hash-graph-nodes v1.0.7

hash-graph-nodes

hash-graph-nodes is a library that assignes a uniq hash to all the nodes in the graph. The hash is deterministic and stable, the same input will always produce the same output. The hash reflects the content of a node and the hash of its children. This means that if a node changes content, all ancestors will get a new hash. This is useful for cache invalidation.

The special feature of hash-graph is that it can hash graphs that have cycles. This feature is inspired from this article.

Usage

const { getNodeHashes } = require("hash-graph-nodes");

const graph = {
  nodes: [
    { contentHash: "foo", id: 1 },
    { contentHash: "bar", id: 2 },
    { contentHash: "baz", id: 3 },
  ],
  links: [
    { source: 1, target: 2 },
    { source: 2, target: 3 },
    { source: 3, target: 2 }, // Graph cycle!
  ],
};

const nodeHashes = getNodeHashes(graph);

const hash1 = nodeHashes.get(1);
const hash2 = nodeHashes.get(2);
const hash3 = nodeHashes.get(3);