- `crawler/mimetype.xml`, `crawler/encoding.xml`, `crawler/robotstxt.xml`, `crawler/sitemaps.xml`
- `crawler/filter.xml`, `crawler/interval.xml`, `crawler/contentlength.xml`, `crawler/urlconverter.xml`, `crawler/container.xml`, `crawler/log.xml`

### Exception Hierarchy

All exceptions are unchecked (extend `RuntimeException` via `CrawlerSystemException`).

```

	// http://docs.aws.amazon.com/AmazonS3/latest/API/multiobjectdeleteapi.html
	if r.ContentLength <= 0 {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrMissingContentLength), r.URL)
		return
	}

	// The max. XML contains 100000 object names (each at most 1024 bytes long) + XML overhead
	const maxBodySize = 2 * 100000 * 1024

	if r.ContentLength > maxBodySize {

	Date               = "Date"
	ETag               = "ETag"
	ContentType        = "Content-Type"
	ContentMD5         = "Content-Md5"
	ContentEncoding    = "Content-Encoding"
	Expires            = "Expires"
	ContentLength      = "Content-Length"
	ContentLanguage    = "Content-Language"
	ContentRange       = "Content-Range"
	Connection         = "Connection"
	AcceptRanges       = "Accept-Ranges"
	AmzBucketRegion    = "X-Amz-Bucket-Region"

	}

	// For providing ranged content
	start, rangeLen, err = rs.GetOffsetLength(totalObjectSize)
	if err != nil {
		return err
	}

	// Set content length.
	w.Header().Set(xhttp.ContentLength, strconv.FormatInt(rangeLen, 10))
	if rs != nil {
		contentRange := fmt.Sprintf("bytes %d-%d/%d", start, start+rangeLen-1, totalObjectSize)
		w.Header().Set(xhttp.ContentRange, contentRange)
	}

		return
	}

	// Content-Length is required and should be non-zero
	if r.ContentLength <= 0 {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrMissingPart), r.URL)
		return
	}

	complMultipartUpload := &CompleteMultipartUpload{}
	if err = xmlDecoder(r.Body, complMultipartUpload, r.ContentLength); err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

    var ioe: IOException? = null

    override fun contentType(): MediaType? = "text/plain".toMediaType()

    override fun contentLength(): Long = chunk!!.size * 8L

    override fun writeTo(sink: BufferedSink) {
      try {
        var i = 0
        while (i < contentLength()) {
          sink.write(chunk!!)
          sink.flush()
          Thread.sleep(100)
          i += chunk.size
        }

    val call = client.newCall(Request(server.url("/foo")))
    val response = call.execute()

    // Body contains nothing.
    assertThat(response.body.bytes().size).isEqualTo(0)
    assertThat(response.body.contentLength()).isEqualTo(0)

    // Content-Length header doesn't exist in a 204 response.
    assertThat(response.header("content-length")).isNull()
    assertThat(response.code).isEqualTo(204)

  private RequestBody gzip(final RequestBody body) {
    return new RequestBody() {
      @Override public MediaType contentType() {
        return body.contentType();
      }

      @Override public long contentLength() {
        return -1; // We don't know the compressed length in advance!
      }

      @Override public void writeTo(BufferedSink sink) throws IOException {

}

public final class okhttp3/FormBody : okhttp3/RequestBody {
	public static final field Companion Lokhttp3/FormBody$Companion;
	public final fun -deprecated_size ()I
	public fun contentLength ()J
	public fun contentType ()Lokhttp3/MediaType;
	public final fun encodedName (I)Ljava/lang/String;
	public final fun encodedValue (I)Ljava/lang/String;
	public final fun name (I)Ljava/lang/String;

        .code(200)
        .message("OK")
        .body(
          object : ResponseBody() {
            override fun contentType(): MediaType? = null

            override fun contentLength(): Long = -1L

            override fun source(): BufferedSource = error("unexpected call")
          },
        ).trailers(
          object : TrailersSource {