR to the KNOWN characters which luckily is a complete single block (alternate). Thus here proximity of plain text could well work if the capture is confined to that nearby locality. However there is no guarantee that ALTERNATE would always be a single block.
It was perhaps not a good Idea To show the way a Printer would be given a stream of sequential data
Here is the way one PDF viewer goes about decrypting the file
As stated on this occasion the word ALTERNATE is defined as text however the next item is the "3" under "B" which is text as a vector path it is not called a "character" although it looks like one but a numbered glyph from a font table. We do see later that some of those numbers are stored as "text" and for your target it is mixed in with similar text in the same object.
Thus you need to call a PDF interpreter to give you a meaningful translation of all bits and pieces of objects so that you can extract the "right" text.
The easiest way for a "simple" one line target in a complex file is to use MuPDF to first tidy up the file
mutool clean -gggg -D infile.pdf outfile.pdf
combined with
PDFTOTXT -layout outfile.pdf outfile.txt
or similar to hopefully export that text on a line by line basis, such that you can consistently find your target instantly before ! or after ALTERNATE.
N.B Mutool convert to HTML would place the target value in a table entry AFTER the key word, and if the lines are consistent in number that would be a simpler way to find or grep.

Wrong character encoding of rtf file

When I copy and paste the sentence How brave they’ll all think me at home! into a blank TextEdit rtf document on the Mac, it looks fine. But if I create an an apparently identical rtf file programatically, and write the same sentence into it, on opening TextEdit it appears as How brave they’ll all think me at home! In the following code, output is OK, but the file when viewed in TextEdit has problems with the right single quotation mark (here used as an apostrophe), unicode U-2019.
header = r"""{\rtf1\ansi\ansicpg1252\cocoartf1671\cocoasubrtf400
{\fonttbl\f0\fswiss\fcharset0 Helvetica;}
{\colortbl;\red255\green255\blue255;}
{\*\expandedcolortbl;;}
\paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
\pard\tx720\tx1440\tx2160\tx2880\tx3600\tx4320\tx5040\tx5760\tx6480\tx7200\tx7920\tx8640\pardirnatural\partightenfactor0
\f0\fs24 \cf0 """
sen = 'How brave they’ll all think me at home!'
with open('staging.rtf', 'w+’) as f:
f.write(header)
f.write(sen)
f.write('}')
with open('staging.rtf') as f:
output = f.read()
print(output)
I’ve discovered from https://www.i18nqa.com/debug/utf8-debug.html that this may be caused by “UTF-8 bytes being interpreted as Windows-1252”, and that makes sense as it seems that ansicpg1252 in the header indicates US Windows.
But I still can’t work out how to fix it, even having read the similar issue here: Encoding of rtf file. I’ve tried replacing ansi with mac without effect. And adding ,encoding='utf8' to the open function doesn’t seem to help either.
(The reason for using rtf by the way is to be able to export sentences with colour-coded words, allow them to be manually edited, then read back in for further processing).

OK, I've found the answer myself. I needed to use , encoding='windows-1252' both when writing to the rtf file and also when reading from it.

Write to an HTML file with Python

I have a couple of graphs I need to display in my browser offline, MPLD3 outputs the html as a string and I need to be able to make an html file containing that string. What I'm doing right now is:
tohtml = mpld3.fig_to_html(fig, mpld3_url='/home/pi/webpage/mpld3.js',
d3_url='/home/pi/webpage/d3.js')
print(tohtml)
Html_file = open("graph.html","w")
Html_file.write(tohtml)
Html_file.close();
tohtml is the variable where the HTML string is stored. I've printed this string to the terminal and then pasted it into an empty HTML file and I get my desired result. However, when I run my code, I get an empty file named graph.html

It seems like you may be reinventing the wheel here. Have you tried something like,
mpld3_url='/home/pi/webpage/mpld3.js'
d3_url='/home/pi/webpage/d3.js'
with open('graph.html', 'w') as fileobj:
mpld3.save_html(fig, fileobj, d3_url=d3_url, mpld3_url=mpld3_url)
Note, this is untested just going off of mpld3.save_html documentation and using prior knowledge about Python IO Streams

