Set up a file logger

Get a file path from the `LOG_FILE` environment variable and use it for
log output.

Call `database::get_database_connection()` and log the error if it
fails.

Worried about exiting early from the FastCGI program, as DreamHost says
this causes problems
(https://help.dreamhost.com/hc/en-us/articles/217298967). But I don't
see how the program can continue without a database connection.

Return a `Result` from `main()` because it's easier to use the `?`
operator for errors that happen before logging is initialised.

6 files changed, 77 insertions, 4 deletions

diff --git a/license-generator/Cargo.lock b/license-generator/Cargo.lock
index 9510eb7..09cad51 100644
--- a/license-generator/Cargo.lock
+++ b/license-generator/Cargo.lock
@@ -284,9 +284,19 @@ version = "0.0.1"
 dependencies = [
  "error-chain 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "fastcgi 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "mysql 14.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "sha1 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "simplelog 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "log"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -615,6 +625,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "simplelog"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "term 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "smallvec"
 version = "0.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -633,6 +653,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "term"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "thread_local"
 version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -808,6 +837,7 @@ dependencies = [
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)" = "76e3a3ef172f1a0b9a9ff0dd1491ae5e6c948b94479a3021819ba7d860c8645d"
+"checksum log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c84ec4b527950aa83a329754b01dbe3f58361d1c5efacd1f6d68c494d08a17c6"
 "checksum matches 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
 "checksum memchr 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0a3eb002f0535929f1199681417029ebea04aadc0c7a4224b46be99c7f5d6a16"
 "checksum miniz-sys 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "0300eafb20369952951699b68243ab4334f4b10a88f411c221d444b36c40e649"
@@ -842,8 +872,10 @@ dependencies = [
 "checksum serde_json 1.0.32 (registry+https://github.com/rust-lang/crates.io-index)" = "43344e7ce05d0d8280c5940cabb4964bea626aa58b1ec0e8c73fa2a8512a38ce"
 "checksum sha1 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2579985fda508104f7587689507983eadd6a6e84dd35d6d115361f530916fa0d"
 "checksum sha2 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9eb6be24e4c23a84d7184280d2722f7f2731fcdd4a9d886efbfe4413e4847ea0"
+"checksum simplelog 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2e95345f185d5adeb8ec93459d2dc99654e294cc6ccf5b75414d8ea262de9a13"
 "checksum smallvec 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "153ffa32fd170e9944f7e0838edf824a754ec4c1fc64746fcc9fe1f8fa602e5d"
 "checksum syn 0.15.18 (registry+https://github.com/rust-lang/crates.io-index)" = "90c39a061e2f412a9f869540471ab679e85e50c6b05604daf28bc3060f75c430"
+"checksum term 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5e6b677dd1e8214ea1ef4297f85dbcbed8e8cdddb561040cc998ca2551c37561"
 "checksum thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
 "checksum time 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)" = "d825be0eb33fda1a7e68012d51e9c7f451dc1a69391e7fdc197060bb8c56667b"
 "checksum twox-hash 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4f85be565a110ed72ed7048cf56570db04ce0a592c98aa59b7dacde3e5718750"
diff --git a/license-generator/Cargo.toml b/license-generator/Cargo.toml
index 89b54fa..472f585 100644
--- a/license-generator/Cargo.toml
+++ b/license-generator/Cargo.toml
@@ -5,9 +5,11 @@ version = "0.0.1"
 [dependencies]
 error-chain = "0.12.0"
 fastcgi = "1.0.0"
+log = "0.4.6"
 mysql = "14.1.1"
 rand = "0.5.5"
 sha1 = { version = "0.6.0", features = ["std"] }
+simplelog = "0.5.3"
 
 [workspace]
 members = [
diff --git a/license-generator/src/database.rs b/license-generator/src/database.rs
index 28673c4..94e925f 100644
--- a/license-generator/src/database.rs
+++ b/license-generator/src/database.rs
@@ -4,7 +4,7 @@ use mysql;
 
 use errors::*;
 
-fn get_database_connection() -> Result<mysql::PooledConn> {
+pub fn get_database_connection() -> Result<mysql::PooledConn> {
     let connection_url = env::var("DATABASE_URL")?;
     let pool = mysql::Pool::new_manual(10, 50, connection_url)?;
     let cx = pool.get_conn()?;
diff --git a/license-generator/src/errors.rs b/license-generator/src/errors.rs
index 29f25ca..0a28341 100644
--- a/license-generator/src/errors.rs
+++ b/license-generator/src/errors.rs
@@ -1,9 +1,12 @@
+use log;
 use mysql;
 
 error_chain! {
     foreign_links {
         EnvVar(::std::env::VarError);
+        Io(::std::io::Error);
 
+        Log(log::SetLoggerError);
         MySql(mysql::error::Error);
     }
 }
diff --git a/license-generator/src/lib.rs b/license-generator/src/lib.rs
index e129d17..4dd726d 100644
--- a/license-generator/src/lib.rs
+++ b/license-generator/src/lib.rs
@@ -1,10 +1,11 @@
 #[macro_use]
 extern crate error_chain;
+extern crate log;
 extern crate mysql;
 extern crate rand;
 extern crate sha1;
 
 
-mod database;
-mod errors;
+pub mod database;
+pub mod errors;
 mod purchaser;
diff --git a/license-generator/src/main.rs b/license-generator/src/main.rs
index fab9eb1..32fdc3b 100644
--- a/license-generator/src/main.rs
+++ b/license-generator/src/main.rs
@@ -1,8 +1,41 @@
 extern crate fastcgi;
 
+#[macro_use]
+extern crate log;
+extern crate mysql;
+extern crate simplelog;
+
+extern crate license_generator;
+
+use std::env;
+use std::fs::OpenOptions;
 use std::io::{Read, Write};
 
-fn main() {
+use simplelog::{Config, LevelFilter, WriteLogger};
+
+use license_generator::database;
+use license_generator::errors::*;
+
+fn main() -> Result<()> {
+    let log_file_path = env::var("LOG_FILE")?;
+
+    let log_file = OpenOptions::new()
+        .append(true)
+        .create(true)
+        .open(log_file_path)?;
+
+    WriteLogger::init(LevelFilter::Info, Config::default(), log_file)?;
+
+    let cx = match database::get_database_connection()
+        .chain_err(|| "failed to create a database connection")
+    {
+        Ok(cx) => cx,
+        Err(e) => {
+            error!("{}", e);
+            return Err(e);
+        },
+    };
+
     fastcgi::run(|mut req| {
         write!(&mut req.stdout(), "Content-Type: text/plain\n\nHello, world!")
             .unwrap_or(());
@@ -21,4 +54,6 @@ fn main() {
         write!(&mut req.stdout(), "\n\nstdin: {}\n", stdin)
             .unwrap_or(());
     });
+
+    Ok(())
 }