I'm working on a Python script that reads in a CSV writes the contents out to an Oracle database using cx_Oracle. So far I've been getting the following error:
UnicodeEncodeError: 'ascii' codec can't encode character '\xa0' in position 1369: ordinal not in range(128)
Evidently, cx_Oracle is trying to convert a Unicode character to ASCII and it's not working.
A few clarifying points:
I'm using Python 3.4.3
The CSV file is encoded in UTF-8 and is being opened like open('all.csv', encoding='utf8')
I'm using NVARCHAR2 fields for text in the database and the NLS_NCHAR_CHARACTERSET is set to AL16UTF16. The NLS_CHARACTERSET is WE8MSWIN1252 but from what I understand that shouldn't be relevant since I'm using NVARCHAR2.
I've tried setting the NLS_LANG environment variable to things like .AL16UTF16, _.AL16UTF16 and AMERICAN_AMERICA.WE8MSWIN1252 per this post, but I still get the same error.
Given that I'm reading a UTF-8 file and trying to write to a Unicode-encoded table, can anyone think of why cx_Oracle would still be trying to convert my data to ASCII?
I'm able to produce the error with this code:
field_map = {
...
}
with open('all.csv', encoding='utf8') as f:
reader = csv.DictReader(f)
out_rows = []
for row in reader:
if i == 1000:
break
out_row = {}
for field, source_field in field_map.items():
out_val = row[source_field]
out_row[field] = out_val
out_rows.append(out_row)
i += 1
out_db = datum.connect('oracle-stgeom://user:pass#db')
out_table = out_db['service_requests']
out_table.write(out_rows, chunk_size=10000)
The datum module is a data abstraction library I'm working on. The function responsible for writing to Oracle table is found here.
The full traceback is:
File "C:\Projects\311\write.py", line 64, in <module>
out_table.write(out_rows, chunk_size=10000)
File "z:\datum\datum\table.py", line 89, in write
self._child.write(rows, from_srid=from_srid, chunk_size=chunk_size)
File "z:\datum\datum\oracle_stgeom\table.py", line 476, in write
self._c.executemany(None, val_rows)
UnicodeEncodeError: 'ascii' codec can't encode character '\xa0' in position 1361: ordinal not in range(128)
Check the value of the "encoding" and "nencoding" attributes on the connection. This value is set by calling OCI routines that check the environment variables NLS_LANG and NLS_NCHAR. It looks like this value is US-ASCII or equivalent. When writing to the database, cx_Oracle takes the text and gets a byte string by encoding in the encoding the Oracle client is expecting. Note that this is unrelated to the database encoding. In general, for best performance, it is a good idea to match the database and client encodings -- but if you don't, Oracle will quite happily convert between the two, provided all of the characters used can be represented in both character sets!
Note that if the value of NLS_LANG is invalid it is essentially ignored. AL16UTF16 is one such invalid entry! So set it to the value you would like (such as .AL32UTF8) and check the value of encoding and nencoding on the connection until you get what you want.
Note as well that unless you state otherwise, all strings bound via cx_Oracle to the database are assumed to be in the normal encoding, not the NCHAR encoding. You can override this by using cursor.setinputsizes() and specifying that the input type is NCHAR, FIXED_NCHAR or LONG_NCHAR.
Related
In my code I used something like file = open(path +'/'+filename, 'wb') to write the file
but in my attempt to support non-ascii filenames, I encode it as such
naming = path+'/'+filename
file = open(naming.encode('utf-8', 'surrogateescape'), 'wb')
write binary data...
so the file is named something like directory/path/\xd8\xb9\xd8\xb1\xd8\xa8\xd9.txt
and it works, but the issue arises when I try to get that file again by crawling into the same directory using:
for file in path:
data = open(file.as_posix(), 'rb)
...
I keep getting this error 'ascii' codec can't encode characters in position..
I tried converting the string to bytes like data = open(bytes(file.as_posix(), encoding='utf-8'), 'rb') but I get 'utf-8' codec can't encode characters in position...'
I also tried file.as_posix().encode('utf-8', 'surrogateescape'), I found that both encode and print just fine but with open() I still get the error 'utf-8' codec can't encode characters in position...'
