From bd9f5a78196bea7c97b6b4580c726f4218867320 Mon Sep 17 00:00:00 2001
From: Nick Bland <nick.bland@nickbland.dev>
Date: Thu, 31 Aug 2023 22:15:34 +1000
Subject: [PATCH] Re-Arrange structure. Add unit testing.

---
 Cargo.lock            | 467 +++++++++++++++++++++++++++++++++++++++++-
 Cargo.toml            |  12 +-
 src/lib.rs            |  17 ++
 src/main.rs           |  18 +-
 tests/health_check.rs |  30 +++
 5 files changed, 526 insertions(+), 18 deletions(-)
 create mode 100644 src/lib.rs
 create mode 100644 tests/health_check.rs

diff --git a/Cargo.lock b/Cargo.lock
index b12ff43..aa9af37 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -103,7 +103,7 @@ dependencies = [
  "futures-core",
  "futures-util",
  "mio",
- "socket2",
+ "socket2 0.5.3",
  "tokio",
  "tracing",
 ]
@@ -164,7 +164,7 @@ dependencies = [
  "serde_json",
  "serde_urlencoded",
  "smallvec",
- "socket2",
+ "socket2 0.5.3",
  "time",
  "url",
 ]
@@ -301,6 +301,12 @@ dependencies = [
  "alloc-stdlib",
 ]
 
+[[package]]
+name = "bumpalo"
+version = "3.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3e2c3daef883ecc1b5d58c15adae93470a91d425f3532ba1695849656af3fc1"
+
 [[package]]
 name = "bytes"
 version = "1.4.0"
@@ -349,6 +355,22 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "core-foundation"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "194a7a9e6de53fa55116934067c844d9d749312f75c6f6d0980e8c252f8c2146"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
+[[package]]
+name = "core-foundation-sys"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
+
 [[package]]
 name = "cpufeatures"
 version = "0.2.9"
@@ -415,6 +437,33 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "errno"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "136526188508e25c6fef639d7927dfb3e0e3084488bf202267829cf7fc23dbdd"
+dependencies = [
+ "errno-dragonfly",
+ "libc",
+ "windows-sys",
+]
+
+[[package]]
+name = "errno-dragonfly"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa68f1b12764fab894d2755d2518754e71b4fd80ecfb822714a1206c2aab39bf"
+dependencies = [
+ "cc",
+ "libc",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6999dc1837253364c2ebb0704ba97994bd874e8f195d665c50b7548f6ea92764"
+
 [[package]]
 name = "flate2"
 version = "1.0.27"
@@ -431,6 +480,21 @@ version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
+[[package]]
+name = "foreign-types"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
+dependencies = [
+ "foreign-types-shared",
+]
+
+[[package]]
+name = "foreign-types-shared"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
+
 [[package]]
 name = "form_urlencoded"
 version = "1.2.0"
@@ -440,6 +504,15 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures-channel"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "955518d47e09b25bbebc7a18df10b81f0c766eaf4c4f1cccef2fca5f2a4fb5f2"
+dependencies = [
+ "futures-core",
+]
+
 [[package]]
 name = "futures-core"
 version = "0.3.28"
@@ -539,6 +612,17 @@ dependencies = [
  "itoa",
 ]
 
+[[package]]
+name = "http-body"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d5f38f16d184e36f2408a55281cd658ecbd3ca05cce6d6510a176eca393e26d1"
+dependencies = [
+ "bytes",
+ "http",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "httparse"
 version = "1.8.0"
@@ -551,6 +635,43 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df3b46402a9d5adb4c86a0cf463f42e19994e3ee891101b1841f30a545cb49a9"
 
+[[package]]
+name = "hyper"
+version = "0.14.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ffb1cfd654a8219eaef89881fdb3bb3b1cdc5fa75ded05d6933b2b382e395468"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-core",
+ "futures-util",
+ "h2",
+ "http",
+ "http-body",
+ "httparse",
+ "httpdate",
+ "itoa",
+ "pin-project-lite",
+ "socket2 0.4.9",
+ "tokio",
+ "tower-service",
+ "tracing",
+ "want",
+]
+
+[[package]]
+name = "hyper-tls"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d6183ddfa99b85da61a140bea0efc93fdf56ceaa041b37d553518030827f9905"
+dependencies = [
+ "bytes",
+ "hyper",
+ "native-tls",
+ "tokio",
+ "tokio-native-tls",
+]
+
 [[package]]
 name = "idna"
 version = "0.4.0"
@@ -571,6 +692,12 @@ dependencies = [
  "hashbrown",
 ]
 
+[[package]]
+name = "ipnet"
+version = "2.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28b29a3cd74f0f4598934efe3aeba42bae0eb4680554128851ebbecb02af14e6"
+
 [[package]]
 name = "itoa"
 version = "1.0.9"
@@ -586,18 +713,39 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "js-sys"
+version = "0.3.64"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5f195fe497f702db0f318b07fdd68edb16955aed830df8363d837542f8f935a"
+dependencies = [
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "language-tags"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d4345964bb142484797b161f473a503a434de77149dd8c7427788c6e13379388"
 
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
 [[package]]
 name = "libc"
 version = "0.2.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b4668fb0ea861c1df094127ac5f1da3409a82116a4ba74fca2e58ef927159bb3"
 
+[[package]]
+name = "linux-raw-sys"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57bcfdad1b858c2db7c38303a6d2ad4dfaf5eb53dfeb0910128b2c26d6158503"
+
 [[package]]
 name = "local-channel"
 version = "0.1.3"
@@ -637,6 +785,7 @@ name = "mail_app"
 version = "0.1.0"
 dependencies = [
  "actix-web",
+ "reqwest",
  "tokio",
 ]
 
@@ -673,6 +822,24 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "native-tls"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07226173c32f2926027b63cce4bcd8076c3552846cbe7925f3aaffeac0a3b92e"
+dependencies = [
+ "lazy_static",
+ "libc",
+ "log",
+ "openssl",
+ "openssl-probe",
+ "openssl-sys",
+ "schannel",
+ "security-framework",
+ "security-framework-sys",
+ "tempfile",
+]
+
 [[package]]
 name = "num_cpus"
 version = "1.16.0"
@@ -698,6 +865,50 @@ version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd8b5dd2ae5ed71462c540258bedcb51965123ad7e7ccf4b9a8cafaa4a63576d"
 
+[[package]]
+name = "openssl"
+version = "0.10.57"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bac25ee399abb46215765b1cb35bc0212377e58a061560d8b29b024fd0430e7c"
+dependencies = [
+ "bitflags 2.4.0",
+ "cfg-if",
+ "foreign-types",
+ "libc",
+ "once_cell",
+ "openssl-macros",
+ "openssl-sys",
+]
+
+[[package]]
+name = "openssl-macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.29",
+]
+
+[[package]]
+name = "openssl-probe"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ff011a302c396a5197692431fc1948019154afc178baf7d8e37367442a4601cf"
+
+[[package]]
+name = "openssl-sys"
+version = "0.9.92"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db7e971c2c2bba161b2d2fdf37080177eff520b3bc044787c7f1f5f9e78d869b"
+dependencies = [
+ "cc",
+ "libc",
+ "pkg-config",
+ "vcpkg",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.12.1"
@@ -843,6 +1054,43 @@ version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dbb5fb1acd8a1a18b3dd5be62d25485eb770e05afb408a9627d14d451bae12da"
 
+[[package]]
+name = "reqwest"
+version = "0.11.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3e9ad3fe7488d7e34558a2033d45a0c90b72d97b4f80705666fea71472e2e6a1"
+dependencies = [
+ "base64",
+ "bytes",
+ "encoding_rs",
+ "futures-core",
+ "futures-util",
+ "h2",
+ "http",
+ "http-body",
+ "hyper",
+ "hyper-tls",
+ "ipnet",
+ "js-sys",
+ "log",
+ "mime",
+ "native-tls",
+ "once_cell",
+ "percent-encoding",
+ "pin-project-lite",
+ "serde",
+ "serde_json",
+ "serde_urlencoded",
+ "tokio",
+ "tokio-native-tls",
+ "tower-service",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "winreg",
+]
+
 [[package]]
 name = "rustc-demangle"
 version = "0.1.23"
@@ -858,18 +1106,63 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustix"
+version = "0.38.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ed6248e1caa625eb708e266e06159f135e8c26f2bb7ceb72dc4b2766d0340964"
+dependencies = [
+ "bitflags 2.4.0",
+ "errno",
+ "libc",
+ "linux-raw-sys",
+ "windows-sys",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ad4cc8da4ef723ed60bced201181d83791ad433213d8c24efffda1eec85d741"
 
