src/Gargantext/Core/Viz/Graph/GEXF.hs

   1 {-|
   2 Module      : Gargantext.Core.Viz.Graph
   3 Description :
   4 Copyright   : (c) CNRS, 2017-Present
   5 License     : AGPL + CECILL v3
   6 Maintainer  : team@gargantext.org
   7 Stability   : experimental
   8 Portability : POSIX
   9
  10 -}
  11
  12
  13 {-# OPTIONS_GHC -fno-warn-orphans #-}
  14
  15 {-# LANGUAGE OverloadedLists   #-}   -- allows to write Map and HashMap as lists
  16 {-# LANGUAGE TypeOperators     #-}
  17
  18 module Gargantext.Core.Viz.Graph.GEXF
  19   where
  20
  21 import Gargantext.Prelude
  22 import Gargantext.Core.Viz.Graph
  23 import qualified Data.HashMap.Lazy as HashMap
  24 import qualified Gargantext.Prelude as P
  25 import qualified Gargantext.Core.Viz.Graph as G
  26 import qualified Xmlbf as Xmlbf
  27 import Prelude (error)
  28
  29 -- Converts to GEXF format
  30 -- See https://gephi.org/gexf/format/
  31 instance Xmlbf.ToXml Graph where
  32   toXml (Graph { _graph_nodes = graphNodes
  33                 , _graph_edges = graphEdges }) = root graphNodes graphEdges
  34     where
  35       root :: [G.Node] -> [G.Edge] -> [Xmlbf.Node]
  36       root gn ge =
  37         Xmlbf.element "gexf" params $ meta <> (graph gn ge)
  38         where
  39           params = HashMap.fromList [ ("xmlns", "http://www.gexf.net/1.2draft")
  40                                     , ("version", "1.2") ]
  41       meta = Xmlbf.element "meta" params $ creator <> desc
  42         where
  43           params = HashMap.fromList [ ("lastmodifieddate", "2020-03-13") ]
  44       creator = Xmlbf.element "creator" HashMap.empty $ Xmlbf.text "Gargantext.org"
  45       desc = Xmlbf.element "description" HashMap.empty $ Xmlbf.text "Gargantext gexf file"
  46       graph :: [G.Node] -> [G.Edge] -> [Xmlbf.Node]
  47       graph gn ge = Xmlbf.element "graph" params $ (nodes gn) <> (edges ge)
  48         where
  49           params = HashMap.fromList [ ("mode", "static")
  50                                     , ("defaultedgetype", "directed") ]
  51       nodes :: [G.Node] -> [Xmlbf.Node]
  52       nodes gn = Xmlbf.element "nodes" HashMap.empty $ P.concatMap node' gn
  53
  54       node' :: G.Node -> [Xmlbf.Node]
  55       node' (G.Node { node_id = nId, node_label = l, node_size = w}) =
  56         Xmlbf.element "node" params []
  57         where
  58           params = HashMap.fromList [ ("id", nId)
  59                                     , ("label", l)
  60                                     , ("size", (cs . show) w)]
  61       edges :: [G.Edge] -> [Xmlbf.Node]
  62       edges gn = Xmlbf.element "edges" HashMap.empty $ P.concatMap edge gn
  63       edge :: G.Edge -> [Xmlbf.Node]
  64       edge (G.Edge { edge_id = eId, edge_source = es, edge_target = et }) =
  65         Xmlbf.element "edge" params []
  66         where
  67           params = HashMap.fromList [ ("id", eId)
  68                                     , ("source", es)
  69                                     , ("target", et) ]
  70
  71 -- just to be able to derive a client for the entire gargantext API,
  72 -- we however want to avoid sollicitating this instance
  73 instance Xmlbf.FromXml Graph where
  74   fromXml = error "FromXml Graph: not defined, just a placeholder"