在这里，我使用rxjs中的forkJoin来并行地订阅一个observable数组。但是我想逐个订阅它们，什么是最好的解决方案？
以下是我的代码：
var observables = [];
Observable.forkJoin(observables)
.subscribe(() => {
this.msgs = [];
this.msgs.push({
severity: 'success',
summary: 'Saved Successfully'
});
this.onSaveComplete();
}, (error: any) => this.errorMessage = <any>error);
}, (error: any) => this.errorMessage = <any>error);
答案 0 :(得分：4)
forkJoin的替代意味着您需要以顺序方式订阅可观察数组。 merge和concat是这种情况下的方法。在您的情况下，在使用merge和concat时，修改您的代码并在您的可观察数组的最开头使用扩展运算符。
var observables = [];
Observable.concat(...observables)
.subscribe(() => {
this.msgs = [];
this.msgs.push({
severity: 'success',
summary: 'Saved Successfully'
});
this.onSaveComplete();
}, (error: any) => this.errorMessage = <any>error);
}, (error: any) => this.errorMessage = <any>error);
答案 1 :(得分：0)
使用the switchMap operator制作一系列相关请求。错误将传播，您可以在链的末尾捕获或以其他方式处理它们。
worker_processes auto;
error_log logs/error.log debug;
events {
worker_connections 1024;
}
rtmp {
server {
listen 1935;
allow play all;
chunk_size 4000;
#hls - "live" full-resolution HLS videostream from our incoming encoder stream and tells where to put the HLS video manifest and video fragments
application live {
allow play all;
live on;
meta on;
#record all;
#record_path /video_recordings;
#record_unique off;
hls on;
hls_nested on;
hls_path /HLS/live;
hls_fragment 10s;
hls_type live;
allow publish 127.0.0.1;
#allow publish 192.168.2.0/24;
#allow publish 192.168.22.0/24;
#allow publish 70.62.116.192/27;
#deny publish all;
allow publish all;
# create the sampled HLS streams
# 240p - low def 288kbps / 480p standard def 448kbps / 720p hi def at 2048kbps / source
# create 3 other stored HLS variants in vod
exec ffmpeg -i rtmp://localhost:1935/$app/$name
-c:v libx264 -acodec copy -b:v 256k -vf "scale=480:trunc(ow/a/2)*2" -tune zerolatency -preset veryfast -crf 23 -g 60 -hls_list_size 0 -f flv rtmp://localhost:1935/savehls/$name_low
-c:v libx264 -acodec copy -b:v 768k -vf "scale=720:trunc(ow/a/2)*2" -tune zerolatency -preset veryfast -crf 23 -g 60 -hls_list_size 0 -f flv rtmp://localhost:1935/savehls/$name_mid
-c:v libx264 -acodec copy -b:v 1920k -vf "scale=1080:trunc(ow/a/2)*2" -tune zerolatency -preset veryfast -crf 23 -g 60 -hls_list_size 0 -f flv rtmp://localhost:1935/savehls/$name_high;
# create local mp4 archive
exec ffmpeg -i rtmp://localhost:1935/$app/$name -c:v libx264 -vprofile baseline -acodec aac -strict -2 -f mp4 /video_recordings/$name.mp4;
# exec ffmpeg -y -i $path -c:v libx264 -vprofile baseline -acodec aac -strict -2 -f mp4 $dirname/$name.mp4;
}
# hls converted streams
# - streams for mobile live and archives the HLS video manifest and video fragments
application savehls {
allow play all;
live on;
hls on;
hls_nested on;
hls_path /HLS/streams;
hls_fragment 10s;
hls_variant _low BANDWIDTH=288000; # Low bitrate, sub-SD resolution
hls_variant _mid BANDWIDTH=448000; # Medium bitrate, SD resolution
hls_variant _high BANDWIDTH=2048000; # High bitrate, HD 720p resolution
# turn off clean-up, if we want these to stay
# - note: the ts files will only have the last 5 seconds or so of ts files. so doing this is of limited help
hls_cleanup on;
}
#allows you to play your recordings of your live streams using a URL like "rtmp://my-ip:1935/vod/filename.flv"
#application vod {
#play /video_recordings;
#}
}
}
http {
include /etc/nginx/geoip/*.http.scope;
include /usr/local/nginx/conf/mime.types;
sendfile off;
tcp_nopush on;