Python 'corrupts' downloaded pdf file

I am writing a program to automatically download a Wikipedia page as pdf, using their embedded tool.
I was able to fix a problem where I wasn't able to retrieve the data from a submit button. The new problem is, that I can download the file (I used open() and also urllib.request.urlretrieve(), but I'm not able to open it manually then.
It seems like the file is being corrupted while being downloaded (I think it's an encoding failure). This disables opening the PDF.. (unsupported datatype or corrupted file=
This is the code I use:
import requests
import urllib.request
base_url = 'https://de.wikipedia.org/wiki/'
def createURL(base):
title = 'Rektifikation (Verfahrenstechnik)'
name = title.replace(" ", "_")
url = (base + name).replace('(', '%28').replace(')', '%29')
print(url)
getPDF(url, title)
def getPDF(url, title):
r = requests.get(url, allow_redirects=True)
open('{}.pdf'.format(title), 'wb').write(r.content)
urllib.request.urlretrieve('https://de.wikipedia.org/w/index.php?title=Spezial:ElectronPdf&page=Rektifikation+%28Verfahrenstechnik%29&action=show-download-screen)', '{}_vl.pdf'.format(title))
createURL(base_url)
I hardcoded most of the stuff for debugging reasons. Feel free to help me improve the code, but note that this isn't my main purpose, please.
My question now is: What could I possibly do to stop the file from getting corrupted (encode it the right way)
This is the link (click the button) I'm trying to download from.
Note: It's an instant download link with a redirect.
Thanks for your help, if you need any more information just ask me.
EDIT: Opening the PDF via Word lets me see, that the data (texts, paragraphs..) is available. So the PDF contains the data and the download itself seems to be successful.
The sizes of the downloaded files differ, maybe someone can have a look at this problem too:
open: 58KB
urllib: 18KB
manually: 239KB

pyPdf unable to extract text from some pages in my PDF

I'm trying to use pyPdf to extract and print pages from a multipage PDF. Problem is, text is not extracted from some pages. I've put an example file here:
http://www.4shared.com/document/kmJF67E4/forms.html
If you run the following, the first 81 pages return no text, while the final 11 extract properly. Can anyone help?
from pyPdf import PdfFileReader
input = PdfFileReader(file("forms.pdf", "rb"))
for page in input1.pages:
print page.extractText()

Note that extractText() still has problems extracting the text properly. From the documentation for extractText():
This works well for some PDF files,
but poorly for others, depending on
the generator used. This will be
refined in the future. Do not rely on
the order of text coming out of this
function, as it will change if this
function is made more sophisticated.
Since it is the text you want, you can use the Linux command pdftotext.
To invoke that using Python, you can do this:
>>> import subprocess
>>> subprocess.call(['pdftotext', 'forms.pdf', 'output'])
The text is extracted from forms.pdf and saved to output.
This works in the case of your PDF file and extracts the text you want.

This isn't really an answer, but the problem with pyPdf is this: it doesn't yet support CMaps. PDF allows fonts to use CMaps to map character IDs (bytes in the PDF) to Unicode character codes. When you have a PDF that contains non-ASCII characters, there's probably a CMap in use, and even sometimes when there's no non-ASCII characters. When pyPdf encounters strings that are not in standard Unicode encoding, it just sees a bunch of byte code; it can't convert those bytes to Unicode, so it just gives you empty strings. I actually had this same problem and I'm working on the source code at the moment. It's time consuming, but I hope to send a patch to the maintainer some time around mid-2011.

You could also try the pdfminer library (also in python), and see if it's better at extracting the text. For splitting however, you will have to stick with pyPdf as pdfminer doesn't support that.

I find it sometimes useful to convert it to ps (try with pdf2psand pdftops for potential differences) then back to pdf (ps2pdf). Then try your original script again.

I had similar problem with some pdfs and for windows, this is working excellent for me:
1.- Download Xpdf tools for windows
2.- copy pdftotext.exe from xpdf-tools-win-4.00\bin32 to C:\Windows\System32 and also to C:\Windows\SysWOW64
3.- use subprocess to run command from console:
import subprocess
try:
extInfo = subprocess.check_output('pdftotext.exe '+filePath + ' -',shell=True,stderr=subprocess.STDOUT).strip()
except Exception as e:
print (e)

I'm starting to think I should adopt a messy two-part solution. there are two sections to the PDF, pp 1-82 which have text page labels (pdftotext can extract), and pp 83-end which have no page labels but pyPDF can extract and it explicitly knows pages.
I think I need to combine the two. Clunky, but I don't see any way round it. Sadly I'm having to do this on a Windows machine.