ProxyUtils (LittleProxy 1.1.2 API)

java.lang.Object
- org.littleshoot.proxy.impl.ProxyUtils

```
public class ProxyUtils
extends Object
```
Utilities for the proxy.

Field Summary

Fields
Modifier and Type	Field and Description
`private static com.google.common.base.Splitter`	`COMMA_SEPARATED_HEADER_VALUE_SPLITTER` Splits comma-separated header values (such as Connection) into their individual tokens.
`private static TimeZone`	`GMT`
`private static Pattern`	`HTTP_PREFIX`
`private static org.slf4j.Logger`	`LOG`
`private static String`	`PATTERN_RFC1123` Date format pattern used to parse HTTP date headers in RFC 1123 format.
`private static Set<String>`	`SHOULD_NOT_PROXY_HOP_BY_HOP_HEADERS` Hop-by-hop headers that should be removed when proxying, as defined by the HTTP 1.1 spec, section 13.5.1 (http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.5.1).

Constructor Summary

Constructors
Constructor and Description

ProxyUtils()

Constructors
Constructor and Description
`ProxyUtils()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`addVia(HttpMessage httpMessage, String alias)` Adds the Via header to specify that the message has passed through the proxy.
`private static boolean`	`checkTrueOrFalse(String val, String str1, String str2)`
`static HttpResponse`	`copyMutableResponseFields(HttpResponse original)` Make a copy of the response including all mutable fields.
`static FullHttpResponse`	`createFullHttpResponse(HttpVersion httpVersion, HttpResponseStatus status)` Creates a new `FullHttpResponse` with no body content
`static FullHttpResponse`	`createFullHttpResponse(HttpVersion httpVersion, HttpResponseStatus status, String body)` Creates a new `FullHttpResponse` with the specified String as the body contents (encoded using UTF-8).
`static FullHttpResponse`	`createFullHttpResponse(HttpVersion httpVersion, HttpResponseStatus status, String contentType, ByteBuf body, int contentLength)` Creates a new `FullHttpResponse` with the specified body.
`static HttpResponse`	`duplicateHttpResponse(HttpResponse originalResponse)` Duplicates the status line and headers of an HttpResponse object.
`static boolean`	`extractBooleanDefaultFalse(Properties props, String key)`
`static boolean`	`extractBooleanDefaultTrue(Properties props, String key)`
`static int`	`extractInt(Properties props, String key)`
`static int`	`extractInt(Properties props, String key, int defaultValue)`
`static String`	`formatDate(Date date)` Formats the given date according to the RFC 1123 pattern.
`static String`	`formatDate(Date date, String pattern)` Formats the given date according to the specified pattern.
`static List<String>`	`getAllCommaSeparatedHeaderValues(String headerName, HttpMessage httpMessage)` Retrieves all comma-separated values for headers with the specified name on the HttpMessage.
`static String`	`getHostName()` Attempts to resolve the local machine's hostname.
`static boolean`	`isChunked(HttpObject httpObject)` If an HttpObject is not the last chunk, then that means there are other chunks that will follow.
`static boolean`	`isCONNECT(HttpObject httpObject)`
`static boolean`	`isContentAlwaysEmpty(HttpMessage msg)` Returns true if the HTTP message cannot contain an entity body, according to the HTTP spec.
`static boolean`	`isFalse(String val)` Returns `true` if the specified string is either "false" or "off" ignoring case.
`static boolean`	`isHEAD(HttpRequest httpRequest)` Returns true if the specified HttpRequest is a HEAD request.
`static boolean`	`isLastChunk(HttpObject httpObject)` If an HttpObject implements the market interface LastHttpContent, it represents the last chunk of a transfer.
`static boolean`	`isResponseSelfTerminating(HttpResponse response)` Returns true if the HTTP response from the server is expected to indicate its own message length/end-of-message.
`static boolean`	`isTrue(String val)` Returns `true` if the specified string is either "true" or "on" ignoring case.
`static boolean`	`isUdtAvailable()` Determines if UDT is available on the classpath.
`static String`	`parseHostAndPort(HttpRequest httpRequest)` Parses the host and port an HTTP request is being sent to.
`static String`	`parseHostAndPort(String uri)` Parses the host and port an HTTP request is being sent to.
`static void`	`removeSdchEncoding(HttpHeaders headers)` Given an HttpHeaders instance, removes 'sdch' from the 'Accept-Encoding' header list (if it exists) and returns the modified instance.
`static boolean`	`shouldRemoveHopByHopHeader(String headerName)` Determines if the specified header should be removed from the proxied response because it is a hop-by-hop header, as defined by the HTTP 1.1 spec in section 13.5.1.
`static List<String>`	`splitCommaSeparatedHeaderValues(String headerValue)` Splits comma-separated header values into tokens.
`static String`	`stripHost(String uri)` Strips the host from a URI string.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - SHOULD_NOT_PROXY_HOP_BY_HOP_HEADERS
```
private static final Set<String> SHOULD_NOT_PROXY_HOP_BY_HOP_HEADERS
```
    Hop-by-hop headers that should be removed when proxying, as defined by the HTTP 1.1 spec, section 13.5.1 (http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.5.1). Transfer-Encoding is NOT included in this list, since LittleProxy does not typically modify the transfer encoding. See also shouldRemoveHopByHopHeader(String). Header names are stored as lowercase to make case-insensitive comparisons easier.
  - LOG
```
private static final org.slf4j.Logger LOG
```
  - GMT
```
private static final TimeZone GMT
```
  - COMMA_SEPARATED_HEADER_VALUE_SPLITTER
```
private static final com.google.common.base.Splitter COMMA_SEPARATED_HEADER_VALUE_SPLITTER
```
    Splits comma-separated header values (such as Connection) into their individual tokens.
  - PATTERN_RFC1123
```
private static final String PATTERN_RFC1123
```
    Date format pattern used to parse HTTP date headers in RFC 1123 format.
    
