1 # This file is part of NIT ( http://www.nitlanguage.org ).
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
15 # Neo4j connector through its JSON REST API using curl.
17 # For ease of use and testing this module provide a wrapper to the `neo4j` command:
19 # # Start the Neo4j server
20 # var srv = new Neo4jServer
21 # assert srv.start_quiet
23 # In order to connect to Neo4j you need a connector:
25 # # Create new Neo4j client
26 # var client = new Neo4jClient("http://localhost:7474")
29 # The fundamental units that form a graph are nodes and relationships.
31 # Nodes are used to represent entities stored in base:
33 # # Create a disconnected node
34 # var andres = new NeoNode
35 # andres["name"] = "Andres"
36 # # Connect the node to Neo4j
37 # client.save_node(andres)
38 # assert andres.is_linked
40 # # Create a second node
41 # var kate = new NeoNode
42 # kate["name"] = "Kate"
43 # client.save_node(kate)
44 # assert kate.is_linked
46 # Relationships between nodes are a key part of a graph database.
47 # They allow for finding related data. Just like nodes, relationships can have properties.
49 # # Create a relationship
50 # var loves = new NeoEdge(andres, "LOVES", kate)
51 # client.save_edge(loves)
52 # assert loves.is_linked
54 # Nodes can also be loaded fron Neo4j:
56 # # Get a node from DB and explore edges
57 # var url = andres.url.to_s
58 # var from = client.load_node(url)
59 # assert from["name"].to_s == "Andres"
60 # var to = from.out_nodes("LOVES").first # follow the first LOVES relationship
61 # assert to["name"].to_s == "Kate"
63 # For more details, see http://docs.neo4j.org/chunked/milestone/rest-api.html
69 # Handles Neo4j server start and stop command
71 # `neo4j` binary must be in `PATH` in order to work
74 # Start the local Neo4j server instance
76 sys
.system
("neo4j start console")
80 # Like `start` but redirect the console output to `/dev/null`
81 fun start_quiet
: Bool do
82 sys
.system
("neo4j start console > /dev/null")
86 # Stop the local Neo4j server instance
88 sys
.system
("neo4j stop")
92 # Like `stop` but redirect the console output to `/dev/null`
93 fun stop_quiet
: Bool do
94 sys
.system
("neo4j stop > /dev/null")
99 # `Neo4jClient` is needed to communicate through the REST API
101 # var client = new Neo4jClient("http://localhost:7474")
102 # assert client.is_ok
105 # Neo4j REST services baseurl
107 # REST service to get node data
108 private var node_url
: String
109 # REST service to batch
110 private var batch_url
: String
111 # REST service to send cypher requests
112 private var cypher_url
: String
114 private var curl
= new Curl
116 init(base_url
: String) do
117 self.base_url
= base_url
118 var root
= service_root
119 assert root
isa JsonObject else
120 sys
.stderr
.write
"Neo4jClientError: cannot connect to server at <{base_url}>.\n"
122 self.node_url
= root
["node"].to_s
123 self.batch_url
= root
["batch"].to_s
124 self.cypher_url
= root
["cypher"].to_s
127 fun service_root
: Jsonable do return get
("{base_url}/db/data")
129 # Is the connection with the Neo4j server ok?
130 fun is_ok
: Bool do return service_root
isa JsonObject
134 cypher
(new CypherQuery.from_string
("MATCH (n) OPTIONAL MATCH n-[r]-() DELETE r, n"))
138 var errors
= new Array[String]
140 # Nodes view stored locally
141 private var local_nodes
= new HashMap[String, nullable NeoNode]
143 # Save the node in base
145 # var client = new Neo4jClient("http://localhost:7474")
148 # var andres = new NeoNode
149 # andres["name"] = "Andres"
150 # client.save_node(andres)
151 # assert andres.is_linked
153 # Once linked, nodes cannot be created twice:
155 # var oldurl = andres.url
156 # client.save_node(andres) # do nothing
157 # assert andres.url == oldurl
158 fun save_node
(node
: NeoNode): Bool do
159 if node
.is_linked
then return true
161 var batch
= new NeoBatch(self)
162 batch
.save_node
(node
)
163 # batch.create_edges(node.out_edges)
164 var errors
= batch
.execute
165 if not errors
.is_empty
then
166 errors
.add_all errors
169 local_nodes
[node
.url
.to_s
] = node
173 # Load a node from base
174 # Data, labels and edges will be loaded lazily.
