findPreviouslyCachedEntry(StoreEntry *newEntry) {
assert(newEntry->mem_obj);
return newEntry->mem_obj->request ?
- storeGetPublicByRequest(newEntry->mem_obj->request) :
+ storeGetPublicByRequest(newEntry->mem_obj->request.getRaw()) :
storeGetPublic(newEntry->mem_obj->storeId(), newEntry->mem_obj->method);
}
if (pe != NULL) {
assert(e != pe);
#if USE_HTCP
- neighborsHtcpClear(e, NULL, e->mem_obj->request, e->mem_obj->method, HTCP_CLR_INVALIDATION);
+ neighborsHtcpClear(e, nullptr, e->mem_obj->request.getRaw(), e->mem_obj->method, HTCP_CLR_INVALIDATION);
#endif
pe->release();
}
* changed.
*/
if (e->mem_obj->request)
- pe = storeGetPublicByRequestMethod(e->mem_obj->request, Http::METHOD_HEAD);
+ pe = storeGetPublicByRequestMethod(e->mem_obj->request.getRaw(), Http::METHOD_HEAD);
else
pe = storeGetPublic(e->mem_obj->storeId(), Http::METHOD_HEAD);
if (pe != NULL) {
assert(e != pe);
#if USE_HTCP
- neighborsHtcpClear(e, NULL, e->mem_obj->request, HttpRequestMethod(Http::METHOD_HEAD), HTCP_CLR_INVALIDATION);
+ neighborsHtcpClear(e, nullptr, e->mem_obj->request.getRaw(), HttpRequestMethod(Http::METHOD_HEAD), HTCP_CLR_INVALIDATION);
#endif
pe->release();
}
HttpHdrScTarget *sctusable = reply->surrogate_control->getMergedTarget(Config.Accel.surrogate_id);
if (sctusable) {
- if (sctusable->noStore() ||
+ if (sctusable->hasNoStore() ||
(Config.onoff.surrogate_is_remote
&& sctusable->noStoreRemote())) {
surrogateNoStore = true;
- entry->makePrivate();
+ // Be conservative for now and make it non-shareable because
+ // there is no enough information here to make the decision.
+ entry->makePrivate(false);
}
/* The HttpHeader logic cannot tell if the header it's parsing is a reply to an
}
}
-int
-HttpStateData::cacheableReply()
+HttpStateData::ReuseDecision::Answers
+HttpStateData::reusableReply(HttpStateData::ReuseDecision &decision)
{
HttpReply const *rep = finalReply();
HttpHeader const *hdr = &rep->header;
#define REFRESH_OVERRIDE(flag) 0
#endif
- if (EBIT_TEST(entry->flags, RELEASE_REQUEST)) {
- debugs(22, 3, "NO because " << *entry << " has been released.");
- return 0;
- }
+ if (EBIT_TEST(entry->flags, RELEASE_REQUEST))
+ return decision.make(ReuseDecision::reuseNot, "the entry has been released");
// RFC 7234 section 4: a cache MUST use the most recent response
// (as determined by the Date header field)
- if (sawDateGoBack) {
- debugs(22, 3, "NO because " << *entry << " has an older date header.");
- return 0;
- }
+ // TODO: whether such responses could be shareable?
+ if (sawDateGoBack)
+ return decision.make(ReuseDecision::reuseNot, "the response has an older date header");
// Check for Surrogate/1.0 protocol conditions
// NP: reverse-proxy traffic our parent server has instructed us never to cache
- if (surrogateNoStore) {
- debugs(22, 3, HERE << "NO because Surrogate-Control:no-store");
- return 0;
- }
+ if (surrogateNoStore)
+ return decision.make(ReuseDecision::reuseNot, "Surrogate-Control:no-store");
// RFC 2616: HTTP/1.1 Cache-Control conditions
if (!ignoreCacheControl) {
// for now we are not reliably doing that so we waste CPU re-checking request CC
// RFC 2616 section 14.9.2 - MUST NOT cache any response with request CC:no-store
- if (request && request->cache_control && request->cache_control->noStore() &&
- !REFRESH_OVERRIDE(ignore_no_store)) {
- debugs(22, 3, HERE << "NO because client request Cache-Control:no-store");
- return 0;
- }
+ if (request && request->cache_control && request->cache_control->hasNoStore() &&
+ !REFRESH_OVERRIDE(ignore_no_store))
+ return decision.make(ReuseDecision::reuseNot,
+ "client request Cache-Control:no-store");
// NP: request CC:no-cache only means cache READ is forbidden. STORE is permitted.
