I'm trying to use zlib to compress out some lengthy strings, some of which may contain unicode characters. At the moment, I'm doing this in ruby, but I think this would apply across any language really. Here's the super basic implementation:
require 'zlib'
example = "“hello world”" # note the unicode quotes
compressed = Zlib.deflate(example)
puts Zlib.inflate(compressed)
The issue here is that the text comes out as this:
\xE2\x80\x9Chello world\xE2\x80\x9
...no unicode quotes, just weird unrecognizable characters. Does anyone know of a way that Zlib can be used while retaining unicode characters? Bonus points for an answer in ruby : )
It seems Zlib produces ASCII-8BIT as the default encoding upon inflating. To fix it just force the original encoding:
require 'zlib'
input = "“hello world”"
compressed = Zlib.deflate(input)
output = Zlib.inflate(compressed).force_encoding(input.encoding)
Or set the encoding manually:
output = Zlib.inflate(compressed).force_encoding('utf-8')
Related
I have a text file which if viewed in the Scite editor with the encoding set to utf-8, displays all text correctly, including capital letters with an accute accent (i.e. Á).
However, if I write a ruby script and use mystring.encode("utf-8") it will give me this error on capital letters that carry an acute accent (i.e. Á):
encode': "\x81" to UTF-8 in conversion from Windows-1252 to UTF-8 (Encoding::UndefinedConversionError)
Is this expected behaviour? How can I encode the whole text to utf-8 using ruby, knowing that otherwise it does get successfully encoded in the Scite editor?
Code:
ine_file = File.open("../../_data/ine_spain_demographics.csv", 'r')
ine_towns_population_hash = Hash.new
ine_file.each do|line|
values = line.split(";")
town_name = values[3]
population = values[4]
begin
ine_towns_population_hash[town_name.encode("utf-8")] = population
rescue
puts "problematic string: " + town_name
end
end
You say that ine_file.external_encoding says Windows-1252 so the file is being opened as a Windows-1252 encoded file. Then you say town_name.encode("utf-8") in an attempt to encoded a string as UTF-8 and Ruby complains. But the file is actually UTF-8; reading UTF-8 bytes as Windows-1252 and then trying to recode those bytes as UTF-8 isn't going to work.
You need to open the file in UTF-8 mode:
File.open("../../_data/ine_spain_demographics.csv", 'r:UTF-8')
and stop trying to change the encoding of town_name, just use town_name as-is.
It seems like it's misinterpreting the encoding of ine_spain_demographics.csv.
Looking at the doc's for encode and open you have two options:
Use replace in encode to tell Ruby what character to use town_name.encode("utf-8", replace: '').
Identify the correct file encoding and specify it: File.open("../../_data/ine_spain_demographics.csv", 'r:ISO-8859-1')
I am currently trying to write a script that iterates over an input file and checks data on a website. If it finds the new data, it prints out to the terminal that it passes, if it doesn't it tells me it fails. And vice versa for deleted data. It was working fine until the input file I was given contains the "™" character. Then when ruby gets to that line, it is spitting out an error:
PDAPWeb.rb:73:in `include?': incompatible character encodings: UTF-8 and IBM437
(Encoding::CompatibilityError)
The offending line is a simple check to see if the text exists on the page.
if browser.text.include? (program_name)
Where the program_name variable is a parsed piece of information from the input file. In this instance, the program_name contains the 'TM' character mentioned before.
After some research I found that adding the line # encoding: utf-8 to the beginning of my script could help, but so far has not proven useful.
I added this to my program_name variable to see if it would help(and it allowed my script to run without errors), but now it is not properly finding the TM character when it should be.
program_name = record[2].gsub("\n", '').force_encoding("utf-8").encode("IBM437", replace: nil)
This seemed to convert the TM character to this: Γäó
I thought maybe i had IBM437 and utf-8 parts reversed, so I tried the opposite
program_name = record[2].gsub("\n", '').force_encoding("IBM437").encode("utf-8", replace: nil)
and am now receiving this error when attempting to run the script
PDAPWeb.rb:48:in `encode': U+2122 from UTF-8 to IBM437 (Encoding::UndefinedConve
rsionError)
I am using ruby 1.9.3p392 (2013-02-22) and I'm not sure if I should upgrade as this is the standard version installed in my company.
