[FEATURE] RuntimeContext supports more accurate type definition #4467
Description
Problem Statement
The type definition of RuntimeContext is type-safe and accurate when set(). However, it is safe but inaccurate when get(), which is very inconvenient to use.
For example:
type MyRuntimeContext = {
name: string;
age: number;
};
const runtimeContext = new RuntimeContext<MyRuntimeContext>();
runtimeContext.set('name', 'John');
runtimeContext.set('age', 20);
// The following get('age') infers string|number, but expects number
const age = runtimeContext.get('age');Proposed Solution
The following is the type redeclare I used in the project:
declare module '@mastra/core/runtime-context' {
export class RuntimeContext<Values extends Record<string, any> = Record<string, any>> {
private registry: Map<string, any>;
constructor(iterable?: Iterable<{ [K in keyof Values]: [K, Values[K]] }[keyof Values]>);
set<K extends keyof Values>(key: K, value: Values[K]): void;
set(key: string, value: unknown): void;
get<K extends keyof Values>(key: K): Values[K];
get(key: string): unknown;
has(key: string): boolean;
delete(key: string): boolean;
clear(): void;
keys(): IterableIterator<keyof Values>;
values(): IterableIterator<Values[keyof Values]>;
entries(): IterableIterator<{ [K in keyof Values]: [K, Values[K]] }[keyof Values]>;
forEach<K extends keyof Values>(callbackfn: (value: Values[K], key: K, map: Map<string, any>) => void): void;
size(): number;
}
}Component
Workflows
Alternatives Considered
No response
Example Use Case
for (const [key, value] of runtimeContext.entries()) {
if (key === 'age') {
// value is correctly inferred as number
} else {
// value is correctly inferred as string
}
}Additional Context
No response
Verification
- I have searched the existing issues to make sure this is not a duplicate
- I have provided sufficient context for the team to understand the request