175 fun load_node
(url
: String): NeoNode do
176 if local_nodes
.has_key
(url
) then
177 var node
= local_nodes
[url
]
178 if node
!= null then return node
180 var node
= new NeoNode.from_neo
(self, url
)
181 local_nodes
[url
] = node
185 # Remove the entity from base
186 fun delete_node
(node
: NeoNode): Bool do
187 if not node
.is_linked
then return false
188 var url
= node
.url
.to_s
190 local_nodes
[url
] = null
195 # Edges view stored locally
196 private var local_edges
= new HashMap[String, nullable NeoEdge]
198 # Save the edge in base
199 # From and to nodes will be created.
201 # var client = new Neo4jClient("http://localhost:7474")
203 # var andres = new NeoNode
204 # var kate = new NeoNode
205 # var edge = new NeoEdge(andres, "LOVES", kate)
206 # client.save_edge(edge)
207 # assert andres.is_linked
208 # assert kate.is_linked
209 # assert edge.is_linked
210 fun save_edge
(edge
: NeoEdge): Bool do
211 if edge
.is_linked
then return true
213 edge
.from
.out_edges
.add edge
214 edge
.to
.in_edges
.add edge
215 var batch
= new NeoBatch(self)
216 batch
.save_edge
(edge
)
217 var errors
= batch
.execute
218 if not errors
.is_empty
then
219 errors
.add_all errors
222 local_edges
[edge
.url
.to_s
] = edge
226 # Load a edge from base
227 # Data will be loaded lazily.
228 fun load_edge
(url
: String): NeoEdge do
229 if local_edges
.has_key
(url
) then
230 var node
= local_edges
[url
]
231 if node
!= null then return node
233 var edge
= new NeoEdge.from_neo
(self, url
)
234 local_edges
[url
] = edge
238 # Remove the edge from base
239 fun delete_edge
(edge
: NeoEdge): Bool do
240 if not edge
.is_linked
then return false
241 var url
= edge
.url
.to_s
243 local_edges
[url
] = null
248 # Retrieve all nodes with specified `lbl`
250 # var client = new Neo4jClient("http://localhost:7474")
252 # var andres = new NeoNode
253 # andres.labels.add_all(["Human", "Male"])
254 # client.save_node(andres)
255 # var kate = new NeoNode
256 # kate.labels.add_all(["Human", "Female"])
257 # client.save_node(kate)
259 # var nodes = client.nodes_with_label("Human")
260 # assert nodes.has(andres)
261 # assert nodes.has(kate)
262 fun nodes_with_label
(lbl
: String): Array[NeoNode] do
263 var res
= get
("{base_url}/db/data/label/{lbl.to_percent_encoding}/nodes")
264 var nodes
= new Array[NeoNode]
265 for json
in res
.as(JsonArray) do
266 var obj
= json
.as(JsonObject)
267 var node
= load_node
(obj
["self"].to_s
)
268 node
.internal_properties
= obj
["data"].as(JsonObject)
274 # Retrieve nodes belonging to all the specified `labels`.
276 # var client = new Neo4jClient("http://localhost:7474")
278 # var andres = new NeoNode
279 # andres.labels.add_all(["Human", "Male"])
280 # client.save_node(andres)
281 # var kate = new NeoNode
282 # kate.labels.add_all(["Human", "Female"])
283 # client.save_node(kate)
285 # var nodes = client.nodes_with_labels(["Human", "Male"])
286 # assert nodes.has(andres)
287 # assert not nodes.has(kate)
288 fun nodes_with_labels
(labels
: Array[String]): Array[NeoNode] do
289 assert not labels
.is_empty
292 var buffer
= new RopeBuffer
293 buffer
.append
"match n where \{label_0\} in labels(n)"
294 for i
in [1..labels
.length
[ do
295 buffer
.append
" and \{label_{i}\} in labels(n)"
297 buffer
.append
" return n"
298 var query
= new CypherQuery.from_string
(buffer
.write_to_string
)
299 for i
in [0..labels
.length
[ do
300 query
.params
["label_{i}"] = labels
[i
]
303 # Retrieve the answer.
