def filter_ocr(pdf_dir):
"""
Use `pdffonts` to check for PDFs that are just images and would require OCR.
"""
scraper_logging.debug_print("Begin removing PDFs that need OCR...")
count = 0
src_files = os.listdir(pdf_dir)
for pdf in src_files:
if (pdf == ".DS_Store"):
continue
pdf_filename = os.path.join(pdf_dir, pdf)
if (os.path.isfile(pdf_filename)):
try:
output = subprocess.check_output(["pdffonts", pdf_filename],
stderr=subprocess.STDOUT)
except subprocess.CalledProcessError:
# Error usually means we got a HTML file instead of an actual PDF.
scraper_logging.debug_print_verbose(
"pdffonts error on %s. Removing." % pdf_filename)
os.remove(pdf_filename)
count += 1
continue
# output = subprocess.Popen(["pdffonts", pdf_filename], stdout=subprocess.PIPE).communicate()[0]
if (len(output.split('\n')) <= 3):
count += 1
# this has no fonts and thus is an image.
scraper_logging.debug_print_verbose("OCR Filtering: " +
pdf_filename)
os.remove(pdf_filename)
scraper_logging.debug_print("Finished removing %s PDFs that needed OCR." %
count)
def download_csv(csv_dir, fv_code, pages):
"""
Scrape the CSV data from the Digikey website for the specified product family.
"""
data = {
'fv': fv_code, # 'ffe002af' for op-amps
'mnonly': '0',
'newproducts': '0',
'ColumnSort': '0',
'page': '1',
'stock': '0',
'pbfree': '0',
'rohs': '0',
'quantity': '0',
'ptm': '0',
'fid': '0',
'pageSize': '500'
}
scraper_logging.debug_print("Downloading " + str(pages) + " pages...")
for i in range(pages):
# Make a bunch of files since each page starts with the CSV header.
# We don't want random header rows in the CSV file.
filename = csv_dir + fv_code + "_" + str(i) + ".csv"
target = open(filename, 'w')
data['page'] = i + 1
r = requests.get('http://www.digikey.com/product-search/download.csv',
params=data)
target.write(r.text.encode('utf-8'))
target.close()
scraper_logging.debug_print_verbose("Saved CSV: " + filename)
def expected_unique_pdfs(csv_dir):
"""
Count the number of unique datasheet URLs found in the CSV files.
"""
unique_urls = set()
for filename in sorted(os.listdir(csv_dir)):
if filename.endswith(".csv"):
path = os.path.join(csv_dir, filename)
scraper_logging.debug_print_verbose('Counting URLs from %s' % path)
with open(path, 'rb') as csvinput:
reader = csv.reader(csvinput)
next(reader, None) # skip the header row
for row in reader:
# First element of each row is the URL to the PDF
url = row[DATASHEET]
# Right now, we will always filter duplicate PDFs.
if not (url == '-' or url is None):
unique_urls.add(url)
scraper_logging.debug_print("Expected unique PDFs: %d" % len(unique_urls))
def filter_encrypted(pdf_dir):
"""
Remove PDFs that are encrypted, since Acrobat cannot convert them to HTML.
"""
pattern = re.compile(r"Encrypted:\s*yes", re.U)
scraper_logging.debug_print("Begin removing PDFs that are encrypted...")
count = 0
src_files = os.listdir(pdf_dir)
for pdf in src_files:
if (pdf == ".DS_Store"):
continue
pdf_filename = os.path.join(pdf_dir, pdf)
if (os.path.isfile(pdf_filename)):
try:
output = subprocess.check_output(["pdfinfo", pdf_filename],
stderr=subprocess.STDOUT)
except subprocess.CalledProcessError:
# Error usually means we got a HTML file instead of an actual PDF.
scraper_logging.debug_print_verbose(
"pdfinfo error on %s. Removing." % pdf_filename)
os.remove(pdf_filename)
count += 1
continue
# Matching for lines that look like this:
# Encrypted: yes (print:yes copy:yes change:no addNotes:no algorithm:RC4)
if (pattern.search(output)):
count += 1
# this has no fonts and thus is an image.
scraper_logging.debug_print_verbose("Encrypted Filtering: " +
pdf_filename)
os.remove(pdf_filename)
scraper_logging.debug_print(
"Finished removing %s PDFs that were encrypted." % count)
def download_pdf(src, dest):
"""
For each CSV at the 1st level of the src directory, download the datasheet
and save it to the destination directory.
