Allow for extension of test suite from 3rd party SOP implementations

external-sop/src/test/java/sop/testsuite/external/ExternalSOPInstanceFactory.java

@@ -0,0 +1,75 @@
+// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package sop.testsuite.external;
+
+import com.google.gson.Gson;
+import sop.SOP;
+import sop.external.ExternalSOP;
+import sop.testsuite.SOPInstanceFactory;
+
+import java.io.File;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+
+public class ExternalSOPInstanceFactory extends SOPInstanceFactory {
+
+    @Override
+    public Map<String, SOP> provideSOPInstances() {
+        Map<String, SOP> backends = new HashMap<>();
+        TestSuite suite = readConfiguration();
+        if (suite != null && !suite.backends.isEmpty()) {
+            for (TestSubject subject : suite.backends) {
+                if (!new File(subject.sop).exists()) {
+                    continue;
+                }
+
+                Properties env = new Properties();
+                if (subject.env != null) {
+                    for (Var var : subject.env) {
+                        env.put(var.key, var.value);
+                    }
+                }
+
+                SOP sop = new ExternalSOP(subject.sop, env);
+                backends.put(subject.name, sop);
+            }
+        }
+        return backends;
+    }
+
+
+    public static TestSuite readConfiguration() {
+        Gson gson = new Gson();
+        InputStream inputStream = ExternalSOPInstanceFactory.class.getResourceAsStream("config.json");
+        if (inputStream == null) {
+            return null;
+        }
+
+        InputStreamReader reader = new InputStreamReader(inputStream);
+        return gson.fromJson(reader, TestSuite.class);
+    }
+
+
+    // JSON DTOs
+
+    public static class TestSuite {
+        List<TestSubject> backends;
+    }
+
+    public static class TestSubject {
+        String name;
+        String sop;
+        List<Var> env;
+    }
+
+    public static class Var {
+        String key;
+        String value;
+    }
+}