- if (rep->cache_control && rep->cache_control->hasNoCache() && rep->cache_control->noCache().size() > 0) {
+ if (rep->cache_control && rep->cache_control->hasNoCacheWithParameters()) {
/* TODO: we are allowed to cache when no-cache= has parameters.
* Provided we strip away any of the listed headers unless they are revalidated
* successfully (ie, must revalidate AND these headers are prohibited on stale replies).
* That is a bit tricky for squid right now so we avoid caching entirely.
*/
- debugs(22, 3, HERE << "NO because server reply Cache-Control:no-cache has parameters");
- return 0;
+ return decision.make(ReuseDecision::reuseNot,
+ "server reply Cache-Control:no-cache has parameters");
}
// NP: request CC:private is undefined. We ignore.
// NP: other request CC flags are limiters on HIT/MISS. We don't care about here.
// RFC 2616 section 14.9.2 - MUST NOT cache any response with CC:no-store
- if (rep->cache_control && rep->cache_control->noStore() &&
- !REFRESH_OVERRIDE(ignore_no_store)) {
- debugs(22, 3, HERE << "NO because server reply Cache-Control:no-store");
- return 0;
- }
+ if (rep->cache_control && rep->cache_control->hasNoStore() &&
+ !REFRESH_OVERRIDE(ignore_no_store))
+ return decision.make(ReuseDecision::reuseNot,
+ "server reply Cache-Control:no-store");
// RFC 2616 section 14.9.1 - MUST NOT cache any response with CC:private in a shared cache like Squid.
// CC:private overrides CC:public when both are present in a response.
* successfully (ie, must revalidate AND these headers are prohibited on stale replies).
* That is a bit tricky for squid right now so we avoid caching entirely.
*/
- debugs(22, 3, HERE << "NO because server reply Cache-Control:private");
- return 0;
+ return decision.make(ReuseDecision::reuseNot,
+ "server reply Cache-Control:private");
}
}
// RFC 2068, sec 14.9.4 - MUST NOT cache any response with Authentication UNLESS certain CC controls are present
// allow HTTP violations to IGNORE those controls (ie re-block caching Auth)
if (request && (request->flags.auth || request->flags.authSent)) {
- if (!rep->cache_control) {
- debugs(22, 3, HERE << "NO because Authenticated and server reply missing Cache-Control");
- return 0;
- }
+ if (!rep->cache_control)
+ return decision.make(ReuseDecision::reuseNot,
+ "authenticated and server reply missing Cache-Control");
- if (ignoreCacheControl) {
- debugs(22, 3, HERE << "NO because Authenticated and ignoring Cache-Control");
- return 0;
- }
+ if (ignoreCacheControl)
+ return decision.make(ReuseDecision::reuseNot,
+ "authenticated and ignoring Cache-Control");
bool mayStore = false;
// HTTPbis pt6 section 3.2: a response CC:public is present
- if (rep->cache_control->Public()) {
+ if (rep->cache_control->hasPublic()) {
debugs(22, 3, HERE << "Authenticated but server reply Cache-Control:public");
mayStore = true;
// HTTPbis pt6 section 3.2: a response CC:must-revalidate is present
- } else if (rep->cache_control->mustRevalidate()) {
+ } else if (rep->cache_control->hasMustRevalidate()) {
debugs(22, 3, HERE << "Authenticated but server reply Cache-Control:must-revalidate");
mayStore = true;
// HTTPbis WG verdict on this is that it is omitted from the spec due to being 'unexpected' by
// some. The caching+revalidate is not exactly unsafe though with Squids interpretation of no-cache
// (without parameters) as equivalent to must-revalidate in the reply.
- } else if (rep->cache_control->hasNoCache() && rep->cache_control->noCache().size() == 0) {
+ } else if (rep->cache_control->hasNoCacheWithoutParameters()) {
debugs(22, 3, HERE << "Authenticated but server reply Cache-Control:no-cache (equivalent to must-revalidate)");
mayStore = true;
#endif
// HTTPbis pt6 section 3.2: a response CC:s-maxage is present
- } else if (rep->cache_control->sMaxAge()) {
+ } else if (rep->cache_control->hasSMaxAge()) {
debugs(22, 3, HERE << "Authenticated but server reply Cache-Control:s-maxage");
mayStore = true;
}
- if (!mayStore) {
- debugs(22, 3, HERE << "NO because Authenticated transaction");
- return 0;
- }
+ if (!mayStore)
+ return decision.make(ReuseDecision::reuseNot, "authenticated transaction");
// NP: response CC:no-cache is equivalent to CC:must-revalidate,max-age=0. We MAY cache, and do so.
