Make some fields in config file optional.

Especially, if log_file is not specified, will not write logs to file.

1 files changed, 31 insertions, 0 deletions

diff --git a/src/config.rs b/src/config.rs
index c7549ef..1300e9a 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -4,15 +4,46 @@ use std::io::Read;
 use serde_derive::Deserialize;
 use tracing::error;
 
+pub const DEFAULT_LOG_LEVEL: &str = "DEBUG";
+
 #[derive(Deserialize)]
 pub struct Config {
     pub bot_token: String,
+    #[serde(default = "Config::default_log_file")]
     pub log_file: String,
+    #[serde(default = "Config::default_db_file")]
     pub db_file: String,
+    #[serde(default = "Config::default_listen")]
     pub listen: String,
+    #[serde(default = "Config::default_log_level")]
     pub log_level: String,
+    #[serde(default = "Config::default_max_body_size")]
+    pub max_body_size: u64,
+}
+
+impl Config {
+    fn default_log_level() -> String {
+        String::from(DEFAULT_LOG_LEVEL)
+    }
+
+    fn default_log_file() -> String {
+        String::new() // empty string means not logging to file
+    }
+
+    fn default_max_body_size() -> u64 {
+        1024 * 16
+    }
+
+    fn default_listen() -> String {
+        String::from("localhost:8080")
+    }
+
+    fn default_db_file() -> String {
+        String::from("kimikuri.db")
+    }
 }
 
+
 impl Config {
     // Read config file. Panic if any error occurs.
     pub fn from_file(file_path: &str) -> Config {