embed migrations, create migration tool, make nix build work

backend/Cargo.lock

@@ -485,6 +485,16 @@ dependencies = [
  "syn 1.0.40",
 ]
 
+[[package]]
+name = "diesel_migrations"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf3cde8413353dc7f5d72fa8ce0b99a560a359d2c5ef1e5817ca731cd9008f4c"
+dependencies = [
+ "migrations_internals",
+ "migrations_macros",
+]
+
 [[package]]
 name = "digest"
 version = "0.8.1"
@@ -1044,6 +1054,7 @@ dependencies = [
  "chrono",
  "color-eyre",
  "diesel",
+ "diesel_migrations",
  "futures-io",
  "hex",
  "log 0.4.11",
@@ -1068,6 +1079,27 @@ dependencies = [
  "url 2.1.1",
 ]
 
+[[package]]
+name = "migrations_internals"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b4fc84e4af020b837029e017966f86a1c2d5e83e64b589963d5047525995860"
+dependencies = [
+ "diesel",
+]
+
+[[package]]
+name = "migrations_macros"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9753f12909fd8d923f75ae5c3258cae1ed3c8ec052e1b38c93c21a6d157f789c"
+dependencies = [
+ "migrations_internals",
+ "proc-macro2 1.0.21",
+ "quote 1.0.7",
+ "syn 1.0.40",
+]
+
 [[package]]
 name = "mime"
 version = "0.2.6"

backend/Cargo.toml

@@ -10,6 +10,7 @@ edition = "2018"
 askama_rocket = "0.10"
 chrono = { version = "0.4", features = ["serde"] }
 color-eyre = "0.5"
+diesel_migrations = "1"
 futures-io = "0.3"
 hex = "0.4"
 log = "0.4"

backend/src/bin/migrate_database.rs

@@ -0,0 +1,34 @@
+#[macro_use]
+extern crate diesel_migrations;
+#[macro_use]
+extern crate tracing;
+
+use color_eyre::eyre::{eyre, Result};
+use diesel::prelude::*;
+use mi::APPLICATION_NAME;
+use std::env;
+
+diesel_migrations::embed_migrations!("./migrations");
+
+pub fn establish_connection() -> Result<SqliteConnection> {
+    let database_url = env::var("DATABASE_URL").unwrap_or("./mi.db".to_string());
+    SqliteConnection::establish(&database_url)
+        .map_err(|why| eyre!("can't connect to {}: {}", database_url, why))
+}
+
+fn main() -> Result<()> {
+    color_eyre::install()?;
+    tracing_subscriber::fmt::init();
+
+    info!("{} migrator starting up", APPLICATION_NAME);
+
+    info!("running migrations");
+    let connection = establish_connection()?;
+    embedded_migrations::run_with_output(&connection, &mut std::io::stdout()).map_err(|why| {
+        error!("migration error: {}", why);
+        why
+    })?;
+    info!("migrations succeeded");
+
+    Ok(())
+}

default.nix

@@ -1,30 +1,46 @@
 { sources ? import ./nix/sources.nix, pkgs ? import sources.nixpkgs { } }:
 with pkgs;
 let
-  backend = pkgs.callPackage ./backend { inherit sources pkgs; };
+  backend = callPackage ./backend { inherit sources pkgs; };
-  frontend = pkgs.callPackage ./sina { inherit sources pkgs; };
+  frontend = callPackage ./sina { inherit sources pkgs; };
-  gruvbox = pkgs.callPackage sources.gruvbox-css { };
+  gruvbox = callPackage sources.gruvbox-css { };
-in stdenv.mkDerivation {
-  pname = "mi";
-  version = "${backend.version}";
-  phases = "installPhase";
 
-  installPhase = ''
+  composite = stdenv.mkDerivation {
-    # service binary
+    pname = "mi";
-    mkdir -p $out/bin
+    version = "${backend.version}";
+    phases = "installPhase";
 
-    for file in ${backend}/bin/*; do
+    installPhase = ''
-      ln -s ${backend}/bin/$(${coreutils}/bin/basename $file) $out/bin/$(${coreutils}/bin/basename $file)
+      # service binary
-    done
+      mkdir -p $out/bin
 
-    # frontend JS
+      for file in ${backend}/bin/*; do
-    mkdir -p $out/public/js
+        ln -s ${backend}/bin/$(basename $file) $out/bin/$(basename $file)
-    ln -s ${frontend}/Main.js $out/public/js/elm.js
+      done
 
-    # static files
+      # static files
-    cp -vrf ${./static}/* $out/public
+      mkdir -p $out/public/
+      cp -vrf ${./static}/* $out/public
 
-    # migrations
+      # frontend JS
-    ln -s ${./backend/migrations} $out/migrations
+      rm $out/public/elm.js
+      ln -s ${frontend}/Main.min.js $out/public/elm.js
+    '';
+  };
+
+  wrapper = writeScriptBin "mi-backend" ''
+    #!${pkgs.stdenv.shell}
+    set -e
+    set -x
+
+    export RUST_LOG=info
+    export DATABASE_URL=./mi.db
+    export ROCKET_DATABASES='{ main_data = { url = "./mi.db" } }';
+    ${composite}/bin/migrate_database
+    export ROCKET_ASSET_PATH=${composite}/public
+    exec ${composite}/bin/mi
   '';
+in symlinkJoin {
+  name = "mi";
+  paths = [ wrapper composite ];
 }

shell.nix

@@ -34,6 +34,7 @@ in pkgs.mkShell rec {
   GRUVBOX_CSS = "${gruvbox}/gruvbox.css";
 
   DATABASE_URL = "./mi.db";
+  MIGRATION_PATH = "./migrations";
   ROCKET_DATABASES = ''{ main_data = { url = "${DATABASE_URL}" } }'';
   RUST_LOG = "info";