I'm creating an app that's subscribe users to FCM topics. This topics in many cases have a special chars in yours names. Thereby I'm converting this topics names into base64 string like this:
byte[] data = myText.getText().toString().getBytes(StandardCharsets.UTF_8);
String base64 = Base64.encodeToString(data, Base64.DEFAULT);
String converted = base64.replace("\n","");
In many cases the above code works perfectly. But there are some cases where the base64 function generates strings like this: "UHJvcHJpw6E=". The equal symbol is not allowed in FCM topics name. How to solve this issue?
Base on the documentation the NO_PADDING flag should fix the problem.
int NO_PADDING Encoder flag bit to omit the padding '=' characters at the end of the output (if any).
String base64 = Base64.encodeToString(data, Base64.NO_PADDING);
For a better understanding check Base64 documantation.
Related
I'm working on a function to decode a string (from a header) that is encoded in both Base64 and RFC2047 in Java.
Given this header:
SGVhZGVyOiBoZWFkZXJ2YWx1ZQ0KQmFkOiBOYW1lOiBiYWRuYW1ldmFsdWUNClVuaWNvZGU6ID0/VVRGLTg/Qj81YmV4NXF5eTU2dUw2SUNNNTZ1TDVMcTY3N3lNNWJleDVxeXk2WUdVNklDTTZZR1U/PSA9P1VURi04P0I/NUxxNjc3eU01YmV4NW9tQTVMaU41cXl5Nzd5TTVZdS81cGE5NXBhODVMcTY0NENDPz0NCg0K
My expected output is:
Header: headervalue Bad: Name: badnamevalue Unicode:
己欲立而立人，己欲達而達人，己所不欲，勿施於人。
The only relevant function that I have found and tried was Base64.decodeBase64(headers), which produces this when printed out:
Header: headervalue Bad: Name: badnamevalue Unicode:
=?UTF-8?B?5bex5qyy56uL6ICM56uL5Lq677yM5bex5qyy6YGU6ICM6YGU?= =?UTF-8?B?5Lq677yM5bex5omA5LiN5qyy77yM5Yu/5pa95pa85Lq644CC?=
To solve this, I've been trying MimeUtility.decode() by converting the byte array returned from Base64.decodeBase64(headers) to InputStream, but the result was identical as above.
InputStream headerStream = new ByteArrayInputStream(Base64.decodeBase64(headers));
InputStream result = MimeUtility.decode(headerStream, "quoted-printable");
Have been searching around the internet but have yet found a solution, wondering if anyone knows ways to decode MIME headers from resulted byte arrays?
Any help is appreciated! It's also my first stack overflow post, apologies if I'm missing anything but please let me know if there's more information that I can provide!
The base64 you have there actually is what you pasted. Including the bizarre =?UTF-8?B? weirdness.
The stuff that follows is again base64.
There's base64-encoded data inside your base-64 encoded data. As Xzibit would say: I put some Base64 in your base64 so you can base64 while you base64. Why do I feel old all of a sudden?
In other words, the base64 input you get is a crazy, extremely inefficient format invented by a crazy person.
My advice is that you tell them to come up with something less insane.
Failing that:
Search the resulting string for the regex pattern and then again apply base64 decode to the stuff in the middle.
Also, you're using some third party base64 decoder, probably apache. Apache libraries tend to suck. Base64 is baked into java, there is no reason to use worse libraries here. I've fixed that; the Base64 in this snippet is java.util.Base64. Its API is slightly different.
String sourceB64 = "SGV..."; // that input base64 you have.
byte[] sourceBytes = Base64.decodeBase64(sourceB64);
String source = new String(sourceBytes, StandardCharsets.UTF_8);
Pattern p = Pattern.compile("=\\?UTF-8\\?B\\?(.*?)\\?=");
Matcher m = p.matcher(source);
StringBuilder out = new StringBuilder();
int curPos = 0;
while (m.find()) {
out.append(source.substring(curPos, m.start()));
curPos = m.end();
String content = new String(Base64.getDecoder().decode(m.group(1)), StandardCharsets.UTF_8);
out.append(content);
}
out.append(source.substring(curPos));
System.out.println(out.toString());
If I run that, I get:
Header: headervalue
Bad: Name: badnamevalue
Unicode: 己欲立而立人，己欲達而達 人，己所不欲，勿施於人。
Which looks exactly like what you want.