    See Also:
    
    Constant Field Values
  - HTTP_PREFIX
```
private static Pattern HTTP_PREFIX
```
- Constructor Detail
  - ProxyUtils
```
public ProxyUtils()
```
- Method Detail
  - stripHost
```
public static String stripHost(String uri)
```
    Strips the host from a URI string. This will turn "http://host.com/path" into "/path".
    
    Parameters:
    
    uri - The URI to transform.
    
    Returns:
    
    A string with the URI stripped.
  - formatDate
```
public static String formatDate(Date date)
```
    Formats the given date according to the RFC 1123 pattern.
    
    Parameters:
    
    date - The date to format.
    
    Returns:
    
    An RFC 1123 formatted date string.
    
    See Also:
    
    PATTERN_RFC1123
  - formatDate
```
public static String formatDate(Date date,
                                String pattern)
```
    Formats the given date according to the specified pattern. The pattern must conform to that used by the simple date format class.
    
    Parameters:
    
    date - The date to format.
    
    pattern - The pattern to use for formatting the date.
    
    Returns:
    
    A formatted date string.
    
    Throws:
    
    IllegalArgumentException - If the given date pattern is invalid.
    
    See Also:
    
    SimpleDateFormat
  - isLastChunk
```
public static boolean isLastChunk(HttpObject httpObject)
```
    If an HttpObject implements the market interface LastHttpContent, it represents the last chunk of a transfer.
    
    Parameters:
    
    httpObject -
    
    Returns:
    
    See Also:
    
    LastHttpContent
  - isChunked
```
public static boolean isChunked(HttpObject httpObject)
```
    If an HttpObject is not the last chunk, then that means there are other chunks that will follow.
    
    Parameters:
    
    httpObject -
    
    Returns:
    
    See Also:
    
    FullHttpMessage
  - parseHostAndPort
```
public static String parseHostAndPort(HttpRequest httpRequest)
```
    Parses the host and port an HTTP request is being sent to.
    
    Parameters:
    
    httpRequest - The request.
    
    Returns:
    
    The host and port string.
  - parseHostAndPort
```
public static String parseHostAndPort(String uri)
```
    Parses the host and port an HTTP request is being sent to.
    