// NP: other request CC flags are limiters on HIT/MISS/REFRESH. We don't care about here.
* probably should not be cachable
*/
if ((v = hdr->getStr(Http::HdrType::CONTENT_TYPE)))
- if (!strncasecmp(v, "multipart/x-mixed-replace", 25)) {
- debugs(22, 3, HERE << "NO because Content-Type:multipart/x-mixed-replace");
- return 0;
- }
+ if (!strncasecmp(v, "multipart/x-mixed-replace", 25))
+ return decision.make(ReuseDecision::reuseNot, "Content-Type:multipart/x-mixed-replace");
+
+ // TODO: if possible, provide more specific message for each status code
+ static const char *shareableError = "shareable error status code";
+ static const char *nonShareableError = "non-shareable error status code";
+ ReuseDecision::Answers statusAnswer = ReuseDecision::reuseNot;
+ const char *statusReason = nonShareableError;
switch (rep->sline.status()) {
+
+ /* There are several situations when a non-cacheable response may be
+ * still shareable (e.g., among collapsed clients). We assume that these
+ * are 3xx and 5xx responses, indicating server problems and some of
+ * 4xx responses, common for all clients with a given cache key (e.g.,
+ * 404 Not Found or 414 URI Too Long). On the other hand, we should not
+ * share non-cacheable client-specific errors, such as 400 Bad Request
+ * or 406 Not Acceptable.
+ */
+
/* Responses that are cacheable */
case Http::scOkay:
* unless we know how to refresh it.
*/
- if (!refreshIsCachable(entry) && !REFRESH_OVERRIDE(store_stale)) {
- debugs(22, 3, "NO because refreshIsCachable() returned non-cacheable..");
- return 0;
- } else {
- debugs(22, 3, HERE << "YES because HTTP status " << rep->sline.status());
- return 1;
- }
- /* NOTREACHED */
+ if (refreshIsCachable(entry) || REFRESH_OVERRIDE(store_stale))
+ decision.make(ReuseDecision::cachePositively, "refresh check returned cacheable");
+ else
+ decision.make(ReuseDecision::doNotCacheButShare, "refresh check returned non-cacheable");
break;
/* Responses that only are cacheable if the server says so */
case Http::scFound:
case Http::scTemporaryRedirect:
- if (rep->date <= 0) {
- debugs(22, 3, HERE << "NO because HTTP status " << rep->sline.status() << " and Date missing/invalid");
- return 0;
- }
- if (rep->expires > rep->date) {
- debugs(22, 3, HERE << "YES because HTTP status " << rep->sline.status() << " and Expires > Date");
- return 1;
- } else {
- debugs(22, 3, HERE << "NO because HTTP status " << rep->sline.status() << " and Expires <= Date");
- return 0;
- }
- /* NOTREACHED */
+ if (rep->date <= 0)
+ decision.make(ReuseDecision::doNotCacheButShare, "Date is missing/invalid");
+ else if (rep->expires > rep->date)
+ decision.make(ReuseDecision::cachePositively, "Expires > Date");
+ else
+ decision.make(ReuseDecision::doNotCacheButShare, "Expires <= Date");
break;
- /* Errors can be negatively cached */
-
+ /* These responses can be negatively cached. Most can also be shared. */
case Http::scNoContent:
-
case Http::scUseProxy:
-
- case Http::scBadRequest:
-
case Http::scForbidden:
-
case Http::scNotFound:
-
case Http::scMethodNotAllowed:
-
case Http::scUriTooLong:
-
case Http::scInternalServerError:
-
case Http::scNotImplemented:
-
case Http::scBadGateway:
-
case Http::scServiceUnavailable:
-
case Http::scGatewayTimeout:
case Http::scMisdirectedRequest:
+ statusAnswer = ReuseDecision::doNotCacheButShare;
+ statusReason = shareableError;
+ // fall through to the actual decision making below
- debugs(22, 3, "MAYBE because HTTP status " << rep->sline.status());
- return -1;
-
- /* NOTREACHED */
+ case Http::scBadRequest: // no sharing; perhaps the server did not like something specific to this request
+#if USE_HTTP_VIOLATIONS
+ if (Config.negativeTtl > 0)
+ decision.make(ReuseDecision::cacheNegatively, "Config.negativeTtl > 0");
+ else
+#endif
+ decision.make(statusAnswer, statusReason);
break;
- /* Some responses can never be cached */
-
- case Http::scPartialContent: /* Not yet supported */
-
+ /* these responses can never be cached, some
+ of them can be shared though */
case Http::scSeeOther:
-
case Http::scNotModified:
-
case Http::scUnauthorized:
-
case Http::scProxyAuthenticationRequired:
-
- case Http::scInvalidHeader: /* Squid header parsing error */
-
- case Http::scHeaderTooLarge:
-
case Http::scPaymentRequired:
+ case Http::scInsufficientStorage:
+ // TODO: use more specific reason for non-error status codes
+ decision.make(ReuseDecision::doNotCacheButShare, shareableError);
+ break;
+
+ case Http::scPartialContent: /* Not yet supported. TODO: make shareable for suitable ranges */
case Http::scNotAcceptable:
- case Http::scRequestTimeout:
- case Http::scConflict:
+ case Http::scRequestTimeout: // TODO: is this shareable?