Explanation of that code:
It first base64-decodes the input, and turns that into a string. (Your idea of using InputStream is a red herring. That doesn't help at all here. You just want to turn bytes into a string, you do it as per line 3 of that snippet. Pass the byte array and the encoding those bytes are in, that's all you need to do).
It then goes on the hunt for =?UTF-8?B?--base64here--?= inside your base64. The base64-in-the-base64.
It then decoder that base64, turns it into a string in the same fashion, and replaces it.
It just adds everything besides those =?UTF-8?B?...?= segments verbatim.
I am working with the GCS API, attempting to create a survey with image data.
I am using the NuGet package Google.Apis.ConsumerSurveys.v2 version 1.14.0.564 on the .Net platform. I can create surveys that do not contain image data without problem. However, when I try to create a survey with image data I receive an error from the API.
I have on hand base64 encoded png format image data. My images display properly in an IMG tag on a web page when the src attribute is set to
'data:image/png;base64,<image base64 string>'
I want to send this image data to the API to populate the survey image. My understanding is that I need to set the Data property of the Google.Apis.ConsumerSurveys.v2.Data.SurveyQuestionImage object to a string containing the image data. I have not been successful.
I first decode my base64 string to a byte array:
byte[] bytes = Convert.FromBase64String(<image base64 string>);
I have tried setting the Data property in the SurveyQuestionImage object as:
image.Data = Encoding.Unicode.GetString(bytes);
This results in this error from the API:
Google.Apis.Requests.RequestError Invalid value for ByteString: <the Data string>
I have also tried converting the byte array to a hexadecimal encoded string as:
StringBuilder sb = new StringBuilder(bytes.Length);
foreach (Byte b in bytes)
{
sb.Append(b.ToString("X2"));
}
image.Data = sb.ToString();
This results in the more hopeful error:
Google.Apis.Requests.RequestError Invalid Value supplied to API: image_data was bad. Request Id: 579665c300ff05e6c316a09e600001737e3430322d747269616c320001707573682d30372d32322d72313000010112 [400] Errors [ Message[Invalid Value supplied to API: image_data was bad. Request Id: 579665c300ff05e6c316a09e600001737e3430322d747269616c320001707573682d30372d32322d72313000010112] Location[ - ] Reason[INVALID_VALUE] Domain[global] ]
Does anyone know the correct format for the Data property of the Google.Apis.ConsumerSurveys.v2.Data.SurveyQuestionImage object?
The data needs to be base64 encoded and also "urlsafe" or "websafe" depending on what language you are using. (python and java, respectively)
In other words, you'll need to first base64 encode then:
Web safe encoding uses '-' instead of '+', '_' instead of '/'
Hope this helps!
For c# users, check out this technique for making websafe b64:
How to achieve Base64 URL safe encoding in C#?
For .net users, look at the comments in this question:
Converting string to web-safe Base64 format
And also this link for more info about .net specific options for encoding:
http://www.codeproject.com/Tips/76650/Base-base-url-base-url-and-z-base-encoding
And to specifically answer the original poster, try this for converting your byte array to a string.
public static string ToBase64ForUrlString(byte[] input)
{
StringBuilder result = new StringBuilder(Convert.ToBase64String(input).TrimEnd('='));
result.Replace('+', '-');
result.Replace('/', '_');
return result.ToString();
}
I'm writing a REST client from a C# usage example. Now i need to convert a string in the proper format but can't find the equivalent method on Java.
original:
string Credentials = Convert.ToBase64String(ASCIIEncoding.ASCII.GetBytes(string);
At this point I've done this:
String Credentials = new String(DatatypeConverter.parseBase64Binary(String));
but i still need the ASCII conversion and I'm not sure that the things I've fount will work fine, like: Convert character to ASCII numeric value in java
any clues?
Thank you.
If you're using java 8 you should take a look at its new Base64 class. It will provide you with a Base64.Encoder whose encodeToString(byte[] src) method accepts a byte array and return a base64 encoded String.
