Added jMustache as templating engine (#62)

* Added jMustache as templating engine

pom.xml

@@ -349,6 +349,13 @@
             <version>8.0.0.Final</version>
         </dependency>
 
+        <!-- https://mvnrepository.com/artifact/com.samskivert/jmustache -->
+        <dependency>
+            <groupId>com.samskivert</groupId>
+            <artifactId>jmustache</artifactId>
+            <version>1.15</version>
+        </dependency>
+
     </dependencies>
 
     <dependencyManagement>

src/main/java/com/github/estuaryoss/agent/utils/TemplateGluer.java

@@ -1,23 +1,17 @@
 package com.github.estuaryoss.agent.utils;
 
+import com.samskivert.mustache.Mustache;
+import com.samskivert.mustache.Template;
+
 import java.util.Map;
 
 public class TemplateGluer {
-    private static final int RUN_DEPTH = 5;
 
     public static String glue(String template, Map<String, String> swapValuesMap) {
         if (swapValuesMap == null || template == null) return template;
 
-        for (int i = 0; i < RUN_DEPTH; i++) {
-            for (Map.Entry<String, String> entry : swapValuesMap.entrySet()) {
-                String key = entry.getKey();
-                String value = entry.getValue();
-
-                template = template.replace(String.format("{%s}", key), value);
-                template = template.replace(String.format("{ %s }", key), value);
-            }
-        }
+        Template jMustacheTemplate = Mustache.compiler().compile(template);
 
-        return template;
+        return jMustacheTemplate.execute(swapValuesMap);
     }
 }

src/test/java/com/github/estuaryoss/agent/api/EnvApiControllerTest.java

@@ -217,7 +217,7 @@ public void whenSettingExternalEnvVarsFromFileAndItsASystemOneThenItDoesntGetOve
             strings = {
                     "FOO1;BARx;BARx",
                     "FOO3;BAR3;BAR3",
-                    "FOO4;{FOO1}/{FOO3};BARx/BAR3"
+                    "FOO4;{{FOO1}}/{{FOO3}};BARx/BAR3"
             }
     )
     @Order(3)

src/test/java/com/github/estuaryoss/agent/unit/AppEnvironmentTest.java

@@ -74,7 +74,7 @@ public void whenSettingEnvVarWhichHasReferenceToAnotherEnvVar_TheSecondOneIsInte
         String envVarName1 = "FOO1";
         String envVarName1Value = "/FOO1/BAR1";
         String envVarName2 = "FOO2";
-        String envVarName2Value = "{FOO1}/BAR2";
+        String envVarName2Value = "{{FOO1}}/BAR2";
         Map<String, String> envVarsToBeSet = new LinkedHashMap<>();
         envVarsToBeSet.put(envVarName1, envVarName1Value);
         envVarsToBeSet.put(envVarName2, envVarName2Value);

src/test/java/com/github/estuaryoss/agent/unit/TemplateGluerTest.java

@@ -13,9 +13,9 @@ public class TemplateGluerTest {
     @ParameterizedTest
     @ValueSource(
             strings = {
-                    "{FOO1}/A;FOO1;B;B/A",
+                    "{{FOO1}}/A;FOO1;B;B/A",
                     "A;A;A;A",
-                    "A/{FOO1};FOO1;B;A/B",
+                    "A/{{FOO1}};FOO1;B;A/B",
             }
     )
     public void whenSwapping_ThenProfit(String templateInVarNameInVarValueExpectedOut) {