From 72af2f322ea12ebc7a28ef2b88c1450e1fe6f588 Mon Sep 17 00:00:00 2001
From: Mike Bierlee <m.bierlee@lostmoment.com>
Date: Wed, 28 Sep 2022 23:54:38 +0300
Subject: [PATCH] Add env var substitution test for JSON

---
 source/mirage/json.d  | 15 +++++++++++++++
 testfiles/server.json |  7 +++++++
 2 files changed, 22 insertions(+)
 create mode 100644 testfiles/server.json

diff --git a/source/mirage/json.d b/source/mirage/json.d
index c8505c9..df4b937 100644
--- a/source/mirage/json.d
+++ b/source/mirage/json.d
@@ -130,6 +130,8 @@ ConfigDictionary loadJsonConfig(const string filePath) {
 }
 
 version (unittest) {
+    import std.process : environment;
+
     @("Parse JSON")
     unittest {
         JSONValue serverJson = ["hostname": "hosty.com", "port": "1234"];
@@ -193,4 +195,17 @@ version (unittest) {
         assert(config.get("age") == "8728");
         assert(config.get("taxNumber") == null);
     }
+
+    @("Substitute env vars in JSON")
+    unittest {
+        environment["MIRAGE_TEST_APP_NAME"] = "Unittest";
+        environment["MIRAGE_TEST_HOSTNAME"] = "wonkeyhost";
+        environment.remove("MIRAGE_TEST_PORT");
+
+        auto config = loadJsonConfig("testfiles/server.json");
+
+        assert(config.get("server.host") == "wonkeyhost");
+        assert(config.get("server.port") == "8118");
+        assert(config.get("app") == "Unittest server - built with love");
+    }
 }
diff --git a/testfiles/server.json b/testfiles/server.json
new file mode 100644
index 0000000..c5ae2b8
--- /dev/null
+++ b/testfiles/server.json
@@ -0,0 +1,7 @@
+{
+  "server": {
+    "host": "$MIRAGE_TEST_HOSTNAME",
+    "port": "${MIRAGE_TEST_PORT:8118}"
+  },
+  "app": "${MIRAGE_TEST_APP_NAME} server - built with love"
+}