Optionally render AssetGraph to GraphViz dot format

packages/core/core/src/requests/BundleGraphRequest.js

@@ -15,6 +15,7 @@ import type {
 } from '../types';
 import type {ConfigAndCachePath} from './AtlaspackConfigRequest';
 
+import fs from 'fs';
 import invariant from 'assert';
 import assert from 'assert';
 import nullthrows from 'nullthrows';
@@ -57,6 +58,11 @@ import createAssetGraphRequestJS from './AssetGraphRequest';
 import {createAssetGraphRequestRust} from './AssetGraphRequestRust';
 import {tracer, PluginTracer} from '@atlaspack/profiler';
 import {requestTypes} from '../RequestTracker';
+import {
+  assetGraphToDot,
+  getDebugAssetGraphDotPath,
+  getDebugAssetGraphDotOptions,
+} from './asset-graph-dot';
 
 type BundleGraphRequestInput = {|
   requestedAssetIds: Set<string>,
@@ -119,6 +125,15 @@ export default function createBundleGraphRequest(
         },
       );
 
+      let debugAssetGraphDotPath = getDebugAssetGraphDotPath();
+      if (debugAssetGraphDotPath !== null) {
+        await fs.promises.writeFile(
+          debugAssetGraphDotPath,
+          assetGraphToDot(assetGraph, getDebugAssetGraphDotOptions()),
+          'utf8',
+        );
+      }
+
       // if (input.rustAtlaspack && process.env.NATIVE_COMPARE === 'true') {
       //   let {assetGraph: jsAssetGraph} = await api.runRequest(
       //     createAssetGraphRequestJS({

packages/core/core/src/requests/asset-graph-dot.js

@@ -0,0 +1,144 @@
+// @flow
+import path from 'path';
+
+import type {AssetGraphNode} from '../types';
+import AssetGraph from '../AssetGraph';
+
+export type AssetGraphToDotOptions = {
+  style?: boolean,
+  sort?: boolean,
+  ...
+};
+
+/** @description Renders AssetGraph into GraphViz Dot format */
+export function assetGraphToDot(
+  assetGraph: AssetGraph,
+  {sort = false, style = true}: AssetGraphToDotOptions = {},
+): string {
+  const edges = [];
+  const nodeStyles: {[key: string]: string} = {};
+
+  assetGraph.traverse((nodeId) => {
+    let node: AssetGraphNode | null = assetGraph.getNode(nodeId) ?? null;
+    if (!node) return;
+
+    const fromIds = assetGraph.getNodeIdsConnectedTo(nodeId);
+
+    for (const fromId of fromIds) {
+      let fromNode: AssetGraphNode | null = assetGraph.getNode(fromId) ?? null;
+      if (!fromNode) throw new Error('No Node');
+      const edgeStyle = getEdgeStyle(node);
+      const nodeStyle = getNodeStyle(node);
+
+      let entry = `"${getNodeName(fromNode)}" -> "${getNodeName(node)}"`;
+      if (edgeStyle) {
+        entry += ` [${edgeStyle}]`;
+      }
+
+      if (nodeStyle) {
+        nodeStyles[getNodeName(node)] = nodeStyle;
+      }
+
+      edges.push(entry);
+    }
+  });
+
+  // $FlowFixMe
+  const nodeStylesList: Array<[string, string]> = Object.entries(nodeStyles);
+  if (sort) {
+    edges.sort();
+    nodeStylesList.sort();
+  }
+
+  let digraph = `digraph {\n\tnode [shape=rectangle]\n`;
+  if (style) {
+    digraph += nodeStylesList
+      .map(([node, style]) => `\t"${node}" [${style}]\n`)
+      .join('');
+  }
+  digraph += edges.map((v) => `\t${v}\n`).join('');
+  digraph += `}\n`;
+  return digraph;
+}
+
+export function getDebugAssetGraphDotPath(): string | null {
+  let debugAssetGraphDot = process.env.DEBUG_ASSET_GRAPH_DOT;
+  if (debugAssetGraphDot === undefined || debugAssetGraphDot === '') {
+    return null;
+  }
+  if (!path.isAbsolute(debugAssetGraphDot)) {
+    debugAssetGraphDot = path.join(process.cwd(), debugAssetGraphDot);
+  }
+  return debugAssetGraphDot;
+}
+
+export function getDebugAssetGraphDotOptions(): AssetGraphToDotOptions {
+  const options: AssetGraphToDotOptions = {};
+
+  let style = process.env.DEBUG_ASSET_GRAPH_DOT_STYLE;
+  if (style !== undefined) {
+    options.style = style === 'true';
+  }
+
+  let sort = process.env.DEBUG_ASSET_GRAPH_DOT_SORT;
+  if (sort !== undefined) {
+    options.sort = sort === 'true';
+  }
+
+  return options;
+}
+
+function fromCwd(input: string): string {
+  return path.relative(process.cwd(), input);
+}
+
+function getNodeName(node: AssetGraphNode): string {
+  if (node.type === 'asset_group') {
+    // $FlowFixMe
+    return [`asset_group`, node.id, fromCwd(node.value.filePath)].join('\\n');
+  } else if (node.type === 'asset') {
+    // $FlowFixMe
+    return [`asset`, node.id, fromCwd(node.value.filePath)].join('\\n');
+  } else if (node.type === 'dependency') {
+    return [`dependency`, node.id, node.value.specifier].join('\\n');
+  } else if (node.type === 'entry_specifier') {
+    // $FlowFixMe
+    return [`entry_specifier`, node.value].join('\\n');
+  } else if (node.type === 'entry_file') {
+    // $FlowFixMe
+    return [`entry_file`, fromCwd(node.value.filePath)].join('\\n');
+  }
+  return 'ROOT';
+}
+
+function getEdgeStyle(node: AssetGraphNode): string {
+  if (node.type === 'asset_group') {
+    return ``;
+  } else if (node.type === 'asset') {
+    return ``;
+  } else if (node.type === 'dependency') {
+    if (node.value.priority === 2) {
+      return `style="dashed"`;
+    }
+  } else if (node.type === 'entry_specifier') {
+    return ``;
+  } else if (node.type === 'entry_file') {
+    return ``;
+  }
+  return '';
+}
+
+function getNodeStyle(node: AssetGraphNode): string {
+  if (node.type === 'asset_group') {
+    return `fillcolor="#E8F5E9", style="filled"`;
+  } else if (node.type === 'asset') {
+    return `fillcolor="#DCEDC8", style="filled"`;
+  } else if (node.type === 'dependency') {
+    return `fillcolor="#BBDEFB", style="filled"`;
+  } else if (node.type === 'entry_specifier') {
+    return `fillcolor="#FFF9C4", style="filled"`;
+  } else if (node.type === 'entry_file') {
+    return `fillcolor="#FFE0B2", style="filled"`;
+  }
+  return '';
+}