How can I open a file with a utf-8 filename?
I'm using Python 3.9 on ubuntu linux
Any help is greatly appreciated.
EDIT
I figured out why the issue happens when crawling to the directory after writing.
So, when I write the file and give it the raw string directory/path/\xd8\xb9\xd8\xb1\xd8\xa8\xd9.txt and encode the string to utf, it writes fine.
But when finding the file again by crawling into the directory the str(filepath) or filepath.as_posix() returns the string as directory/path/????????.txt so it gives me an error when I try to encode it to any codec.
Currently I'm investigating if the issue's related to my linux locale, it was set to POSIX, I changed it to C.UTF-8 but still no luck atm.
More context: this is a file system where the file is uploaded through a site, so I receive the filename string in utf-8 format
I don't understand why you feel you need to recode filepaths.
Linux (unix) filenames are just sequences of bytes (with a couple of prohibited byte values). There's no need to break astral characters in surrogate pairs; the UTF-8 sequence for an astral character is perfectly acceptable in a filename. But creating surrogate pairs is likely to get you into trouble, because there's no UTF-8 encoding for a surrogate. So if you actually manage to create something that looks like the UTF-8 encoding for a surrogate codepoint, you're likely to encounter a decoding error when you attempt to turn it back into a Unicode codepoint.
Anyway, there's no need to go to all that trouble. Before running this session, I created a directory called ´ñ´ with two empty files, 𝔐 and mañana. The first one is an astral character, U+1D510. As you can see, everything works fine, with no need for manual decoding.
>>> [*Path('ñ').iterdir()]
[PosixPath('ñ/𝔐'), PosixPath('ñ/mañana')]
>>> Path.mkdir('ñ2')
>>> for path in Path('ñ').iterdir():
... open(Path('ñ2', path.name), 'w').close()
...
>>> [*Path('ñ2').iterdir()]
[PosixPath('ñ2/𝔐'), PosixPath('ñ2/mañana')]
>>> [open(path).read() for path in Path('ñ2').iterdir()]
['', '']
Note:
In a comment, OP says that they had previously tried:
file = open('/upload/\xd8\xb9\xd8\xb1\xd8\xa8\xd9\x8a.png', 'wb')
and received the error
UnicodeEncodeError: 'ascii' codec can't encode characters in position 8-11: ordinal not in range(128)
Without more details, it's hard to know how to respond to that. It's possible that open will raise that error for a filesystem which doesn't allow non-ascii characters, but that wouldn't be normal on Linux.
However, it's worth noting that the string literal
'/upload/\xd8\xb9\xd8\xb1\xd8\xa8\xd9\x8a.png'
is not the string you think it is. \x escapes in a Python string are Unicode codepoints (with a maximum value of 255), not individual UTF-8 byte values. The Python string literal, "\xd8\xb9" contains two characters, "O with stroke" (Ø) and "superscript 1" (¹); in other words, it is exactly the same as the string literal "\u00d8\u00b9".
To get the Arabic letter ain (ع), either just type it (if you have an Arabic keyboard setting and your source file encoding is UTF-8, which is the default), or use a Unicode escape for its codepoint U+0639: "\u0639".
If for some reason you insist on using explicit UTF-8 byte encoding, you can use a byte literal as the argument to open:
file = open(b'/upload/\xd8\xb9\xd8\xb1\xd8\xa8\xd9\x8a.png', 'wb')
But that's not recommended.
So after being in a rabbit hole for the past few days, I figured the issue isn't with python itself but with the locale that my web framework was using. Debugging this, I saw that
import sys
print(sys.getfilesystemencoding())
returned 'ASCII', which was weird considering I had set the linux locale to C.UTF-8 but discovered that since I was running WSGI on Apache2, I had to add locale to my WSGI as such WSGIDaemonProcess my_app locale='C.UTF-8' in the Apache configuration file thanks to this post.
i'm using postman to send an excel file which i am reading in tornado.
Tornado code
self.request.files['1'][0]['body'].decode()
here if i send .csv than, the above code works.
if i send .xlsx file than i am stuck with this error.
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x87 in position 10: invalid start byte
request.files will fetch the file but the type would be byte. so to convert byte to str i've used decode(), which works only for .csv and not for .xlsx
i tried decode('utf-8') but still no luck.
i've tried searching but didn't find any issue mentioning 0x87 problem?
