Ruby/LDAP non-ASCII character support - ruby

It seems like LDAP requires strings with non-ASCII characters to be Base64 encoded. The way to tell it that a string is to be parsed as a base64 encoded string is to add an extra colon to the attribute name such that "cn: name" becomes "cn:: name" (according to this site).
Now, my question is: How do I tell Ruby LDAP to do this? I could not find that the documentation mentions anything about it, but perhaps it is supported.
What about the other LDAP libraries, such as Net::LDAP? Do they support operations with non-ASCII characters?
Update:
The test suite for Ruby/LDAP (0.9.7, ruby v. 1.8.6) includes tests for adding entries with foreign characters in the LDAP. They set $KCODE="UTF8". However, this seems to have no effect in my setup.
non-ASCII characters are allowed for attributes as long as there is only ASCII-characters in the dn, so I currently use a workaround with an ASCII-only uid. However, this does not feel optimal.

I solved the problem by switching to Net::LDAP (which by the way feels much nicer to use). This required me to upgrade to ruby 1.8.7, though.

Related

Issues with using UTF-8 with PHPMailer

I'm using PHPMailer 5 to send plain text emails from forms. It looks like some users are pasting content from word into the textarea fields and the resulting email comes out with lots of non-readable characters (e.g. “).
I've tried adding $mail->CharSet = 'UTF-8'; and that seems to fix the tests I've done (e.g. bullet lists are now coming through properly).
$mail = new PHPMailer;
$mail->CharSet = 'UTF-8';
$mail->ContentType = 'text/plain';
$mail->IsHTML(false);
Are there any security issues or other issues that could come up from setting the character set to UTF-8?
You're doing it right. PHPMailer defaults (as does PHP's internal mail function) to the ISO-8859-1 character set because that can be used in the absence of the mbstring PHP extension which is not available by default - and if you don't have that extension, UTF-8 support won't work. Once you switch to using UTF-8, your entire toolchain must also use UTF-8 - your editors, your database, your database connection. You also need to be wary of functions like strlen and substr, which are not UTF-8-safe because they work in bytes, not chars (which may be more than 1 byte long). Whenever one of those things gets it wrong, you'll see the kind of corruption you have. It's a good exercise to stick in some difficult strings to test with (though see my answer about that) to make sure it comes through unscathed.
Unfortunately, MS Word is one of the best examples of how to do UTF-8 badly; it often riddles the text with unnecessary unusual characters, extra control chars etc, so I would advise doing some heavy filtering on your inputs - editors like CKEditor have built-in filters to help deal with Word's issues. That doesn't have anything to do with PHPMailer, it's a just a common problem with dealing with input that has been touched by Word.
The only thing you're doing wrong is using PHPMailer 5.x; current version is 6.x.

Using Ruby's fastercsv with character encodings

Using Ruby 1.8.7, I want to accept csv's into my system, even though this is an admin application, it seems I can get several different types of csvs. On my mac if I export from excel using "windows csv" option then fastercsv can read it out by default. On windows I seem to be getting utf-16 encoded csvs (which I havent figured out how to parse yet)
It seems like a pretty common thing to allow users to upload a csv that could be in utf8, utf16, ascii etc type formats, detect and parse them. Has anyone figured this out?
I started to look at UniversalDetector to help me detct, then use Iconv to convert, but this seems to be tricky and was hoping someone figured it out :)
According to FasterCSV's docs, the initialize method takes an :encoding option:
The encoding to use when parsing the file. Defaults to your $KDOCE setting. Valid values: n??? orN??? for none, e??? orE??? for EUC, s??? orS??? for SJIS, and u??? orU??? for UTF-8 (see Regexp.new()).
Because its list is limited, you might want to look into using iconv to do a pre-process of the contents, then pass them to CSV. You can use Ruby's interface to iconv ("Iconv") or the command-line version of it. Iconv is very powerful and flexible and capable of converting UTF-16 among other things.
Actually detecting the encoding of the document is more problematic, but the command-line version can help you there. If I remember right it can help identify the encoding. It can also convert between encodings, or, if you want, it can be told to convert to ASCII, converting to the closest matching characters, or ignoring them entirely.
Ruby 1.9.2 is much more capable than 1.8.7 when it comes to dealing with different character sets, so you might want to consider upgrading. Also, to become more familiar with the tools and issues of dealing with character-sets and multibyte characters you should read James Gray's blogs.

In Ruby, how to automatically convert non-supported characters in text-processing?

(Using Ruby 1.8)
I only have a brief understanding of encoding and such...but what I want to know is, in any given script handling any given text-file, is there some universal library or call I need to make to turn non-standard characters into their nearest printable equivalent. I realize there's no "all-in-one" fix, but this is for a English (U.S. gov't) text file, and so I'm wondering if there's something that mitigates what must be a relatively common issue in English text formatting.
For example, in a text file, I have an entry like this:
0-8­23
That hyphen is just literally a hyphen as I've typed it out. In the file though, it's something that looks like a hyphen (an n-dash?) but when copy and pasting it...for example, into this browser text box, it doesn't show up.
Printing it out via a Ruby script gets this:
08�23
How do I get my script to resolve it into a dash. Or something other than a gremlin?
It's very common to run into hyphen-like characters and dashes, especially in the output of word-processors. Converting them isn't too hard if you know what the byte is that represents the character, but gets to be a pain when you get a document with several different ones. It gets worse as you throw other accented characters into the mix.
Ruby 1.8 doesn't support multibyte and Unicode character sets as well as 1.9+, but you can work around that somewhat by using the Iconv library.
Iconv lets you convert between various character-sets, such as US-ASCII, ISO-8859-1 and WIN-1252. It's smarter than a regex, because it knows how to convert from accented characters, to similarly looking characters, or ignore them if nothing similar exists, allowing your transliteration to degrade gracefully.
I have some example code in an answer to a related question. Also read James Grey's article linked in the answer. It explains the problem and ways to fix it, ending up with recommending Iconv too.
You could whitelist with gsub:
string.gsub(/[^a-zA-Z0-9]/)
Without knowing more information, I can't build the perfect regex for you, but the general idea is to replace anything that's not what you're expecting (anything not a letter or number or expected symbols).