304 var res
= cypher
(query
)
305 var nodes
= new Array[NeoNode]
306 for json
in res
.as(JsonObject)["data"].as(JsonArray) do
307 var obj
= json
.as(JsonArray).first
.as(JsonObject)
308 var node
= load_node
(obj
["self"].to_s
)
309 node
.internal_properties
= obj
["data"].as(JsonObject)
315 # Perform a `CypherQuery`
317 fun cypher
(query
: CypherQuery): Jsonable do
318 return post
("{cypher_url}", query
.to_rest
)
321 # GET JSON data from `url`
322 fun get
(url
: String): Jsonable do
323 var request
= new JsonGET(url
, curl
)
324 var response
= request
.execute
325 return parse_response
(response
)
328 # POST `params` to `url`
329 fun post
(url
: String, params
: Jsonable): Jsonable do
330 var request
= new JsonPOST(url
, curl
)
331 request
.data
= params
332 var response
= request
.execute
333 return parse_response
(response
)
336 # PUT `params` at `url`
337 fun put
(url
: String, params
: Jsonable): Jsonable do
338 var request
= new JsonPUT(url
, curl
)
339 request
.data
= params
340 var response
= request
.execute
341 return parse_response
(response
)
345 fun delete
(url
: String): Jsonable do
346 var request
= new JsonDELETE(url
, curl
)
347 var response
= request
.execute
348 return parse_response
(response
)
351 # Parse the cURL `response` as a JSON string
352 private fun parse_response
(response
: CurlResponse): Jsonable do
353 if response
isa CurlResponseSuccess then
354 var str
= response
.body_str
355 if str
.is_empty
then return new JsonObject
356 var res
= str
.parse_json
357 if res
isa JsonParseError then
358 var e
= new NeoError(res
.to_s
, "JsonParseError")
363 # empty response wrap it in empty object
364 return new JsonObject
365 else if res
isa JsonObject and res
.has_key
("exception") then
366 var error
= "Neo4jError::{res["exception"] or else "null"}"
368 if res
.has_key
("message") then
369 msg
= res
["message"].to_s
371 return new NeoError(msg
, error
)
375 else if response
isa CurlResponseFailed then
376 return new NeoError("{response.error_msg} ({response.error_code})", "CurlError")
378 return new NeoError("Unexpected response \"{response}\
".", "CurlError")
383 # A Cypher query for Neo4j REST API
385 # The Neo4j REST API allows querying with Cypher.
386 # The results are returned as a list of string headers (columns), and a data part,
387 # consisting of a list of all rows, every row consisting of a list of REST representations
388 # of the field value - Node, Relationship, Path or any simple value like String.
392 # var client = new Neo4jClient("http://localhost:7474")
393 # var query = new CypherQuery
394 # query.nmatch("(n)-[r:LOVES]->(m)")
395 # query.nwhere("n.name=\"Andres\"")
396 # query.nreturn("m.name")
397 # var res = client.cypher(query).as(JsonObject)
398 # assert res["data"].as(JsonArray).first.as(JsonArray).first == "Kate"
400 # For more details, see: http://docs.neo4j.org/chunked/milestone/rest-api-cypher.html
402 # Query string to perform
403 private var query
: String = ""
405 # `params` to embed in the query like in prepared statements
406 var params
= new JsonObject
410 # init the query from a query string
411 init from_string
(query
: String) do
415 # init the query with parameters
416 init with_params
(params
: JsonObject) do
420 # Add a `CREATE` statement to the query
421 fun ncreate
(query
: String): CypherQuery do
422 self.query
= "{self.query}CREATE {query} "
426 # Add a `START` statement to the query
427 fun nstart
(query
: String): CypherQuery do
428 self.query
= "{self.query}START {query} "
432 # Add a `MATCH` statement to the query
433 fun nmatch
(query
: String): CypherQuery do
434 self.query
= "{self.query}MATCH {query} "
438 # Add a `WHERE` statement to the query
439 fun nwhere
(query
: String): CypherQuery do
440 self.query
= "{self.query}WHERE {query} "
444 # Add a `AND` statement to the query
445 fun nand
(query
: String): CypherQuery do
446 self.query
= "{self.query}AND {query} "
450 # Add a `RETURN` statement to the query
451 fun nreturn
(query
: String): CypherQuery do
452 self.query
= "{self.query}RETURN {query} "
456 # Translate the query to the body of a corresponding Neo4j REST request.