+ case Http::scConflict: // TODO: is this shareable?
case Http::scLengthRequired:
case Http::scPreconditionFailed:
case Http::scPayloadTooLarge:
case Http::scUnsupportedMediaType:
case Http::scUnprocessableEntity:
- case Http::scLocked:
+ case Http::scLocked: // TODO: is this shareable?
case Http::scFailedDependency:
- case Http::scInsufficientStorage:
case Http::scRequestedRangeNotSatisfied:
case Http::scExpectationFailed:
-
- debugs(22, 3, HERE << "NO because HTTP status " << rep->sline.status());
- return 0;
+ case Http::scInvalidHeader: /* Squid header parsing error */
+ case Http::scHeaderTooLarge:
+ decision.make(ReuseDecision::reuseNot, nonShareableError);
+ break;
default:
/* RFC 2616 section 6.1.1: an unrecognized response MUST NOT be cached. */
- debugs (11, 3, HERE << "NO because unknown HTTP status code " << rep->sline.status());
- return 0;
-
- /* NOTREACHED */
+ decision.make(ReuseDecision::reuseNot, "unknown status code");
break;
}
- /* NOTREACHED */
+ return decision.answer;
}
/// assemble a variant key (vary-mark) from the given Vary header and HTTP request
// done with Parser, now process using the HttpReply
hp = NULL;
- newrep->sources |= request->url.getScheme() == AnyP::PROTO_HTTPS ? HttpMsg::srcHttps : HttpMsg::srcHttp;
+ newrep->sources |= request->url.getScheme() == AnyP::PROTO_HTTPS ? Http::Message::srcHttps : Http::Message::srcHttp;
newrep->removeStaleWarnings();
#if USE_HTTP_VIOLATIONS
// check whether the 1xx response forwarding is allowed by squid.conf
if (Config.accessList.reply) {
- ACLFilledChecklist ch(Config.accessList.reply, originalRequest(), NULL);
+ ACLFilledChecklist ch(Config.accessList.reply, originalRequest().getRaw());
ch.reply = reply;
HTTPMSGLOCK(ch.reply);
if (ch.fastCheck() != ACCESS_ALLOWED) { // TODO: support slow lookups?
/**
* returns true if the peer can support connection pinning
*/
-bool HttpStateData::peerSupportsConnectionPinning() const
+bool
+HttpStateData::peerSupportsConnectionPinning() const
{
- const HttpReply *rep = entry->mem_obj->getReply();
- const HttpHeader *hdr = &rep->header;
- bool rc;
- String header;
-
if (!_peer)
return true;
if (!_peer->connection_auth)
return false;
+ const HttpReplyPointer rep(entry->mem_obj->getReply());
+
/*The peer supports connection pinning and the http reply status
is not unauthorized, so the related connection can be pinned
*/
reply and has in its list the "Session-Based-Authentication"
which means that the peer supports connection pinning.
