add ignore root folder setting

packages/foam-vscode/package.json

@@ -283,6 +283,13 @@
           ],
           "description": "Specifies the list of globs that will be ignored by Foam (e.g. they will not be considered when creating the graph). To ignore the all the content of a given folder, use `<folderName>/**/*`"
         },
+        "foam.rootFolders.ignore": {
+          "type": [
+            "array"
+          ],
+          "default": [],
+          "description": "Specifies the list of folders that will be ignored by Foam (e.g. they will not be considered when creating the graph). This is useful in multi-root workspaces."
+        },
         "foam.logging.level": {
           "type": "string",
           "default": "info",

packages/foam-vscode/src/extension.ts

@@ -7,7 +7,10 @@ import { Logger } from './core/utils/log';
 
 import { features } from './features';
 import { VsCodeOutputLogger, exposeLogger } from './services/logging';
-import { getIgnoredFilesSetting } from './settings';
+import {
+  getIgnoredFilesSetting,
+  getIgnoredRootFoldersSetting,
+} from './settings';
 import { fromVsCodeUri, toVsCodeUri } from './utils/vsc-utils';
 import { AttachmentResourceProvider } from './core/services/attachment-provider';
 import { VsCodeWatcher } from './services/watcher';
@@ -26,8 +29,11 @@ export async function activate(context: ExtensionContext) {
     const readFile = async (uri: URI) =>
       (await workspace.fs.readFile(toVsCodeUri(uri))).toString();
     const dataStore = new FileDataStore(readFile);
+    const ignoredRoots = getIgnoredRootFoldersSetting();
     const matcher = new Matcher(
-      workspace.workspaceFolders.map(dir => fromVsCodeUri(dir.uri)),
+      workspace.workspaceFolders
+        .filter(dir => !ignoredRoots.includes(dir.name))
+        .map(dir => fromVsCodeUri(dir.uri)),
       ['**/*'],
       getIgnoredFilesSetting().map(g => g.toString())
     );

packages/foam-vscode/src/settings.ts

@@ -24,6 +24,11 @@ export function getIgnoredFilesSetting(): GlobPattern[] {
   ];
 }
 
+/** Retrieve the list of root folders to ignore. */
+export function getIgnoredRootFoldersSetting(): string[] {
+  return [...workspace.getConfiguration().get('foam.rootFolders.ignore', [])];
+}
+
 /** Retrieves the maximum length for a Graph node title. */
 export function getTitleMaxLength(): number {
   return workspace.getConfiguration('foam.graph').get('titleMaxLength');