me.desair.tus.server.util.HttpChunkedEncodingInputStream Maven / Gradle / Ivy
package me.desair.tus.server.util;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang3.tuple.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Transparently coalesces chunks of a HTTP stream that uses Transfer-Encoding chunked.
* This {@link InputStream} wrapper also supports collecting Trailer header values that are
* sent at the end of the stream.
*
* Based on org.apache.commons.httpclient.ChunkedInputStream
*/
public class HttpChunkedEncodingInputStream extends InputStream {
private static final Logger log = LoggerFactory.getLogger(HttpChunkedEncodingInputStream.class);
/** The input stream that we're wrapping */
private InputStream in;
/** The current chunk size */
private int chunkSize = 0;
/** The current position within the current chunk */
private int pos = 0;
/** True if we'are at the beginning of stream */
private boolean bof = true;
/** True if we've reached the end of stream */
private boolean eof = false;
/** True if this stream is closed */
private boolean closed = false;
/** Map to store any trailer headers */
private Map> trailerHeaders = null;
/**
* Wrap the given input stream and store any trailing headers in the provided map.
* @param in the raw input stream
* @param trailerHeaders Map to store any trailer header values. Can be null.
*/
public HttpChunkedEncodingInputStream(
InputStream in, Map> trailerHeaders) {
if (in == null) {
throw new IllegalArgumentException("InputStream parameter may not be null");
}
this.in = in;
this.trailerHeaders = trailerHeaders;
}
/**
* Wrap the given input stream. Do not store any trailing headers.
*
* @param in the raw input stream
*/
public HttpChunkedEncodingInputStream(InputStream in) {
this(in, null);
}
/**
* Reads the next byte of data from the input stream. The value byte is
* returned as an int in the range 0 to
* 255.
*
* @return -1 of the end of the stream has been reached or the next data byte
* @throws IOException If an IO problem occurs
*/
@Override
public int read() throws IOException {
if (closed) {
throw new IOException("Attempted read from closed stream.");
}
if (eof) {
return -1;
}
if (pos >= chunkSize) {
nextChunk();
if (eof) {
return -1;
}
}
pos++;
return in.read();
}
/**
* Read some bytes from the stream.
* @param b The byte array that will hold the contents from the stream.
* @param off The offset into the byte array at which bytes will start to be placed.
* @param len the maximum number of bytes that can be returned.
* @return The number of bytes returned or -1 if the end of stream has been reached.
* @see java.io.InputStream#read(byte[], int, int)
* @throws IOException if an IO problem occurs.
*/
@Override
public int read(byte[] b, int off, int len) throws IOException {
if (closed) {
throw new IOException("Attempted read from closed stream.");
}
if (eof) {
return -1;
}
if (pos >= chunkSize) {
nextChunk();
if (eof) {
return -1;
}
}
int minLen = Math.min(len, chunkSize - pos);
int count = in.read(b, off, minLen);
pos += count;
return count;
}
/**
* Read some bytes from the stream.
* @param b The byte array that will hold the contents from the stream.
* @return The number of bytes returned or -1 if the end of stream has been reached.
* @see java.io.InputStream#read(byte[])
* @throws IOException if an IO problem occurs.
*/
@Override
public int read(byte[] b) throws IOException {
return read(b, 0, b.length);
}
/**
* Read the CRLF terminator.
* @throws IOException If an IO error occurs.
*/
private void readCRLF() throws IOException {
int cr = in.read();
int lf = in.read();
if ((cr != '\r') || (lf != '\n')) {
throw new IOException(
"CRLF expected at end of chunk: " + cr + "/" + lf);
}
}
/**
* Read the next chunk.
* @throws IOException If an IO error occurs.
*/
private void nextChunk() throws IOException {
if (!bof) {
readCRLF();
}
chunkSize = getChunkSize();
if (chunkSize < 0) {
throw new IOException("Negative chunk size");
}
bof = false;
pos = 0;
if (chunkSize == 0) {
eof = true;
parseTrailerHeaders();
}
}
/**
* Expects the stream to start with a chunk size in hex with optional
* comments after a semicolon. The line must end with a CRLF: "a3; some
* comment\r\n" Positions the stream at the start of the next line.
*
* @return the chunk size as integer
*
* @throws IOException when the chunk size could not be parsed
*/
private int getChunkSize() throws IOException {
String dataString = readChunkSizeInformation();
int separator = dataString.indexOf(';');
dataString = (separator > 0)
? dataString.substring(0, separator).trim()
: dataString.trim();
int result;
try {
result = Integer.parseInt(dataString.trim(), 16);
} catch (NumberFormatException e) {
throw new IOException("Bad chunk size: " + dataString);
}
return result;
}
private String readChunkSizeInformation() throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ChunkSizeState state = ChunkSizeState.NORMAL;
while (state != ChunkSizeState.END) {
int b = in.read();
if (b == -1) {
throw new IOException("Chunked stream ended unexpectedly");
}
state = state.process(in, baos, b);
}
//parse data
return new String(baos.toByteArray(), Charset.forName("US-ASCII"));
}
/**
* Reads and stores the Trailer headers.