+[[package]]
+name = "schannel"
+version = "0.1.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c3733bf4cf7ea0880754e19cb5a462007c4a8c1914bff372ccc95b464f1df88"
+dependencies = [
+ "windows-sys",
+]
+
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "security-framework"
+version = "2.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05b64fb303737d99b81884b2c63433e9ae28abebe5eb5045dcdd175dc2ecf4de"
+dependencies = [
+ "bitflags 1.3.2",
+ "core-foundation",
+ "core-foundation-sys",
+ "libc",
+ "security-framework-sys",
+]
+
+[[package]]
+name = "security-framework-sys"
+version = "2.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e932934257d3b408ed8f30db49d85ea163bfe74961f017f405b025af298f0c7a"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
 [[package]]
 name = "semver"
 version = "1.0.18"
@@ -954,6 +1247,16 @@ version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "62bb4feee49fdd9f707ef802e22365a35de4b7b299de4763d44bfea899442ff9"
 
+[[package]]
+name = "socket2"
+version = "0.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "64a4a911eed85daf18834cfaa86a79b7d266ff93ff5ba14005426219480ed662"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "socket2"
 version = "0.5.3"
@@ -986,6 +1289,19 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "tempfile"
+version = "3.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb94d2f3cc536af71caac6b6fcebf65860b347e7ce0cc9ebe8f70d3e521054ef"
+dependencies = [
+ "cfg-if",
+ "fastrand",
+ "redox_syscall",
+ "rustix",
+ "windows-sys",
+]
+
 [[package]]
 name = "time"
 version = "0.3.28"
@@ -1043,7 +1359,7 @@ dependencies = [
  "parking_lot",
  "pin-project-lite",
  "signal-hook-registry",
- "socket2",
+ "socket2 0.5.3",
  "tokio-macros",
  "windows-sys",
 ]
@@ -1059,6 +1375,16 @@ dependencies = [
  "syn 2.0.29",
 ]
 
+[[package]]
+name = "tokio-native-tls"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbae76ab933c85776efabc971569dd6119c580d8f5d448769dec1764bf796ef2"
+dependencies = [
+ "native-tls",
+ "tokio",
+]
+
 [[package]]
 name = "tokio-util"
 version = "0.7.8"
@@ -1073,6 +1399,12 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "tower-service"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6bc1c9ce2b5135ac7f93c72918fc37feb872bdc6a5533a8b85eb4b86bfdae52"
+
 [[package]]
 name = "tracing"
 version = "0.1.37"
@@ -1094,6 +1426,12 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "try-lock"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3528ecfd12c466c6f163363caf2d02a71161dd5e1cc6ae7b34207ea2d42d81ed"
+
 [[package]]
 name = "typenum"
 version = "1.16.0"
@@ -1132,18 +1470,131 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "vcpkg"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
+
 [[package]]
 name = "version_check"
 version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
+[[package]]
+name = "want"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfa7760aed19e106de2c7c0b581b509f2f25d3dacaf737cb82ac61bc6d760b0e"
+dependencies = [
+ "try-lock",
+]
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "wasm-bindgen"
+version = "0.2.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7706a72ab36d8cb1f80ffbf0e071533974a60d0a308d01a5d0375bf60499a342"
+dependencies = [
+ "cfg-if",
+ "wasm-bindgen-macro",
+]
+
+[[package]]
+name = "wasm-bindgen-backend"
+version = "0.2.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5ef2b6d3c510e9625e5fe6f509ab07d66a760f0885d858736483c32ed7809abd"
+dependencies = [
+ "bumpalo",
+ "log",
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.29",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-futures"
+version = "0.4.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c02dbc21516f9f1f04f187958890d7e6026df8d16540b7ad9492bc34a67cea03"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
+[[package]]
+name = "wasm-bindgen-macro"
+version = "0.2.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dee495e55982a3bd48105a7b947fd2a9b4a8ae3010041b9e0faab3f9cd028f1d"
+dependencies = [
+ "quote",
+ "wasm-bindgen-macro-support",
+]
+
+[[package]]
+name = "wasm-bindgen-macro-support"
+version = "0.2.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "54681b18a46765f095758388f2d0cf16eb8d4169b639ab575a8f5693af210c7b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.29",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-shared"
+version = "0.2.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca6ad05a4870b2bf5fe995117d3728437bd27d7cd5f06f13c17443ef369775a1"
+
+[[package]]
+name = "web-sys"
+version = "0.3.64"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b85cbef8c220a6abc02aefd892dfc0fc23afb1c6a426316ec33253a3877249b"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
 [[package]]
 name = "windows-sys"
 version = "0.48.0"
@@ -1210,6 +1661,16 @@ version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
 
+[[package]]
+name = "winreg"
+version = "0.50.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "524e57b2c537c0f9b1e69f1965311ec12182b4122e45035b1508cd24d2adadb1"
+dependencies = [
+ "cfg-if",
+ "windows-sys",
+]
+
 [[package]]
 name = "zstd"
 version = "0.12.4"
diff --git a/Cargo.toml b/Cargo.toml
index 772aa71..831a25a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,8 +3,16 @@ name = "mail_app"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[lib]
+path = "src/lib.rs"
+
+[[bin]]
+path = "src/main.rs"
+name = "mail_app"
 
 [dependencies]
 actix-web = "4"
-tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
\ No newline at end of file
+tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
+
+[dev-dependencies]
+reqwest = "0.11"
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..49c39e9
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,17 @@
+use actix_web::{web, App, HttpResponse, HttpServer};
+use actix_web::dev::Server;
+use std::net::TcpListener;
+
+async fn health_check() -> HttpResponse {
+    HttpResponse::Ok().finish()
+}
+
+pub fn run(listener: TcpListener) -> Result<Server, std::io::Error> {
+    let server = HttpServer::new(|| {
+        App::new()
+            .route("/health_check", web::get().to(health_check))
+        })
+        .listen(listener)?
+        .run();
+    Ok(server)
+}
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index a9fbda9..291609e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,18 +1,10 @@
-use actix_web::{web, App, HttpRequest, HttpServer, Responder};
+use mail_app::run;
 
-async fn greet(req: HttpRequest) -> impl Responder {
-    let name = req.match_info().get("name").unwrap_or("World");
-    format!("Hello {}!", &name)
-}
+use std::net::TcpListener;
 
 #[tokio::main]
 async fn main() -> Result<(), std::io::Error> {
-    HttpServer::new(|| {
-        App::new()
-            .route("/", web::get().to(greet))
-            .route("/{name}", web::get().to(greet))
-    })
-    .bind("127.0.0.1:8000")?
-    .run()
-    .await
+    let listener = TcpListener::bind("127.0.0.1:8000")
+        .expect("Failed to bind to port 8000");
+    run(listener)?.await
 }
diff --git a/tests/health_check.rs b/tests/health_check.rs
new file mode 100644
index 0000000..ce6b28c
--- /dev/null
+++ b/tests/health_check.rs
@@ -0,0 +1,30 @@
+use std::net::TcpListener;
+
+#[tokio::test]
+async fn health_check_works() {
+    // Arrange
+    let address = spawn_app();
+    let client = reqwest::Client::new();
+
+    // Act
+    let response = client
+        .get(&format!("{}/health_check", &address))
+        .send()
+        .await
+        .expect("Failed to execute request");
+
+    // Assert
+    assert!(response.status().is_success());
+    assert_eq!(Some(0), response.content_length());
+}
+
+fn spawn_app() -> String {
+    let listener = TcpListener::bind("127.0.0.1:0")
+        .expect("Failed to bind to random port.");
+    let port = listener.local_addr().unwrap().port();
+    let server = mail_app::run(listener).expect("Failed to bind address");
+    // Launch in background
+    let _spawn = tokio::spawn(server);
+
+    format!("http://127.0.0.1:{}", port)
+}