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HTTP Interface for Edges

@NAVIGATE_RestEdge @EMBEDTOC{RestEdgeTOC}

This is an introduction to ArangoDB's REST interface for edges.

ArangoDB offers also some graph functionality. A graph consists of nodes, edges and properties. ArangoDB stores the information how the nodes relate to each other aside from the properties.

A graph data model always consists of two collections: the relations between the nodes in the graphs are stored in an "edges collection", the nodes in the graph are stored in documents in regular collections.

Example:

the "edge" collection stores the information that a company's reception is sub-unit to the services unit and the services unit is sub-unit to the CEO. You would express this relationship with the to and _to attributes.
the "normal" collection stores all the properties about the reception, e.g. that 20 people are working there and the room number etc.
_from is the document handle of the linked vertex (incoming relation),
_to is the document handle of the linked vertex (outgoing relation).

Documents, Identifiers, Handles

@copydoc GlossaryEdge

Address and ETag of an Edge

All documents in ArangoDB have a document handle. This handle uniquely identifies a document. Any document can be retrieved using its unique URI:

http://server:port/_api/document/<document-handle>

Edges are a special variation of documents, and to work with edges, the above URL format changes to:

http://server:port/_api/edge/<document-handle>

For example, assumed that the document handle, which is stored in the _id attribute of the edge, is demo/362549736, then the URL of that edge is:

http://localhost:8529/_api/edge/demo/362549736

The above URL scheme does not specify a database name explicitly, so the default database will be used. To explicitly specify the database context, use the following URL schema:

http://server:port/_db/<database-name>/_api/edge/<document-handle>

Example:

http://localhost:8529/_db/mydb/_api/edge/demo/362549736

Note that the following examples use the short URL format for brevity.

Working with Edges using REST

@anchor RestEdgeRead @RESTHEADER{GET /_api/edge,reads an edge}

@REST{GET /_api/edge/@FA{document-handle}}