The reason is that the .xlsx file has a different encoding, not utf-8. You'll need to use the original encoding to decode the file.
There's no guaranteed way of finding out the encoding of a file programmatically. I'm guessing you're making this application for general users and so you will keep encountering files with different and unexpected encodings.
A good way to deal with this is by trying to decode using multiple encodings, in case one fails. Example:
encodings = ['utf-8', 'iso-8859-1', 'windows-1251', 'windows-1252']
for encoding in encodings:
try:
decoded_file = self.request.files['1'][0]['body'].decode(encoding)
except UnicodeDecodeError:
# this will run when the current encoding fails
# just ignore the error and try the next one
pass
else:
# this will run when an encoding passes
# break the loop
# it is also a good idea to re-encode the
# decoded files to utf-8 for your purpose
decoded_file = decoded_file.encode("utf8")
break
else:
# this will run when the for loop ends
# without successfully decoding the file
# now you can return an error message
# to the user asking them to change
# the file encoding and re upload
self.write("Error: Unidentified file encoding. Re-upload with UTF-8 encoding")
return
# when the program reaches here, it means
# you have successfully decoded the file
# and you can access it from `decoded_file` variable
Here's a list of some common encodings: What is the most common encoding of each language?
I faced the same issue and this worked for me.
import io
df = pd.read_excel(io.BytesIO(self.request.files['1'][0]['body']))
try this one, following suggestions provided here:
self.request.files['1'][0]['body'].decode('iso-8859-1').encode('utf-8')
I have a large .csv that I'm trying to import into a MySQL database for a Django project. I'm using the django.db library to write raw sql statements such as:
LOAD DATA LOCAL INFILE 'file.csv'...
However, I keep getting the following error:
django.db.utils.OperationalError: (1300, "Hey! Are you out tonight?")
After grepping the .csv for the line, I realised that the error is being caused by this character: 😜; though I'm sure there will be other characters throwing that error after I fix this.
Running:
$ file --mime file.csv
from a terminal, returns:
$ file.csv: text/html; charset=us-ascii
Since the rest of my db is in UTF-8, I tried writing a python script to re-encode it, using .encode('utf-8', 'ignore') hoping that the 'ignore' would remove any symbols that gave it trouble, but it threw:
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe9 in position 825410: invalid continuation byte
The thing is, I don't actually care about inserting 100% of the file into my db. I would rather just insert only the 'safe' lines that don't contain strange characters.
So ideally, I'm looking for a way to modify my LOAD DATA LOCAL INFILE sql statement so it just skips inserting any lines that give it trouble. This is optimal, since I don't want to spend time preprocessing the data.
If that isn't feasible, the next best thing is to remove any troublesome character/lines with a Python script that I could later run from my django app whenever I update my db.
If all else fails, information on how to grep out any characters that aren't UTF-8 friendly that I could write a shell script around would be useful.
For 😜, MySQL must use CHARACTER SET utf8mb4 on the column where you will be storing it, the LOAD DATA, and on the connection.
More Python notes: http://mysql.rjweb.org/doc.php/charcoll#python
E9 does not make sense. The hex for the UTF-8 encoding for 😜 is F09F989C.
The link on converting between character is irrelevant; only UTF-8 can be used for Emoji.
Not 100% sure if this will help but this is what I'd try:
Since open() is used to open a CSV file for reading, the file will by default be decoded into unicode using the system default encoding (see locale.getpreferredencoding()). To decode a file using a different encoding, use the encoding argument of open:
import csv
with open('some.csv', newline='', encoding='utf-8') as f:
reader = csv.reader(f)
for row in reader:
print(row)
That's an example gathered from official docs. Have in mind that you might need to replace utf-8 with the actual file encoding, as docs say. Then you can either continue using python to push your data into DB or write a new file with a new encoding.
Alternatively, this could could be another approach.
This question already has answers here:
How to determine the encoding of text
(16 answers)
Closed 6 years ago.