    Parameters:
    
    uri - The URI.
    
    Returns:
    
    The host and port string.
  - copyMutableResponseFields
```
public static HttpResponse copyMutableResponseFields(HttpResponse original)
```
    Make a copy of the response including all mutable fields.
    
    Parameters:
    
    original - The original response to copy from.
    
    Returns:
    
    The copy with all mutable fields from the original.
  - addVia
```
public static void addVia(HttpMessage httpMessage,
                          String alias)
```
    Adds the Via header to specify that the message has passed through the proxy. The specified alias will be appended to the Via header line. The alias may be the hostname of the machine proxying the request, or a pseudonym. From RFC 7230, section 5.7.1:
```
         The received-by portion of the field value is normally the host and
         optional port number of a recipient server or client that
         subsequently forwarded the message.  However, if the real host is
         considered to be sensitive information, a sender MAY replace it with
         a pseudonym.
 
```
    Parameters:
    
    httpMessage - HTTP message to add the Via header to
    
    alias - the alias to provide in the Via header for this proxy
  - isTrue
```
public static boolean isTrue(String val)
```
    Returns true if the specified string is either "true" or "on" ignoring case.
    
    Parameters:
    
    val - The string in question.
    
    Returns:
    
    true if the specified string is either "true" or "on" ignoring case, otherwise false.
  - isFalse
```
public static boolean isFalse(String val)
```
    Returns true if the specified string is either "false" or "off" ignoring case.
    
    Parameters:
    
    val - The string in question.
    
    Returns:
    
    true if the specified string is either "false" or "off" ignoring case, otherwise false.
  - extractBooleanDefaultFalse
```
public static boolean extractBooleanDefaultFalse(Properties props,
                                                 String key)
```
  - extractBooleanDefaultTrue
```
public static boolean extractBooleanDefaultTrue(Properties props,
                                                String key)
```
  - extractInt
```
public static int extractInt(Properties props,
                             String key)
```
  - extractInt
```
public static int extractInt(Properties props,
                             String key,
                             int defaultValue)
```
  - isCONNECT
```
public static boolean isCONNECT(HttpObject httpObject)
```
  - isHEAD
```
public static boolean isHEAD(HttpRequest httpRequest)
```
    Returns true if the specified HttpRequest is a HEAD request.
    
    Parameters:
    
    httpRequest - http request
    
    Returns:
    
    true if request is a HEAD, otherwise false
  - checkTrueOrFalse
```
private static boolean checkTrueOrFalse(String val,
                                        String str1,
                                        String str2)
```
  - isContentAlwaysEmpty
```
public static boolean isContentAlwaysEmpty(HttpMessage msg)
```
    Returns true if the HTTP message cannot contain an entity body, according to the HTTP spec. This code is taken directly from HttpObjectDecoder.isContentAlwaysEmpty(HttpMessage).
    
    Parameters:
    
    msg - HTTP message
    
    Returns:
    
    true if the HTTP message is always empty, false if the message may have entity content.
  - isResponseSelfTerminating
```
public static boolean isResponseSelfTerminating(HttpResponse response)
```
    Returns true if the HTTP response from the server is expected to indicate its own message length/end-of-message. Returns false if the server is expected to indicate the end of the HTTP entity by closing the connection.
    This method is based on the allowed message length indicators in the HTTP specification, section 4.4:
```
         4.4 Message Length
         The transfer-length of a message is the length of the message-body as it appears in the message; that is, after any transfer-codings have been applied. When a message-body is included with a message, the transfer-length of that body is determined by one of the following (in order of precedence):

         1.Any response message which "MUST NOT" include a message-body (such as the 1xx, 204, and 304 responses and any response to a HEAD request) is always terminated by the first empty line after the header fields, regardless of the entity-header fields present in the message.
         2.If a Transfer-Encoding header field (section 14.41) is present and has any value other than "identity", then the transfer-length is defined by use of the "chunked" transfer-coding (section 3.6), unless the message is terminated by closing the connection.
         3.If a Content-Length header field (section 14.13) is present, its decimal value in OCTETs represents both the entity-length and the transfer-length. The Content-Length header field MUST NOT be sent if these two lengths are different (i.e., if a Transfer-Encoding
         header field is present). If a message is received with both a Transfer-Encoding header field and a Content-Length header field, the latter MUST be ignored.
         [LP note: multipart/byteranges support has been removed from the HTTP 1.1 spec by RFC 7230, section A.2. Since it is seldom used, LittleProxy does not check for it.]
         5.By the server closing the connection. (Closing the connection cannot be used to indicate the end of a request body, since that would leave no possibility for the server to send back a response.)
 
