DSE Geospatial Types

DSE 5.0 included a graph-oriented database queried utilizing the Gremlin graph language. Graph queries are executed using Dse\Session::executeGraph() or Dse\Session::executeGraphAsync().

Background

Given

a running DSE cluster with graph

And

an existing graph called “users” with schema:

schema.propertyKey('name').Text().ifNotExists().create();
schema.propertyKey('age').Int().ifNotExists().create();
schema.propertyKey('lang').Text().ifNotExists().create();
schema.propertyKey('weight').Float().ifNotExists().create();
schema.vertexLabel('person').properties('name', 'age').ifNotExists().create();
schema.vertexLabel('software').properties('name', 'lang').ifNotExists().create();
schema.edgeLabel('created').properties('weight').connection('person', 'software').ifNotExists().create();
schema.edgeLabel('knows').properties('weight').connection('person', 'person').ifNotExists().create();
schema.propertyKey('country').Text().ifNotExists().create();
schema.propertyKey('origin').Text().multiple().properties('country').ifNotExists().create();
schema.vertexLabel('master').properties('name', 'origin').ifNotExists().create();
schema.vertexLabel('character').properties('name').ifNotExists().create();

Create and query vertex with graph options

Given

the following example:

$graphOptions = Dse::graphOptions()
  ->withGraphName("users")
  ->withGraphSource("g")
  ->withGraphLanguage("gremlin-groovy")
  ->withReadConsistency(Dse::CONSISTENCY_ONE)
  ->withWriteConsistency(Dse::CONSISTENCY_ONE)
  ->withRequestTimeout(1)
  ->build();

$cluster = Dse::cluster()
  ->withGraphOptions($graphOptions)
  ->build();
$session = $cluster->connect();

$session->executeGraph("Vertex marko = graph.addVertex(label, 'person', 'name', 'marko', 'age', 29);");

$resultset = $session->executeGraph("g.V().has('name', 'marko')[0]");
$vertex = $resultset->first()->asVertex();

echo "Vertex label: {$vertex->id()['~label']}" . PHP_EOL;

foreach($vertex->properties() as $property) {
  echo "Vertex property name: {$property->name()}" . PHP_EOL;
  foreach ($property->value() as $value) {
    echo "Vertex property value: {$value['value']}" . PHP_EOL;
  }
}

When

it is executed

Then

its output should contain:

Vertex label: person
Vertex property name: name
Vertex property value: marko
Vertex property name: age
Vertex property value: 29

Create and query edges

Given

the following example:

$graphOptions = Dse::graphOptions()
  ->withGraphName("users")
  ->build();

$cluster = Dse::cluster()
  ->withGraphOptions($graphOptions)
  ->build();
$session = $cluster->connect();

$session->executeGraph(
  "Vertex marko = graph.addVertex(label, 'person', 'name', 'marko', 'age', 29);
   Vertex vadas = graph.addVertex(label, 'person', 'name', 'vadas', 'age', 27);
   marko.addEdge('knows', vadas, 'weight', 0.5f);");

$resultset = $session->executeGraph("g.V().has('name', 'marko').outE('knows')");
$edge = $resultset->first()->asEdge();

echo "Edge type: {$edge->id()['~type']}" . PHP_EOL;
echo "Edge incoming vertex label: {$edge->inVLabel()}" . PHP_EOL;
echo "Edge outgoing vertex label: {$edge->outVLabel()}" . PHP_EOL;

foreach($edge->properties() as $property) {
  echo "Edge property name: {$property->name()}" . PHP_EOL;
  echo "Edge property value: {$property->value()}" . PHP_EOL;
}

When

it is executed

Then

its output should contain:

Edge type: knows
Edge incoming vertex label: person
Edge outgoing vertex label: person
Edge property name: weight
Edge property value: 0.5

Using paths

Given

the following example:

$graphOptions = Dse::graphOptions()
  ->withGraphName("users")
  ->build();

$cluster = Dse::cluster()
  ->withGraphOptions($graphOptions)
  ->build();
$session = $cluster->connect();

$session->executeGraph(
  "Vertex marko = graph.addVertex(label, 'person', 'name', 'marko', 'age', 29);
   Vertex vadas = graph.addVertex(label, 'person', 'name', 'vadas', 'age', 27);
   Vertex lop = graph.addVertex(label, 'software', 'name', 'lop', 'lang', 'java');
   Vertex josh = graph.addVertex(label, 'person', 'name', 'josh', 'age', 32);
   Vertex ripple = graph.addVertex(label, 'software', 'name', 'ripple', 'lang', 'java');
   Vertex peter = graph.addVertex(label, 'person', 'name', 'peter', 'age', 35);
   marko.addEdge('knows', vadas, 'weight', 0.5f);
   marko.addEdge('knows', josh, 'weight', 1.0f);
   marko.addEdge('created', lop, 'weight', 0.4f);
   josh.addEdge('created', ripple, 'weight', 1.0f);
   josh.addEdge('created', lop, 'weight', 0.4f);
   peter.addEdge('created', lop, 'weight', 0.2f);");


$resultset = $session->executeGraph(
  "g.V().hasLabel('person').has('name', 'marko').as('a').outE('knows').inV().as('c', 'd').outE('created').as('e', 'f', 'g').inV().path()");

$path = $resultset->first()->asPath();

echo "Path labels: " . json_encode($path->labels()) . PHP_EOL;
echo "Length of path: " . count($path->labels()) . PHP_EOL;

$objects = $path->objects();
for ($i = 0; $i < count($objects); $i++) {
  try {
    $vertex = $objects[$i]->asVertex();
    echo "Object $i is a(n) " . get_class($vertex) . " with the value: " . $vertex->property('name')->value()[0]['value'] . PHP_EOL;
  } catch(Dse\Exception\DomainException $e) {
    $edge = $objects[$i]->asEdge();
    echo "Object $i is a(n) " . get_class($edge) . " with the value: " . $edge->label(). PHP_EOL;
  }
}

When

it is executed

Then

its output should contain:

Path labels: [["a"],[],["c","d"],["e","f","g"],[]]
Length of path: 5
Object 0 is a(n) Dse\Graph\DefaultVertex with the value: marko
Object 1 is a(n) Dse\Graph\DefaultEdge with the value: knows
Object 2 is a(n) Dse\Graph\DefaultVertex with the value: josh
Object 3 is a(n) Dse\Graph\DefaultEdge with the value: created
Object 4 is a(n) Dse\Graph\DefaultVertex with the value: lop

Inspecting a simple result

Given

the following example:

$graphOptions = Dse::graphOptions()
  ->withGraphName("users")
  ->build();

$cluster = Dse::cluster()
  ->withGraphOptions($graphOptions)
  ->build();
$session = $cluster->connect();

$resultset = $session->executeGraph("g.V().has('name', 'marko')[0].property('age').value()");
$result = $resultset->first();

echo "The result type is a number? " . ($result->isNumber() ? "true" : "false") . PHP_EOL;
echo "The result value is: {$result}" . PHP_EOL;

When

it is executed

Then

its output should contain:

The result type is a number? true
The result value is: 29