Support for permission expression (complex permissions that looks like boolean expressions)

This commit is contained in:
Marc Baloup 2021-08-15 03:26:50 +02:00
parent dcfafb92cb
commit 2a3b32f489
Signed by: marcbal
GPG Key ID: BBC0FE3ABC30B893
5 changed files with 160 additions and 3 deletions

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@ -52,6 +52,12 @@
<version>4.8.108</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.fathzer</groupId>
<artifactId>javaluator</artifactId>
<version>3.0.3</version>
</dependency>
</dependencies>
<build>

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@ -101,12 +101,19 @@ public abstract class PermEntity {
public Boolean hasPermission(String permission, String server, String world) {
Boolean ret = Permissions.resolver.getEffectivePermission(name, type, permission, server, world);
if (Log.isDebugEnabled()) {
Log.debug("[Perm] For " + type.toString().toLowerCase() + " " + getName() + ", '" + permission + "' is " + ret);
}
return ret;
}
public boolean hasPermissionOr(String permission, String server, String world, boolean deflt) {
Boolean ret = hasPermission(permission, server, world);
return ret != null ? ret : deflt;
}
public boolean hasPermissionExpression(String permExpression, String server, String world) {
return PermissionExpressionParser.evaluate(permExpression, p -> hasPermissionOr(p, server, world, false));
}
public DisplayTreeNode debugPermission(String permission) {
return debugPermission(permission, null, null);

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@ -0,0 +1,115 @@
package fr.pandacube.lib.core.permissions;
import java.util.Iterator;
import java.util.function.Function;
import com.fathzer.soft.javaluator.AbstractEvaluator;
import com.fathzer.soft.javaluator.BracketPair;
import com.fathzer.soft.javaluator.Operator;
import com.fathzer.soft.javaluator.Operator.Associativity;
import com.fathzer.soft.javaluator.Parameters;
public class PermissionExpressionParser {
private static final PermissionEvaluator PERMISSION_EVALUATOR = new PermissionEvaluator();
public static boolean evaluate(String permString, LitteralPermissionTester permTester) {
try {
return PERMISSION_EVALUATOR.evaluate(permString, permTester);
} catch (IllegalArgumentException e) {
throw new IllegalArgumentException("Cant evaluate the provided permission expression: '" + permString + "'", e);
}
}
public interface LitteralPermissionTester extends Function<String, Boolean> { }
private static class PermissionEvaluator extends AbstractEvaluator<Boolean> {
private static final Operator NOT = new Operator("!", 1, Associativity.LEFT, 3);
private static final Operator AND = new Operator("&&", 2, Associativity.LEFT, 2);
private static final Operator OR = new Operator("||", 2, Associativity.LEFT, 1);
private static final Parameters PARAMETERS;
static {
PARAMETERS = new Parameters();
PARAMETERS.add(NOT);
PARAMETERS.add(AND);
PARAMETERS.add(OR);
PARAMETERS.addExpressionBracket(BracketPair.PARENTHESES);
}
public PermissionEvaluator() {
super(PARAMETERS);
}
@Override
protected Boolean toValue(String literal, Object evaluationContext) {
if (literal.contains(" ") || literal.contains("|") || literal.contains("&"))
throw new IllegalArgumentException("Unable to parse the following part of permission expression as one permission node: '" + literal + "'");
return evaluationContext instanceof LitteralPermissionTester pt ? pt.apply(literal) : false;
}
@Override
protected Boolean evaluate(Operator operator, Iterator<Boolean> operands, Object evaluationContext) {
if (operator == NOT) {
return !operands.next();
} else if (operator == OR) {
Boolean o1 = operands.next();
Boolean o2 = operands.next();
return o1 || o2;
} else if (operator == AND) {
Boolean o1 = operands.next();
Boolean o2 = operands.next();
return o1 && o2;
} else {
return super.evaluate(operator, operands, evaluationContext);
}
}
}
/*
public static void main(String[] args) {
java.util.List<String> pList = java.util.Arrays.asList("p1.cmd", "p1.toto", "p2.lol");
LitteralPermissionTester tester = p -> pList.contains(p);
for (String permExpr : java.util.Arrays.asList(
"p1.cmd", // true
"p1.notexist", // false
"p2lol.lol", // false
"!p1.notexist", // true
"!p1.cmd", // false
"p1.cmd!", // false
"p1.cmd! p2.lol", // exception
"p1.cmd || p1.toto", // true || true == true
"p1.cmd || p1.notexist", // true || false == true
"p1.fefef || p2.lol", // false || true == true
"p1.fefef || p2.lolilol", // false || false == false
"p1.cmd && p1.toto", // true && true == true
"p1.cmd && p1.notexist", // true && false == false
"p1.fefef && p2.lol", // false && true == false
"p1.fefef && p2.lolilol", // false && false == false
"p1.cmd && !p1.toto ", // true && !true == false
" !p1.cmd && p1.toto", // !true && true == false
"!p1.cmd & p1.toto", // exception
"!p1.cmd | p1.toto", // exception
"p1.not exist" // exception
)) {
try {
System.out.println(permExpr + " -> " + evaluate(permExpr, tester));
} catch (Exception e) {
e.printStackTrace();
}
}
}
*/
}

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@ -123,6 +123,27 @@ public interface IOffPlayer {
return res != null ? res : false;
}
/**
* Tells if this player has the permission resulted from the provided expression.
* If the player is online, this will redirect the
* method call to the {@link IOnlinePlayer} instance,
* that MUST override this current method to avoid recussive
* loop.
* If the player is offline, it just call the Pandacube
* permission system.
* @param permission the permission node to test
* @return whether this player has the provided permission
*/
public default boolean hasPermissionExpression(String permissionExpression) {
IOnlinePlayer online = getOnlineInstance();
if (online != null)
return online.hasPermissionExpression(permissionExpression);
// at this point, the player is offline
return getPermissionUser().hasPermissionExpression(permissionExpression, null, null);
}
/**
* Tells if the this player is part of the specified group
*

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@ -71,6 +71,14 @@ public interface IOnlinePlayer extends IOffPlayer {
*/
public abstract boolean hasPermission(String permission);
/**
* Tells if this online player has the permission resulted from the provided expression.
* @implSpec the implementation of this method must not directly or
* indirectly call the method {@link IOffPlayer#hasPermissionExpression(String)},
* or it may result in a {@link StackOverflowError}.
*/
public abstract boolean hasPermissionExpression(String permission);