feat(core): add ability to define the agent context type (#350)

* feat(core): ability to define agent context type
* test(core): test that context type is optional (compile time)

packages/core/src/__tests__/agent.test.ts

@@ -1,5 +1,6 @@
-import { Agent } from '../agent'
+import { Agent, createAgent } from '../agent'
 import { IAgentPlugin } from '../types/IAgent'
+import { IResolver } from '../types/IResolver'
 
 describe('core agent', () => {
   it('should use plugin methods', async () => {
@@ -97,7 +98,33 @@ describe('core agent', () => {
       { foo: 'bar' },
       { agent, authorizedDid: 'did:example:123' },
     )
+  })
+
+  it('should be possible to define context type', () => {
+    interface IContext {
+      name: string
+      authorizedDid: string
+    }
+    const agent = createAgent<IResolver, IContext>({
+      context: {
+        name: 'Agent name',
+        authorizedDid: 'did:example:123',
+      },
+    })
+
+    expect(agent.context?.name).toEqual('Agent name')
+    expect(agent.context?.authorizedDid).toEqual('did:example:123')
+  })
+
+  it('context type should be optional', () => {
+    const agent = createAgent<IResolver>({
+      context: {
+        name: 'Agent name',
+        authorizedDid: 'did:example:123',
+      },
+    })
 
+    expect(agent.context?.name).toEqual('Agent name')
     expect(agent.context?.authorizedDid).toEqual('did:example:123')
   })
 

packages/core/src/agent.ts

@@ -309,7 +309,9 @@ export class Agent implements IAgent {
  * @returns configured agent
  * @public
  */
-export function createAgent<T extends IPluginMethodMap>(options: IAgentOptions): TAgent<T> {
+export function createAgent<T extends IPluginMethodMap, C = Record<string, any>>(
+  options: IAgentOptions & { context?: C },
+): TAgent<T> & { context?: C } {
   //@ts-ignore
   return new Agent(options)
 }