feat: add internal polling inbound transporter (#323)

Author: TimoGlastra

docs/getting-started/1-transports.md

@@ -27,65 +27,22 @@ agent.setOutboundTransporter(wsOutboundTransporter)
 
 ## Inbound Transport
 
-Inbound transports allow you to receive messages from other agents. No inbound transports are exported from the framework at the moment. See the example transports below to get started.
+Inbound transports allow you to receive messages from other agents. Only `PollingInboundTransporter` is exported from the framework at the moment. Make sure you provide a `mediatorUrl` if using the polling inbound transporters. See the example transports below for other inbound transports.
 
 ```ts
+import { Agent, PollingInboundTransporter } from 'aries-framework'
+
 const agentConfig = {
   // ... agent config ... //
+  mediatorUrl: 'https://your-afj-mediator-url.com',
 }
 
-const someInboundTransport = new SomeInboundTransport()
-
 const agent = new Agent(agentConfig)
-agent.setInboundTransporter(someInboundTransport)
-```
-
-### Example `PollingInboundTransporter`
-
-This is an example of a polling inbound transport. This is mostly useful for edge agents, that use a mediator to receive inbound messages. Make sure to provide a `mediatorUrl` in the agent config when using this transport. See [3. Routing](./3-routing.md) for more information.
 
-```ts
-import { Agent, InboundTransporter } from 'aries-framework'
-
-// In React Native you don't have to import node-fetch
-// Fetch is globally available in React Native
-import fetch from 'node-fetch'
-
-class PollingInboundTransporter implements InboundTransporter {
-  public stop: boolean
+// Construct polling inbound transporter with optional polling interval in ms
+const pollingInboundTransporter = new PollingInboundTransporter(5000)
 
-  public constructor() {
-    this.stop = false
-  }
-  public async start(agent: Agent) {
-    await this.registerMediator(agent)
-  }
-
-  public async registerMediator(agent: Agent) {
-    const mediatorUrl = agent.getMediatorUrl()
-
-    if (!mediatorUrl) {
-      throw new AriesFrameworkError(
-        'Agent has no mediator URL. Make sure to provide the `mediatorUrl` in the agent config.'
-      )
-    }
-
-    const mediatorInvitationUrl = await get(`${mediatorUrl}/invitation`)
-    const { verkey: mediatorVerkey } = JSON.parse(await get(`${mediatorUrl}/`))
-    await agent.routing.provision({
-      verkey: mediatorVerkey,
-      invitationUrl: mediatorInvitationUrl,
-    })
-    this.pollDownloadMessages(agent)
-  }
-
-  private async pollDownloadMessages(agent: Agent) {
-    while (!this.stop) {
-      await agent.routing.downloadMessages()
-      await sleep(5000)
-    }
-  }
-}
+agent.setInboundTransporter(pollingInboundTransporter)
 ```
 
 ### Example `HttpInboundTransporter`

src/__tests__/helpers.ts

@@ -33,8 +33,6 @@ export const genesisPath = process.env.GENESIS_TXN_PATH
 
 export const publicDidSeed = process.env.TEST_AGENT_PUBLIC_DID_SEED ?? '000000000000000000000000Trustee9'
 
-export const sleep = (ms: number) => new Promise((res) => setTimeout(res, ms))
-
 export function getBaseConfig(name: string, extraConfig: Partial<InitConfig> = {}) {
   const config: InitConfig = {
     label: `Agent: ${name}`,

src/__tests__/ledger.test.ts

@@ -5,8 +5,9 @@ import indy from 'indy-sdk'
 
 import { Agent } from '../agent/Agent'
 import { DID_IDENTIFIER_REGEX, VERKEY_REGEX, isFullVerkey, isAbbreviatedVerkey } from '../utils/did'
+import { sleep } from '../utils/sleep'
 