I have a CSV file that I'm uploading via an HTML form to a Python API
The API looks like this:
#app.route('/add_candidates_to_db', methods=['GET','POST'])
def add_candidates():
file = request.files['csv_file']
x = io.StringIO(file.read().decode('UTF8'), newline=None)
csv_input = csv.reader(x)
for row in csv_input:
print(row)
I found the part of the file that causes the issue. In my file it has Í character.
I get this error: UnicodeDecodeError: 'utf8' codec can't decode byte 0xea in position 1317: invalid continuation byte
I thought I was decoding it with .decode('UTF8') or is the error happening before that with file.read()?
How do I fix this?
**
**
Edit: I have control of the file. I am creating the CSV file myself by pulling data (sometimes this data has strange characters).
One the server side, I'm reading each row in the file and inserting into a database.
Your data is not UTF-8, it contains errors. You say that you are generating the data, so the ideal solution is to generate better data.
Unfortunately, sometimes we are unable to get high-quality data, or we have servers that give us garbage and we have to sort it out. For these situations, we can use less strict error handling when decoding text.
Instead of:
file.read().decode('UTF8')
You can use:
file.read().decode('UTF8', 'replace')
This will make it so that any “garbage” characters (anything which is not correctly encoded as UTF-8) will get replaced with U+FFFD, which looks like this:
�
You say that your file has the Í character, but you are probably viewing the file using an encoding other than UTF-8. Is your file supposed to contain Í, or is it just mojibake? Maybe you can figure out what the character is supposed to be, and from that, you can figure out what encoding your data uses if it's not UTF-8.
It seems that your file is not encoded in utf8. You can try reading the file with all the encodings that Python understand and check which lets you read the entire content of the file. Try this script:
from codecs import open
encodings = [
"ascii",
"big5",
"big5hkscs",
"cp037",
"cp424",
"cp437",
"cp500",
"cp720",
"cp737",
"cp775",
"cp850",
"cp852",
"cp855",
"cp856",
"cp857",
"cp858",
"cp860",
"cp861",
"cp862",
"cp863",
"cp864",
"cp865",
"cp866",
"cp869",
"cp874",
"cp875",
"cp932",
"cp949",
"cp950",
"cp1006",
"cp1026",
"cp1140",
"cp1250",
"cp1251",
"cp1252",
"cp1253",
"cp1254",
"cp1255",
"cp1256",
"cp1257",
"cp1258",
"euc_jp",
"euc_jis_2004",
"euc_jisx0213",
"euc_kr",
"gb2312",
"gbk",
"gb18030",
"hz",
"iso2022_jp",
"iso2022_jp_1",
"iso2022_jp_2",
"iso2022_jp_2004",
"iso2022_jp_3",
"iso2022_jp_ext",
"iso2022_kr",
"latin_1",
"iso8859_2",
"iso8859_3",
"iso8859_4",
"iso8859_5",
"iso8859_6",
"iso8859_7",
"iso8859_8",
"iso8859_9",
"iso8859_10",
"iso8859_13",
"iso8859_14",
"iso8859_15",
"iso8859_16",
"johab",
"koi8_r",
"koi8_u",
"mac_cyrillic",
"mac_greek",
"mac_iceland",
"mac_latin2",
"mac_roman",
"mac_turkish",
"ptcp154",
"shift_jis",
"shift_jis_2004",
"shift_jisx0213",
"utf_32",
"utf_32_be",
"utf_32_le",
"utf_16",
"utf_16_be",
"utf_16_le",
"utf_7",
"utf_8",
"utf_8_sig",
]
for encoding in encodings:
try:
with open(file, encoding=encoding) as f:
f.read()
print('Seemingly working encoding: {}'.format(encoding))
except:
pass
where file is again the filename of your file.
Using Python 3.4.2, I want to get a part of a website. According to the meta tags, that website is encoded with iso-8859-1. And I want to write one part (along with other parts) to a CSV file.
However, this part contains an undefined character with the hex value 0x8b. In order to preserve the part as good as possible, I want to write it as is into the CSV file. However, Python doesn't let me do it.
