BUG/MINOR: cache: Disable the cache if any compression filter precedes it
We need to check if any compression filter precedes the cache filter. This is
only possible when the compression is configured in the frontend while the cache
filter is configured on the backend (via a cache-store action or
explicitly). This case cannot be detected during HAProxy startup. So in such
cases, the cache is disabled.
The patch must be backported to 1.9.
diff --git a/src/cache.c b/src/cache.c
index 0002d97..a2d9375 100644
--- a/src/cache.c
+++ b/src/cache.c
@@ -234,6 +234,9 @@
st->hdrs_len = 0;
st->first_block = NULL;
filter->ctx = st;
+
+ /* Register post-analyzer on AN_RES_WAIT_HTTP */
+ filter->post_analyzers |= AN_RES_WAIT_HTTP;
}
return 1;
@@ -268,6 +271,31 @@
return 1;
}
+static int
+cache_store_post_analyze(struct stream *s, struct filter *filter, struct channel *chn,
+ unsigned an_bit)
+{
+ struct http_txn *txn = s->txn;
+ struct http_msg *msg = &txn->rsp;
+ struct cache_st *st = filter->ctx;
+
+ if (an_bit != AN_RES_WAIT_HTTP)
+ goto end;
+
+ /* Here we need to check if any compression filter precedes the cache
+ * filter. This is only possible when the compression is configured in
+ * the frontend while the cache filter is configured on the
+ * backend. This case cannot be detected during HAProxy startup. So in
+ * such cases, the cache is disabled.
+ */
+ if (st && (msg->flags & HTTP_MSGF_COMPRESSING)) {
+ pool_free(pool_head_cache_st, st);
+ filter->ctx = NULL;
+ }
+
+ end:
+ return 1;
+}
static int
cache_store_http_headers(struct stream *s, struct filter *filter, struct http_msg *msg)
@@ -616,7 +644,8 @@
struct shared_block *first = NULL;
struct cache_flt_conf *cconf = rule->arg.act.p[0];
struct shared_context *shctx = shctx_ptr(cconf->c.cache);
- struct cache_entry *object;
+ struct cache_st *cache_ctx = NULL;
+ struct cache_entry *object, *old;
/* Don't cache if the response came from a cache */
if ((obj_type(s->target) == OBJ_TYPE_APPLET) &&
@@ -636,6 +665,19 @@
if (txn->status != 200)
goto out;
+ /* Find the corresponding filter instance for the current stream */
+ list_for_each_entry(filter, &s->strm_flt.filters, list) {
+ if (FLT_ID(filter) == cache_store_flt_id && FLT_CONF(filter) == cconf) {
+ /* No filter ctx, don't cache anything */
+ if (!filter->ctx)
+ goto out;
+ cache_ctx = filter->ctx;
+ break;
+ }
+ }
+
+ /* from there, cache_ctx is always defined */
+
if (IS_HTX_STRM(s)) {
struct htx *htx = htxbuf(&s->res.buf);
struct http_hdr_ctx ctx;
@@ -755,33 +797,26 @@
}
/* register the buffer in the filter ctx for filling it with data*/
- list_for_each_entry(filter, &s->strm_flt.filters, list) {
- if (FLT_ID(filter) == cache_store_flt_id && FLT_CONF(filter) == cconf) {
- if (filter->ctx) {
- struct cache_st *cache_ctx = filter->ctx;
- struct cache_entry *old;
+ if (cache_ctx) {
+ cache_ctx->first_block = first;
- cache_ctx->first_block = first;
+ object->eb.key = (*(unsigned int *)&txn->cache_hash);
+ memcpy(object->hash, txn->cache_hash, sizeof(object->hash));
+ /* Insert the node later on caching success */
- object->eb.key = (*(unsigned int *)&txn->cache_hash);
- memcpy(object->hash, txn->cache_hash, sizeof(object->hash));
- /* Insert the node later on caching success */
-
- shctx_lock(shctx);
-
- old = entry_exist(cconf->c.cache, txn->cache_hash);
- if (old) {
- eb32_delete(&old->eb);
- old->eb.key = 0;
- }
- shctx_unlock(shctx);
+ shctx_lock(shctx);
- /* store latest value and expiration time */
- object->latest_validation = now.tv_sec;
- object->expire = now.tv_sec + http_calc_maxage(s, cconf->c.cache);
- }
- return ACT_RET_CONT;
+ old = entry_exist(cconf->c.cache, txn->cache_hash);
+ if (old) {
+ eb32_delete(&old->eb);
+ old->eb.key = 0;
}
+ shctx_unlock(shctx);
+
+ /* store latest value and expiration time */
+ object->latest_validation = now.tv_sec;
+ object->expire = now.tv_sec + http_calc_maxage(s, cconf->c.cache);
+ return ACT_RET_CONT;
}
out:
@@ -1617,6 +1652,7 @@
/* Handle channels activity */
.channel_start_analyze = cache_store_chn_start_analyze,
.channel_end_analyze = cache_store_chn_end_analyze,
+ .channel_post_analyze = cache_store_post_analyze,
/* Filter HTTP requests and responses */
.http_headers = cache_store_http_headers,