12.3 Publishing a Preloaded Graph

The publishing behavior for preloaded graphs can be controlled in the configuration. Unless a different behavior is configured, (only) the first loaded snapshot of a graph is published. Preloaded published graphs remain in memory even if they are not used by any session.

There are two options to control the publishing behavior:

• Set the optional flag publish to true, to publish only the graph but no future snapshots of the graph. This is the default behavior as the default value of this flag is true.
• Set the optional flag publish_with_snapshots to true, to publish the graph and all future snapshots of the graph. The default value is false.

Only one of these two flags can be set to true at a time. However, publishing the graph with snapshots does also publish the first version of the graph.

Example 12-1 Sample Configuration File for Preloading Graphs

This example pgx.conf specifies two graphs for loading into memory during the graph server (PGX) startup-time. my-graph is published with snapshots while my-other-graph is published without snapshots.

{ 
  "enterprise_scheduler_config": {
    "analysis_task_config": {
      "max_threads": 32
    }
  },
  "preload_graphs": [
    {
      "path": "graph-configs/my-graph.bin.json",
      "name": "my-graph",
      "publish": false,
      "publish_with_snapshots": true
    },
    {
      "path": "graph-configs/my-other-graph.adj.json",
      "name": "my-other-graph"      
    }
  ],
  "authorization": [{
    "pgx_role": "GRAPH_DEVELOPER",
    "pgx_permissions": [{
      "preloaded_graph": "my-graph",
      "grant": "read"
    },
    {
      "preloaded_graph": "my-other-graph",
      "grant": "read"
    }]
  },	
	....
  ]
}

The two preloaded graphs can be accessed as follows:

PgxGraph g1 = session.getGraph("my-graph"); //returns the most recent available snapshot
PgxGraph g2 = session.getGraph("my-other-graph");