feat: support AutoSave in built-in FileAdapter

src/main/java/org/casbin/jcasbin/persist/file_adapter/FileAdapter.java

@@ -26,6 +26,7 @@
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 /**
@@ -99,10 +100,10 @@ public void savePolicy(Model model) {
 
     private List<String> getModelPolicy(Model model, String ptype) {
         List<String> policy = new ArrayList<>();
-        model.model.get(ptype).forEach((k, v) -> {
+        Optional.ofNullable(model.model.get(ptype)).ifPresent(entry -> entry.forEach((k, v) -> {
             List<String> p = v.policy.parallelStream().map(x -> k + ", " + Util.arrayToString(x)).collect(Collectors.toList());
             policy.addAll(p);
-        });
+        }));
         return policy;
     }
 
@@ -130,15 +131,35 @@ private void savePolicyFile(String text) {
      */
     @Override
     public void addPolicy(String sec, String ptype, List<String> rule) {
-        throw new UnsupportedOperationException("not implemented");
+        String ruleText = System.lineSeparator() + ptype + ", " + String.join(", ", rule);
+        if (byteArrayInputStream != null && readOnly) {
+            throw new CasbinAdapterException("Policy file can not write, because use inputStream is readOnly");
+        }
+        try (FileOutputStream fos = new FileOutputStream(filePath, true)) {
+            IOUtils.write(ruleText, fos, Charset.forName("UTF-8"));
+        } catch (IOException e) {
+            e.printStackTrace();
+            throw new CasbinAdapterException("Policy add error");
+        }
     }
 
     /**
      * removePolicy removes a policy rule from the storage.
      */
     @Override
     public void removePolicy(String sec, String ptype, List<String> rule) {
-        throw new UnsupportedOperationException("not implemented");
+        String ruleText = ptype + ", " + String.join(", ", rule);
+        if (byteArrayInputStream != null && readOnly) {
+            throw new CasbinAdapterException("Policy file can not write, because use inputStream is readOnly");
+        }
+        try {
+            List<String> lines = IOUtils.readLines(new FileInputStream(filePath), Charset.forName("UTF-8"));
+            lines.remove(ruleText);
+            savePolicyFile(String.join("\n", lines));
+        } catch (IOException e) {
+            e.printStackTrace();
+            throw new CasbinAdapterException("Policy remove error");
+        }
     }
 
     /**

src/test/java/org/casbin/jcasbin/main/EnforcerUnitTest.java

@@ -14,8 +14,6 @@
 
 package org.casbin.jcasbin.main;
 
-import com.googlecode.aviator.AviatorEvaluator;
-import com.googlecode.aviator.Expression;
 import org.casbin.jcasbin.model.Model;
 import org.casbin.jcasbin.persist.Adapter;
 import org.casbin.jcasbin.persist.file_adapter.FileAdapter;
@@ -29,9 +27,7 @@
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.nio.file.Files;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 
@@ -365,22 +361,34 @@ public void testEnableAutoSave() {
         testEnforce(e, "bob", "data2", "write", true);
 
         e.enableAutoSave(true);
-        // Because AutoSave is enabled, the policy change not only affects the policy in Casbin enforcer,
-        // but also affects the policy in the storage.
         e.removePolicy("alice", "data1", "read");
-
-        // However, the file adapter doesn't implement the AutoSave feature, so enabling it has no effect at all here.
-
+        // Affects the policy in the memory
+        testEnforce(e, "alice", "data1", "read", false);
+        // Affects the policy in the adapter
         // Reload the policy from the storage to see the effect.
         e.loadPolicy();
-        testEnforce(e, "alice", "data1", "read", true); // Will not be false here.
+        testEnforce(e, "alice", "data1", "read", false); // Will not be false here.
         testEnforce(e, "alice", "data1", "write", false);
         testEnforce(e, "alice", "data2", "read", false);
         testEnforce(e, "alice", "data2", "write", false);
         testEnforce(e, "bob", "data1", "read", false);
         testEnforce(e, "bob", "data1", "write", false);
         testEnforce(e, "bob", "data2", "read", false);
         testEnforce(e, "bob", "data2", "write", true);
+
+        // enableAutoSave is enabled, prevent previous operations from affecting the CSV file.
+        e.addPolicy("alice", "data1", "read");
+
+        // Test group policy
+        e = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
+        testEnforce(e, "alice", "data2", "read", true);
+        e.removeGroupingPolicy("alice", "data2_admin");
+        testEnforce(e, "alice", "data2", "read", false);
+        e.loadPolicy();
+        testEnforce(e, "alice", "data2", "read", false);
+        e.addGroupingPolicy("alice", "data2_admin");
+        e.loadPolicy();
+        testEnforce(e, "alice", "data2", "read", true);
     }
 
     @Test
@@ -398,6 +406,54 @@ public void testInitWithAdapter() {
         testEnforce(e, "bob", "data2", "write", true);
     }
 
+    @Test
+    public void testFileAdapterAutoSave() {
+        Enforcer e = new Enforcer("examples/basic_model.conf", "examples/basic_policy.csv");
+
+        // test addPolicy() autoSave
+        e.enableAutoSave(false);
+        testEnforce(e, "erica", "data3", "read", false);
+        e.addPolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", true);
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", false);
+
+        e.enableAutoSave(true);
+        testEnforce(e, "erica", "data3", "read", false);
+        e.addPolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", true);
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", true);
+
+        // test removePolicy() autoSave
+        e.enableAutoSave(false);
+        e.removePolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", false);
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", true);
+        e.enableAutoSave(true);
+        e.removePolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", false);
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", false);
+
+        // test savePolicy()
+        e.enableAutoSave(false);
+        e.addPolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", true);
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", false);
+        e.addPolicy("erica", "data3", "read");
+        testEnforce(e, "erica", "data3", "read", true);
+        e.savePolicy();
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", true);
+        e.removePolicy("erica", "data3", "read");
+        e.savePolicy();
+        e.loadPolicy();
+        testEnforce(e, "erica", "data3", "read", false);
+    }
+
     @Test
     public void testRoleLinks() {
         Enforcer e = new Enforcer("examples/rbac_model.conf");
@@ -569,6 +625,7 @@ public void testPriorityExplicit() {
         testEnforce(e, "data2_allow_group", "data2", "write", true);
 
         // add a higher priority policy
+        e.enableAutoSave(false);
         e.addPolicy("bob", "data2", "write", "deny", "1");
 
         testEnforce(e, "alice", "data1", "write", true);
@@ -584,7 +641,7 @@ public void testPriorityExplicit() {
     @Test
     public void testEnforceWithMatcher() {
         Enforcer e = new Enforcer("examples/basic_model.conf", "examples/basic_policy.csv");
-
+        e.enableAutoSave(false);
         // the previous matcher is
         // m = r.sub == p.sub && r.obj == p.obj && r.act == p.act
         testEnforce(e, "alice", "data1", "read", true);

src/test/java/org/casbin/jcasbin/main/ManagementAPIUnitTest.java

@@ -69,7 +69,7 @@ public void testGetPolicyAPI() {
     @Test
     public void testModifyPolicyAPI() {
         Enforcer e = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetPolicy(e, asList(
             asList("alice", "data1", "read"),
             asList("bob", "data2", "write"),
@@ -131,7 +131,7 @@ public void testModifyPolicyAPI() {
     @Test
     public void testModifyGroupingPolicyAPI() {
         Enforcer e = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRoles(e, "alice", asList("data2_admin"));
         testGetRoles(e, "bob", asList());
         testGetRoles(e, "eve", asList());

src/test/java/org/casbin/jcasbin/main/ModelUnitTest.java

@@ -178,7 +178,7 @@ public void testRBACModelWithDomains() {
     @Test
     public void testRBACModelWithDomainsAtRuntime() {
         Enforcer e = new Enforcer("examples/rbac_with_domains_model.conf");
-
+        e.enableAutoSave(false);
         e.addPolicy("admin", "domain1", "data1", "read");
         e.addPolicy("admin", "domain1", "data1", "write");
         e.addPolicy("admin", "domain2", "data2", "read");

src/test/java/org/casbin/jcasbin/main/RbacAPIUnitTest.java

@@ -34,7 +34,7 @@ public class RbacAPIUnitTest {
     @Test
     public void testRoleAPI() {
         Enforcer e = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRoles(e, "alice", asList("data2_admin"));
         testGetRoles(e, "bob", asList());
         testGetRoles(e, "data2_admin", asList());
@@ -128,7 +128,7 @@ public void testRoleAPIWithRegex() {
     @Test
     public void testGFunctionCache() {
         Enforcer e = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testEnforce(e, "alice", "data2", "read", true);
         e.removeGroupingPolicy(Arrays.asList("alice","data2_admin"));
         // Ensure that the gFunction cache is different for each enforce

src/test/java/org/casbin/jcasbin/main/RbacAPIWithDomainsUnitTest.java

@@ -23,7 +23,7 @@ public class RbacAPIWithDomainsUnitTest {
     @Test
     public void testRoleAPIWithDomains() {
         Enforcer e = new Enforcer("examples/rbac_with_domains_model.conf", "examples/rbac_with_domains_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRolesInDomain(e, "alice", "domain1", asList("admin"));
         testGetRolesInDomain(e, "bob", "domain1", asList());
         testGetRolesInDomain(e, "admin", "domain1", asList());
@@ -51,7 +51,7 @@ public void testRoleAPIWithDomains() {
     @Test
     public void testUserAPIWithDomains() {
         Enforcer e = new Enforcer("examples/rbac_with_domains_model.conf", "examples/rbac_with_domains_policy.csv");
-
+        e.enableAutoSave(false);
         testGetUsersInDomain(e, "alice", "domain1", asList());
         testGetUsersInDomain(e, "bob", "domain1", asList());
         testGetUsersInDomain(e, "admin", "domain1", asList("alice"));

