From fbcd1715e99ed3b6e76fcc213fb379ffe2d378d7 Mon Sep 17 00:00:00 2001
From: Yago Iglesias <yagoiglesias7@gmail.com>
Date: Sat, 2 Sep 2023 00:02:28 +0200
Subject: [PATCH] feat(config): Allow the use of environment variables in the
 configuration file

I also added a way of deserilizing numbers
---
 Cargo.lock            | 12 ++++++++++
 Cargo.toml            |  1 +
 spec.yml              | 51 +++++++++++++++++++++++++++++++++++++++++++
 src/configurations.rs | 14 +++++++++---
 4 files changed, 75 insertions(+), 3 deletions(-)
 create mode 100644 spec.yml

diff --git a/Cargo.lock b/Cargo.lock
index c8fc1b4..a45df25 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1658,6 +1658,17 @@ dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "serde-aux"
+version = "4.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3dfe1b7eb6f9dcf011bd6fad169cdeaae75eda0d61b1a99a3f015b41b0cae39"
+dependencies = [
+ "chrono",
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "serde_derive"
 version = "1.0.188"
@@ -2517,6 +2528,7 @@ dependencies = [
  "reqwest",
  "secrecy",
  "serde",
+ "serde-aux",
  "sqlx",
  "tokio",
  "tracing",
diff --git a/Cargo.toml b/Cargo.toml
index 6157017..b2f25e9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -27,6 +27,7 @@ tracing-log = "0.1"
 once_cell = "1"
 secrecy = { version = "0.8", features = ["serde"] }
 tracing-actix-web = "0.7"
+serde-aux = "4"
 
 [dev-dependencies]
 reqwest = { version = "0.11", features = ["json"] }
diff --git a/spec.yml b/spec.yml
new file mode 100644
index 0000000..47704db
--- /dev/null
+++ b/spec.yml
@@ -0,0 +1,51 @@
+name: zero2prod
+# Check https://www.digitalocean.com/docs/app-platform/#regional-availability
+# for a list of all the available options.
+# You can get region slugs from
+# https://www.digitalocean.com/docs/platform/availability-matrix/
+# They must specified lowercased.
+# `fra` stands for Frankfurt (Germany - EU)
+region: fra
+services:
+  - name: zero2prod
+    # Relative to the repository root
+    dockerfile_path: Dockerfile
+    source_dir: .
+    github:
+      # Depending on when you created the repository,
+      # the default branch on GitHub might have been named `master`
+      branch: master
+      # Deploy a new version on every commit to `main`!
+      # Continuous Deployment, here we come!
+      deploy_on_push: true
+      # !!! Fill in with your details
+      # e.g. LukeMathWalker/zero-to-production
+      repo: Yag000/zero2prod
+    # Active probe used by DigitalOcean's to ensure our application is healthy
+    health_check:
+      # The path to our health check endpoint!
+      # It turned out to be useful in the end!
+      http_path: /health_check
+      # The port the application will be listening on for incoming requests
+      # It should match what we specified in our configuration/production.yaml file!
+    http_port: 8000
+    # For production workloads we'd go for at least two!
+    # But let's try to keep the bill under control for now...
+    instance_count: 1
+    instance_size_slug: basic-xxs
+    # All incoming requests should be routed to our app
+    routes:
+      - path: /
+
+databases:
+  # PG = Postgres
+  - engine: PG
+    # Database name
+    name:
+      newsletter
+      # Again, let's keep the bill lean
+    num_nodes: 1
+    size:
+      db-s-dev-database
+      # Postgres version - using the latest here
+    version: "12"
diff --git a/src/configurations.rs b/src/configurations.rs
index 2a150e6..ada0459 100644
--- a/src/configurations.rs
+++ b/src/configurations.rs
@@ -1,6 +1,6 @@
 use config::Config;
 use secrecy::{ExposeSecret, Secret};
-
+use serde_aux::field_attributes::deserialize_number_from_string;
 #[derive(serde::Deserialize)]
 pub struct Settings {
     pub database: DatabaseSettings,
@@ -9,15 +9,17 @@ pub struct Settings {
 
 #[derive(serde::Deserialize)]
 pub struct DatabaseSettings {
+    #[serde(deserialize_with = "deserialize_number_from_string")]
+    pub port: u16,
     pub username: String,
     pub password: Secret<String>,
-    pub port: u16,
     pub host: String,
     pub database_name: String,
 }
 
 #[derive(serde::Deserialize)]
 pub struct ApplicationSettings {
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub port: u16,
     pub host: String,
 }
@@ -53,11 +55,17 @@ pub fn get_configuration() -> Result<Settings, config::ConfigError> {
         .unwrap_or_else(|_| "local".into())
         .try_into()
         .expect("Failed to parse APP_ENVIRONMENT.");
+    let environment_filename = format!("{}.yaml", environment.as_str());
 
     let settings = Config::builder()
         .add_source(config::File::from(configuration_directory.join("base")).required(true))
         .add_source(
-            config::File::from(configuration_directory.join(environment.as_str())).required(true),
+            config::File::from(configuration_directory.join(environment_filename)).required(true),
+        )
+        .add_source(
+            config::Environment::with_prefix("APP")
+                .prefix_separator("_")
+                .separator("__"),
         );
 
     match settings.build() {