Is my encoding incorrect and causing it to convert the TM character with errors?
Here’s what it looks like is going on. Your input file contains a ™ character, and it is in UTF-8 encoding. However when you read it, since you don’t specify the encoding, Ruby assumes it is in your system’s default encoding of IBM437 (you must be on Windows).
This is basically the same as this:
>> input = "™"
=> "™"
>> input.encoding
=> #<Encoding:UTF-8>
>> input.force_encoding 'ibm437'
=> "\xE2\x84\xA2"
Note that force_encoding doesn’t change the actual string, just the label associated with it. This is the same outcome as in your case, only you arrive here via a different route (by reading the file).
The web page also has a ™ symbol, and is also encoded as UTF-8, but in this case Ruby has the encoding correct (Watir probably uses the headers from the page):
>> web_page = '™'
=> "™"
>> web_page.encoding
=> #<Encoding:UTF-8>
Now when you try to compare these two strings you get the compatibility error, because they have different encodings:
>> web_page.include? input
Encoding::CompatibilityError: incompatible character encodings: UTF-8 and IBM437
from (irb):11:in `include?'
from (irb):11
from /Users/matt/.rvm/rubies/ruby-2.2.1/bin/irb:11:in `<main>'
If either of the two strings only contained ASCII characters (i.e. code points less that 128) then this comparison would have worked. Both UTF-8 and IBM437 are both supersets of ASCII, and are only incompatible if they both contain characters outside of the ASCII range. This is why you only started seeing this behaviour when the input file had a ™.
The fix is to inform Ruby what the actual encoding of the input file is. You can do this with the already loaded string:
>> input.force_encoding 'utf-8'
=> "™"
You can also do this when reading the file, e.g. (there are a few ways of reading files, they all should allow you to explicitly specify the encoding):
input = File.read("input_file.txt", :encoding => "utf-8")
# now input will be in the correct encoding
Note in both of these the string isn’t being changed, it still contains the same bytes, but Ruby now knows its correct encoding.
Now the comparison should work okay:
>> web_page.include? input
=> true
There is no need to encode the string. Here’s what happens if you do. First if you correct the encoding to UTF-8 then encode to IBM437:
>> input.force_encoding("utf-8").encode("IBM437", replace: nil)
Encoding::UndefinedConversionError: U+2122 from UTF-8 to IBM437
from (irb):16:in `encode'
from (irb):16
from /Users/matt/.rvm/rubies/ruby-2.2.1/bin/irb:11:in `<main>'
IBM437 doesn’t include the ™ character, so you can’t encode a string containing it to this encoding without losing data. By default Ruby raises an exception when this happens. You can force the encoding by using the :undef option, but the symbol is lost:
>> input.force_encoding("utf-8").encode("IBM437", :undef => :replace)
=> "?"
If you go the other way, first using force_encoding to IBM437 then encoding to UTF-8 you get the string Γäó:
>> input.force_encoding("IBM437").encode("utf-8", replace: nil)
=> "Γäó"
The string is already in IBM437 encoding as far as Ruby is concerned, so force_encoding doesn’t do anything. The UTF-8 representation of ™ is the three bytes 0xe2 0x84 0xa2, and when interpreted as IBM437 these bytes correspond to the three characters seen here which are then converted into their UTF-8 representations.
(These two outcomes are the other way round from what you describe in the question, hence my comment above. I’m assuming that this is just a copy-and-paste error.)
When I do this:
require 'open-uri'
response = open('some-html-page-url-here')
response.read
On a certain url I get the following error (due to wrong encoding in the returned url?!):
Encoding::UndefinedConversionError: U+00A0 from UTF-8 to US-ASCII
Any way around this to still get the html content?