*/
- if (!hdr->has(Http::HdrType::PROXY_SUPPORT))
- return false;
-
- header = hdr->getStrOrList(Http::HdrType::PROXY_SUPPORT);
- /* XXX This ought to be done in a case-insensitive manner */
- rc = (strstr(header.termedBuf(), "Session-Based-Authentication") != NULL);
+ if (rep->header.hasListMember(Http::HdrType::PROXY_SUPPORT, "Session-Based-Authentication", ','))
+ return true;
- return rc;
+ return false;
}
// Called when we parsed (and possibly adapted) the headers but
Ctx ctx = ctx_enter(entry->mem_obj->urlXXX());
HttpReply *rep = finalReply();
+ const Http::StatusCode statusCode = rep->sline.status();
entry->timestampsSet();
/* Check if object is cacheable or not based on reply code */
- debugs(11, 3, "HTTP CODE: " << rep->sline.status());
+ debugs(11, 3, "HTTP CODE: " << statusCode);
if (const StoreEntry *oldEntry = findPreviouslyCachedEntry(entry))
sawDateGoBack = rep->olderThan(oldEntry->getReply());
|| rep->header.has(Http::HdrType::HDR_X_ACCELERATOR_VARY)
#endif
) {
- const SBuf vary(httpMakeVaryMark(request, rep));
+ const SBuf vary(httpMakeVaryMark(request.getRaw(), rep));
if (vary.isEmpty()) {
- entry->makePrivate();
+ // TODO: check whether such responses are shareable.
+ // Do not share for now.
+ entry->makePrivate(false);
if (!fwd->reforwardableStatus(rep->sline.status()))
EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
varyFailure = true;
if (!fwd->reforwardableStatus(rep->sline.status()))
EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
- switch (cacheableReply()) {
+ ReuseDecision decision(entry, statusCode);
- case 1:
- entry->makePublic();
+ switch (reusableReply(decision)) {
+
+ case ReuseDecision::reuseNot:
+ entry->makePrivate(false);
break;
- case 0:
- entry->makePrivate();
+ case ReuseDecision::cachePositively:
+ entry->makePublic();
break;
- case -1:
+ case ReuseDecision::cacheNegatively:
+ entry->cacheNegatively();
+ break;
-#if USE_HTTP_VIOLATIONS
- if (Config.negativeTtl > 0)
- entry->cacheNegatively();
- else
-#endif
- entry->makePrivate();
+ case ReuseDecision::doNotCacheButShare:
+ entry->makePrivate(true);
break;
default:
assert(0);
break;
}
+ debugs(11, 3, "decided: " << decision);
}
if (!ignoreCacheControl) {
// For security reasons we do so even if storage was caused by refresh_pattern ignore-* option
// CC:must-revalidate or CC:proxy-revalidate
- const bool ccMustRevalidate = (rep->cache_control->proxyRevalidate() || rep->cache_control->mustRevalidate());
+ const bool ccMustRevalidate = (rep->cache_control->hasProxyRevalidate() || rep->cache_control->hasMustRevalidate());
// CC:no-cache (only if there are no parameters)
- const bool ccNoCacheNoParams = (rep->cache_control->hasNoCache() && rep->cache_control->noCache().size()==0);
+ const bool ccNoCacheNoParams = rep->cache_control->hasNoCacheWithoutParameters();
// CC:s-maxage=N
const bool ccSMaxAge = rep->cache_control->hasSMaxAge();
/** \par
* If the reply wants to close the connection, it takes precedence */
- if (httpHeaderHasConnDir(&rep->header, "close"))
+ static SBuf close("close", 5);
+ if (httpHeaderHasConnDir(&rep->header, close))
return COMPLETE_NONPERSISTENT_MSG;
/** \par
return statusIfComplete();
}
-#if USE_DELAY_POOLS
static void
readDelayed(void *context, CommRead const &)
{
state->flags.do_next_read = true;
state->maybeReadVirginBody();
}
-#endif
void
HttpStateData::readReply(const CommIoCbParams &io)
CommIoCbParams rd(this); // will be expanded with ReadNow results
rd.conn = io.conn;
rd.size = entry->bytesWanted(Range<size_t>(0, inBuf.spaceSize()));
-#if USE_DELAY_POOLS
- if (rd.size < 1) {
- assert(entry->mem_obj);
- /* read ahead limit */
- /* Perhaps these two calls should both live in MemObject */
+ if (rd.size <= 0) {
+ assert(entry->mem_obj);
AsyncCall::Pointer nilCall;
- if (!entry->mem_obj->readAheadPolicyCanRead()) {
- entry->mem_obj->delayRead(DeferredRead(readDelayed, this, CommRead(io.conn, NULL, 0, nilCall)));
- return;
- }
-
- /* delay id limit */
- entry->mem_obj->mostBytesAllowed().delayRead(DeferredRead(readDelayed, this, CommRead(io.conn, NULL, 0, nilCall)));
+ entry->mem_obj->delayRead(DeferredRead(readDelayed, this, CommRead(io.conn, NULL, 0, nilCall)));
return;
}
-#endif
switch (Comm::ReadNow(rd, inBuf)) {
case Comm::INPROGRESS:
}
if (ispinned && request->clientConnectionManager.valid()) {
- request->clientConnectionManager->pinConnection(serverConnection, request, _peer,
+ request->clientConnectionManager->pinConnection(serverConnection, request.getRaw(), _peer,
(request->flags.connectionAuth));
} else {
fwd->pconnPush(serverConnection, request->url.host());
// Add our own If-None-Match field if the cached entry has a strong ETag.
