Janusgraph schema generator and updater
$ dotnet add package IvetIvet is a command line tool created to generate a schema for a janusgraph database and apply this schema. It has been inspired from Doctrine behaviour. The generate command creates a json file containing commands to execute. The file can be manually modified if you find migration is not complete or does not cover all you deserves. To keep trace of all applied migrations, migration names are saved into janusgraph server when upgrade is called. You can check at any moment the list of migrations both applied and not.
Docker image is available there:
To use Docker image, run the following command replacing MyDir with your local directory
docker run -v MyDir:/app/Migrations -e ip=localhost ivet
See upgrade command to add your own parameters.
You can install Ivet as a dotnet tool
dotnet tool install --global Ivet
All versions are available on https://www.nuget.org/packages/Ivet
After the package is installed you can use it like
Ivet list --input "C:\MigrationFiles"
Add Ivet.Model (https://www.nuget.org/packages/Ivet.Model) to your project. You are now ready to tag your code.
All names and possibilities are listed in Janusgraph documentation at https://docs.janusgraph.org/schema/.
Tag a Vertex:
[Vertex]
public class MyVertex
{
[PropertyKey]
[PrimaryKey()]
public string Id { get; set; }
[PropertyKey(Name="NewName", Cardinality=Cardinality.SINGLE)]
public string ANamedProperty { get; set; }
[EdgeProperty]
public List<Vertex3> AListProperty { get; private set; } = new List<Vertex3>();
[EdgeProperty]
public Vertex3[] AnArrayProperty { get; private set; } = Array.Empty<Vertex3>();
}
You can also specify a different name or a cardinality (details at https://docs.janusgraph.org/schema/#property-key-cardinality):
[PropertyKey(Name="NewName", Cardinality=Cardinality.SINGLE)]
public string ANamedProperty { get; set; }
Tag an Edge:
[Edge(typeof(MyVertex1), typeof(MyVertex2))]
[Edge(typeof(MyVertex1), typeof(MyVertex3))]
public class EdgeWithProperties
{
[PropertyKey]
public int AProperty { get; set; }
}
You can also tag a property to be used with an index (https://docs.janusgraph.org/schema/index-management/index-performance/):
[Vertex]
public class MyVertex
{
[PropertyKey]
[CompositeIndex("unicity_index", IsUnique = true)] // Set unicity of the data
public string ACompositeIndexProperty { get; set; }
[PropertyKey]
[MixedIndex("vertex2_mixed", Backend = "search", Mapping = MappingType.TEXTSTRING)]
public string SearchProperty { get; set; }
}
Index operations (awaitGraphIndexStatus, REINDEX) can take a long time. By default, generated index scripts include a 5-minute evaluation timeout (300000 ms).
You can control the timeout at three levels (highest priority first):
"evaluationTimeout": 600000 inside a script entry"evaluationTimeout": 600000 at the migration file level--timeout 600000 on the upgrade commandIvet upgrade --input ".\Migrations" --timeout 600000
[!NOTE] If an index script times out, the migration is still marked as applied. JanusGraph registers the index operation and will complete it on restart. Re-running the same script would fail with "index already exists". Scripts without an explicit timeout (e.g., entity creation scripts) are NOT marked as applied on timeout — the error propagates normally.
You can now run a generate command in order to create migration files.
[!NOTE] Many files are created by the
generatecommand. One contains vertices and edges and properties. Indices are in different files to avoid timeout at migration time.
You can have some details of migrations with list.
[!TIP] You can open and manually edit your migration files. In particular there is a description field whose content can be seen with
listcommand
> Ivet list --input ".\Migrations"
Directory: D:\Migrations
Migrations:
--------------------------------------------------------------------------------------------------------------------------
| Name | Relative path | Description | Date | Multi? | Timeout |
--------------------------------------------------------------------------------------------------------------------------
| Migration_202403032330_#0 | 12\Migration_202403032330.json | [0] | 10/03/2024 14:21:54 | True | |
--------------------------------------------------------------------------------------------------------------------------
| Migration_202403032330_#1 | 12\Migration_202403032330.json | [1] | 10/03/2024 14:22:04 | True | 300000ms |
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| Migration_202403032330_#2 | 12\Migration_202403032330.json | [2] | 10/03/2024 14:22:14 | True | 300000ms |
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