Here's a minimal example:
import urllib.request
import urllib.parse
import csv
if __name__ == "__main__":
with open("bytewrite.csv", "w", newline="") as csvfile:
a = b'\x8b' # byte literal by urllib.request
b = a.decode("iso-8859-1")
w = csv.writer(csvfile)
w.writerow([b])
And this is the output:
Traceback (most recent call last):
File "D:\Eigene\Dateien\Code\Python\writebyte.py", line 12, in <module>
w.writerow([b])
File "C:\Python34\lib\encodings\cp1252.py", line 19, in encode
return codecs.charmap_encode(input,self.errors,encoding_table)[0]
UnicodeEncodeError: 'charmap' codec can't encode character '\x8b' in position 0: character maps to <undefined>
Eventually, I did it manually. It was just copy and paste with Notepad++, and according to a hex editor the value was inserted correctly. But how can I do it with Python 3? Why does Python even care what 0x8b stands for, instead of just writing it to the file?
It further irritates me that according to iso8859_1.py (and also cp1252.py) in C:\Python34\lib\encodings\ the lookup table seems to not interfere:
# iso8859_1.py
'\x8b' # 0x8B -> <control>
# cp1252.py
'\u2039' # 0x8B -> SINGLE LEFT-POINTING ANGLE QUOTATION MARK
Quoted from csv docs:
Since open() is used to open a CSV file for reading, the file will by
default be decoded into unicode using the system default encoding (see
locale.getpreferredencoding()). To decode a file using a different
encoding, use the encoding argument of open:
import csv
with open('some.csv', newline='', encoding='utf-8') as f:
reader = csv.reader(f)
for row in reader:
print(row)
The same applies to writing in something other than the system default encoding: specify the encoding argument when opening the output file.
What is happening is you've decoded to Unicode from iso-8859-1, but getpreferredencoding() returns cp1252 and the Unicode character \x8b is not supported in that encoding.
Corrected minimal example:
import csv
with open('bytewrite.csv', 'w', encoding='iso-8859-1', newline='') as csvfile:
a = b'\x8b'
b = a.decode("iso-8859-1")
w = csv.writer(csvfile)
w.writerow([b])
Your interpretation of the lookup tables in encodings is not correct. The code you've listed:
# iso8859_1.py
'\x8b' # 0x8B -> <control>
# cp1252.py
'\u2039' # 0x8B -> SINGLE LEFT-POINTING ANGLE QUOTATION MARK
Tells you two things:
How to map the unicode character '\x8b' to bytes in iso8859-1, it's just a control character.
How to map the unicode character '\u2039' to bytes in cp1252, it's a piece of punctuation: ‹
This does not tell you how to map the unicode character '\x8b' to bytes in cp1252, which is what you're trying to do.
The root of the problem is that "\x8b" is not a valid iso8859-1 character. Look at the table here:
http://en.wikipedia.org/wiki/ISO/IEC_8859-1#Codepage_layout
8b is undefined, so it just decodes as a control character. After it's decoded and we're in unicode land, what is 0x8b? This is a little tricky to find out, but it's defined in the unicode database here:
008B;<control>;Cc;0;BN;;;;;N;PARTIAL LINE FORWARD;;;;
Now, does CP1252 have this control character, "PARTIAL LINE FORWARD"?
http://en.wikipedia.org/wiki/Windows-1252#Code_page_layout
No, it does not. So you get an error when trying to encode it in CP1252.
Unfortunately there's no good solution for this. Some ideas:
Guess what encoding the page actually is. It's probably CP1252, not ISO-8859-1, but who knows. It could even contain a mix of encodings, or incorrectly encoded data (mojibake). You can use chardet to guess the encoding, or force this URL to use CP1252 in your program (overriding what the meta tag says), or you could try a series of codecs and take the first one that decodes & encodes successfully.
Fix up the input text or the decoded unicode string using some kind of mapping of problematic characters like this. This will work most of the time, but will fail silently or do something weird if you're trying to "fix up" data where it doesn't make sense.
Do not try to convert from ISO-8859-1 to CP1252, as they aren't compatible with each other. If you use UTF-8 that might work better.
Use an encoding error handler. See this table for a list of handlers. Using xmlcharrefreplace and backslashreplace will preserve the information (but then require you to do extra steps when decoding), while replace and ignore will silently skip over the bad character.
These types of issues caused by older encodings are really hard to solve, and there is no perfect solution. This is the reason why unicode was invented.