* @throws IOException If an IO problem occurs
*/
private void parseTrailerHeaders() throws IOException {
if (trailerHeaders != null) {
List> footers = parseHeaders(in, StandardCharsets.US_ASCII);
for (Pair footer : footers) {
List values = trailerHeaders.get(footer.getKey());
if (values == null) {
values = new LinkedList<>();
trailerHeaders.put(footer.getKey(), values);
}
values.add(footer.getValue());
}
}
}
/**
* Upon close, this reads the remainder of the chunked message,
* leaving the underlying socket at a position to start reading the
* next response without scanning.
* @throws IOException If an IO problem occurs.
*/
@Override
public void close() throws IOException {
if (!closed) {
try {
if (!eof) {
exhaustInputStream();
}
} finally {
eof = true;
closed = true;
}
}
}
/**
* Exhaust our input stream, reading until EOF has been encountered.
*
* Note that this function is intended as a non-public utility.
* This is a little weird, but it seemed silly to make a utility
* class for this one function, so instead it is just static and
* shared that way.
*
* @throws IOException If an IO problem occurs
*/
private void exhaustInputStream() throws IOException {
// read and discard the remainder of the message
byte[] buffer = new byte[1024];
log.trace("Clearing underlying input stream, this is what was left:");
while (in.read(buffer) >= 0) {
if (log.isTraceEnabled()) {
log.trace(new String(buffer, StandardCharsets.UTF_8));
}
}
}
private List> parseHeaders(InputStream is, Charset charset) throws IOException {
List> headers = new LinkedList<>();
String name = null;
StringBuilder value = null;
String line = readLine(is, charset);
while (org.apache.commons.lang3.StringUtils.isNotBlank(line)) {
// Parse the header name and value
// Check for folded headers first
// Detect LWS-char see HTTP/1.0 or HTTP/1.1 Section 2.2
// discussion on folded headers
if (isLwsChar(line.charAt(0))) {
// we have continuation folded header
// so append value
if (value != null) {
value.append(' ');
value.append(line.trim());
}
} else {
// make sure we save the previous name, value pair if present
addHeaderValue(headers, name, value);
// Otherwise we should have normal HTTP header line
// Parse the header name and value
int colon = line.indexOf(':');
if (colon >= 0) {
name = line.substring(0, colon).trim();
value = new StringBuilder(line.substring(colon + 1).trim());
}
}
line = readLine(is, charset);
}
// make sure we save the last name,value pair if present
addHeaderValue(headers, name, value);
return headers;
}
private void addHeaderValue(List> headers, String name,
StringBuilder value) {
if (name != null) {
headers.add(Pair.of(name, value.toString()));
}
}
private boolean isLwsChar(char c) {
return c == ' ' || c == '\t';
}
private String readLine(InputStream inputStream, Charset charset) throws IOException {
byte[] rawdata = readRawLine(inputStream);
if (rawdata == null || rawdata.length == 0) {
return null;
}
// strip CR and LF from the end
int len = rawdata.length;
int offset = 0;
if (rawdata[len - 1] == '\n') {
offset++;
if (len > 1 && rawdata[len - 2] == '\r') {
offset++;
}
}
return new String(rawdata, 0, len - offset, charset);
}
private byte[] readRawLine(InputStream inputStream) throws IOException {
ByteArrayOutputStream buf = new ByteArrayOutputStream();
int ch;
while ((ch = inputStream.read()) >= 0) {
buf.write(ch);
if (ch == '\n') { // be tolerant (RFC-2616 Section 19.3)
break;
}
}
return buf.toByteArray();
}
private enum ChunkSizeState {
NORMAL {
@Override
public ChunkSizeState process(InputStream in, ByteArrayOutputStream baos, int b)
throws IOException {
ChunkSizeState newState;
if (b == '\r') {
newState = READ_CARRIAGE_RETURN;
} else {
if (b == '\"') {
newState = INSIDE_QUOTED_STRING;
} else {
newState = NORMAL;
}
baos.write(b);
}
return newState;
}
},
READ_CARRIAGE_RETURN {
@Override
public ChunkSizeState process(InputStream in, ByteArrayOutputStream baos, int b)
throws IOException {
if (b != '\n') {
// this was not CRLF
throw new IOException("Protocol violation: Unexpected"
+ " single newline character in chunk size");
}
return END;
}
},
INSIDE_QUOTED_STRING {
@Override
public ChunkSizeState process(InputStream in, ByteArrayOutputStream baos, int b)
throws IOException {
ChunkSizeState newState;
if (b == '\\') {
int nextByte = in.read();
if (nextByte >= 0) {
baos.write(nextByte);
}
newState = INSIDE_QUOTED_STRING;
} else {
if (b == '\"') {
newState = NORMAL;
} else {
newState = INSIDE_QUOTED_STRING;
}
baos.write(b);
}
return newState;
}
},
END {
@Override
public ChunkSizeState process(InputStream in, ByteArrayOutputStream baos, int b)
throws IOException {
throw new UnsupportedOperationException("The END state cannot do any processing");
}
};
public abstract ChunkSizeState process(InputStream in, ByteArrayOutputStream baos, int b)
throws IOException;
}
}