Graphology TypeScript Types

Common errors

• TS2307: Cannot find module 'graphology-types' or its corresponding type declarations.

  cause The `graphology-types` package has not been installed or TypeScript cannot locate its declaration files.
  fix Run `npm install graphology-types` or `yarn add graphology-types`. Ensure `tsconfig.json` includes `node_modules/@types` in its `typeRoots` or that the package is correctly referenced.

• Property 'xyz' does not exist on type 'NodeAttributes'.

  cause Attempting to access a node or edge attribute that has not been explicitly defined in the custom `NodeAttributes` or `EdgeAttributes` interface.
  fix Extend `NodeAttributes` or `EdgeAttributes` with your custom properties, e.g., `interface MyNodeAttrs extends NodeAttributes { xyz: string; }` and use `Graph<MyNodeAttrs>`.

• Argument of type 'number' is not assignable to parameter of type 'string'.

  cause A type mismatch occurs when setting or retrieving an attribute, where the value provided does not match the type defined in the custom `NodeAttributes` or `EdgeAttributes` interface.
  fix Ensure that the values passed to `addNode`, `setNodeAttribute`, etc., strictly conform to the types defined in your custom attribute interfaces.

• Module 'graphology-types' has no exported member 'X'. Did you mean 'Y'?

  cause An incorrect named import was used, or the symbol 'X' does not exist in the `graphology-types` package.
  fix Verify the exact name of the type or interface you are trying to import from the `graphology-types` documentation or its `d.ts` files. Ensure you are using named imports for interfaces and types.

Warnings

• breaking Version `0.26.0` introduces ESM support across the `graphology` ecosystem. While `graphology-types` primarily provides declaration files, this change in the underlying library may impact how `graphology` is imported and subsequently how types are resolved in mixed CJS/ESM projects.
  Fix: Ensure your project's module resolution (e.g., `tsconfig.json` `moduleResolution`) is configured correctly for 'NodeNext' or 'Bundler' if using ESM, and update `graphology` to a compatible version if facing runtime import issues.
• breaking The `obliterator` dependency was removed in version `0.26.0`. While this is primarily an internal change, if any type definitions from `obliterator` were inadvertently exposed or relied upon in custom extensions, their removal could lead to type errors.
  Fix: Review custom type definitions or interfaces that might have implicitly relied on `obliterator` types. Update code to use standard JavaScript iteration protocols or `graphology`'s native iteration methods.
• breaking Version `0.24.0` removed undocumented methods `#.upgradeToMixed` and `#.upgradeToMulti` from the `Graph` class. Although undocumented, if these methods were used, their removal will result in type and runtime errors.
  Fix: Refactor code to use supported graph conversion methods or ensure only documented APIs are accessed. Consult the `graphology` documentation for official upgrade paths.
• breaking Version `0.24.0` also includes 'Dropping some irrelevant arities for edge attribute' setters/getters. This could lead to type mismatches if custom attribute functions or specific parameter counts were expected when interacting with edge attributes.
  Fix: Review usage of `setEdgeAttribute`, `getEdgeAttribute`, etc., and ensure they conform to the updated (and officially documented) function signatures for attribute handling.

Install

• npm install graphology-types npm
• yarn add graphology-types yarn
• pnpm add graphology-types pnpm

Imports

• Graph
  wrong:

  import Graph from 'graphology-types';

  correct:

  import { Graph } from 'graphology-types';

  Imports the Graph *interface* for type declarations, not the Graph class itself. The actual Graph class is imported from 'graphology'.
• NodeAttributes

  import { NodeAttributes } from 'graphology-types';

  Standard import for the base interface representing node attributes. Extend this interface for custom attribute types.
• EdgeAttributes

  import { EdgeAttributes } from 'graphology-types';

  Standard import for the base interface representing edge attributes. Extend this interface for custom attribute types.

Quickstart

Demonstrates how to define and use a `graphology` graph with custom type-safe node and edge attributes using `graphology-types`.

import Graph from 'graphology';
import { Graph as GraphType, NodeAttributes, EdgeAttributes } from 'graphology-types';

// Define custom interfaces for node and edge attributes
interface MyNodeAttributes extends NodeAttributes {
  name: string;
  weight?: number;
}

interface MyEdgeAttributes extends EdgeAttributes {
  type: 'friend' | 'family';
  since: Date;
}

// Instantiate a graph with specific types for node and edge attributes
const graph: GraphType<MyNodeAttributes, MyEdgeAttributes> = new Graph<MyNodeAttributes, MyEdgeAttributes>();

// Add nodes with type-checked attributes
graph.addNode('john', { name: 'John Doe', weight: 80 });
graph.addNode('jane', { name: 'Jane Smith' });

// Add edges with type-checked attributes
graph.addEdge('john', 'jane', { type: 'friend', since: new Date('2020-01-01') });

// Access attributes with type inference
const johnsName: string = graph.getNodeAttribute('john', 'name');
const edgeType: 'friend' | 'family' = graph.getEdgeAttribute('john', 'jane', 'type');

console.log(`John's name: ${johnsName}`);
console.log(`Relationship type: ${edgeType}`);
console.log(`Graph order: ${graph.order}`);
console.log(`Graph size: ${graph.size}`);