Feature/template resolution by external service

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#   http://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.4/apache-maven-3.8.4-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar

core/core-services-impl/src/main/java/com/sflpro/notifier/services/notification/impl/email/DefaultEmailSenderProvider.java

@@ -44,6 +44,6 @@ public Optional<TemplatedEmailSender> lookupTemplatedEmailSenderFor(final String
     }
 
     private static void assertValidProviderTypeArgument(final String providerType) {
-        Assert.hasText(providerType, "Null or empty text was passed as ana rgument for parameter 'providerType'.");
+        Assert.hasText(providerType, "Null or empty text was passed as an argument for parameter 'providerType'.");
     }
 }

core/core-services-impl/src/main/java/com/sflpro/notifier/services/template/impl/TemplatingConfigurationImpl.java

@@ -21,14 +21,17 @@ public class TemplatingConfigurationImpl implements TemplatingConfiguration {
 
     private String templatesPath = "/";
     private String templateExtension = ".ftl";
+    private Boolean externalUrl = false;
 
     private final ResourceLoader resourceLoader = new DefaultResourceLoader();
 
     TemplatingConfigurationImpl(
             @Value("${notifier.templates.path}") final String templatesPath,
-            @Value("${notifier.templates.extension:.ftl}") final String templateExtension) {
+            @Value("${notifier.templates.extension:.ftl}") final String templateExtension,
+            @Value("${notifier.templates.externalUrl:false}") final Boolean externalUrl) {
         this.templatesPath = templatesPath;
         this.templateExtension = templateExtension;
+        this.externalUrl = externalUrl;
     }
 
 
@@ -38,9 +41,14 @@ public Configuration getFreemarkerConfiguration(final boolean localizedLookupEna
             @Override
             protected URL getURL(final String resourceName) {
                 try {
-                    final Resource resource = getResource(resourceName);
-                    return resource.exists() ? resource.getURL() : null;
-                } catch (final IOException ex) {
+                    final String fullPath = getFullPath(resourceName);
+                    if (externalUrl) {
+                        return new URL(fullPath);
+                    } else {
+                        final Resource resource = getResource(fullPath);
+                        return resource.exists() ? resource.getURL() : null;
+                    }
+                } catch (IOException ex) {
                     throw new TemplateLookupFailedException(resourceName, templatesPath, ex);
                 }
             }
@@ -53,15 +61,18 @@ protected URL getURL(final String resourceName) {
         return cfg;
     }
 
-    private Resource getResource(final String resourceName) throws IOException {
+    private Resource getResource(final String fullPath) throws IOException {
+        return resourceLoader.getResource(fullPath);
+    }
+
+    private String getFullPath(final String resourceName) {
         if (!resourceName.endsWith(templateExtension)) {
-            return resourceLoader.getResource(templatesPath + "/" + resourceName + templateExtension);
+            return templatesPath + "/" + resourceName + templateExtension;
         } else {
-            return resourceLoader.getResource(templatesPath + "/" + resourceName);
+            return templatesPath + "/" + resourceName;
         }
     }
 
-
     private static final class TemplateLookupFailedException extends RuntimeException {
 
         private static String message(final String resourceName, final String templatesPath) {

core/core-services-impl/src/main/resources/com/sflpro/notifier/services.properties

@@ -6,5 +6,6 @@ notification.push.application.arn.operator.android=customer_ios_arn
 
 # Freemarker
 notifier.templates.path=
+notifier.templates.externalUrl=
 
 flyway.locations=classpath:db/migration/{vendor}

core/core-services-impl/src/test/java/com/sflpro/notifier/services/template/impl/TemplatingConfigurationImplTest.java

@@ -27,11 +27,12 @@ public void testGetFreemarkerConfiguration() throws IOException {
             final String prefix = "dummy";
             final String extension = ".ftl";
             tempFile = File.createTempFile(prefix, extension);
-            localizedTempFile = new File(tempFile.getAbsolutePath().replace(extension, "_" + locale.toString() + extension));
+            localizedTempFile = new File(tempFile.getAbsolutePath().replace(extension, "_" + locale + extension));
             localizedTempFile.createNewFile();
             final TemplatingConfiguration configuration = new TemplatingConfigurationImpl(
                     "file:///" + tempFile.getParent(),
-                    extension
+                    extension,
+                    false
             );
             assertThat(configuration.getFreemarkerConfiguration(true).getTemplate(
                     tempFile.getName(),

docs/template-resolution.md

@@ -0,0 +1,45 @@
+# Template resolution strategies
+
+General intro
+
+## Local Templates Resolution Strategy
+
+Description of this approach
+
+Configuration
+```yaml
+path: sfdsfsdf
+```
+
+### File naming
+
+Template naming patters
+
+### Configuring local templates' resolution strategy for dockerized environments
+
+Paths to override and docker command examples
+
+## External Service Templates Resolution Strategy
+
+Description of this approach
+
+Configuration example 
+```yaml
+configuration:
+    example:
+        url: true
+```
+
+### External Service API Specification
+
+Implement the following API endpoints:
+
+    GET /templates/<template_name>
+        Returns the template content.
+
+Endpoints should return the following responses:
+
+    200 OK
+        The FTL template content with Content-type: text.
+    404 Not Found
+        The template does not exist.