I am trying to save a file, with the below code, in different encoding, for example ANSI.
How can I do this, on Windows?
file=File.new("c:/ruby/hps.txt","w")
file.puts 'there is some text'
file.close
There's an example in the Encoding documentation about how to do this. open, File.new, and IO.new all take the same mode and encoding arguments.
Using File.open with a block is safer and more succinct than managing the filehandle yourself.
File.open("c:/ruby/hps.txt", "w:ISO-8859-1") do |f|
f.write("some text")
end
This example writes the string as ISO 8859-1 aka Windows-1252 aka Latin-1.
"ANSI" encoding is ambiguous. Check Encoding.list for what's available.
Related
How can I load a YAML file regardlessly of its encoding?
My YAML file can be encoded in UTF-8 or ANSI (that's what Notepad++ calls it - I guess it's Windows-1252):
:key1:
:key2: "ä"
utf8.yml is encoded in UTF-8, ansi.yml is encoded in ANSI. I load the files as follows:
# encoding: utf-8
Encoding.default_internal = "utf-8"
utf8_load = YAML::load(File.open('utf8.yml'))
utf8_load_file = YAML::load_file('utf8.yml')
ansi_load = YAML::load(File.open('ansi.yml'))
ansi_load_file = YAML::load_file('ansi.yml')
It seems like Ruby doesn't recognize the encoding correctly:
utf8_load [:key1][:key2].encoding #=> "UTF-8"
utf8_load_file [:key1][:key2].encoding #=> "UTF-8"
ansi_load [:key1][:key2].encoding #=> "UTF-8"
ansi_load_file [:key1][:key2].encoding #=> "UTF-8"
because the bytes aren't the same:
utf8_load [:key1][:key2].bytes #=> [195, 164]
utf8_load_file [:key1][:key2].bytes #=> [195, 164]
ansi_load [:key1][:key2].bytes #=> [239, 191, 189]
ansi_load_file [:key1][:key2].bytes #=> [239, 191, 189]
If I miss Encoding.default_internal = "utf-8", the bytes are also different:
utf8_load [:key1][:key2].bytes #=> [195, 131, 194, 164]
utf8_load_file [:key1][:key2].bytes #=> [195, 164]
ansi_load [:key1][:key2].bytes #=> [195, 164]
ansi_load_file [:key1][:key2].bytes #=> [239, 191, 189]
What happens actually when I don't set the default_internal to utf-8?
Which encodings do the strings in both examples have?
How can I load a file even if I don't know its encoding?
I believe officially YAML only supports UTF-8 (and maybe UTF-16). There have historically been all sorts of encoding confusions in YAML libraries. I think you are going to run into trouble trying to have YAML in something other than a Unicode encoding.
What happens actually when I don't set the default_internal to utf-8?
Encoding.default_internal controls the encoding your input will be converted to when it is read in, at least by some operations that respect Encoding.default_internal, not everything does. Rails seems to set it to UTF-8. So if you don't set the Encoding.default_internal to UTF-8, it might be UTF-8 already anyway.
If Encoding.default_internal is nil, then those operations that respect it, and try to convert any input to Encoding.default_internal upon reading it in won't do that, they'll leave any input in the encoding it was believed to originate in, not try to convert it.
If you set it to something else, like say "WINDOWS-1252" Ruby would automatically convert your stuff to WINDOWS-1252 when it read it in with File.open, which would possibly confuse YAML::load when you pass the string that's now encoded and tagged as WINDOWS-1252 to it. Generally there's no good reason to do this, so leave Encoding.default_internal alone.
Note: The Ruby docs say:
"You should not set ::default_internal in Ruby code as strings created before changing the value may have a different encoding from strings created after the change. Instead you should use ruby -E to invoke Ruby with the correct default_internal."
See also: http://ruby-doc.org/core-1.9.3/Encoding.html#method-c-default_internal
Which encodings do the strings in both examples have?
I don't really know. One would have to have to look at the bytes and try to figure out if they are legal bytes for various plausible encodings, and beyond being legal, if they mean something likely to be intended.
