feat: configure server with env variables

Author: hacdias

README.md

@@ -29,6 +29,8 @@ $ docker pull ghcr.io/ipfs/someguy:main-latest
 $ docker run --rm -it --net=host -e ghcr.io/ipfs/someguy:main-latest
 ```
 
+See [`/docs/environment-variables.md`](./docs/environment-variables.md).
+
 ## Build
 
 ```bash

docs/environment-variables.md

@@ -0,0 +1,100 @@
+# Someguy Environment Variables
+
+`someguy` ships with some implicit defaults that can be adjusted via env variables below.
+
+- [Configuration](#configuration)
+  - [`SOMEGUY_PORT`](#someguy_port)
+  - [`SOMEGUY_ACCELERATED_DHT`](#someguy_accelerated_dht)
+  - [`SOMEGUY_PROVIDER_ENDPOINTS`](#someguy_provider_endpoints)
+  - [`SOMEGUY_PEER_ENDPOINTS`](#someguy_peer_endpoints)
+  - [`SOMEGUY_IPNS_ENDPOINTS`](#someguy_ipns_endpoints)
+- [Logging](#logging)
+  - [`GOLOG_LOG_LEVEL`](#golog_log_level)
+  - [`GOLOG_LOG_FMT`](#golog_log_fmt)
+  - [`GOLOG_FILE`](#golog_file)
+  - [`GOLOG_TRACING_FILE`](#golog_tracing_file)
+
+## Configuration
+
+### `SOMEGUY_PORT`
+
+The port to listen on to.
+
+Default: `8080`
+
+### `SOMEGUY_ACCELERATED_DHT`
+
+Whether or not the Accelerated DHT is enabled or not.
+
+Default: `true`
+
+### `SOMEGUY_PROVIDER_ENDPOINTS`
+
+Comma-separated list of other Delegated Routing V1 endpoints to proxy provider requests to.
+
+Default: `https://cid.contact`
+
+### `SOMEGUY_PEER_ENDPOINTS`
+
+Comma-separated list of other Delegated Routing V1 endpoints to proxy peer requests to.
+
+Default: none
+
+### `SOMEGUY_IPNS_ENDPOINTS`
+
+Comma-separated list of other Delegated Routing V1 endpoints to proxy IPNS requests to.
+
+Default: none
+
+## Logging
+
+### `GOLOG_LOG_LEVEL`
+
+Specifies the log-level, both globally and on a per-subsystem basis. Level can
+be one of:
+
+* `debug`
+* `info`
+* `warn`
+* `error`
+* `dpanic`
+* `panic`
+* `fatal`
+
+Per-subsystem levels can be specified with `subsystem=level`.  One global level
+and one or more per-subsystem levels can be specified by separating them with
+commas.
+
+Default: `error`
+
+Example:
+
+```console
+GOLOG_LOG_LEVEL="error,someguy=debug" someguy
+```
+
+### `GOLOG_LOG_FMT`
+
+Specifies the log message format.  It supports the following values:
+
+- `color` -- human readable, colorized (ANSI) output
+- `nocolor` -- human readable, plain-text output.
+- `json` -- structured JSON.
+
+For example, to log structured JSON (for easier parsing):
+
+```bash
+export GOLOG_LOG_FMT="json"
+```
+The logging format defaults to `color` when the output is a terminal, and
+`nocolor` otherwise.
+
+### `GOLOG_FILE`
+
+Sets the file to which the logs are saved. By default, they are printed to the standard error output.
+
+### `GOLOG_TRACING_FILE`
+
+Sets the file to which the tracing events are sent. By default, tracing is disabled.
+
+Warning: Enabling tracing will likely affect performance.

main.go

@@ -23,29 +23,34 @@ func main() {
 				Name: "start",
 				Flags: []cli.Flag{
 					&cli.IntFlag{
-						Name:  "port",
-						Usage: "port to serve requests on",
-						Value: 8080,
+						Name:    "port",
+						Value:   8080,
+						EnvVars: []string{"SOMEGUY_PORT"},
+						Usage:   "port to serve requests on",
 					},
 					&cli.BoolFlag{
-						Name:  "accelerated-dht",
-						Usage: "run the accelerated DHT client",
-						Value: true,
+						Name:    "accelerated-dht",
+						Value:   true,
+						EnvVars: []string{"SOMEGUY_ACCELERATED_DHT"},
+						Usage:   "run the accelerated DHT client",
 					},
 					&cli.StringSliceFlag{
-						Name:  "provider-endpoints",
-						Usage: "other Delegated Routing V1 endpoints to proxy provider requests to",
-						Value: cli.NewStringSlice(cidContactEndpoint),
+						Name:    "provider-endpoints",
+						Value:   cli.NewStringSlice(cidContactEndpoint),
+						EnvVars: []string{"SOMEGUY_PROVIDER_ENDPOINTS"},
+						Usage:   "other Delegated Routing V1 endpoints to proxy provider requests to",
 					},
 					&cli.StringSliceFlag{
-						Name:  "peer-endpoints",
-						Usage: "other Delegated Routing V1 endpoints to proxy peer requests to",
-						Value: cli.NewStringSlice(),
+						Name:    "peer-endpoints",
+						Value:   cli.NewStringSlice(),
+						EnvVars: []string{"SOMEGUY_PEER_ENDPOINTS"},
+						Usage:   "other Delegated Routing V1 endpoints to proxy peer requests to",
 					},
 					&cli.StringSliceFlag{
-						Name:  "ipns-endpoints",
-						Usage: "other Delegated Routing V1 endpoints to proxy IPNS requests to",
-						Value: cli.NewStringSlice(),
+						Name:    "ipns-endpoints",
+						Value:   cli.NewStringSlice(),
+						EnvVars: []string{"SOMEGUY_IPNS_ENDPOINTS"},
+						Usage:   "other Delegated Routing V1 endpoints to proxy IPNS requests to",
 					},
 				},
 				Action: func(ctx *cli.Context) error {
@@ -57,13 +62,13 @@ func main() {
 				Flags: []cli.Flag{
 					&cli.StringFlag{
 						Name:  "endpoint",
-						Usage: "the Delegated Routing V1 endpoint to ask",
 						Value: cidContactEndpoint,
+						Usage: "the Delegated Routing V1 endpoint to ask",
 					},
 					&cli.BoolFlag{
 						Name:  "pretty",
-						Usage: "output data in a prettier format that may convey less information",
 						Value: false,
+						Usage: "output data in a prettier format that may convey less information",
 					},
 				},
 				Subcommands: []*cli.Command{