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@loaders.gl/graphs

Framework-independent loaders for GraphML and Graphviz DOT documents.

GraphML loader​

GraphMLLoader reads the first graph in a GraphML 1.0 document.

import {load} from '@loaders.gl/core';
import {GraphMLLoader} from '@loaders.gl/graphs';

const graph = await load('network.graphml', GraphMLLoader);

Pass GraphMLLoader to parseSync from @loaders.gl/core for synchronous parsing. The direct parser subpath also exports GraphMLLoaderWithParser from @loaders.gl/graphs/graphml-loader.

The result is GraphData with shape: 'plain-graph-data', nodes, and edges. Nodes have id, optional label, and optional attributes. Edges additionally have sourceId, targetId, and directed. This shape is compatible with createGraphFromData in @deck.gl-community/graph-layers.

Supported constructs include node and edge identifiers, generated IDs for unnamed edges, edgedefault and per-edge direction overrides, node/edge/all keys, typed data and defaults, unknown data keys, and namespace-prefixed elements. Numeric and boolean keys become JavaScript values; other values remain strings. Nested XML data becomes a JSON string.

Only the first graph is returned. Nested graphs, hyperedges, ports, and graph-level data are ignored. Nodes without IDs and edges without endpoints are skipped. This is a permissive parser, not a GraphML schema validator. Long integers use JavaScript numbers and may lose precision outside the safe integer range.

DOT loader​

import {load} from '@loaders.gl/core';
import {DOTLoader} from '@loaders.gl/graphs';

const graph = await load('network.dot', DOTLoader);

Pass DOTLoader to parseSync for synchronous text or UTF-8 ArrayBuffer parsing. The direct parser subpath also exports DOTLoaderWithParser from @loaders.gl/graphs/dot-loader. DOTLoader recognizes .dot and .gv files.

The loader returns the same plain GraphData node/edge shape as GraphML, plus typed DOT metadata: graph ID, direction, strictness, graph attributes, and subgraph descriptors. Identifiers remain strings, including numeric-looking IDs. Unquoted numeric attributes become numbers; quoted attributes remain strings. Node and edge label attributes are also exposed as record labels.

Supported syntax includes graph and digraph, strict graphs with parallel-edge coalescing, implicit nodes, chained edges, repeated attribute lists, scoped node/edge defaults, graph attribute assignments, nested named and anonymous subgraphs, comments, quoted identifiers, and balanced HTML-like labels. Node and edge attributes include subgraph membership descriptors. Reopening a named subgraph retains its attributes and node/edge defaults; anonymous subgraph identifiers remain distinct from explicit names. An edge id, Id, or ID attribute supplies its ID; otherwise the loader generates an ID from its endpoints and a counter. dir=none marks an edge as undirected; other dir strings mark it as directed.

This is a parser for the supported DOT subset, not a Graphviz renderer. Node ports, subgraph endpoints in edge statements, and concatenated quoted strings are unsupported. Port syntax is rejected; identifiers containing colons must be quoted. Truncated input, trailing content, and edge operators inconsistent with the graph declaration are rejected.