```
    The rules for Transfer-Encoding are clarified in RFC 7230, section 3.3.1 and 3.3.3 (3):
```
         If any transfer coding other than
         chunked is applied to a response payload body, the sender MUST either
         apply chunked as the final transfer coding or terminate the message
         by closing the connection.
 
```
    Parameters:
    
    response - the HTTP response object
    
    Returns:
    
    true if the message will indicate its own message length, or false if the server is expected to indicate the message length by closing the connection
  - getAllCommaSeparatedHeaderValues
```
public static List<String> getAllCommaSeparatedHeaderValues(String headerName,
                                                            HttpMessage httpMessage)
```
    Retrieves all comma-separated values for headers with the specified name on the HttpMessage. Any whitespace (spaces or tabs) surrounding the values will be removed. Empty values (e.g. two consecutive commas, or a value followed by a comma and no other value) will be removed; they will not appear as empty elements in the returned list. If the message contains repeated headers, their values will be added to the returned list in the order in which the headers appear. For example, if a message has headers like:
```
     Transfer-Encoding: gzip,deflate
     Transfer-Encoding: chunked
 
```
    This method will return a list of three values: "gzip", "deflate", "chunked".
    Placing values on multiple header lines is allowed under certain circumstances in RFC 2616 section 4.2, and in RFC 7230 section 3.2.2 quoted here:
```
     A sender MUST NOT generate multiple header fields with the same field
     name in a message unless either the entire field value for that
     header field is defined as a comma-separated list [i.e., #(values)]
     or the header field is a well-known exception (as noted below).

     A recipient MAY combine multiple header fields with the same field
     name into one "field-name: field-value" pair, without changing the
     semantics of the message, by appending each subsequent field value to
     the combined field value in order, separated by a comma.  The order
     in which header fields with the same field name are received is
     therefore significant to the interpretation of the combined field
     value; a proxy MUST NOT change the order of these field values when
     forwarding a message.
 
```
    Parameters:
    
    headerName - the name of the header for which values will be retrieved
    
    httpMessage - the HTTP message whose header values will be retrieved
    
    Returns:
    
    a list of single header values, or an empty list if the header was not present in the message or contained no values
  - duplicateHttpResponse
```
public static HttpResponse duplicateHttpResponse(HttpResponse originalResponse)
```
    Duplicates the status line and headers of an HttpResponse object. Does not duplicate any content associated with that response.
    
    Parameters:
    
    originalResponse - HttpResponse to be duplicated
    
    Returns:
    
    a new HttpResponse with the same status line and headers
  - getHostName
```
public static String getHostName()
```
    Attempts to resolve the local machine's hostname.
    
    Returns:
    
    the local machine's hostname, or null if a hostname cannot be determined
  - shouldRemoveHopByHopHeader
```
public static boolean shouldRemoveHopByHopHeader(String headerName)
```
    Determines if the specified header should be removed from the proxied response because it is a hop-by-hop header, as defined by the HTTP 1.1 spec in section 13.5.1. The comparison is case-insensitive, so "Connection" will be treated the same as "connection" or "CONNECTION". From http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.5.1 :
```
       The following HTTP/1.1 headers are hop-by-hop headers:
        - Connection
        - Keep-Alive
        - Proxy-Authenticate
        - Proxy-Authorization
        - TE
        - Trailers [LittleProxy note: actual header name is Trailer]
        - Transfer-Encoding [LittleProxy note: this header is not normally removed when proxying, since the proxy does not re-chunk
                            responses. The exception is when an HttpObjectAggregator is enabled, which aggregates chunked content and removes
                            the 'Transfer-Encoding: chunked' header itself.]
        - Upgrade

       All other headers defined by HTTP/1.1 are end-to-end headers.
 
