use canonical direction

[rjawesome]

Uses canonical direction instead of query direction as stated by this issue. Depends on this PR on biolink-model.js

Example query w/ query direction of treated_by (not canonical):

{
    "message": {
        "query_graph": {
            "nodes": {
                "n0": {
                    "ids": ["MONDO:0018956"]
                },
                "n1": {
                    "ids": ["PUBCHEM.COMPOUND:84029"]
                }
            },
            "edges": {
                "e01": {
                    "subject": "n0",
                    "object": "n1"
                }
            }
        }
    }
}

Reponse (the knowledge_graph edge):

                "44da256a3888bc5cbd2da115e64f92f4": {
                    "predicate": "biolink:treats",
                    "subject": "PUBCHEM.COMPOUND:84029",
                    "object": "MONDO:0018956",
                    

[codecov]

Codecov Report

Merging #117 (f41c9af) into main (984f68e) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #117   +/-   ##
=======================================
  Coverage   57.80%   57.80%           
=======================================
  Files          25       25           
  Lines        2057     2057           
=======================================
  Hits         1189     1189           
  Misses        868      868           

Impacted Files	Coverage Δ
src/biolink.js	100.00% <100.00%> (ø)
src/graph/graph.js	96.42% <100.00%> (ø)
src/index.js	34.54% <100.00%> (ø)

📣 Codecov can now indicate which changes are the most critical in Pull Requests. Learn more

[tokebe]

Looks fine to me, tested with another query:

curl --request POST \
  --url http://localhost:3000/v1/query \
  --header 'Content-Type: application/json' \
  --data '{
  "message": {
    "query_graph": {
      "nodes": {
        "n02": {
          "categories": [
            "biolink:Disease"
          ],
          "ids": ["MONDO:0005377"]
        },
        "n01": {
          "categories": [
            "biolink:ChemicalEntity"
          ]
        }
      },
      "edges": {
        "e01": {
          "subject": "n02",
          "object": "n01",
          "predicates": ["biolink:treated_by"]
        }
      }
    }
  }
}'

Tagging @colleenXu for a quick confirmation that everything looks fine

[tokebe]

Original issue not planned.