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There should only be an initial snapshot if a specific model instance was passed to Engine.Create.

The modules are included in the core repository. Create a single repository for each module.

Can't reload from an existing FileCommandStore

Using Windows 10 operating system.
OrigoDB version 0.2.
No modified configuration files, extracted to hard disk and ran Windows Service install batch file.

Windows batch file created new app config file in the following folder:
C:\Windows\scripts

The contents:

<configuration>
    <appSettings>
        <add key="AdminHost" value="127.0.0.1" />
        <add key="AdminPort" value="8080" />
    </appSettings>
</configuration>

Therefore the Windows Service bound on the port 8080 and not 8088 as specified in the original config file.

Even when PersistenceMode is set to ManualSnapshots, an initial journal entry is still created on disk. Not sure if there’s any way to avoid/defer this for cases when the database is intended to be ephemeral.

The ProxyMethodMap class maps method names to methodinfo using a Dictionary<string,MethodInfo>. Overloads will throw while the map is being built.

Proxy writes ProxyCommand objects to the journal containing the name of the method and an array with the arguments. The solution should be backwards compatible with existing journals.

Model.Revision should increment for every command executed which is not the case.

Add xml doc comments to source and generate API docs.

Command exceptions should propagate through the proxy instead of throwing TargetInvocationException

There are 25 remaining MSTest unit tests in the project OrigoDB.Test.MSTest. Rewrite and move to the NUnit project.

Create a helper to enumerate all the Origo related types in an assembly. Models, Commands, Queries, EngineConfigurations and custom extensions implementing origo interfaces.

Useful for developer but also supports toolmaking and origodb server features.

Create a module with an IFormatter based on https://github.com/msgpack/msgpack-cli

Add Engine.Load overloads which load to a specific point in time based on either Revision or DateTime, or Func<JournalEntry<Command>,bool>. The resulting engine should be in a read only or non-persisting mode.

Sequence numbers restart from 1 after a reload

The Timestamp property is assigned from a method tagged [OnDeserialized] which isn't invoked by the protobuf-net formatter.

Users should be able to use the CRUD pattern to store entities objects of any type. Entities that refer to each other should use foreign keys, not references.
Something like:

  var db = Db.For<Relational>();
  db.CreateTable<Product>();
  var product = new Product();
  db.Insert(product);
  product.Name = "Coconuts";
  db.Update(product);
  db.Delete(product);

Some things to discuss:

Identity

Each entity needs to have a unique identity. We could allow a [Key] attribute on one or more fields, look for a field named Id or just let the user implement IComparable on each Entity. We could support all of these or a subset.

Generated keys

User assigned numeric keys is a problem, there is a risk for duplicates. We could just recommend guids but that takes away options from the user. Also guids use more memory than integer types.
If the server generates during INSERT we might need the generated value to set as FK in related entities. These may also have to be in the same transaction.

Constraints

Constraints should probably be on the entity itself, using plain OO. Except unique constraints, we could use indexes for that.

Indexes

Creating indexes would be useful. Something like:
db.Index<Product>("Product.Name", p => p.Name);
We would have to serialize the lambda to make this work with a remote server.

How will origodb server know the user defined entity types?

Running embedded the user can put custom entities in a generic model but remote, the server needs to be able to load the types. One way would be to just add assemblies in the server UI but this kind of defeats the purpose of a generic model in the first place.

Here's an old blog article with some ideas
http://origodb.com/2011/11/24/relational-modeling-and-crud.html
EDIT: Link updated

JournalEntry.Id was changed from long to ulong in version 0.12. Loading a journal written with an earlier version will fail.

The docs have moved to http://dev.origodb.com/docs. Ensure everything on the wiki have been copied, then delete them.