457 fun to_rest
: JsonObject do
458 var obj
= new JsonObject
460 if not params
.is_empty
then
461 obj
["params"] = params
466 redef fun to_s
do return to_rest
.to_s
469 # The fundamental units that form a graph are nodes and relationships.
471 # Entities can have two states:
473 # * linked: the NeoEntity references an existing node or edge in Neo4j
474 # * unlinked: the NeoEntity is not yet created in Neo4j
476 # If the entity is initialized unlinked from neo4j:
478 # # Create a disconnected node
479 # var andres = new NeoNode
480 # andres["name"] = "Andres"
481 # # At this point, the node is not linked
482 # assert not andres.is_linked
484 # Then we can link the entity to the base:
487 # var client = new Neo4jClient("http://localhost:7474")
488 # client.save_node(andres)
489 # # The node is now linked
490 # assert andres.is_linked
492 # Entities can also be loaded from Neo4j:
494 # # Get a node from Neo4j
495 # var url = andres.url.to_s
496 # var node = client.load_node(url)
497 # assert node.is_linked
499 # When working in connected mode, all reading operations are executed lazily on the base:
501 # # Get the node `name` property
502 # assert node["name"] == "Andres" # loaded lazily from base
503 abstract class NeoEntity
504 # Neo4j client connector
505 private var neo
: Neo4jClient is noinit
507 # Entity unique URL in Neo4j REST API
508 var url
: nullable String = null
510 # Temp id used in batch mode to update the entity
511 private var batch_id
: nullable Int = null
513 # Load the entity from base
514 private init from_neo
(neo
: Neo4jClient, url
: String) do
519 # Init entity from JSON representation
520 private init from_json
(neo
: Neo4jClient, obj
: JsonObject) do
522 self.url
= obj
["self"].to_s
523 self.internal_properties
= obj
["data"].as(JsonObject)
526 # Create a empty (and not-connected) entity
528 self.internal_properties
= new JsonObject
531 # Is the entity linked to a Neo4j database?
532 fun is_linked
: Bool do return url
!= null
534 # In Neo4j, both nodes and relationships can contain properties.
535 # Properties are key-value pairs where the key is a string.
536 # Property values are JSON formatted.
538 # Properties are loaded lazily
539 fun properties
: JsonObject do return internal_properties
or else load_properties
541 private var internal_properties
: nullable JsonObject = null
543 private fun load_properties
: JsonObject do
544 var obj
= neo
.get
("{url.to_s}/properties").as(JsonObject)
545 internal_properties
= obj
549 # Get the entity `id` if connected to base
550 fun id
: nullable Int do
551 if url
== null then return null
552 return url
.split
("/").last
.to_i
555 # Get the entity property at `key`
556 fun [](key
: String): nullable Jsonable do
557 if not properties
.has_key
(key
) then return null
558 return properties
[key
]
561 # Set the entity property `value` at `key`
562 fun []=(key
: String, value
: nullable Jsonable) do properties
[key
] = value
564 # Is the property `key` set?
565 fun has_key
(key
: String): Bool do return properties
.has_key
(key
)
568 # Nodes are used to represent entities stored in base.
569 # Apart from properties and relationships (edges),
570 # nodes can also be labeled with zero or more labels.
572 # A label is a `String` that is used to group nodes into sets.
573 # All nodes labeled with the same label belongs to the same set.
574 # A node may be labeled with any number of labels, including none,
575 # making labels an optional addition to the graph.
577 # Creating new nodes:
579 # var client = new Neo4jClient("http://localhost:7474")
581 # var andres = new NeoNode
582 # andres.labels.add "Person"
583 # andres["name"] = "Andres"
585 # client.save_node(andres)
586 # assert andres.is_linked
588 # Get nodes from Neo4j:
590 # var url = andres.url.to_s
591 # var node = client.load_node(url)
592 # assert node["name"] == "Andres"
593 # assert node["age"].to_s.to_i == 22
597 private var internal_labels
: nullable Array[String] = null
598 private var internal_in_edges
: nullable List[NeoEdge] = null
599 private var internal_out_edges
: nullable List[NeoEdge] = null
603 self.internal_labels
= new Array[String]
604 self.internal_in_edges
= new List[NeoEdge]
605 self.internal_out_edges
= new List[NeoEdge]
609 var tpl
= new FlatBuffer
611 tpl
.append
"labels: [{labels.join(", ")}],"
612 tpl
.append
"data: {properties.to_json}"
614 return tpl
.write_to_string
617 # A label is a `String` that is used to group nodes into sets.
