diff mbox series

[FFmpeg-devel,4/6,v2] avformat/http: Add support for Retry-After header

Message ID 20240415164933.110933-1-derek.buitenhuis@gmail.com
State New
Headers show
Series None | expand

Commit Message

Derek Buitenhuis April 15, 2024, 4:49 p.m. UTC 
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.buitenhuis@gmail.com>
---
 libavformat/http.c    | 12 ++++++++++++
 libavformat/version.h |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

Comments

Stefano Sabatini April 15, 2024, 5:33 p.m. UTC | #1 
On date Monday 2024-04-15 17:49:33 +0100, Derek Buitenhuis wrote:
> 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.buitenhuis@gmail.com>
> ---
>  libavformat/http.c    | 12 ++++++++++++
>  libavformat/version.h |  2 +-
>  2 files changed, 13 insertions(+), 1 deletion(-)

missing doc/protocols.texi update
Derek Buitenhuis April 16, 2024, 1:59 p.m. UTC | #2 
On 4/15/2024 6:33 PM, Stefano Sabatini wrote:
> missing doc/protocols.texi update

Sent patch 7 and 8 to address this.

- Derek
diff mbox series

Patch

diff --git a/libavformat/http.c b/libavformat/http.c
index e7603037f4..5ed481b63a 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;
+    unsigned 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 = strtoul(p, NULL, 10);
         }
     }
     return 1;
diff --git a/libavformat/version.h b/libavformat/version.h
index 7ff1483912..ee91990360 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,7 +32,7 @@ 
 #include "version_major.h"
 
 #define LIBAVFORMAT_VERSION_MINOR   3
-#define LIBAVFORMAT_VERSION_MICRO 100
+#define LIBAVFORMAT_VERSION_MICRO 101
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \