API to retrieve NoStore set by plugins (#7439) (#7763)

(cherry picked from commit 6318dba)

Author: vmamidi

include/ts/ts.h

@@ -1291,6 +1291,13 @@ tsapi void TSHttpTxnReqCacheableSet(TSHttpTxn txnp, int flag);
 */
 tsapi TSReturnCode TSHttpTxnServerRespNoStoreSet(TSHttpTxn txnp, int flag);
 
+/** Get flag indicating whether or not to cache the server response for
+    given TSHttpTxn
+    @param txnp The transaction whose server response you do not want to store.
+
+    @return TS_SUCCESS.
+*/
+tsapi bool TSHttpTxnServerRespNoStoreGet(TSHttpTxn txnp);
 tsapi TSReturnCode TSFetchPageRespGet(TSHttpTxn txnp, TSMBuffer *bufp, TSMLoc *offset);
 tsapi char *TSFetchRespGet(TSHttpTxn txnp, int *length);
 tsapi TSReturnCode TSHttpTxnCacheLookupStatusGet(TSHttpTxn txnp, int *lookup_status);

src/traffic_server/InkAPI.cc

@@ -5247,6 +5247,15 @@ TSHttpTxnServerRespNoStoreSet(TSHttpTxn txnp, int flag)
   return TS_SUCCESS;
 }
 
+bool
+TSHttpTxnServerRespNoStoreGet(TSHttpTxn txnp)
+{
+  sdk_assert(sdk_sanity_check_txn(txnp) == TS_SUCCESS);
+
+  HttpTransact::State *s = &(((HttpSM *)txnp)->t_state);
+  return s->api_server_response_no_store;
+}
+
 TSReturnCode
 TSHttpTxnServerRespIgnore(TSHttpTxn txnp)
 {