src/test/java/org/casbin/jcasbin/main/SyncedEnforcerUnitTest.java

@@ -394,22 +394,23 @@ public void testEnableAutoSave() {
         testEnforce(e, "bob", "data2", "write", true);
 
         e.enableAutoSave(true);
-        // Because AutoSave is enabled, the policy change not only affects the policy in Casbin enforcer,
-        // but also affects the policy in the storage.
         e.removePolicy("alice", "data1", "read");
-
-        // However, the file adapter doesn't implement the AutoSave feature, so enabling it has no effect at all here.
-
+        // Affects the policy in the memory
+        testEnforce(e, "alice", "data1", "read", false);
+        // Affects the policy in the adapter
         // Reload the policy from the storage to see the effect.
         e.loadPolicy();
-        testEnforce(e, "alice", "data1", "read", true); // Will not be false here.
+        testEnforce(e, "alice", "data1", "read", false); // Will not be false here.
         testEnforce(e, "alice", "data1", "write", false);
         testEnforce(e, "alice", "data2", "read", false);
         testEnforce(e, "alice", "data2", "write", false);
         testEnforce(e, "bob", "data1", "read", false);
         testEnforce(e, "bob", "data1", "write", false);
         testEnforce(e, "bob", "data2", "read", false);
         testEnforce(e, "bob", "data2", "write", true);
+
+        // enableAutoSave is enabled, prevent previous operations from affecting the CSV file.
+        e.addPolicy("alice", "data1", "read");
     }
 
     @Test

src/test/java/org/casbin/jcasbin/main/SyncedManagementAPIUnitTest.java

@@ -66,7 +66,7 @@ public void testGetPolicyAPI() {
     @Test
     public void testModifyPolicyAPI() {
         Enforcer e = new SyncedEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetPolicy(e, asList(
                 asList("alice", "data1", "read"),
                 asList("bob", "data2", "write"),
@@ -96,7 +96,7 @@ public void testModifyPolicyAPI() {
     @Test
     public void testModifyGroupingPolicyAPI() {
         Enforcer e = new SyncedEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRoles(e, "alice", asList("data2_admin"));
         testGetRoles(e, "bob", asList());
         testGetRoles(e, "eve", asList());

src/test/java/org/casbin/jcasbin/main/SyncedRbacAPIUnitTest.java

@@ -26,7 +26,7 @@ public class SyncedRbacAPIUnitTest {
     @Test
     public void testRoleAPI() {
         Enforcer e = new SyncedEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRoles(e, "alice", asList("data2_admin"));
         testGetRoles(e, "bob", asList());
         testGetRoles(e, "data2_admin", asList());

src/test/java/org/casbin/jcasbin/main/SyncedRbacAPIWithDomainsUnitTest.java

@@ -23,7 +23,7 @@ public class SyncedRbacAPIWithDomainsUnitTest {
     @Test
     public void testRoleAPIWithDomains() {
         Enforcer e = new SyncedEnforcer("examples/rbac_with_domains_model.conf", "examples/rbac_with_domains_policy.csv");
-
+        e.enableAutoSave(false);
         testGetRolesInDomain(e, "alice", "domain1", asList("admin"));
         testGetRolesInDomain(e, "bob", "domain1", asList());
         testGetRolesInDomain(e, "admin", "domain1", asList());
@@ -51,7 +51,7 @@ public void testRoleAPIWithDomains() {
     @Test
     public void testUserAPIWithDomains() {
         Enforcer e = new SyncedEnforcer("examples/rbac_with_domains_model.conf", "examples/rbac_with_domains_policy.csv");
-
+        e.enableAutoSave(false);
         testGetUsersInDomain(e, "alice", "domain1", asList());
         testGetUsersInDomain(e, "bob", "domain1", asList());
         testGetUsersInDomain(e, "admin", "domain1", asList("alice"));

src/test/java/org/casbin/jcasbin/main/WatcherTest.java

@@ -65,6 +65,7 @@ public void testSetWatcher() {
     @Test
     public void testSelfModify() {
         Enforcer enforcer = new Enforcer("examples/rbac_model.conf", "examples/rbac_policy.csv");
+        enforcer.enableAutoSave(false);
         SampleWatcher thisIsTestWatcher = new SampleWatcher();
         enforcer.setWatcher(thisIsTestWatcher);
         AtomicInteger called = new AtomicInteger(-1);