Merge pull request #43 from rust-lang/runtime-feature-flags

Runtime feature flags

Author: technetos

Cargo.lock

@@ -17,3 +17,4 @@ serde_derive = "1.0"
 lazy_static = "1.4.0"
 log = "0.4.0"
 env_logger = "0.7.1"
+envy = "0.4"

Cargo.toml

@@ -2,7 +2,7 @@ FROM ubuntu:16.04
 
 # Add the PostgreSQL PGP key to verify their Debian packages.
 # It should be the same key as https://www.postgresql.org/media/keys/ACCC4CF8.asc
-RUN apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8
+RUN apt-key adv --keyserver hkp://pool.sks-keyservers.net:80 --recv-keys B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8
 
 # Add PostgreSQL's repository. It contains the most recent stable release
 #     of PostgreSQL, ``9.5``.

postgres-docker/Dockerfile

@@ -19,17 +19,25 @@ mod welcome;
 use crate::db::DB;
 use commands::{Args, Commands};
 use diesel::prelude::*;
+use envy;
+use serde::Deserialize;
 use serenity::{model::prelude::*, prelude::*};
 
 pub(crate) type Result = crate::commands::Result<()>;
 
-fn init_data() -> Result {
+#[derive(Deserialize)]
+struct Config {
+    tags: bool,
+    crates: bool,
+    discord_token: String,
+    mod_id: String,
+    talk_id: String,
+    wg_and_teams_id: Option<String>,
+}
+
+fn init_data(config: &Config) -> Result {
     use crate::schema::roles;
     info!("Loading data into database");
-    let mod_role = std::env::var("MOD_ID").map_err(|_| "MOD_ID env var not found")?;
-    let talk_role = std::env::var("TALK_ID").map_err(|_| "TALK_ID env var not found")?;
-    let wg_and_teams_role =
-        std::env::var("WG_AND_TEAMS_ID").map_err(|_| "WG_AND_TEAMS_ID env var not found")?;
 
     let conn = DB.get()?;
 
@@ -48,9 +56,16 @@ fn init_data() -> Result {
         .build_transaction()
         .read_write()
         .run::<_, Box<dyn std::error::Error>, _>(|| {
-            upsert_role("mod", &mod_role)?;
-            upsert_role("talk", &talk_role)?;
-            upsert_role("wg_and_teams", &wg_and_teams_role)?;
+            upsert_role("mod", &config.mod_id)?;
+            upsert_role("talk", &config.talk_id)?;
+
+            if config.tags || config.crates {
+                let wg_and_teams_role = config
+                    .wg_and_teams_id
+                    .as_ref()
+                    .ok_or_else(|| "missing value for field wg_and_teams_id.\n\nIf you enabled tags or crates then you need the WG_AND_TEAMS_ID env var.")?;
+                upsert_role("wg_and_teams", &wg_and_teams_role)?;
+            }
 
             Ok(())
         })?;
@@ -59,30 +74,34 @@ fn init_data() -> Result {
 }
 
 fn app() -> Result {
+    let config = envy::from_env::<Config>()?;
+
     info!("starting...");
-    let token = std::env::var("DISCORD_TOKEN")
-        .map_err(|_| "missing environment variable: DISCORD_TOKEN")?;
 
     let _ = db::run_migrations()?;
 
-    let _ = init_data()?;
+    let _ = init_data(&config)?;
 
     let mut cmds = Commands::new();
 
-    // Tags
-    cmds.add("?tags delete {key}", tags::delete);
-    cmds.add("?tags create {key} value...", tags::post);
-    cmds.add("?tags help", tags::help);
-    cmds.add("?tags", tags::get_all);
-    cmds.add("?tag {key}", tags::get);
+    if config.tags {
+        // Tags
+        cmds.add("?tags delete {key}", tags::delete);
+        cmds.add("?tags create {key} value...", tags::post);
+        cmds.add("?tags help", tags::help);
+        cmds.add("?tags", tags::get_all);
+        cmds.add("?tag {key}", tags::get);
+    }
 
-    // crates.io
-    cmds.add("?crate help", crates::help);
-    cmds.add("?crate query...", crates::search);
+    if config.crates {
+        // crates.io
+        cmds.add("?crate help", crates::help);
+        cmds.add("?crate query...", crates::search);
 
-    // docs.rs
-    cmds.add("?docs help", crates::doc_help);
-    cmds.add("?docs query...", crates::doc_search);
+        // docs.rs
+        cmds.add("?docs help", crates::doc_help);
+        cmds.add("?docs query...", crates::doc_search);
+    }
 
     // Slow mode.
     // 0 seconds disables slowmode
@@ -104,7 +123,7 @@ fn app() -> Result {
         Ok(())
     });
 
-    let mut client = Client::new_with_extras(&token, |e| {
+    let mut client = Client::new_with_extras(&config.discord_token, |e| {
         e.event_handler(Messages { cmds });
         e.raw_event_handler(Events);
         e
@@ -118,8 +137,8 @@ fn app() -> Result {
 fn main() {
     env_logger::init();
 
-    if let Err(err) = app() {
-        eprintln!("error: {}", err);
+    if let Err(e) = app() {
+        error!("{}", e);
         std::process::exit(1);
     }
 }