For example take: "ÉGÉìÉRÅ[ÉfÉBÉìÉOÇÕìÔǵÇ≠ǻǢ". That's a perfectly legal UTF-8 string, but as humans we know it's probably not intended, and is probably garbage, quite likely from the result of an encoding misinterpretation. But a computer has no way to know that, it's perfectly legal UTF-8, and, hey, maybe someone actually did mean to write "ÉGÉìÉRÅ[ÉfÉBÉìÉOÇÕìÔǵÇ≠ǻǢ", after all, I just did, when writing this post!
So you can try to interpret the bytes according to various encodings and see if any of them make sense.
You're really just guessing at this point. Which means...
How can I load a file even if I don't know it's encoding?
Generally, you can not. You need to know and keep track of encodings. There's no real way to know what the bytes mean without knowing their encoding.
If you have some legacy data for which you've lost this, you've got to try to figure it out. Manually, or with some code that tries to guess likely encodings based on heuristics. Here's one Ruby gem Charlock Holmes that tries to guess, using the ICU library heuristics (this particular gem only works on MRI).
What Ruby says in response to string.encoding is just the encoding the string is tagged with. The string can be tagged with the wrong encoding, the bytes in the string don't actually mean what is intended in the encoding it's tagged with... in which case you'll get garbage.
Ruby will do the right things with your string instead of creating garbage only if the string's encoding tag is correct. The string's encoding tag is determined by Encoding.default_external for most input operations by default (Encoding.default_external usually starts out as UTF-8, or ASCII-8BIT which really means the null encoding, binary data, not tagged with an encoding), or by passing an argument to File.open: File.open("something", "r:UTF-8" or, means the same thing, File.open("something", "r", :encoding => "UTF-8"). The actual bytes are determined by whatever is in the file. It's up to you to tell Ruby the correct encoding to interpret those bytes as text meaning what they were intended to mean.
There were a couple posts recently to reddit /r/ruby that try to explain how to troubleshoot and workaround encoding issues that you may find helpful:
http://www.justinweiss.com/articles/how-to-get-from-theyre-to-theyre/
http://www.justinweiss.com/articles/3-steps-to-fix-encoding-problems-in-ruby/
Also, this is my favorite article on understanding encoding generally: http://kunststube.net/encoding/
For YAML files in particular, if I were you, I'd just make sure they are all in UTF-8. Life will be much easier and you won't have to worry about it. If you have some legacy ones that have become corrupted, it's going to be a pain to fix them, but that's what you've got to do, unless you can just rewrite them from scratch. Try to fix them to be in valid and correct UTF-8, and from here on out keep all your YAML in UTF-8.
The YAML specification says in "5.1. Character Set":
To ensure readability, YAML streams use only the printable subset of the Unicode character set. The allowed character range explicitly excludes the C0 control block #x0-#x1F (except for TAB #x9, LF #xA, and CR #xD which are allowed), DEL #x7F, the C1 control block #x80-#x9F (except for NEL #x85 which is allowed), the surrogate block #xD800-#xDFFF, #xFFFE, and #xFFFF.
This means that Windows-1252 or ISO-8859-1 encoding are acceptable as long as the characters being output are within the defined range. Windows users tend to use the "the C1 control block #x80-#x9F" range for diacritical and accented characters, so if those are present in a YAML file the file is not going to meet the spec and the YAML generator didn't do its job correctly. And that explains why "ä" isn't acceptable.
On output, a YAML processor must only produce acceptable characters. Any excluded characters must be presented using escape sequences. In addition, any allowed characters known to be non-printable should also be escaped. This isn’t mandatory since a full implementation would require extensive character property tables.
These days, by default, Ruby uses UTF-8, however YAML isn't limited to that. The spec goes on to say in "5.2. Character Encodings":
On input, a YAML processor must support the UTF-8 and UTF-16 character encodings. For JSON compatibility, the UTF-32 encodings must also be supported.
