feat(central): only allow one peer per ASN on the same node

If migration failed with duplication keys, manually remove duplicated peers and repair.
Check duplicated peers:
SELECT id, asn, node, COUNT(*) FROM peer GROUP BY asn, node HAVING COUNT(*) > 1

4 files changed, 40 insertions, 14 deletions

diff --git a/central/src/main/java/moe/yuuta/dn42peering/manage/ManageHandler.java b/central/src/main/java/moe/yuuta/dn42peering/manage/ManageHandler.java
index 6b22858..4ba720a 100644
--- a/central/src/main/java/moe/yuuta/dn42peering/manage/ManageHandler.java
+++ b/central/src/main/java/moe/yuuta/dn42peering/manage/ManageHandler.java
@@ -22,10 +22,12 @@ import io.vertx.json.schema.SchemaParser;
 import io.vertx.json.schema.SchemaRouter;
 import io.vertx.json.schema.SchemaRouterOptions;
 import io.vertx.json.schema.common.dsl.ObjectSchemaBuilder;
+import io.vertx.serviceproxy.ServiceException;
 import moe.yuuta.dn42peering.admin.SudoUtils;
 import moe.yuuta.dn42peering.asn.IASNService;
 import moe.yuuta.dn42peering.jaba.Pair;
 import moe.yuuta.dn42peering.node.INodeService;
+import moe.yuuta.dn42peering.peer.DuplicatePeerException;
 import moe.yuuta.dn42peering.peer.IPeerService;
 import moe.yuuta.dn42peering.peer.Peer;
 import moe.yuuta.dn42peering.portal.FormException;
@@ -146,7 +148,14 @@ public class ManageHandler implements ISubRouter {
                         if (ar.succeeded()) {
                             peer.setId((int) (long) ar.result());
                             f.complete(peer);
-                        } else f.fail(ar.cause());
+                        } else {
+                            if(((ServiceException)ar.cause()).getDebugInfo().getString("causeName")
+                                    .equals(DuplicatePeerException.class.getName())) {
+                                f.fail(new FormException(peer, "A peer on your chosen node already exists. You can only create one peer per node."));
+                                return;
+                            }
+                            f.fail(ar.cause());
+                        }
                     })))
                             .onSuccess(peer -> {
                                 ctx.response()
diff --git a/central/src/main/java/moe/yuuta/dn42peering/peer/DuplicatePeerException.java b/central/src/main/java/moe/yuuta/dn42peering/peer/DuplicatePeerException.java
new file mode 100644
index 0000000..b80332e
--- /dev/null
+++ b/central/src/main/java/moe/yuuta/dn42peering/peer/DuplicatePeerException.java
@@ -0,0 +1,4 @@
+package moe.yuuta.dn42peering.peer;
+
+public class DuplicatePeerException extends Exception {
+}
diff --git a/central/src/main/java/moe/yuuta/dn42peering/peer/PeerServiceImpl.java b/central/src/main/java/moe/yuuta/dn42peering/peer/PeerServiceImpl.java
index 5784da2..9548815 100644
--- a/central/src/main/java/moe/yuuta/dn42peering/peer/PeerServiceImpl.java
+++ b/central/src/main/java/moe/yuuta/dn42peering/peer/PeerServiceImpl.java
@@ -3,6 +3,7 @@ package moe.yuuta.dn42peering.peer;
 import io.vertx.core.*;
 import io.vertx.core.impl.logging.Logger;
 import io.vertx.core.impl.logging.LoggerFactory;
+import io.vertx.mysqlclient.MySQLException;
 import io.vertx.sqlclient.Pool;
 import io.vertx.sqlclient.Row;
 import io.vertx.sqlclient.RowSet;
@@ -87,19 +88,30 @@ class PeerServiceImpl implements IPeerService {
     @Override
     public IPeerService addNew(@Nonnull Peer peer, @Nonnull Handler<AsyncResult<Long>> handler) {
         peer.setId(0);
-        Future.<RowSet<Peer>>future(f -> SqlTemplate
-                .forQuery(pool, "INSERT INTO peer VALUES (#{id}, #{type}, #{asn}, " +
-                        "#{ipv4}, #{ipv6}, " +
-                        "#{wg_endpoint}, #{wg_endpoint_port}, " +
-                        "#{wg_self_pubkey}, #{wg_self_privkey}, " +
-                        "#{wg_peer_pubkey}, #{wg_preshared_secret}, " +
-                        "#{provision_status}, #{mpbgp}, #{node}" +
-                        ")")
-                .mapFrom(PeerParametersMapper.INSTANCE)
-                .mapTo(PeerRowMapper.INSTANCE)
-                .execute(peer, f))
-                .compose(rows -> Future.succeededFuture(rows.property(DatabaseUtils.LAST_INSERTED_ID)))
-                .onComplete(handler);
+        Future.<Long>future(f -> {
+            Future.<RowSet<Peer>>future(f1 -> SqlTemplate
+                    .forQuery(pool, "INSERT INTO peer VALUES (#{id}, #{type}, #{asn}, " +
+                            "#{ipv4}, #{ipv6}, " +
+                            "#{wg_endpoint}, #{wg_endpoint_port}, " +
+                            "#{wg_self_pubkey}, #{wg_self_privkey}, " +
+                            "#{wg_peer_pubkey}, #{wg_preshared_secret}, " +
+                            "#{provision_status}, #{mpbgp}, #{node}" +
+                            ")")
+                    .mapFrom(PeerParametersMapper.INSTANCE)
+                    .mapTo(PeerRowMapper.INSTANCE)
+                    .execute(peer, f1))
+                    .compose(rows -> Future.succeededFuture(rows.property(DatabaseUtils.LAST_INSERTED_ID)))
+                    .onFailure(err -> {
+                        if (err instanceof MySQLException) {
+                            if (((MySQLException) err).getErrorCode() == 1062 /* Duplicate */) {
+                                f.fail(new DuplicatePeerException());
+                                return;
+                            }
+                            f.fail(err);
+                        }
+                    })
+                    .onSuccess(f::complete);
+        }).onComplete(handler);
         return this;
     }
 
diff --git a/central/src/main/resources/db/migration/V5__Peer_Node_ASN_Unique.sql b/central/src/main/resources/db/migration/V5__Peer_Node_ASN_Unique.sql
new file mode 100644
index 0000000..2678483
--- /dev/null
+++ b/central/src/main/resources/db/migration/V5__Peer_Node_ASN_Unique.sql
@@ -0,0 +1 @@
+ALTER TABLE `peer` ADD UNIQUE `Node_ASN_Unique` (`asn`, `node`);
\ No newline at end of file