429 and 503 codes can, and often do (e.g. all Google Cloud
Storage URLs can), return a Retry-After header with the error,
indicating how long to wait, in seconds, before retrying again.
If it is not respected by, for example, using our default backoff
stratetgy instead, chances of success are very unlikely.
This adds an AVOption to respect that header.
Signed-off-by: Derek Buitenhuis <derek.buitenh...@gmail.com>
---
libavformat/http.c | 12 ++++++++++++
libavformat/version.h | 2 +-
2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/libavformat/http.c b/libavformat/http.c
index e7603037f4..8f092f108d 100644
--- a/libavformat/http.c
+++ b/libavformat/http.c
@@ -138,6 +138,8 @@ typedef struct HTTPContext {
char *new_location;
AVDictionary *redirect_cache;
uint64_t filesize_from_content_range;
+ int respect_retry_after;
+ int retry_after;
} HTTPContext;
#define OFFSET(x) offsetof(HTTPContext, x)
@@ -176,6 +178,7 @@ static const AVOption options[] = {
{ "reconnect_on_http_error", "list of http status codes to reconnect on",
OFFSET(reconnect_on_http_error), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, D },
{ "reconnect_streamed", "auto reconnect streamed / non seekable streams",
OFFSET(reconnect_streamed), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, D },
{ "reconnect_delay_max", "max reconnect delay in seconds after which to give
up", OFFSET(reconnect_delay_max), AV_OPT_TYPE_INT, { .i64 = 120 }, 0, UINT_MAX/1000/1000, D },
+ { "respect_retry_after", "respect the Retry-After header when retrying
connections", OFFSET(respect_retry_after), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, D },
{ "listen", "listen on HTTP", OFFSET(listen), AV_OPT_TYPE_INT, { .i64 = 0
}, 0, 2, D | E },
{ "resource", "The resource requested by a client", OFFSET(resource),
AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
{ "reply_code", "The http status code to return to a client",
OFFSET(reply_code), AV_OPT_TYPE_INT, { .i64 = 200}, INT_MIN, 599, E},
@@ -386,6 +389,13 @@ redo:
reconnect_delay > s->reconnect_delay_max)
goto fail;
+ if (s->respect_retry_after && s->retry_after > 0) {
+ reconnect_delay = s->retry_after;
+ if (reconnect_delay > s->reconnect_delay_max)
+ goto fail;
+ s->retry_after = 0;
+ }
+
av_log(h, AV_LOG_WARNING, "Will reconnect at %"PRIu64" in %d
second(s).\n", off, reconnect_delay);
ret = ff_network_sleep_interruptible(1000U * 1000 * reconnect_delay,
&h->interrupt_callback);
if (ret != AVERROR(ETIMEDOUT))
@@ -1231,6 +1241,8 @@ static int process_line(URLContext *h, char *line, int
line_count, int *parsed_h
parse_expires(s, p);
} else if (!av_strcasecmp(tag, "Cache-Control")) {
parse_cache_control(s, p);
+ } else if (!av_strcasecmp(tag, "Retry-After")) {
+ s->retry_after = strtoull(p, NULL, 10);