618 # A node may be labeled with any number of labels, including none.
619 # All nodes labeled with the same label belongs to the same set.
621 # Many database queries can work with these sets instead of the whole graph,
622 # making queries easier to write and more efficient.
624 # Labels are loaded lazily
625 fun labels
: Array[String] do return internal_labels
or else load_labels
627 private fun load_labels
: Array[String] do
628 var labels
= new Array[String]
629 var res
= neo
.get
("{url.to_s}/labels")
630 if res
isa JsonArray then
631 for val
in res
do labels
.add val
.to_s
633 internal_labels
= labels
637 # Get the list of `NeoEdge` pointing to `self`
639 # Edges are loaded lazily
640 fun in_edges
: List[NeoEdge] do return internal_in_edges
or else load_in_edges
642 private fun load_in_edges
: List[NeoEdge] do
643 var edges
= new List[NeoEdge]
644 var res
= neo
.get
("{url.to_s}/relationships/in").as(JsonArray)
646 edges
.add
(new NeoEdge.from_json
(neo
, obj
.as(JsonObject)))
648 internal_in_edges
= edges
652 # Get the list of `NeoEdge` pointing from `self`
654 # Edges are loaded lazily
655 fun out_edges
: List[NeoEdge] do return internal_out_edges
or else load_out_edges
657 private fun load_out_edges
: List[NeoEdge] do
658 var edges
= new List[NeoEdge]
659 var res
= neo
.get
("{url.to_s}/relationships/out")
660 for obj
in res
.as(JsonArray) do
661 edges
.add
(new NeoEdge.from_json
(neo
, obj
.as(JsonObject)))
663 internal_out_edges
= edges
667 # Get nodes pointed by `self` following a `rel_type` edge
668 fun out_nodes
(rel_type
: String): Array[NeoNode] do
669 var res
= new Array[NeoNode]
670 for edge
in out_edges
do
671 if edge
.rel_type
== rel_type
then res
.add edge
.to
676 # Get nodes pointing to `self` following a `rel_type` edge
677 fun in_nodes
(rel_type
: String): Array[NeoNode] do
678 var res
= new Array[NeoNode]
679 for edge
in in_edges
do
680 if edge
.rel_type
== rel_type
then res
.add edge
.from
686 # A relationship between two nodes.
687 # Relationships between nodes are a key part of a graph database.
688 # They allow for finding related data. Just like nodes, relationships can have properties.
690 # Create a relationship:
692 # var client = new Neo4jClient("http://localhost:7474")
694 # var andres = new NeoNode
695 # andres["name"] = "Andres"
696 # var kate = new NeoNode
697 # kate["name"] = "Kate"
698 # # Create a relationship of type `LOVES`
699 # var loves = new NeoEdge(andres, "LOVES", kate)
700 # client.save_edge(loves)
701 # assert loves.is_linked
703 # Get an edge from DB:
705 # var url = loves.url.to_s
706 # var edge = client.load_edge(url)
707 # assert edge.from["name"].to_s == "Andres"
708 # assert edge.to["name"].to_s == "Kate"
712 private var internal_from
: nullable NeoNode
713 private var internal_to
: nullable NeoNode
714 private var internal_type
: nullable String
715 private var internal_from_url
: nullable String
716 private var internal_to_url
: nullable String
718 init(from
: NeoNode, rel_type
: String, to
: NeoNode) do
719 self.internal_from
= from
720 self.internal_to
= to
721 self.internal_type
= rel_type
724 redef init from_neo
(neo
, url
) do
726 var obj
= neo
.get
(url
).as(JsonObject)
727 self.internal_type
= obj
["type"].to_s
728 self.internal_from_url
= obj
["start"].to_s
729 self.internal_to_url
= obj
["end"].to_s
732 redef init from_json
(neo
, obj
) do
734 self.internal_type
= obj
["type"].to_s
735 self.internal_from_url
= obj
["start"].to_s
736 self.internal_to_url
= obj
["end"].to_s
740 fun from
: NeoNode do return internal_from
or else load_from
742 private fun load_from
: NeoNode do
743 var node
= neo
.load_node
(internal_from_url
.to_s
)
749 fun to
: NeoNode do return internal_to
or else load_to
751 private fun load_to
: NeoNode do
752 var node
= neo
.load_node
(internal_to_url
.to_s
)
758 fun rel_type
: nullable String do return internal_type
760 # Get the JSON body of a REST request that create the relationship.