ruby string encoding

So, I'm trying to do some screen scraping off of a certain site using nokogiri, but the site owners failed to specify the proper encoding of the page in a <meta> tag. The upshot of this is that I'm trying to deal with strings that think they're utf-8, but really aren't.
(If you care, here are the files I was using to test this:
main file: http://dpaste.de/nif5/
ann.html: http://dpaste.de/YsLM/
ann2.html: http://dpaste.de/Lofi/
ann3.html: http://dpaste.de/R21j/
a-p.html: http://dpaste.de/O9dy/
output: http://dpaste.de/WdXc/
)
After doing a lot of searching around (this SO question was particularly useful), I found that calling encode('iso-8859-1', 'utf-8') on that test string "works", in that I get a proper © symbol. The issue now is that there are other characters in some other strings I want that really do not work at being converted to latin encoding (Shōta, for instance, turns into Sh�\x8Dta).
Now, I'm probably going to bother the appropriate webmasters and try and get them to fix their damn encodings, but in the meantime, I'd like to be able to use the bytes that I've got. I'm fairly certain that there is a way, but I just can't for the life of me figure out what it is.
Those pages appear to be correctly encoded as UTF-8. That's how my browser sees them, and when I viewsource them and tell the editor to decode them as UTF-8, they look fine. The only problem I see is that some copyright symbols seem to have been corrupted before (or as) they were added to the content. The o-macron and other non-ASCII letters come through just fine.
I don't know if you're aware of this, but the proper way to notify clients of a page's encoding is through a header. Pages may include that information in <meta> tags, but that's neither required nor expected; browsers typically ignore such tags if the header is present.
Since your pages are XHTML, they could also embed the encoding information in an XML processing instruction, but again, they're not required to. But it als means you could have Nokogiri treat them as XML instead of HTML, in which case I would expect it to use UTF-8 by default. But I'm not familiar with Nokogiri, so I can't be sure. And anyway, the header is still the final authority.
So, the issue is that ANN only specifies encoding via headers, and Nokogiri doesn't receive the headers from the open() function. So, Nokogiri guesses that the page is latin-encoded, and produces strings that we really can't reverse to get back the original characters from.
You can specify the encoding to Nokogiri as the 3rd parameter to Nokogiri::HTML(), which solves the issue I was initially trying to solve. So, I'll accept this answer, even though the more specific question I asked (how to get those non-latin characters out of a latin string) is unanswerable.

Enhancing an ASCII protcol with multilingual fields

I am enhancing a piece of software that implements a simple ASCII based protocol.
The protocol is simple... here is an example of what the messages look a little bit like (not the same though, I can't show you the real protocol):
AUTH 1 1 200<CR><LF>
To which we get a response looking similar to
230 DEVICE 1 STATE AUTH 200 OUTPUT 1 NAME "Photo Black"<CR><LF>
The name "Photo Black" comes from a database sqlite database. I need to enhance it to support foreign languages. So I've been thinking that the field "Photo Black" needs to be "optionally" encoded as a UTF-8 string between the quotes. I'm wondering if there is a standard for this so that the client application can interpret the string in the quotes and straight away recognize it as either UTF-8 or plain ASCII. I'm not willing to rewrite the protocol, that would be too much work. Just slip in some kind of encoding for clients to recognize some Spanish or Swedish names.
I don't want the field to be always interpreted as UTF-8 either, long story there. You know how in C++ I can type 0xFF and the compiler knows that this is a hex string... is there an equivalent for UTF-8? Sorry I may be jumping the gun but I'm not that familiar with UTF-8 encoding and internationalization in general.
Do you have control over both the server and the client? If not, you can't change the protocol so you won't be able to do it. When you say you're "not wiling to rewrite the protocol" - you're going to have to do so at least to some extent. Whatever you do, you will be changing the protocol.
I'm not sure why you wouldn't want to always interpret the data as UTF-8 either - if it's currently only ASCII, then it would be completely backward compatible to always interpret it as UTF-8, as all ASCII is encoded the same way in UTF-8. Perhaps if you could give more information, we could provide more help.
You could introduce a prefix for UTF-8-encoded strings, e.g. U:
230 DEVICE 1 STATE AUTH 200 OUTPUT 1 NAME U"Photo UTF-8 stuff here Black"<CR><LF>
would that help?
Do you actually have an 8-bit data path? If something is going to mangle the top bit of every byte, then you'll need to consider options like Punycode instead of UTF-8.
Read up on the concept of Ascii Compatible Encoding, or ACE. iDNS is an example. So is/was UTF-7.
Here's the master speaking.
You really can't code-switch in and out of UTF-8. For a nightmare, look up ISO-2022, which attempted to support that sort of thing. Also keep in mind that UTF-8 includes ASCII, but not Latin-1.
Why don't you want the field to be "always interpreted as UTF-8"? You don't say.
If you do have the client interpret the protocol as UTF-8 encoded text, all of the existing output will still work correctly, since UTF-8 is a proper superset of ASCII.

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