GOTV+ Broadcast Server written in Go

Author

Shugo Kawamura
Github : FlowingSPDG
Twitter : @FlowingSPDG / @FlowingSPDG_EN / @_eyfl

About

This is GOTV+ broadcast server written in Go and Gin.

GOTV+ is an extension of GOTV where you use HTTP(S) to distribute instead of connecting to a regular GOTV. This makes it easy to serve many more clients around the world with high quality GOTV as you can distribute the content with CDN's.
Using tv_broadcast cvars you will enable GOTV+ on your CS:GO Server which will send fragmented data to the GOTV+ ingest (this application) which then serves them to clients which connects to it. The viewer will then watch the feed the same way you would when connecting directly to a GOTV instance.

There are a few projects similar to this. kunalpowar/csgo-broadacst(Go with mux) and S5Projects/csgo-broadcast(NodeJS/TypeScript with Express).

Usage

• Launch GOTV+ Server
  Directly using Go: go run ./main.go -addr <IP-ADDRESS>:8080 -auth gopher
  Using precompiled binary: ./gotv_plus -addr <IP-ADDRESS>:8080 -auth gopher

• Enable GOTV broadcast in CS:GO Server by adding this to server.cfg
  MATCH_ID can be what ever you want!

tv_enable 1
tv_broadcast_url "http://<IP-ADDRESS>:8080/id/MATCH_ID"
tv_broadcast_origin_auth "gopher"
tv_broadcast 1

• Connect to GOTV+ from CS:GO Client
  In console: playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID"

Tips

• You can get list of matches by accessing http://<IP-ADDRESS>:8080.
• You should configure tv_broadcast_... cvars before enable broadcast (tv_broadcast 1).
  And you may need to restart broadcast if you changed cvars. (tv_broadcast 0;tv_broadcast 1).
• playcast and tv_broadcast_url URL needs to be wrapped by double quotes (e.g. playcast "http://<IP-ADDRESS>:8080/match/MATCH_ID") because of http: colon(:) is recognized as command seprator for CS:GO.
• playcast and tv_broadcast_url does not need slash(/) in last character of URL.
  For example playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID" works properly,
  while playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID/" WILL NOT work properly.
  Because requested URL will be ending with //sync (Double-slash).

Hidden Options

There are several hidden options that are not documented. I haven't covered all of the options, but some of them are supported.

• "F" (e.g. playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID" f500) will play match from 500 fragment. CS:GO client will send request to http://<IP-ADDRESS>:8080/match/id/MATCH_ID/sync?fragment=500
• "A" (e.g. playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID" a) will play match from 1 fragment. CS:GO client will send request to http://<IP-ADDRESS>:8080/match/id/MATCH_ID/sync?fragment=1
• "C" (e.g. playcast "http://<IP-ADDRESS>:8080/match/id/MATCH_ID" c) will play match from 1 fragment. CS:GO client WILL NOT send request to http://<IP-ADDRESS>:8080/match/id/MATCH_ID/sync, CS:GO client will get 1st fragment directly.
• "B" Option / Skips dem_stop control frame(?)

Example with Public CDN

In this example we run the application with user gotv, and then use NGINX to proxy TCP/80 (HTTP) and TCP/443 (HTTPS) traffic to the application. We advice that you limit who can send POST requests (CS:GO servers external/internal IP address) directly to the service with local firewall (iptables, nftables etc), this is the reason why we limit in NGINX all requests to only GET.

We use two page rules on Cloudflare. We bypass Cache for all requests to /sync as we want that to be served directly from the application, and then cache everything on rest of the URL's.

gotv.example.com/*/sync
Cache Level: Bypass

gotv.example.com/*
Cache Level: Cache Everything

nginx config

upstream ingest {
        server <IP-ADDRESS>:8080; # Address to the gotv-plus-go application.
}

server {
	listen 80 default_server;
	listen [::]:80 default_server;

	server_name _;

	# Never cache /sync (required for Google CDN and others where you cant configure excluded URL's)
	location ~* \/sync$ {
		add_header Cache-Control "no-store";
		proxy_pass http://ingest;
	}

	# Only allow GET requests
	location / {
		limit_except GET {
			deny all;
		}
		proxy_pass http://ingest;
	}

}

server {
	listen 443 ssl;
	listen [::]:443 ssl;

	ssl_certificate /etc/ssl/cloudflare/cloudflare-cert.pem;
	ssl_certificate_key /etc/ssl/cloudflare/cloudflare-key.key;

	server_name gotv.example.com;

	# Never cache /sync (required for Google CDN and others where you cant configure excluded URL's)
	location ~* \/sync$ {
		add_header Cache-Control "no-store";
		proxy_pass http://ingest;
	}

	# Only allow GET requests
	location / {
		limit_except GET {
			deny all;
		}
		proxy_pass http://ingest;
	}
}

simple systemd service

[Unit]
Description=GOTV+ service
After=network.target
StartLimitIntervalSec=0

[Service]
Type=simple
Restart=always
RestartSec=1
User=gotv
WorkingDirectory=/path/to/gotv # Required as the application needs template
ExecStart=/path/to/gotv_plus -addr <IP-ADDRESS>:8080 -auth gopher

[Install]
WantedBy=multi-user.target

Features

• Multi matches Support
• Match management(Give specify ID for each matches for support better path like : /match/this_is_good_match_path/sync )
• Match Delete
• RtDelay/RcVage Support
• Front end support
• Internal gRPC API
• CDN Support(Tested with Cloudflare / Google Cloud CDN)
• Hidden args support (F/A). F=fragment specification w/o sync request, A = Play from [1]frag with sync request

TODO

• Dynamic auth system
• Rich Front end support
• Hidden args support (C/B). C=play from first? B=?