String base64 = Base64.getEncoder().encodeToString("I'm a String".getBytes());
System.out.println(base64); // prints SSdtIGEgU3RyaW5n
I have a string that is base64 encoded. It looks like this:
eyJibGExIjoiYmxhMSIsImJsYTIiOiJibGEyIn0=
Any online tool can decode this to the proper string which is {"bla1":"bla1","bla2":"bla2"}. However, my Java implementation fails:
import java.util.Base64;
System.out.println("payload = " + payload);
String json = new String(Base64.getDecoder().decode(payload));
I'm getting the following error:
payload = eyJibGExIjoiYmxhMSIsImJsYTIiOiJibGEyIn0=
java.lang.IllegalArgumentException: Input byte array has incorrect ending byte at 40
What is wrong with my code?
Okay, I found out. The original String is encoded on an Android device using android.util.Base64 by Base64.encodeToString(json.getBytes("UTF-8"), Base64.DEFAULT);. It uses android.util.Base64.DEFAULT encoding scheme.
Then on the server side when using java.util.Base64 this has to be decoded with Base64.getMimeDecoder().decode(payload) not with Base64.getDecoder().decode(payload)
I was trying to use the strings from the args. I found that if I use arg[0].trim() that it made it work. eg
Base64.getDecoder().decode(arg[0].trim());
I guess there's some sort of whitespace that gets it messed up.
Maybe too late, but I also had this problem.
By default, the Android Base64 util adds a newline character to the end of the encoded string.
The Base64.NO_WRAP flag tells the util to create the encoded string without the newline character.
Your android app should encode src something like this:
String encode = Base64.encodeToString(src.getBytes(), Base64.NO_WRAP);
I am trying to make a call to a ws-security secured webservice from a server which unfortunately does not support this natively. The approach I have taken is to implement a .jsp which acts as reverse proxy to the actual end point URL, in the process adding the element with ws-security elements.
This seems to be working quite well and I am confident I've constructed the XML correctly with the correct namespaces etc. I've verified this by comparing the XML with XML produced by SOAP-UI.
The problem is in implementing the password digest generator. I don't get the same result as what SOAP-UI does using the same inputs for NOnce, xsd:dateTime and password, and the following code.
StringBuffer passwordDigestStr_ = new StringBuffer();
// First append the NOnce from the SOAP header
passwordDigestStr_.append(Base64.decode("PzlbwtWRpmFWjG0JRIRn7A=="));
// Then append the xsd:dateTime in UTC timezone
passwordDigestStr_.append("2012-06-09T18:41:03.640Z");
// Finally append the password/secret
passwordDigestStr_.append("password");
System.out.println("Generated password digest: " + new String(com.bea.xbean.util.Base64.encode(org.apache.commons.codec.digest.DigestUtils.sha(passwordDigestStr_.toString())), "UTF-8"));
I think the problem is with implementing the hashing of the first two elements as explained by http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0.pdf
Note that the nonce is hashed using the octet sequence of its decoded value while the timestamp is hashed using the octet sequence of its UTF8 encoding as specified in the contents of the element.
If anyone could help me solve this problem that would be great because it's beginning to drive me crazy! It would be ideal if you could provide source code.
I'll take a crack at it without SOAP-UI. The input to the hash function is supposed to be bytes, not a string. DigestUtils.sha() will allow you to use a string, but that string must be properly encoded. When you wrote the nonce, you were calling StringBuffer.append(Object) which ends up calling byte[].toString(). That gives you something like [B#3e25a5, definitely not what you want. By using bytes everywhere, you should avoid this problem. Note that the example below uses org.apache.commons.codec.binary.Base64, not the Base64 class you were using. It doesn't matter, that's just the one I had handy.
ByteBuffer buf = ByteBuffer.allocate(1000);
buf.put(Base64.decodeBase64("PzlbwtWRpmFWjG0JRIRn7A=="));
buf.put("2012-06-09T18:41:03.640Z".getBytes("UTF-8"));
buf.put("password".getBytes("UTF-8"));
byte[] toHash = new byte[buf.position()];
buf.rewind();
buf.get(toHash);
byte[] hash = DigestUtils.sha(toHash);
System.out.println("Generated password digest: " + Base64.encodeBase64String(hash));
Apologies for the delay in replying, especially considering your initial quick response. I have now been able to get this to work using the essence of your approach to avoid any character encoding issues. However, java.nio.ByteBuffer caused me issues so I modified the code to use basic byte[]s which I combined using System.arrayCopy(). The problem I faced with java.nio.ByteBuffer was that despite 'buf.position()' returning an appropriate number of bytes, all the bytes injected into byte[] toHash through buf.get(toHash) were 0s!
Thanks very much for your assistance.