761 private fun to_rest
: JsonObject do
762 var obj
= new JsonObject
766 obj
["to"] = "\{{to.batch_id.to_s}\}"
768 obj
["type"] = rel_type
769 obj
["data"] = properties
774 # Batches are used to perform multiple operations on the REST API in one cURL request.
775 # This can significantly improve performance for large insert and update operations.
777 # see: http://docs.neo4j.org/chunked/milestone/rest-api-batch-ops.html
779 # This service is transactional.
780 # If any of the operations performed fails (returns a non-2xx HTTP status code),
781 # the transaction will be rolled back and all changes will be undone.
785 # var client = new Neo4jClient("http://localhost:7474")
787 # var node1 = new NeoNode
788 # var node2 = new NeoNode
789 # var edge = new NeoEdge(node1, "TO", node2)
791 # var batch = new NeoBatch(client)
792 # batch.save_node(node1)
793 # batch.save_node(node2)
794 # batch.save_edge(edge)
797 # assert node1.is_linked
798 # assert node2.is_linked
799 # assert edge.is_linked
802 # Neo4j client connector
803 var client
: Neo4jClient
805 # Jobs to perform in this batch
807 # The batch service expects an array of job descriptions as input,
808 # each job description describing an action to be performed via the normal server API.
809 var jobs
= new HashMap[Int, NeoJob]
811 # Append a new job to the batch in JSON Format
813 fun new_job
(nentity
: NeoEntity): NeoJob do
815 var job
= new NeoJob(id
, nentity
)
820 # Load a node in batch mode also load labels, data and edges
821 fun load_node
(node
: NeoNode) do
822 var job
= new_job
(node
)
823 job
.action
= load_node_data_action
825 if node
.id
!= null then
826 job
.to
= "/node/{node.id.to_s}"
828 job
.to
= "\{{node.batch_id.to_s}\}"
831 job
.action
= load_node_labels_action
833 if node
.id
!= null then
834 job
.to
= "/node/{node.id.to_s}/labels"
836 job
.to
= "\{{node.batch_id.to_s}\}/labels"
840 # Load in and out edges into node
841 fun load_node_edges
(node
: NeoNode) do
842 var job
= new_job
(node
)
843 job
.action
= load_node_in_edges_action
845 if node
.id
!= null then
846 job
.to
= "/node/{node.id.to_s}/relationships/in"
848 job
.to
= "\{{node.batch_id.to_s}\}/relationships/in"
851 job
.action
= load_node_out_edges_action
853 if node
.id
!= null then
854 job
.to
= "/node/{node.id.to_s}/relationships/out"
856 job
.to
= "\{{node.batch_id.to_s}\}/relationships/out"
860 # Create a `NeoNode` or a `NeoEdge` in batch mode.
