[#667] Add docs for listen_domains config param

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

README.md

@@ -54,6 +54,33 @@ $ S3_GW_PEERS_0_ADDRESS=grpcs://192.168.130.72:8080 \
   neofs-s3-gw
 ```
 
+## Domains
+
+By default, s3-gw enable only `path-style access`. 
+To be able to use both: `virtual-hosted-style` and `path-style` access you must configure `listen_domains`:
+
+```shell
+$ neofs-s3-gw -p 192.168.130.72:8080 --wallet wallet.json --listen_domains your.first.domain --listen_domains your.second.domain
+```
+
+So now you can use (e.g. `HeadBucket`. Make sure DNS is properly configured):
+
+```shell
+$ curl --head http://bucket-name.your.first.domain:8080
+HTTP/1.1 200 OK
+...
+```
+
+or
+
+```shell
+$ curl --head http://your.second.domain:8080/bucket-name
+HTTP/1.1 200 OK
+...
+```
+
+Also, you can configure domains using `.env` variables or `yaml` file.
+
 ## Documentation
 
 - [Configuration](./docs/configuration.md)

cmd/s3-gw/app.go

@@ -265,7 +265,7 @@ func (a *App) Server(ctx context.Context) {
 
 	router := mux.NewRouter().SkipClean(true).UseEncodedPath()
 	// Attach S3 API:
-	domains := fetchDomains(a.cfg)
+	domains := a.cfg.GetStringSlice(cfgListenDomains)
 	a.log.Info("fetch domains, prepare to use API",
 		zap.Strings("domains", domains))
 	api.Attach(router, domains, a.maxClients, a.api, a.ctr, a.log)

cmd/s3-gw/app_settings.go

@@ -161,21 +161,6 @@ func fetchPeers(l *zap.Logger, v *viper.Viper) []pool.NodeParam {
 	return nodes
 }
 
-func fetchDomains(v *viper.Viper) []string {
-	cnt := v.GetInt(cfgListenDomains + ".count")
-	res := make([]string, 0, cnt)
-	for i := 0; ; i++ {
-		domain := v.GetString(cfgListenDomains + "." + strconv.Itoa(i))
-		if domain == "" {
-			break
-		}
-
-		res = append(res, domain)
-	}
-
-	return res
-}
-
 func newSettings() *viper.Viper {
 	v := viper.New()
 
@@ -216,7 +201,7 @@ func newSettings() *viper.Viper {
 	flags.StringP(cfgRPCEndpoint, "r", "", "set RPC endpoint")
 	resolveMethods := flags.StringSlice(cfgResolveOrder, []string{resolver.DNSResolver}, "set bucket name resolve order")
 
-	domains := flags.StringArrayP(cfgListenDomains, "d", nil, "set domains to be listened")
+	domains := flags.StringSliceP(cfgListenDomains, "d", nil, "set domains to be listened")
 
 	// set defaults:
 
@@ -264,11 +249,7 @@ func newSettings() *viper.Viper {
 	}
 
 	if domains != nil && len(*domains) > 0 {
-		for i := range *domains {
+		v.SetDefault(cfgListenDomains, *domains)
-			v.SetDefault(cfgListenDomains+"."+strconv.Itoa(i), (*domains)[i])
-		}
-
-		v.SetDefault(cfgListenDomains+".count", len(*domains))
 	}
 
 	switch {

config/config.env

@@ -28,6 +28,9 @@ S3_GW_LISTEN_ADDRESS=0.0.0.0:8080
 S3_GW_TLS_CERT_FILE=/path/to/tls/cert
 S3_GW_TLS_KEY_FILE=/path/to/tls/key
 
+# Domains to be able to use virtual-hosted-style access to bucket.
+S3_GW_LISTEN_DOMAINS=s3dev.neofs.devenv
+
 # Config file
 S3_GW_CONFIG=/path/to/config/yaml
 

config/config.yaml

@@ -31,6 +31,10 @@ tls:
   cert_file: /path/to/cert
   key_file: /path/to/key
 
+# Domains to be able to use virtual-hosted-style access to bucket.
+listen_domains:
+  - s3dev.neofs.devenv
+
 logger:
   level: debug
 

docs/configuration.md

@@ -140,6 +140,10 @@ There are some custom types used for brevity:
 ```yaml
 listen_address: 0.0.0.0:8084
 
+listen_domains:
+   - s3dev.neofs.devenv
+   - s3dev2.neofs.devenv
+
 rpc_endpoint: http://morph-chain.neofs.devenv:30333
 resolve_order:
   - nns
@@ -163,6 +167,7 @@ allowed_access_key_id_prefixes:
 | Parameter                        | Type       | Default value  | Description                                                                                                                                                                                                       |
 |----------------------------------|------------|----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `listen_address`                 | `string`   | `0.0.0.0:8080` | The address that the gateway is listening on.                                                                                                                                                                     |
+| `listen_domains`                 | `[]string` |                | Domains to be able to use virtual-hosted-style access to bucket.                                                                                                                                                  |
 | `rpc_endpoint`                   | `string`   |                | The address of the RPC host to which the gateway connects to resolve bucket names (required to use the `nns` resolver).                                                                                           |
 | `resolve_order`                  | `[]string` | `[dns]`        | Order of bucket name resolvers to use. Available resolvers: `dns`, `nns`.                                                                                                                                         |                                                                                                                                                                           |
 | `connect_timeout`                | `duration` | `10s`          | Timeout to connect to a node.                                                                                                                                                                                     |