org.apache.solr.servlet.cache
Class HttpCacheHeaderUtil

java.lang.Object
  org.apache.solr.servlet.cache.HttpCacheHeaderUtil

public final class HttpCacheHeaderUtil
extends Object

Constructor Summary

HttpCacheHeaderUtil()

Method Summary

static String	calcEtag(SolrQueryRequest solrReq) Calculates a tag for the ETag header.
static long	calcLastModified(SolrQueryRequest solrReq) Calculate the appropriate last-modified time for Solr relative the current request.
static boolean	checkETagValidators(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp, Method reqMethod, String etag) Check for etag related conditional headers and set status
static void	checkHttpCachingVeto(SolrQueryResponse solrRsp, javax.servlet.http.HttpServletResponse resp, Method reqMethod) Checks if the downstream request handler wants to avoid HTTP caching of the response.
static boolean	checkLastModValidators(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp, long lastMod) Check for modify time related conditional headers and set status
static boolean	doCacheHeaderValidation(SolrQueryRequest solrReq, javax.servlet.http.HttpServletRequest req, Method reqMethod, javax.servlet.http.HttpServletResponse resp) Sets HTTP Response cache validator headers appropriately and validates the HTTP Request against these using any conditional request headers.
static boolean	isMatchingEtag(List<String> headerList, String etag) Checks if one of the tags in the list equals the given etag.
static void	sendNotModified(javax.servlet.http.HttpServletResponse res)
static void	sendPreconditionFailed(javax.servlet.http.HttpServletResponse res)
static void	setCacheControlHeader(SolrConfig conf, javax.servlet.http.HttpServletResponse resp, Method method) Set the Cache-Control HTTP header (and Expires if needed) based on the SolrConfig.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HttpCacheHeaderUtil

public HttpCacheHeaderUtil()

Method Detail

sendNotModified

public static void sendNotModified(javax.servlet.http.HttpServletResponse res)

sendPreconditionFailed

public static void sendPreconditionFailed(javax.servlet.http.HttpServletResponse res)

calcEtag

public static String calcEtag(SolrQueryRequest solrReq)

Calculates a tag for the ETag header.

Returns:

a tag

isMatchingEtag

public static boolean isMatchingEtag(List<String> headerList,
                                     String etag)

Checks if one of the tags in the list equals the given etag.

Parameters:

headerList - the ETag header related header elements

etag - the ETag to compare with

Returns:

true if the etag is found in one of the header elements - false otherwise

calcLastModified

public static long calcLastModified(SolrQueryRequest solrReq)

Calculate the appropriate last-modified time for Solr relative the current request.

Returns:

the timestamp to use as a last modified time.

setCacheControlHeader

public static void setCacheControlHeader(SolrConfig conf,
                                         javax.servlet.http.HttpServletResponse resp,
                                         Method method)

Set the Cache-Control HTTP header (and Expires if needed) based on the SolrConfig.

Parameters:

conf - The config of the SolrCore handling this request

resp - The servlet response object to modify

method - The request method (GET, POST, ...) used by this request

doCacheHeaderValidation

public static boolean doCacheHeaderValidation(SolrQueryRequest solrReq,
                                              javax.servlet.http.HttpServletRequest req,
                                              Method reqMethod,
                                              javax.servlet.http.HttpServletResponse resp)

Sets HTTP Response cache validator headers appropriately and validates the HTTP Request against these using any conditional request headers. If the request contains conditional headers, and those headers indicate a match with the current known state of the system, this method will return "true" indicating that a 304 Status code can be returned, and no further processing is needed.

Returns:

true if the request contains conditional headers, and those headers indicate a match with the current known state of the system -- indicating that a 304 Status code can be returned to the client, and no further request processing is needed.

checkETagValidators

public static boolean checkETagValidators(javax.servlet.http.HttpServletRequest req,
                                          javax.servlet.http.HttpServletResponse resp,
                                          Method reqMethod,
                                          String etag)

Check for etag related conditional headers and set status

Returns:

true if no request processing is necessary and HTTP response status has been set, false otherwise.

checkLastModValidators

public static boolean checkLastModValidators(javax.servlet.http.HttpServletRequest req,
                                             javax.servlet.http.HttpServletResponse resp,
                                             long lastMod)

Check for modify time related conditional headers and set status

Returns:

true if no request processing is necessary and HTTP response status has been set, false otherwise.

checkHttpCachingVeto

public static void checkHttpCachingVeto(SolrQueryResponse solrRsp,
                                        javax.servlet.http.HttpServletResponse resp,
                                        Method reqMethod)

Checks if the downstream request handler wants to avoid HTTP caching of the response.

Parameters:

solrRsp - The Solr response object

resp - The HTTP servlet response object

reqMethod - The HTTP request type