We have a Java UUID being written to a ByteArrayOutputStream. Then bytearray of that ByteArrayOutputStream is base64 encoded and sent in a JSON. The encoding process is as follows.
public String uuidToString(UUID uuidObj) {
final ByteArrayOutputStream baos = new ByteArrayOutputStream();
final DataOutputStream dos = new DataOutputStream(baos);
dos.writeLong(uuidObj.getMostSignificantBits());
dos.writeLong(uuidObj.getLeastSignificantBits());
dos.flush();
return Base64.encodeBase64URLSafeString(baos.toByteArray());
}
I am trying to figure out how to decode this String in the javascript side. Ofcourse the base64 part is easy. Using atob I get a String and then using Crypto.js I can get a byte array out of that base64 decoded String. Then I tried to use the conversion techniques mentioned in the following link to convert but its always returning garbage.
Converting byte array to string in javascript
Using the String as is directly in JSON is not an option for a couple of reasons. Firstly we want to keep this String opaque, but we also want to keep the size of the final encoded string that is sent over the wire to be small.
I know another option is protocol buffers, but the lack of a supported js implementation and the extra build time leg work seem to be barriers on that front.
So do I have any other options ? And any suggestions on why my javascript decoding isn't working.
Related
I need to send audio data to an API which requires a base64 string as input.
Therefore I'm looking for a way to convert an Int16Array to a base64 string. Is there a simple procedure to do that? All methods that I've found so far applied to uint8 data...
I want to send a BLOB to an APEX RESTful service. The payload has to be a JSON (not form-data, I've had a lor of problems with that in the server side).
The BLOB is an image that I need to upload to the DB, my problem is that I don't know how to send the data in the payload. Should it be a string that represents the array of bytes? Should it be the array itself? (I managed to extract a binary string with the readASBinaryString method of javascipt's FileReader).
Thanks for any help.
Your BLOB data could be encoded to Base64 and then transported in JSON document as a string. You can use window.btoa() to convert binary data to Base64 string.
For example:
{
"data": "SGVsbG8gd29ybGQ="
}
I have been breaking my head for the last couple of days trying to save the screenshot from a ThreeJS on the server using .NET Web API.
I have gone through all the possible questions on this specific topic and related ones on StackOverflow and tried the suggestions as well.
The issue details are specified below:
I am successfully able to get the base64 encoded string from renderer.domElement.toDataUrl() which contains a valid threejs image.
When I pass this string as is to my .NET WebAPI, the Convert.FromBase64String() method fails saying invalid length of the Base64 string or invalid padding characters. I ensured to extract out the "data:image/png;base64," part before passing.
I tried a number of things to resolve this issue like adding padding characters to ensure the length is mod 4, using regular expression to extract out the right data. I was able to get through the Convert.FromBase64String() and saved the resulting byte array as a png on my server. It resulted in a blank image.
I also discovered that when I used the chrome extension Advanced Rest Client to hit my WebAPI and used the Encode Payload feature before posting the string, I was able to get the image saved on my server successfully and got back the desired image as well.
Seeing this, I used the encodeURIComponent() function in Javascript to pass my base64 string to the WebAPI from my web app, but failed, getting back the same behavior as my earlier attempts.
One important observation was that the whitespaces were getting eliminated in case of Encode Payload but not in case of encodeURIComponent.
I compared the strings between encodeURIComponent() and the Encode Payload from Advanced Rest Client. Although, on a high level, they do the same thing by replacing the special characters with their escape sequences, there is still a significant difference between them.
Request help on this issue.
I would like to know if there is any other way of getting the threejs base64 string passed to .NET successfully.
What might be the difference between the encoding of encodeURIComponent and Advanced Rest Client Encode Payload feature?
Thanks in advance!
I am sending the return url as a query string parameter like this http://localhost:50316/TripNestFinal/Login.aspx?ReturnUrl=~/Account/AccountSettings.aspx
But i want ~/Account/AccountSettings.aspx to be encoded in such a way so that i can
encode/decode in jQuery/javascript
encode/decode in VB.NET
encode in VB.NET and decode in javascript/jQuery and vice versa
This doesn't have to be bulletproof as i am not dealing with security here. All i want to do is to change this ~/Account/AccountSettings.aspx to something that does not show the path directly.
I thought of using Base64 encoding but when i Base64 Encode , it includes a '/' character which breaks my jQuery logic. Is there any way i can avoid the '/' character when i Base64 encode?
You will need to URL encode the Base64 encoded string, that will work - although you'll need to check the generated query string length to make sure it doesn't hit the .NET maximum.
But I have to ask why you'd want to encode it in this way?
I created a JSONP function on the server and returns a UTF-8 encoded json object like this
applyLocalization({"Name":"%E5%90%8D%E5%89%8D","Age":"%E5%B9%B4%E9%BD%A2"});
on my javascript on the client side, i want to convert the garbled part to their original state like
{"Name":"名前", "Age":"年齢"}
I tried $.parseJSON() but it doesnt work
You can use decodeURIComponent to decode urlencoded strings like yours
decodeURIComponent('%E5%90%8D%E5%89%8D');
//result: '名前'
You could use the decodeURIComponent function. But you shouldn't be URL encoding your javascript strings. You should send them as UTF-8 strings as-is. Javascript is capable of understanding them.