If a character stream begins with a byte order mark, the character encoding will be taken to be as as indicated by the byte order mark. Otherwise, the stream must begin with an ASCII character. This allows the encoding to be deduced by the pattern of null (#x00) characters.
So, UTF-8, 16 and 32 are supported, but Ruby will assume UTF-8. If the BOM is present you'll see it when you view the file in an editor. I haven't tried loading a UTF-16 or 32 file to see what Ruby's YAML does, so that's left as an experiment.
I'm trying to get a list of files from url like this:
require 'uri'
require 'open-uri'
url = 'http://www.wmprof.com/media/niti/download'
html = open(url).read
puts URI.extract(html).select{ |link| link[/(PL)/]}
This code returns ArgumentError: invalid byte sequence in UTF-8 in line with URI.extract (even though html.encoding returns utf-8)
I've found some solutions to encoding problems, but when I'm changing the code to
html.encode('UTF-8', invalid: :replace, undef: :replace, replace: '?')
URI.extract returns empty string, even when I'm not calling the select method on it. Any suggestions?
The character encoding of the website might be ISO-8859-1 or a related one. We can't tell for sure since there are only two occurrences of the same non-US-ASCII-character and it doesn't really matter anyway.
html.each_char.reject(&:ascii_only?) # => ["\xDC", "\xDC"]
Finding the actual encoding is done by guessing. The age of HTML 3.2 or the used language/s might be a clue. And in this case especially the content of the PDF file is helpful (it contains SPRÜH-EX and the file has the name TI_DE_SPR%dcH_EX.pdf). Then we only need to find the encoding for which "\xDC" and "Ü" are equal. Either by knowing it or writing some Ruby:
Encoding.list.select { |e| "Ü" == "\xDC".encode!(Encoding::UTF_8, e) rescue next }.map(&:name)
Of course, letting a program do the guessing is an option too. There is the libguess library. The web browser can do it too. However you you need to download the file though unless the server might tell the browser it's UTF-8 even if it isn't (like in this case). Any decent text editor will also try to detect the file encoding: e.g. ST3 thinks it's Windows 1252 which is a superset of ISO-8859-1 (like UTF-8 is of US-ASCII).
Possible solutions are manually setting the string encoding to ISO-8859-1:
html.force_encoding(Encoding::ISO_8859_1)
Or (preferably) transcoding the string from ISO-8859-1 to UTF-8:
html.encode!(Encoding::UTF_8, Encoding::ISO_8859_1)
To answer the other question: URI.extract isn't the method you're looking for. Apparently it's obsolete and more importantly, it doesn't extract relative URI.
A simple alternative is using a regular expression with String#scan. It works with this site but it might not with other ones. You have to use a HTML parser for the best reliability (there might be also a gem). Here's an example that should do what you want:
html.scan(/href="(.*?PL.*?)"/).flatten # => ["SI_PL_ACTIV_bicompact.pdf", ...]
I have a yaml file with a pound-sterling sign on it -
amount: "£50"
when I access the symbol it return the following:
"£50"
I am using hashie:mash to load and access my yaml... ideas are welcome, haven't found anything on the webs that give a straight forward solution (or at least one that works for me)
The external encoding is your issue; Ruby is assuming that any data read from external files is CP-850, rather than UTF-8.
You can solve this a few ways:
Set Encoding.default_external ='utf-8'. This will tell Ruby to read files as UTF-8 by default.
Explicitly read your file as UTF-8, via open('file.yml', 'r:utf-8')
Convert your string to UTF-8 before you pass it to your YAML parser:
You can do this via String#force_encoding, which tells Ruby to reinterpret the raw bytes with a different encoding:
text = open("file.yml").read
text.force_encoding("utf-8")
YAML.load text
I want to save ® into a txt file with UTF-16 Little Endian, I tested in some ways
1.The encoding below is UTF-8
$RegisterMark=[174].pack('U*')
file = File.new("C:/Output.txt","w")
file.puts $RegisterMark
file.close
2.The encoding below is UTF-16 Big Endian
require 'iconv'
$RegisterMark=[174].pack('U*')
$utf16RegisterMark =Iconv.conv('UTF-16', 'UTF-8', $RegisterMark )
file = File.new("C:/Output.txt","w")
file.puts $utf16RegisterMark
file.close
The mentod Iconv.conv doesn't suport UTF-16 LE type.