// copyOneHeaderFromClientsideRequestToUpstreamRequest() adds client ones.
if (request->etag.size() > 0) {
- hdr_out->addEntry(new HttpHeaderEntry(Http::HdrType::IF_NONE_MATCH, NULL,
+ hdr_out->addEntry(new HttpHeaderEntry(Http::HdrType::IF_NONE_MATCH, SBuf(),
request->etag.termedBuf()));
}
request->flags.isRanged = false;
}
- /* append Via */
- if (Config.onoff.via) {
- String strVia;
- strVia = hdr_in->getList(Http::HdrType::VIA);
- snprintf(bbuf, BBUF_SZ, "%d.%d %s",
- request->http_ver.major,
- request->http_ver.minor, ThisCache);
- strListAdd(&strVia, bbuf, ',');
- hdr_out->putStr(Http::HdrType::VIA, strVia.termedBuf());
- strVia.clean();
- }
+ hdr_out->addVia(request->http_ver, hdr_in);
if (request->flags.accelerated) {
/* Append Surrogate-Capabilities */
/** \par default.
* pass on all other header fields
* which are NOT listed by the special Connection: header. */
-
- if (strConnection.size()>0 && strListIsMember(&strConnection, e->name.termedBuf(), ',')) {
+ if (strConnection.size()>0 && strListIsMember(&strConnection, e->name, ',')) {
debugs(11, 2, "'" << e->name << "' header cropped by Connection: definition");
return;
}
/* build and pack headers */
{
HttpHeader hdr(hoRequest);
- httpBuildRequestHeader(request, entry, fwd->al, &hdr, flags);
+ httpBuildRequestHeader(request.getRaw(), entry, fwd->al, &hdr, flags);
if (request->flags.pinned && request->flags.connectionAuth)
request->flags.authSent = true;
return false;
}
- ACLFilledChecklist ch(Config.accessList.brokenPosts, originalRequest(), NULL);
+ ACLFilledChecklist ch(Config.accessList.brokenPosts, originalRequest().getRaw());
if (ch.fastCheck() != ACCESS_ALLOWED) {
debugs(11, 5, HERE << "didn't match brokenPosts");
return false;
mustStop(reason);
}
+HttpStateData::ReuseDecision::ReuseDecision(const StoreEntry *e, const Http::StatusCode code)
+ : answer(HttpStateData::ReuseDecision::reuseNot), reason(nullptr), entry(e), statusCode(code) {}
+
+HttpStateData::ReuseDecision::Answers
+HttpStateData::ReuseDecision::make(const HttpStateData::ReuseDecision::Answers ans, const char *why)
+{
+ answer = ans;
+ reason = why;
+ return answer;
+}
+
+std::ostream &operator <<(std::ostream &os, const HttpStateData::ReuseDecision &d)
+{
+ static const char *ReuseMessages[] = {
+ "do not cache and do not share", // reuseNot
+ "cache positively and share", // cachePositively
+ "cache negatively and share", // cacheNegatively
+ "do not cache but share" // doNotCacheButShare
+ };
+
+ assert(d.answer >= HttpStateData::ReuseDecision::reuseNot &&
+ d.answer <= HttpStateData::ReuseDecision::doNotCacheButShare);
+ return os << ReuseMessages[d.answer] << " because " << d.reason <<
+ "; HTTP status " << d.statusCode << " " << *(d.entry);
+}
+