🐛 End file read stream if EOF is reached

src/ssn/streams/getFileFromDisks.ts

@@ -12,7 +12,7 @@ interface IGetFileFromDisksOptions {
 }
 
 function getStream(disks: string[], index: number, offset: number, length: number = Infinity) {
-  return fs.createReadStream(disks[index], { start: offset });
+  return fs.createReadStream(disks[index], { start: offset, end: offset + length - 1 });
 }
 
 /** Takes a list of ReadableStreams (the disks), as well as the offset and length, and returns a stream for just one file. */
@@ -26,12 +26,23 @@ export default async function getFileFromDisks(disks: string[], { diskStart, off
   const outputStream = new stream.PassThrough();
 
   const onData = (chunk: Buffer) => {
-    outputStream.write(chunk);
     totalRead += chunk.length;
-    //need to end if we have read beyond the file
-    //TODO: need to also shorten chunk if file ended inside it, before writing it to PassThrough.
-    if (localFileHeaderLength !== 0 && totalRead >= localFileHeaderLength + storedSize) {
-      outputStream.end();
+    //If we've reached the end, we can stop reading after this chunk
+    const readTooManyBytes = totalRead - (localFileHeaderLength + storedSize);
+    if (localFileHeaderLength !== 0 && readTooManyBytes >= 0) {
+      //We can still write the whole chunk before ending the stream
+      if (readTooManyBytes === 0) {
+        outputStream.end(chunk);
+      } else {
+        //We must shorten the chunk, write the shortened chunk and the end the stream
+        const shortenedLength = chunk.length - readTooManyBytes;
+        const shortenedChunk = new Buffer(shortenedLength);
+        shortenedChunk.fill(chunk, 0, shortenedLength);
+        outputStream.end(shortenedChunk);
+      }
+    } else {
+      //Nowhere near the end, so just write normally
+      outputStream.write(chunk);
     }
   };
   const onError = (error: any) => {
@@ -57,8 +68,7 @@ export default async function getFileFromDisks(disks: string[], { diskStart, off
 
   //Read local file header
   localFileHeaderLength = await readLocalFileHeader(outputStream);
-
-  //TODO: now that local file header has been read, restrict length of stream to storedSize
+  //now that local file header has been read, we will restrict length of stream to storedSize
 
   return outputStream;
 }

src/ssn/streams/readLocalFileHeader.ts

@@ -25,7 +25,6 @@ export default async function readLocalFileHeader(inputStream: stream.Readable):
   }
 
   //Local file header signature
-  console.log(localFileHeader);
   const magic = localFileHeader.readUInt32LE(0);
   if (magic !== 0x04034B50) {
     throw new Error(`Local file header had wrong magic; expected 0x04034B50 but got 0x${magic.toString(16).padStart(8, '0')}.`);