In the introduction to the open-uri module, the docs say this,
It is possible to open an http, https or ftp URL as though it were a file
And if you know anything about reading files, then you have to know the encoding of the file you are trying to read. You need to know the encoding so that you can tell ruby how to read the file(i.e. how many bytes(or how much space) each character will occupy).
In the first code example in the docs, there is this:
open("http://www.ruby-lang.org/en") {|f|
f.each_line {|line| p line}
p f.base_uri # <URI::HTTP:0x40e6ef2 URL:http://www.ruby-lang.org/en/>
p f.content_type # "text/html"
p f.charset # "iso-8859-1"
p f.content_encoding # []
p f.last_modified # Thu Dec 05 02:45:02 UTC 2002
}
So if you don't know the encoding of the "file" you are trying to read, you can get the encoding with f.charset. If that encoding is different than your default external encoding, you will most likely get an error. Your default external encoding is the encoding ruby uses to read from external sources. You can check what your default external encoding is set to like this:
The default external Encoding is pulled from your environment...Have a
look:
$ echo $LC_CTYPE
en_US.UTF-8
or
$ ruby -e 'puts Encoding.default_external.name'
UTF-8
http://graysoftinc.com/character-encodings/ruby-19s-three-default-encodings
On Mac OSX, I actually have to do the following to see the default external encoding:
$ echo $LANG
You can set your default external encoding with the method Encoding.default_external=(), so you might want to try something like this:
open('some_url_here') do |f|
Encoding.default_external = f.charset
html = f.read
end
Setting an IO object to binmode, like you have done, tells ruby that the encoding of the file is BINARY (or ruby's confusing synonym ASCII-8BIT), which means you are telling ruby that each character in the file takes up one byte. In your case, you are telling ruby to read the character U+00A0, whose UTF-8 representation takes up two bytes 0xC2 0xA0, as two characters instead of just one character, so you have eliminated your error, but you have produced two junk characters instead of the original character.
Doing a response.binmode before the response.read stops the error from happening.
Had the same issue, will add my solution here:
After reading the open-uri documentation further, it turns out you could set the encoding of the io before reading using the set_encoding method, like this:
result = open('some-page-uri') do |io|
io.set_encoding(Encoding.default_external)
io.read
end
Hope it helps!
I try to use search, google but with no luck.
OS: Windows XP
Ruby version 1.9.3po
Error:
`gsub': incompatible character encodings: UTF-8 and IBM437
Code:
require 'rubygems'
require 'hpricot'
require 'net/http'
source = Net::HTTP.get('host', '/' + ARGV[0] + '.asp')
doc = Hpricot(source)
doc.search("p.MsoNormal/a").each do |a|
puts a.to_plain_text
end
Program output few strings but when text is ”NOŻYCE” I am getting error above.
Could somebody help?
You could try converting your HTML to UTF-8 since it appears the original is in vintage-retro DOS format:
source.encode!('UTF-8')
That should flip it from 8-bit ASCII to UTF-8 as expected by the Hpricot parser.
The inner encoding of the source variable is UTF-8 but that is not what you want.
As tadman wrote, you must first tell Ruby that the actual characters in the string are in the IBM437 encoding. Then you can convert that string to your favourite encoding, but only if such a conversion is possible.
source.force_encoding('IBM437').encode('UTF-8')
In your case, you cannot convert your string to ISO-8859-2 because not all IBM437 characters can be converted to that charset. Sticking to UTF-8 is probably your best option.
Anyway, are you sure that that file is actually transmitted in IBM437? Maybe it is stored as such in the HTTP server but it is sent over-the-wire with another encoding. Or it may not even be exactly in IBM437, it may be CP852, also called MS-DOC Latin 2 (different from ISO Latin 2).
I'm writing a Ruby script to process a large text file, and keep getting an odd encoding error.
