You can not select more than 25 topics
			Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
		
		
		
		
		
			
		
			
				
					
					
						
							73 lines
						
					
					
						
							1.8 KiB
						
					
					
				
			
		
		
	
	
							73 lines
						
					
					
						
							1.8 KiB
						
					
					
				| const Stream = require('readable-stream');
 | |
| 
 | |
| // =============================================================================
 | |
| // StreamBase64 - A utility to convert to/from base64 stream
 | |
| // Note: does not buffer data, must be piped
 | |
| class StreamBase64 extends Stream.Duplex {
 | |
|   constructor() {
 | |
|     super();
 | |
| 
 | |
|     // consuming pipe streams go here
 | |
|     this.pipes = [];
 | |
|   }
 | |
| 
 | |
|   // writable
 | |
|   // event drain - if write returns false (which it won't), indicates when safe to write again.
 | |
|   // finish - end() has been called
 | |
|   // pipe(src) - pipe() has been called on readable
 | |
|   // unpipe(src) - unpipe() has been called on readable
 | |
|   // error - duh
 | |
| 
 | |
|   write(/* data, encoding */) {
 | |
|     return true;
 | |
|   }
 | |
| 
 | |
|   cork() {}
 | |
| 
 | |
|   uncork() {}
 | |
| 
 | |
|   end(/* chunk, encoding, callback */) {}
 | |
| 
 | |
|   // readable
 | |
|   // event readable - some data is now available
 | |
|   // event data - switch to flowing mode - feeds chunks to handler
 | |
|   // event end - no more data
 | |
|   // event close - optional, indicates upstream close
 | |
|   // event error - duh
 | |
|   read(/* size */) {}
 | |
| 
 | |
|   setEncoding(encoding) {
 | |
|     // causes stream.read or stream.on('data) to return strings of encoding instead of Buffer objects
 | |
|     this.encoding = encoding;
 | |
|   }
 | |
| 
 | |
|   pause() {}
 | |
| 
 | |
|   resume() {}
 | |
| 
 | |
|   isPaused() {}
 | |
| 
 | |
|   pipe(destination) {
 | |
|     // add destination to pipe list & write current buffer
 | |
|     this.pipes.push(destination);
 | |
|   }
 | |
| 
 | |
|   unpipe(destination) {
 | |
|     // remove destination from pipe list
 | |
|     this.pipes = this.pipes.filter(pipe => pipe !== destination);
 | |
|   }
 | |
| 
 | |
|   unshift(/* chunk */) {
 | |
|     // some numpty has read some data that's not for them and they want to put it back!
 | |
|     // Might implement this some day
 | |
|     throw new Error('Not Implemented');
 | |
|   }
 | |
| 
 | |
|   wrap(/* stream */) {
 | |
|     // not implemented
 | |
|     throw new Error('Not Implemented');
 | |
|   }
 | |
| }
 | |
| 
 | |
| module.exports = StreamBase64;
 |