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JensWalter/FormDataHandler.java

Created October 10, 2015 19:02
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  1. JensWalter created this gist Oct 10, 2015.
    200 changes: 200 additions & 0 deletions FormDataHandler.java
    View file
    Original file line number Diff line number Diff line change
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    package io.trivium.glue.binding.http;

    import com.sun.net.httpserver.Headers;
    import com.sun.net.httpserver.HttpExchange;
    import com.sun.net.httpserver.HttpHandler;

    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    import java.io.InputStream;
    import java.nio.charset.Charset;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.List;
    import java.util.logging.Level;
    import java.util.logging.Logger;

    public abstract class FormDataHandler implements HttpHandler {
    @Override
    public void handle(HttpExchange httpExchange) throws IOException {
    Headers headers = httpExchange.getRequestHeaders();
    String contentType = headers.getFirst("Content-Type");
    if(contentType.startsWith("multipart/form-data")){
    //found form data
    String boundary = contentType.substring(contentType.indexOf("boundary=")+9);
    // as of rfc7578 - prepend "\r\n--"
    byte[] boundaryBytes = ("\r\n--" + boundary).getBytes(Charset.forName("UTF-8"));
    byte[] payload = getInputAsBinary(httpExchange.getRequestBody());
    ArrayList<MultiPart> list = new ArrayList<>();

    List<Integer> offsets = searchBytes(payload, boundaryBytes, 0, payload.length - 1);
    for(int idx=0;idx<offsets.size();idx++){
    int startPart = offsets.get(idx);
    int endPart = payload.length;
    if(idx<offsets.size()-1){
    endPart = offsets.get(idx+1);
    }
    byte[] part = Arrays.copyOfRange(payload,startPart,endPart);
    //look for header
    int headerEnd = indexOf(part,"\r\n\r\n".getBytes(Charset.forName("UTF-8")),0,part.length-1);
    if(headerEnd>0) {
    MultiPart p = new MultiPart();
    byte[] head = Arrays.copyOfRange(part, 0, headerEnd);
    String header = new String(head);
    // extract name from header
    int nameIndex = header.indexOf("\r\nContent-Disposition: form-data; name=");
    if (nameIndex >= 0) {
    int startMarker = nameIndex + 39;
    //check for extra filename field
    int fileNameStart = header.indexOf("; filename=");
    if (fileNameStart >= 0) {
    String filename = header.substring(fileNameStart + 11, header.indexOf("\r\n", fileNameStart));
    p.filename = filename.replace('"', ' ').replace('\'', ' ').trim();
    p.name = header.substring(startMarker, fileNameStart).replace('"', ' ').replace('\'', ' ').trim();
    p.type = PartType.FILE;
    } else {
    int endMarker = header.indexOf("\r\n", startMarker);
    if (endMarker == -1)
    endMarker = header.length();
    p.name = header.substring(startMarker, endMarker).replace('"', ' ').replace('\'', ' ').trim();
    p.type = PartType.TEXT;
    }
    } else {
    // skip entry if no name is found
    continue;
    }
    // extract content type from header
    int typeIndex = header.indexOf("\r\nContent-Type:");
    if (typeIndex >= 0) {
    int startMarker = typeIndex + 15;
    int endMarker = header.indexOf("\r\n", startMarker);
    if (endMarker == -1)
    endMarker = header.length();
    p.contentType = header.substring(startMarker, endMarker).trim();
    }

    //handle content
    if (p.type == PartType.TEXT) {
    //extract text value
    byte[] body = Arrays.copyOfRange(part, headerEnd + 4, part.length);
    p.value = new String(body);
    } else {
    //must be a file upload
    p.bytes = Arrays.copyOfRange(part, headerEnd + 4, part.length);
    }
    list.add(p);
    }
    }

    handle(httpExchange,list);
    }else{
    //if no form data is present, still call handle method
    handle(httpExchange,null);
    }
    }

    public abstract void handle(HttpExchange httpExchange,List<MultiPart> parts) throws IOException;

    public static byte[] getInputAsBinary(InputStream requestStream) {
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    try {
    byte[] buf = new byte[100000];
    int bytesRead=0;
    while ((bytesRead = requestStream.read(buf)) != -1){
    //while (requestStream.available() > 0) {
    // int i = requestStream.read(buf);
    bos.write(buf, 0, bytesRead);
    }
    requestStream.close();
    bos.close();
    } catch (IOException e) {
    Logger log = Logger.getLogger(HttpUtils.class.getName());
    log.log(Level.SEVERE, "error while decoding http input stream", e);
    }
    return bos.toByteArray();
    }

    /**
    * Search bytes in byte array returns indexes within this byte-array of all
    * occurrences of the specified(search bytes) byte array in the specified
    * range
    * borrowed from https://github.com/riversun/finbin/blob/master/src/main/java/org/riversun/finbin/BinarySearcher.java
    *
    * @param srcBytes
    * @param searchBytes
    * @param searchStartIndex
    * @param searchEndIndex
    * @return result index list
    */
    public List<Integer> searchBytes(byte[] srcBytes, byte[] searchBytes, int searchStartIndex, int searchEndIndex) {
    final int destSize = searchBytes.length;
    final List<Integer> positionIndexList = new ArrayList<Integer>();
    int cursor = searchStartIndex;
    while (cursor < searchEndIndex + 1) {
    int index = indexOf(srcBytes, searchBytes, cursor, searchEndIndex);
    if (index >= 0) {
    positionIndexList.add(index);
    cursor = index + destSize;
    } else {
    cursor++;
    }
    }
    return positionIndexList;
    }

    /**
    * Returns the index within this byte-array of the first occurrence of the
    * specified(search bytes) byte array.<br>
    * Starting the search at the specified index, and end at the specified
    * index.
    * borrowed from https://github.com/riversun/finbin/blob/master/src/main/java/org/riversun/finbin/BinarySearcher.java
    *
    * @param srcBytes
    * @param searchBytes
    * @param startIndex
    * @param endIndex
    * @return
    */
    public int indexOf(byte[] srcBytes, byte[] searchBytes, int startIndex, int endIndex) {
    if (searchBytes.length == 0 || (endIndex - startIndex + 1) < searchBytes.length) {
    return -1;
    }
    int maxScanStartPosIdx = srcBytes.length - searchBytes.length;
    final int loopEndIdx;
    if (endIndex < maxScanStartPosIdx) {
    loopEndIdx = endIndex;
    } else {
    loopEndIdx = maxScanStartPosIdx;
    }
    int lastScanIdx = -1;
    label: // goto label
    for (int i = startIndex; i <= loopEndIdx; i++) {
    for (int j = 0; j < searchBytes.length; j++) {
    if (srcBytes[i + j] != searchBytes[j]) {
    continue label;
    }
    lastScanIdx = i + j;
    }
    if (endIndex < lastScanIdx || lastScanIdx - i + 1 < searchBytes.length) {
    // it becomes more than the last index
    // or less than the number of search bytes
    return -1;
    }
    return i;
    }
    return -1;
    }

    public static class MultiPart {
    public PartType type;
    public String contentType;
    public String name;
    public String filename;
    public String value;
    public byte[] bytes;
    }

    public enum PartType{
    TEXT,FILE
    }
    }