Here's the situation:
input_data = File.new(in_path, 'r').read
p input_data.encoding.name # UTF-8
break_char = "\r".encode("UTF-8")
p break_char # "\r"
p break_char.encoding.name # "UTF-8"
input_data.split(",".encode("UTF-8"))
p Encoding.compatible?(input_data, break_char) # # Encoding:UTF-8>
This produces the error :in 'split': invalid byte sequence in UTF-8 (ArgumentError)
I read http://blog.grayproductions.net/articles/ruby_19s_string and looked at other solutions to apparently the same problem, but still can't work out why it's happening when I believe I am controlling the encodings.
I'm on OSX working with ruby 1.9.2
Obviously your input file is not UTF-8 (or at least, not entirely). If you don't care about non-ascii characters, you can simply assume your file is ascii-8bit encoded. BTW, your separator (break_char) is not causing problems as comma is encoded the same way in UTF-8 as in ASCII.
fname = 'test.in'
# create example file and fill it with invalid UTF-8 sequence
File.open(fname, 'w') do |f|
f.write "\xc3\x28"
end
# then try to read and parse it
s = File.open(fname) do |f| # file opened as UTF-8
#s = File.open(fname, 'r:ascii-8bit') do |f| # file opened as ascii-8bit
f.read
end
p s.split ','
I fail to get an error here on Linux even when the input file is not UTF-8. (I'm using Ruby 1.9.2, as well.)
Logically, either this problem is linked with OS-X, or it's something to do with your input data. Does it happen regardless of the data in the input file?
(I realise that this is not a proper answer, but I lack the rep to add a comment. And since no-one has responded yet, I thought it better than nothing...)
You read the file using the default encoding your system provides. So ruby tags the string as utf8, which doesn't mean it's really utf8-data. Try file <input file> to guess what kind of encoding is in there, then tell ruby it's that one (unclean: force_encoding(<encoding>), clean: tell the File object what encoding it is, I don't know how to do that) and then use encode!("utf8") to convert it to utf8.
Here are 2 common situations and how to deal with them:
Situation 1
You have an UTF-8 input-file with possibly a few invalid bytes
Remove the invalid bytes:
test = "Partly valid\xE4 UTF-8 encoding: äöüß"
File.open( 'input_file', 'w' ) {|f| f.write(test)}
str = File.read( 'input_file' )
str.scrub('')
=> "Partly valid UTF-8 encoding: äöüß"
Situation 2
You have an input-file that could be in either UTF-8 or ISO-8859-1 encoding
Check which encoding it is and convert to UTF-8 (if necessary):
test = "String in ISO-8859-1 encoding: \xE4\xF6\xFC\xDF"
File.open( 'input_file', 'w' ) {|f| f.write(test)}
str = File.read( 'input_file' )
unless str.valid_encoding?
str.encode!( 'UTF-8', 'ISO-8859-1', invalid: :replace )
end #unless
=> "String in ISO-8859-1 encoding: äöüß"
Notes
The above code snippets assume that Ruby encodes all your strings in UTF-8 by default. Even though, this is almost always the case, you can make sure of this by starting your scripts with # encoding: UTF-8.
If invalid, it is programmatically possible to detect most multi-byte encodings like UTF-8 (in Ruby, see: #valid_encoding?). However, it is NOT possible (or at least extremely hard) to programmatically detect invalidity of single-byte-encodings like ISO-8859-1. Thus the above code snippet does not work the other way around, i.e. detecting if a String is valid ISO-8859-1 encoding.
Even though UTF-8 has become increasingly popular as the default encoding in computer-systems, ISO-8859-1 and other Latin1 flavors are still very popular in the Western countries, especially in North America. Be aware that there a several single-byte encodings out there that are very similar, but slightly vary from ISO-8859-1. Examples: CP1252 (a.k.a. Windows-1252), ISO-8859-15
[ruby] [encoding] [utf8] [file-encoding] [character-encoding]
Please try this one:-
input_data = File.open("path/your_file.pdf", "rb") {|io| io.read}
Thanks