finer cache control; Expires header is now always added; default expiration for static content is a day; #37

4 files changed, 45 insertions, 8 deletions

diff --git a/src/rrd2json.c b/src/rrd2json.c
index 7a5f6df3e5..b9a123db66 100755
--- a/src/rrd2json.c
+++ b/src/rrd2json.c
@@ -259,16 +259,21 @@ void rrd_stats_all_json(BUFFER *wb)
 
 // ----------------------------------------------------------------------------
 
-// RRDR options
+// RRDR dimension options
 #define RRDR_EMPTY  	0x01 // the dimension contains / the value is empty (null)
 #define RRDR_RESET  	0x02 // the dimension contains / the value is reset
 #define RRDR_HIDDEN 	0x04 // the dimension contains / the value is hidden
 #define RRDR_NONZERO 	0x08 // the dimension contains / the value is non-zero
 
+// RRDR result options
+#define RRDR_RESULT_OPTION_ABSOLUTE 0x00000001
+#define RRDR_RESULT_OPTION_RELATIVE 0x00000002
 
 typedef struct rrdresult {
 	RRDSET *st;			// the chart this result refers to
 
+	uint32_t result_options;	// RRDR_RESULT_OPTION_*
+
 	int d;					// the number of dimensions
 	long n;					// the number of values in the arrays
 	long rows;			    // the number of rows used
@@ -1200,6 +1205,7 @@ cleanup:
 RRDR *rrd2rrdr(RRDSET *st, long points, long long after, long long before, int group_method)
 {
 	int debug = st->debug;
+	int absolute_period_requested = -1;
 
 	time_t first_entry_t = rrdset_first_entry_t(st);
 	time_t last_entry_t = rrdset_last_entry_t(st);
@@ -1207,14 +1213,22 @@ RRDR *rrd2rrdr(RRDSET *st, long points, long long after, long long before, int g
 	if(before == 0 && after == 0) {
 		before = last_entry_t;
 		after = first_entry_t;
+		absolute_period_requested = 0;
 	}
 
 	// allow relative for before and after
-	if(before <= st->update_every * st->entries)
+	if(before <= st->update_every * st->entries) {
 		before = last_entry_t + before;
+		absolute_period_requested = 0;
+	}
 
-	if(after <= st->update_every * st->entries)
+	if(after <= st->update_every * st->entries) {
 		after = last_entry_t + after;
+		absolute_period_requested = 0;
+	}
+
+	if(absolute_period_requested == -1)
+		absolute_period_requested = 1;
 
 	// make sure they are within our timeframe
 	if(before > last_entry_t) before = last_entry_t;
@@ -1314,6 +1328,11 @@ RRDR *rrd2rrdr(RRDSET *st, long points, long long after, long long before, int g
 		return r;
 	}
 
+	if(absolute_period_requested == 1)
+		r->result_options |= RRDR_RESULT_OPTION_ABSOLUTE;
+	else
+		r->result_options |= RRDR_RESULT_OPTION_RELATIVE;
+
 	// find how many dimensions we have
 	long dimensions = r->d;
 
@@ -1497,6 +1516,11 @@ int rrd2format(RRDSET *st, BUFFER *wb, BUFFER *dimensions, uint32_t format, long
 		return 500;
 	}
 
+	if(r->result_options & RRDR_RESULT_OPTION_RELATIVE)
+		wb->options |= WB_CONTENT_NO_CACHEABLE;
+	else if(r->result_options & RRDR_RESULT_OPTION_ABSOLUTE)
+		wb->options |= WB_CONTENT_CACHEABLE;
+
 	options = rrdr_check_options(r, options, (dimensions)?buffer_tostring(dimensions):NULL);
 
 	if(dimensions)
diff --git a/src/web_buffer.c b/src/web_buffer.c
index 7a169eb40a..482eb3900e 100755
--- a/src/web_buffer.c
+++ b/src/web_buffer.c
@@ -45,6 +45,7 @@ void buffer_reset(BUFFER *wb)
 	buffer_flush(wb);
 
 	wb->contenttype = CT_TEXT_PLAIN;
+	wb->options = 0;
 	wb->date = 0;
 
 	buffer_overflow_check(wb);
diff --git a/src/web_buffer.h b/src/web_buffer.h
index 4f01f19907..dfffb64949 100755
--- a/src/web_buffer.h
+++ b/src/web_buffer.h
@@ -11,10 +11,15 @@ typedef struct web_buffer {
 	size_t size;		// allocation size of buffer
 	size_t len;		// current data length in buffer
 	char *buffer;	// the buffer
-	int contenttype;
+	uint8_t contenttype;
+	uint8_t options;
 	time_t date;	// the date this content has been generated
 } BUFFER;
 
+// options
+#define WB_CONTENT_CACHEABLE			1
+#define WB_CONTENT_NO_CACHEABLE			2
+
 // content-types
 #define CT_APPLICATION_JSON				1
 #define CT_TEXT_PLAIN					2
diff --git a/src/web_client.c b/src/web_client.c
index 3312d70fef..b8eb7bf14d 100755
--- a/src/web_client.c
+++ b/src/web_client.c
@@ -1311,6 +1311,7 @@ void web_client_process(struct web_client *w) {
 		"Access-Control-Allow-Origin: *\r\n"
 		"Access-Control-Allow-Methods: GET, OPTIONS\r\n"
 		"Access-Control-Allow-Headers: accept, x-requested-with\r\n"
+		"Access-Control-Max-Age: 86400\r\n"
 		"Date: %s\r\n"
 		, code, code_msg
 		, w->keepalive?"keep-alive":"close"
@@ -1321,16 +1322,22 @@ void web_client_process(struct web_client *w) {
 	if(buffer_strlen(w->response.header))
 		buffer_strcat(w->response.header_output, buffer_tostring(w->response.header));
 
-	if(w->mode == WEB_CLIENT_MODE_NORMAL) {
+	if(w->mode == WEB_CLIENT_MODE_NORMAL && (w->response.data->options & WB_CONTENT_NO_CACHEABLE)) {
 		buffer_sprintf(w->response.header_output,
 			"Expires: %s\r\n"
 			"Cache-Control: no-cache\r\n"
-			"Access-Control-Max-Age: 0\r\n"
 			, date);
 	}
 	else {
-		buffer_strcat(w->response.header_output, "Cache-Control: public\r\n");
-		buffer_strcat(w->response.header_output, "Access-Control-Max-Age: 3600\r\n");
+		char edate[100];
+		time_t et = w->response.data->date + 86400;
+		struct tm etmbuf, *etm = gmtime_r(&et, &etmbuf);
+		strftime(edate, sizeof(edate), "%a, %d %b %Y %H:%M:%S %Z", etm);
+
+		buffer_sprintf(w->response.header_output,
+			"Expires: %s\r\n"
+			"Cache-Control: public\r\n"
+			, edate);
 	}
 
 	// if we know the content length, put it