asami-loom

This library extends Asami in-memory graphs to Loom.

By requiring asami-loom.index, then the asami.index.IndexGraph graphs are extended to:

• loom.graph.Graph
• loom.graph.EditableGraph
• loom.graph.DiGraph

By requiring asami-loom.multi-graph, then the asami.multi-graph.MultiGraph graphs are extended to:

• loom.graph.Graph
• loom.graph.EditableGraph
• loom.graph.DiGraph
• loom.graph.WeightedGraph

By requiring asami-loom.label, then both the asami.index.IndexGraph and asami.multi-graph.MultiGraph graphs get extended to:

• loom.label.LabeledGraph

Usage

Requiring one of the above namespaces in any namespace that uses Asami in-memory graphs will automatically apply the extensions. Loom can use the graphs with the standard APIs.

Example

Configuring Asami Loom can be done by requiring the appropriate name spaces. Then just load data into Asami as usual.

Note: Some of this API will change soon to simplify. Specifically, the use of the Naga Storage API will be dropped. This means that naga.store won't be needed, as the graph won't need to be extracted from the store object.

(require '[asami.core :as d :refer [create-database connect transact db q]])

(create-database "asami:mem://music")
(def conn (connect "asami:mem://music"))

(def data
 [{:db/ident "paul"
   :artist/name "Paul McCartney"}
  {:db/ident "george"
   :artist/name "George Harrison"}
  {:db/ident "john"
   :artist/name "John Lennon"}
  {:release/artists {:db/ident "paul"}
   :release/name "My Sweet Lord"}
  {:release/artists {:db/ident "george"}
   :release/name "Electronic Sound"}
  {:release/artists {:db/ident "george"}
   :release/name "Give Me Love (Give Me Peace on Earth)"}
  {:release/artists {:db/ident "george"}
   :release/name "All Things Must Pass"}
  {:release/artists {:db/ident "john"}
   :release/name "Imagine"}])

(transact conn {:tx-data data})
(def graph (d/graph (db conn)))

The entity IDs created with nn above are represented as keywords with the namespace "mem". Also, edges are typically keywords, but can also be strings. With these assumptions in mind, we can use the following definitions to get labels for edges or nodes.

(defn edge-label
  [g s d]
  (str (q '[:find ?edge . :in $ ?a ?b :where (or [?a ?edge ?b] [?b ?edge ?a])] g s d)))

(defn node-label
  [g n]
  (let [id (q [:find '?id '. :where [n :db/ident '?id]] g)]
    (cond id (str id)
          (and (keyword? n) (= (namespace n) "tg")) (str ":" (name n))
          :default (str n))))

With this configuration set up, the Loom display function can be used to create a graphical view.

(require '[asami-loom.index])
(require '[asami-loom.label])
(require '[loom.io :as loom-io])

(loom-io/view graph :fmt :pdf :alg :sfdp :edge-label (partial edge-label graph) :node-label (partial node-label graph))

View Parameters

Valid algorithms are:

• :dot
• :neato
• :fdp
• :sfdp
• :twopi
• :circo

Valid Formats are:

• :png
• :ps
• :pdf
• :svg

Loom launches the system default viewers for these file types.

License

Copyright © 2019-2020 Cisco Systems

Copyright © 2022 Paula Gearon

This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.

This Source Code may also be made available under the following Secondary Licenses when the conditions for such availability set forth in the Eclipse Public License, v. 2.0 are satisfied: GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version, with the GNU Classpath Exception which is available at https://www.gnu.org/software/classpath/license.html.