1 files changed, 126 insertions, 0 deletions
diff --git a/src/config/environment.rs b/src/config/environment.rs
new file mode 100644
index 0000000..c4d2c06
--- /dev/null
+++ b/src/config/environment.rs
@@ -0,0 +1,126 @@
+// Copyright 2017-2018 int08h LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+extern crate hex;
+
+use std::env;
+use std::net::SocketAddr;
+use std::time::Duration;
+
+use Error;
+use config::ServerConfig;
+use config::{DEFAULT_BATCH_SIZE, DEFAULT_STATUS_INTERVAL};
+
+///
+/// Obtain a Roughenough server configuration ([ServerConfig](trait.ServerConfig.html))
+/// from environment variables.
+///
+///   Config parameter | Environment Variable
+///   ---------------- | --------------------
+///   port             | `ROUGHENOUGH_PORT`
+///   interface        | `ROUGHENOUGH_INTERFACE`
+///   seed             | `ROUGHENOUGH_SEED`
+///   batch_size       | `ROUGHENOUGH_BATCH_SIZE`
+///   status_interval  | `ROUGHENOUGH_STATUS_INTERVAL`
+///
+pub struct EnvironmentConfig {
+    port: u16,
+    interface: String,
+    seed: Vec<u8>,
+    batch_size: u8,
+    status_interval: Duration,
+}
+
+const ROUGHENOUGH_PORT: &str = "ROUGHENOUGH_PORT";
+const ROUGHENOUGH_INTERFACE: &str = "ROUGHENOUGH_INTERFACE";
+const ROUGHENOUGH_SEED: &str = "ROUGHENOUGH_SEED";
+const ROUGHENOUGH_BATCH_SIZE: &str = "ROUGHENOUGH_BATCH_SIZE";
+const ROUGHENOUGH_STATUS_INTERVAL: &str = "ROUGHENOUGH_STATUS_INTERVAL";
+
+impl EnvironmentConfig {
+    pub fn new() -> Self {
+        let mut cfg = EnvironmentConfig {
+            port: 0,
+            interface: "".to_string(),
+            seed: Vec::new(),
+            batch_size: DEFAULT_BATCH_SIZE,
+            status_interval: DEFAULT_STATUS_INTERVAL,
+        };
+
+        if let Ok(port) = env::var(ROUGHENOUGH_PORT) {
+            cfg.port = port
+                .parse()
+                .expect(format!("invalid port: {}", port).as_ref());
+        };
+
+        if let Ok(interface) = env::var(ROUGHENOUGH_INTERFACE) {
+            cfg.interface = interface.to_string();
+        };
+
+        if let Ok(seed) = env::var(ROUGHENOUGH_SEED) {
+            cfg.seed = hex::decode(&seed).expect(
+                format!(
+                    "invalid seed value: {}\n'seed' should be 32 byte hex value",
+                    seed
+                ).as_ref(),
+            );
+        };
+
+        if let Ok(batch_size) = env::var(ROUGHENOUGH_BATCH_SIZE) {
+            cfg.batch_size = batch_size
+                .parse()
+                .expect(format!("invalid batch_size: {}", batch_size).as_ref());
+        };
+
+        if let Ok(status_interval) = env::var(ROUGHENOUGH_STATUS_INTERVAL) {
+            let val: u16 = status_interval
+                .parse()
+                .expect(format!("invalid status_interval: {}", status_interval).as_ref());
+
+            cfg.status_interval = Duration::from_secs(val as u64);
+        };
+
+        cfg
+    }
+}
+
+impl ServerConfig for EnvironmentConfig {
+    fn interface(&self) -> &str {
+        self.interface.as_ref()
+    }
+
+    fn port(&self) -> u16 {
+        self.port
+    }
+
+    fn seed(&self) -> &[u8] {
+        &self.seed
+    }
+
+    fn batch_size(&self) -> u8 {
+        self.batch_size
+    }
+
+    fn status_interval(&self) -> Duration {
+        self.status_interval
+    }
+
+    fn socket_addr(&self) -> Result<SocketAddr, Error> {
+        let addr = format!("{}:{}", self.interface, self.port);
+        match addr.parse() {
+            Ok(v) => Ok(v),
+            Err(_) => Err(Error::InvalidConfiguration(addr)),
+        }
+    }
+}