"""
total_count = 0
unique_urls = set()
for filename in sorted(os.listdir(src)):
if filename.endswith(".csv"):
path = os.path.join(src, filename)
scraper_logging.debug_print('Downloading from %s' % path)
with open(path, 'rb') as csvinput:
reader = csv.reader(csvinput)
next(reader, None) # skip the header row
for row in reader:
# First element of each row is the URL to the PDF
url = row[DATASHEET]
# Right now, we will always filter duplicate PDFs.
if url == '-' or url is None or url in unique_urls:
continue
# Append 'http:' if none is found in the url. This is because
# Digikey sometimes has "//media.digikey.com/..." urls.
if not url.startswith("http"):
url = "http:" + url
try:
opener = urllib2.build_opener()
opener.addheaders = [('User-agent', 'Mozilla/5.0')]
response = opener.open(url)
unique_urls.add(url) # track unique urls
# outfile = dest + re.sub('[^A-Za-z0-9]+', '', row[MANUF]) + '_' + re.sub('[^A-Za-z0-9]+', '', row[PARTNUM]) + ".pdf"
path = urlparse.urlsplit(url).path
basename = posixpath.basename(path)
# NOTE: This is to handle the weird filehandler URLs
# such as http://www.microchip.com/mymicrochip/filehandler.aspx?ddocname=en011815
# or https://toshiba.semicon-storage.com/info/docget.jsp?did=11316&prodName=TC75S101F
# Reference: http://stackoverflow.com/questions/862173/how-to-download-a-file-using-python-in-a-smarter-way
if not (basename.endswith('.pdf')
or basename.endswith(".PDF")):
if response.info().has_key('Content-Disposition'):
basename = response.info(
)['Content-Disposition'].split('filename=')[1]
if basename[0] == '"' or basename[0] == "'":
basename = basename[1:-1]
elif url != response.url: # if we were redirected, get filename from new URL
unique_urls.add(
response.url) # track unique urls
path = urlparse.urlsplit(response.url).path
basename = posixpath.basename(path)
basename = re.sub(
'[^A-Za-z0-9\.\-\_]+', '',
basename) # strip away weird characters
outfile = dest + basename # just type the original filename
if not (outfile.endswith('.pdf')
or outfile.endswith(".PDF")):
outfile = outfile + ".pdf"
# Lowercase everything to ensure consistency in extensions and remove more duplicates
outfile = outfile.lower()
scraper_logging.debug_print_verbose(" Saving %s" %
outfile)
pdf_file = open(outfile, 'w')
pdf_file.write(response.read())
pdf_file.close()
total_count += 1
except urllib2.HTTPError, err:
if err.code == 404:
scraper_logging.debug_print_verbose(
" Page not found: %s" % url)
elif err.code == 403:
# These can mostly be avoided by specifying a user-agent
# http://stackoverflow.com/questions/11450649/python-urllib2-cant-get-google-url
scraper_logging.debug_print_verbose(
" Access Denied: %s" % url)
else:
scraper_logging.debug_print_verbose(
" HTTP Error code %s for %s" %
(err.code, url))
continue # advance to next datasheet rather than crashing
except urllib2.URLError:
scraper_logging.debug_print_verbose(
" urllib2.URLError for %s" % url)
continue
except Exception as e:
scraper_logging.debug_print_error(
"Exception %s on URL %s" % (e, url))
continue
time.sleep(
0.1
) # Limit our HTTP Requests rate slightly for courtesy.