How can I save output.txt with UTF16 LE?
The easiest way is to just open the file as UTF-16LE in the first place:
register_mark = "\00ua3" # or even just: register_mark = ®
File.open('C:/Output.txt', 'wt', encoding: 'UTF-16LE') do |f|
f.puts register_mark
end
The important bit here is to explicitly specify the encoding of the file, using the :encoding key in the options Hash of the File.new method (or in this case, File.open). That way, strings written to the file will be converted automatically, no matter what encoding they are in.
I also took the liberty of changing your code to a more idiomatic Ruby style:
The Ruby community uses snake_case, not CamelCase for variable and method names.
Global variables should be avoided, especially since in your example, they are totally superfluous anyway.
There's really no need to use Array#pack here, just write down what you want.
Whenever possible, use the block form of File.open, which will take care of closing the file for you, even in the case of an error or exception.
When dealing with text files, you should always pass the t modifier. It doesn't make any difference on most operating systems (which is why, unfortunately, most Rubyists forget to pass it), but it is crucial on Windows, which is what you appear to be using.
Somewhat hacky, but this worked for me. Specifically, I was trying to get ruby to output UTF-16LE w/ BOM
## Adds BOM, albeit in a somewhat hacky way.
new_html_file = File.open(foo.txt, "w:UTF-8")
new_html_file << "\xFF\xFE".force_encoding('utf-16le') + some_text.force_encoding('utf-8').encode('utf-16le')
I have a ISO-8859-1 encoded csv-file that I try to open and parse with ruby:
require 'csv'
filename = File.expand_path('~/myfile.csv')
file = File.open(filename, "r:ISO-8859-1")
CSV.parse(file.read, col_sep: "\t") do |row|
puts row
end
If I leave out the encoding from the call to File.open, I get an error
ArgumentError: invalid byte sequence in UTF-8
My problem is that the call to puts row displays strange characters instead of the norwegian characters æ,ø,å:
BOKF�RINGSDATO
I get the same if I open the file in textmate, forcing it to use UTF-8 encoding.
By assigning the file content to a string, I can check the encoding used for the string. As expected, it shows ISO-8859-1.
So when I puts each row, why does it output the string as UTF-8?
Is it something to do with the csv-library?
I use ruby 1.9.2.
Found myself an answer by trying different things from the documentation:
require 'csv'
filename = File.expand_path('~/myfile.csv')
File.open(filename, "r:ISO-8859-1") do |file|
CSV.parse(file.read.encode("UTF-8"), col_sep: "\t") do |row|
# ↳ returns a copy transcoded to UTF-8.
puts row
end
end
As you can see, all I have done, is to encode the string to an UTF-8 string before the CSV-parser gets it.
Edit:
Trying this solution on macruby-head, I get the following error message from encode( ):
Encoding::InvalidByteSequenceError: "\xD8" on UTF-8
Even though I specify encoding when opening the file, macruby use UTF-8.
This seems to be an known macruby limitation: Encoding is always UTF-8
Maybe you could use Iconv to convert the file contents to UTF-8 before parsing?
ISO-8859-1 and Win-1252 are reaallly close in their character sets. Could some app have processed the file and converted it? Or could it have been received from a machine that was defaulting to Win-1252, which is Window's standard setting?
Software that senses the code-set can get the encoding wrong if there are no characters in the 0x80 to 0x9F byte-range so you might try setting file = File.open(filename, "r:ISO-8859-1") to file = File.open(filename, "r:Windows-1252"). (I think "Windows-1252" is the right encoding name.)
I used to write spiders, and HTML is notorious for being mis-labeled or for having encoded binary characters from one character set embedded in another. I used some bad language many times over these problems several years ago, before most languages had implemented UTF-8 and Unicode so I understand the frustration.
ISO/IEC_8859-1,
Windows-1252