diff options
author | Harald Musum <musum@verizonmedia.com> | 2019-06-16 16:31:13 +0200 |
---|---|---|
committer | GitHub <noreply@github.com> | 2019-06-16 16:31:13 +0200 |
commit | e70699d0afc96eff24de38aafed73f67b0c5690f (patch) | |
tree | da58331a0c8e489cc09a8d95a10bd6ff782d89c4 /node-repository | |
parent | 56d4744194e2684077b9585780e65a6912bf181d (diff) | |
parent | 0cf99d39c5fe547bda186112f9d7e2924305d45c (diff) |
Merge pull request #9817 from vespa-engine/bratseth/serialization-warning
Bratseth/serialization warning
Diffstat (limited to 'node-repository')
2 files changed, 11 insertions, 4 deletions
diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/LoadBalancerSerializer.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/LoadBalancerSerializer.java index a4b915a6128..fd2294c1b5d 100644 --- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/LoadBalancerSerializer.java +++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/LoadBalancerSerializer.java @@ -27,6 +27,13 @@ import java.util.function.Function; */ public class LoadBalancerSerializer { + // WARNING: Since there are multiple servers in a ZooKeeper cluster and they upgrade one by one + // (and rewrite all nodes on startup), changes to the serialized format must be made + // such that what is serialized on version N+1 can be read by version N: + // - ADDING FIELDS: Always ok + // - REMOVING FIELDS: Stop reading the field first. Stop writing it on a later version. + // - CHANGING THE FORMAT OF A FIELD: Don't do it bro. + private static final String idField = "id"; private static final String hostnameField = "hostname"; private static final String dnsZoneField = "dnsZone"; diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/NodeSerializer.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/NodeSerializer.java index d38a6e5031c..424889caf72 100644 --- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/NodeSerializer.java +++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/persistence/NodeSerializer.java @@ -44,12 +44,12 @@ import java.util.function.UnaryOperator; */ public class NodeSerializer { - // WARNING: Since there are multiple config servers in a cluster and they upgrade one by one - // (and rewrite all nodes on startup), - // changes to the serialized format must be made such that what is serialized on version N+1 - // can be read by version N: + // WARNING: Since there are multiple servers in a ZooKeeper cluster and they upgrade one by one + // (and rewrite all nodes on startup), changes to the serialized format must be made + // such that what is serialized on version N+1 can be read by version N: // - ADDING FIELDS: Always ok // - REMOVING FIELDS: Stop reading the field first. Stop writing it on a later version. + // - CHANGING THE FORMAT OF A FIELD: Don't do it bro. /** The configured node flavors */ private final NodeFlavors flavors; |