-import { genesisPath, getBaseConfig, sleep } from './helpers'
+import { genesisPath, getBaseConfig } from './helpers'
 import testLogger from './logger'
 
 const faberConfig = getBaseConfig('Faber Ledger', { genesisPath })

src/transport/PollingInboundTransporter.ts

@@ -0,0 +1,49 @@
+import type { Agent } from '../agent/Agent'
+import type { InboundTransporter } from './InboundTransporter'
+
+import { AriesFrameworkError } from '../error/AriesFrameworkError'
+import { fetch } from '../utils/fetch'
+import { sleep } from '../utils/sleep'
+
+export class PollingInboundTransporter implements InboundTransporter {
+  public stop: boolean
+  private pollingInterval: number
+
+  public constructor(pollingInterval = 5000) {
+    this.stop = false
+    this.pollingInterval = pollingInterval
+  }
+
+  public async start(agent: Agent) {
+    await this.registerMediator(agent)
+  }
+
+  public async registerMediator(agent: Agent) {
+    const mediatorUrl = agent.getMediatorUrl()
+
+    if (!mediatorUrl) {
+      throw new AriesFrameworkError(
+        'Agent has no mediator URL. Make sure to provide the `mediatorUrl` in the agent config.'
+      )
+    }
+
+    const invitationResponse = await fetch(`${mediatorUrl}/invitation`)
+    const invitationUrl = await invitationResponse.text()
+
+    const mediatorDidResponse = await fetch(`${mediatorUrl}`)
+    const { verkey } = await mediatorDidResponse.json()
+
+    await agent.routing.provision({
+      verkey,
+      invitationUrl,
+    })
+    this.pollDownloadMessages(agent)
+  }
+
+  private async pollDownloadMessages(agent: Agent) {
+    while (!this.stop) {
+      await agent.routing.downloadMessages()
+      await sleep(this.pollingInterval)
+    }
+  }
+}

src/transport/index.ts

@@ -2,3 +2,4 @@ export * from './InboundTransporter'
 export * from './OutboundTransporter'
 export * from './HttpOutboundTransporter'
 export * from './WsOutboundTransporter'
+export * from './PollingInboundTransporter'

src/utils/sleep.ts

@@ -0,0 +1,3 @@
+export function sleep(ms: number) {
+  return new Promise((res) => setTimeout(res, ms))
+}

tests/__tests__/e2e.test.ts

@@ -1,7 +1,5 @@
-import type { InboundTransporter } from '../../src'
-
-import { Agent, AriesFrameworkError, HttpOutboundTransporter } from '../../src'
-import { getBaseConfig, sleep, waitForBasicMessage } from '../../src/__tests__/helpers'
+import { Agent, HttpOutboundTransporter, PollingInboundTransporter } from '../../src'
+import { getBaseConfig, waitForBasicMessage } from '../../src/__tests__/helpers'
 import logger from '../../src/__tests__/logger'
 import { get } from '../http'
 
@@ -93,39 +91,3 @@ describe('with mediator', () => {
     expect(basicMessage.content).toBe(message)
   })
 })
-
-class PollingInboundTransporter implements InboundTransporter {
-  public stop: boolean
-
-  public constructor() {
-    this.stop = false
-  }
-  public async start(agent: Agent) {
-    await this.registerMediator(agent)
-  }
-
-  public async registerMediator(agent: Agent) {
-    const mediatorUrl = agent.getMediatorUrl()
-
-    if (!mediatorUrl) {
-      throw new AriesFrameworkError(
-        'Agent has no mediator URL. Make sure to provide the `mediatorUrl` in the agent config.'
-      )
-    }
-
-    const mediatorInvitationUrl = await get(`${mediatorUrl}/invitation`)
-    const { verkey: mediatorVerkey } = JSON.parse(await get(`${mediatorUrl}/`))
-    await agent.routing.provision({
-      verkey: mediatorVerkey,
-      invitationUrl: mediatorInvitationUrl,
-    })
-    this.pollDownloadMessages(agent)
-  }
-
-  private async pollDownloadMessages(agent: Agent) {
-    while (!this.stop) {
-      await agent.routing.downloadMessages()
-      await sleep(5000)
-    }
-  }
-}