```
    Parameters:
    
    headerName - the header name
    
    Returns:
    
    true if this header is a hop-by-hop header and should be removed when proxying, otherwise false
  - splitCommaSeparatedHeaderValues
```
public static List<String> splitCommaSeparatedHeaderValues(String headerValue)
```
    Splits comma-separated header values into tokens. For example, if the value of the Connection header is "Transfer-Encoding, close", this method will return "Transfer-Encoding" and "close". This method strips trims any optional whitespace from the tokens. Unlike getAllCommaSeparatedHeaderValues(String, HttpMessage), this method only operates on a single header value, rather than all instances of the header in a message.
    
    Parameters:
    
    headerValue - the un-tokenized header value (must not be null)
    
    Returns:
    
    all tokens within the header value, or an empty list if there are no values
  - isUdtAvailable
```
public static boolean isUdtAvailable()
```
    Determines if UDT is available on the classpath.
    
    Returns:
    
    true if UDT is available
  - createFullHttpResponse
```
public static FullHttpResponse createFullHttpResponse(HttpVersion httpVersion,
                                                      HttpResponseStatus status,
                                                      String body)
```
    Creates a new FullHttpResponse with the specified String as the body contents (encoded using UTF-8).
    
    Parameters:
    
    httpVersion - HTTP version of the response
    
    status - HTTP status code
    
    body - body to include in the FullHttpResponse; will be UTF-8 encoded
    
    Returns:
    
    new http response object
  - createFullHttpResponse
```
public static FullHttpResponse createFullHttpResponse(HttpVersion httpVersion,
                                                      HttpResponseStatus status)
```
    Creates a new FullHttpResponse with no body content
    
    Parameters:
    
    httpVersion - HTTP version of the response
    
    status - HTTP status code
    
    Returns:
    
    new http response object
  - createFullHttpResponse
```
public static FullHttpResponse createFullHttpResponse(HttpVersion httpVersion,
                                                      HttpResponseStatus status,
                                                      String contentType,
                                                      ByteBuf body,
                                                      int contentLength)
```
    Creates a new FullHttpResponse with the specified body.
    
    Parameters:
    
    httpVersion - HTTP version of the response
    
    status - HTTP status code
    
    contentType - the Content-Type of the body
    
    body - body to include in the FullHttpResponse; if null
    
    contentLength - number of bytes to send in the Content-Length header; should equal the number of bytes in the ByteBuf
    
    Returns:
    
    new http response object
  - removeSdchEncoding
```
public static void removeSdchEncoding(HttpHeaders headers)
```
    Given an HttpHeaders instance, removes 'sdch' from the 'Accept-Encoding' header list (if it exists) and returns the modified instance. Removes all occurrences of 'sdch' from the 'Accept-Encoding' header.
    
    Parameters:
    
    headers - The headers to modify.

Class ProxyUtils

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SHOULD_NOT_PROXY_HOP_BY_HOP_HEADERS

LOG

GMT

COMMA_SEPARATED_HEADER_VALUE_SPLITTER

PATTERN_RFC1123

HTTP_PREFIX

Constructor Detail

ProxyUtils

Method Detail

stripHost

formatDate

formatDate

isLastChunk

isChunked

parseHostAndPort

parseHostAndPort

copyMutableResponseFields

addVia

isTrue

isFalse

extractBooleanDefaultFalse

extractBooleanDefaultTrue

extractInt

extractInt

isCONNECT

isHEAD

checkTrueOrFalse

isContentAlwaysEmpty

isResponseSelfTerminating

getAllCommaSeparatedHeaderValues

duplicateHttpResponse

getHostName

shouldRemoveHopByHopHeader

splitCommaSeparatedHeaderValues

isUdtAvailable

createFullHttpResponse

createFullHttpResponse

createFullHttpResponse

removeSdchEncoding