861 fun save_entity
(nentity
: NeoEntity) do
862 if nentity
isa NeoNode then
864 else if nentity
isa NeoEdge then
869 # Create a node in batch mode also create labels and edges
870 fun save_node
(node
: NeoNode) do
871 if node
.id
!= null or node
.batch_id
!= null then return
873 var job
= new_job
(node
)
874 node
.batch_id
= job
.id
875 job
.action
= create_node_action
878 job
.body
= node
.properties
882 job
.to
= "\{{node.batch_id.to_s}\}/labels"
883 job
.body
= new JsonArray.from
(node
.labels
)
885 #save_edges(node.out_edges)
888 # Create multiple nodes
889 # also create labels and edges
890 fun save_nodes
(nodes
: Collection[NeoNode]) do for node
in nodes
do save_node
(node
)
893 # nodes `edge.from` and `edge.to` will be created if not in base
894 fun save_edge
(edge
: NeoEdge) do
895 if edge
.id
!= null or edge
.batch_id
!= null then return
900 var job
= new_job
(edge
)
901 edge
.batch_id
= job
.id
902 job
.action
= create_edge_action
904 if edge
.from
.id
!= null then
905 job
.to
= "/node/{edge.from.id.to_s}/relationships"
907 job
.to
= "\{{edge.from.batch_id.to_s}\}/relationships"
909 job
.body
= edge
.to_rest
912 # Create multiple edges
913 fun save_edges
(edges
: Collection[NeoEdge]) do for edge
in edges
do save_edge
(edge
)
915 # Execute the batch and update local nodes
916 fun execute
: List[NeoError] do
917 var request
= new JsonPOST(client
.batch_url
, client
.curl
)
918 # request.headers["X-Stream"] = "true"
919 var json_jobs
= new JsonArray
920 for job
in jobs
.values
do json_jobs
.add job
.to_rest
921 request
.data
= json_jobs
922 var response
= request
.execute
923 var res
= client
.parse_response
(response
)
924 return finalize_batch
(res
)
927 # Associate data from response in original nodes and edges
928 private fun finalize_batch
(response
: Jsonable): List[NeoError] do
929 var errors
= new List[NeoError]
930 if not response
isa JsonArray then
931 errors
.add
(new NeoError("Unexpected batch response format.", "Neo4jError"))
934 # print " {res.length} jobs executed"
935 for res
in response
do
936 if not res
isa JsonObject then
937 errors
.add
(new NeoError("Unexpected job format in batch response.", "Neo4jError"))
940 var id
= res
["id"].as(Int)
942 if job
.action
== create_node_action
then
943 var node
= job
.entity
.as(NeoNode)
945 node
.url
= res
["location"].to_s
946 else if job
.action
== create_edge_action
then
947 var edge
= job
.entity
.as(NeoEdge)
949 edge
.url
= res
["location"].to_s
950 else if job
.action
== load_node_data_action
then
951 var node
= job
.entity
.as(NeoNode)
952 node
.internal_properties
= res
["body"].as(JsonObject)["data"].as(JsonObject)
953 else if job
.action
== load_node_labels_action
then
954 var node
= job
.entity
.as(NeoNode)
955 var labels
= new Array[String]
956 for l
in res
["body"].as(JsonArray) do labels
.add l
.to_s
957 node
.internal_labels
= labels
958 else if job
.action
== load_node_in_edges_action
then
959 var node
= job
.entity
.as(NeoNode)
960 var edges
= res
["body"].as(JsonArray)
961 node
.internal_in_edges
= new List[NeoEdge]
963 node
.internal_in_edges
.add client
.load_edge
(edge
.as(JsonObject)["self"].to_s
)
965 else if job
.action
== load_node_out_edges_action
then
966 var node
= job
.entity
.as(NeoNode)
967 var edges
= res
["body"].as(JsonArray)
968 node
.internal_out_edges
= new List[NeoEdge]
970 node
.internal_out_edges
.add client
.load_edge
(edge
.as(JsonObject)["self"].to_s
)
978 # TODO replace with enum
980 private fun create_node_action
: Int do return 1
981 private fun create_edge_action
: Int do return 2
982 private fun load_node_data_action
: Int do return 3
983 private fun load_node_labels_action
: Int do return 4
984 private fun load_node_in_edges_action
: Int do return 5
985 private fun load_node_out_edges_action
: Int do return 6
988 # A job that can be executed in a `NeoBatch`
989 # This is a representation of a neo job in JSON Format
991 # Each job description should contain a `to` attribute, with a value relative to the data API root
992 # (so http://localhost:7474/db/data/node becomes just /node), and a `method` attribute containing
995 # Optionally you may provide a `body` attribute, and an `id` attribute to help you keep track
996 # of responses, although responses are guaranteed to be returned in the same order the job
997 # descriptions are received.
1001 # Entity targeted by the job
1002 var entity
: NeoEntity
1004 init(id
: Int, entity
: NeoEntity) do
1006 self.entity
= entity
1009 # What kind of action do the job
1010 # used to attach responses to original Neo objets
1011 private var action
: nullable Int = null
1013 # Job HTTP method: `GET`, `POST`, `PUT`, `DELETE`...
1015 # Job service target: `/node`, `/labels` etc...
1017 # Body to send with the job service request
1018 var body
: nullable Jsonable = null
1021 fun to_rest
: JsonObject do
1022 var job
= new JsonObject
1024 job
["method"] = method
1026 if not body
== null then