directio 512;
# geoip variables/filters
#geoip_country /usr/share/GeoIP/GeoIP.dat;
vhost_traffic_status_zone;
map $http_user_agent $filter_user_agent {
default 'unknown';
~iPhone ios;
~Android android;
~(MSIE|Mozilla) windows;
}
vhost_traffic_status_filter_by_set_key $filter_user_agent agent::*;
#vhost_traffic_status_filter_by_set_key $geoip_country_code country::*;
server {
listen 80;
server_name xxx.160.78.xx;
# stats variables
#vhost_traffic_status_filter_by_set_key $geoip_country_code country::$server_name;
vhost_traffic_status_filter_by_set_key $filter_user_agent agent::$server_name;
# vod caches
vod_metadata_cache metadata_cache 2048m;
vod_response_cache response_cache 128m;
# vod variables
open_file_cache max=1000 inactive=5m;
open_file_cache_valid 2m;
open_file_cache_min_uses 1;
open_file_cache_errors on;
aio on;
# vod share
location /vodhls/ {
vod hls;
vod_mode local;
vod_align_segments_to_key_frames on;
alias /video_recordings/;
gzip on;
gzip_types application/vnd.apple.mpegurl;
vod_last_modified_types *;
add_header Access-Control-Allow-Headers 'origin,range,accept-encoding,referrer';
add_header Access-Control-Expose-Headers 'Server,range,Content-Length,Content-Range';
add_header Access-Control-Allow-Methods 'GET, HEAD, OPTIONS';
add_header Access-Control-Allow-Origin '*';
expires 100d;
add_header Last-Modified "Sun, 19 Nov 2000 08:52:00 GMT";
}
# hls - http-location for full-resolution desktops
# - "http://my-ip/live/my-stream-key/index.m3u8"
location /live {
default_type application/octet-stream;
types {
application/dash+xml mpd;
application/vnd.apple.mpegurl m3u8;
video/mp2t ts;
}
alias /HLS/live;
# disable cache and add CORS headers
add_header Cache-Control no-cache;
add_header 'Access-Control-Allow-Origin' '*' always;
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
add_header 'Access-Control-Allow-Headers' 'Range';
# allow CORS preflight requests
if ($request_method = 'OPTIONS') {
add_header 'Access-Control-Allow-Origin' '*';
add_header 'Access-Control-Allow-Headers' 'Range';
add_header 'Access-Control-Max-Age' 1728000;
add_header 'Content-Type' 'text/plain charset=UTF-8';
add_header 'Content-Length' 0;
return 204;
}
}
# HLS - create the http-location for mobile-device live streams and hls stream archives
# - "http://my-ip/mobile/my-stream-key/index.m3u8"
location /streams {
types {
application/dash+xml mpd;
application/vnd.apple.mpegurl m3u8;
video/mp2t ts;
}
alias /HLS/streams;
add_header Cache-Control no-cache;
add_header 'Access-Control-Allow-Origin' '*' always;
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
add_header 'Access-Control-Allow-Headers' 'Range';
}
# creates http access to vod folder
location /vod {
alias /video_recordings;
index index.html;
add_header Cache-Control no-cache;
include /usr/local/nginx/conf/mime.types;
}
#allows us to see how stats on viewers on our Nginx site using a URL like: "http://my-ip/stats"
location /mwstats {
rtmp_stat all;
rtmp_stat_stylesheet /stat.xsl;
stub_status;
access_log off;
}
location /vod_status {
vod_status;
access_log off;
}
location /mwhoststats {
vhost_traffic_status_display;
vhost_traffic_status_display_format html;
}
#allows us to host some webpages which can show our videos: "http://my-ip/my-page.html"
#location / {
#default_type text/html;
#include /usr/local/nginx/conf/mime.types;
#include /usr/local/nginx/conf/cors.conf;
#root html;
#index index.html index.htm;
#}
}
}