Add "agoric" adapter (#114)

* feat: add Agoric adapter

* fix: use agoric_oracle_query_id

* fix: make more explicit

* test: remove agoric/test

* fix: another attempt to plumb through the 'Task Run Data'

* fix: use the promise-based API

* fix: make request_id numeric

* fix: cast payment from number to string

* fix: properly export the Agoric async adapter and string queryId

* refactor: separate concerns and add tests

* fix: more robust adapter; send errors to the oracleServer

* feat!: surface errors from the oracle backend

* fix: match with actual POST reply from the ag-solo

* fix: use AdapterErrors to surface errors to the node operator

* test: add integration test

* fix: use Requester instead of axios

* chore: rename package to @chainlink/agoric

* ci: add "agoric" to adapters.json

* refactor: clarify implementation according to review comments

* refactor: use the adapter-test-helpers

* ci: fix the Agoric build process

* fix: address review comments

* refactor: standardize code based on example adapter

* fix: import makeConfig

* fix: correct the default agoric adapter parameters

* chore: remove dependency on bn.js

.github/strategy/adapters.json

@@ -7,6 +7,7 @@
     "image_name": "__ADAPTER__-adapter",
     "adapter": [
       "1forge",
+      "agoric",
       "alphachain",
       "alphavantage",
       "amberdata",

CHANGELOG.md

@@ -6,6 +6,11 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased]
 
+### Added
+
+- New adapters:
+  - `agoric` to push results to the Agoric blockchain
+
 ## [0.2.0-rc.1] - 2021-2-4
 
 ### Added

agoric/.eslintrc.js

@@ -0,0 +1,3 @@
+module.exports = {
+  ...require('../.eslintrc.ts.js'),
+}

agoric/README.md

@@ -0,0 +1,39 @@
+# Chainlink External Adapter for Agoric
+
+This adapter posts a result to the [Agoric blockchain](https://agoric.com).  See
+the [Agoric Chainlink Oracle
+integration](https://github.com/Agoric/dapp-oracle/tree/master/chainlink-agoric)
+for details on how to use it with your Chainlink node.
+
+
+| Required? |   Name   |     Description     |           Options            | Defaults to |
+| :-------: | :------: | :-----------------: | :--------------------------: | :---------: |
+|           | endpoint | The endpoint to use | [agoric](#Agoric-endpoint) |   agoric   |
+
+---
+
+## Agoric endpoint
+
+This is the endpoint exposed by your local `ag-solo` after installing the
+[Agoric Chainlink Oracle
+integration](https://github.com/Agoric/dapp-oracle/tree/master/chainlink-agoric).
+
+The default is http://localhost:8000/api/oracle
+
+### Input Params
+
+| Required? |            Name            |               Description                |       Options       | Defaults to |
+| :-------: | :------------------------: | :--------------------------------------: | :-----------------: | :---------: |
+|    ✅     | `request_id`  |   The Agoric oracle queryId    | string | request_id from Agoric External Initiator        |
+|         | `payment` | How much $LINK the Chainlink node would like to collect as a fee | number as a string | the whole fee the user offered |
+|    ✅     | `result` | The result to return to the Agoric oracle contract | string |  |
+
+## Output
+
+```json
+{
+ "jobRunID": "278c97ffadb54a5bbb93cfec5f7b5503",
+ "data": { "result": "..." },
+ "statusCode": 200
+}
+```

agoric/package.json

@@ -0,0 +1,44 @@
+{
+  "name": "@chainlink/agoric-adapter",
+  "version": "0.0.1",
+  "description": "Chainlink adapter to post to the Agoric blockchain",
+  "keywords": [
+    "Chainlink",
+    "LINK",
+    "blockchain",
+    "oracle"
+  ],
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "files": [
+    "dist"
+  ],
+  "repository": {
+    "url": "https://github.com/smartcontractkit/external-adapters-js",
+    "type": "git"
+  },
+  "license": "MIT",
+  "scripts": {
+    "prepublishOnly": "yarn build && yarn test:unit",
+    "setup": "yarn build",
+    "build": "tsc -b",
+    "lint": "eslint --ignore-path ../.eslintignore . --ext .js,.jsx,.ts,.tsx",
+    "lint:fix": "eslint --ignore-path ../.eslintignore . --ext .js,.jsx,.ts,.tsx --fix",
+    "test": "mocha --exit --timeout 3000 -r ts-node/register 'test/**/*.test.ts'",
+    "test:unit": "mocha --exit --grep @integration --invert -r ts-node/register 'test/**/*.test.ts'",
+    "test:integration": "mocha --exit --timeout 3000 --grep @integration -r ts-node/register 'test/**/*.test.ts'",
+    "server": "node -e 'require(\"./index.js\").server()'",
+    "server:dist": "node -e 'require(\"./dist/index.js\").server()'",
+    "start": "yarn server:dist"
+  },
+  "devDependencies": {
+    "@types/chai": "^4.2.11",
+    "@types/express": "^4.17.6",
+    "@types/mocha": "^7.0.2",
+    "@types/node": "^14.0.13",
+    "@typescript-eslint/eslint-plugin": "^3.9.0",
+    "@typescript-eslint/parser": "^3.9.0",
+    "ts-node": "^8.10.2",
+    "typescript": "^3.9.7"
+  }
+}

agoric/src/adapter.ts

@@ -0,0 +1,117 @@
+import { BigNumber } from 'ethers'
+
+import { Config, ExecuteWithConfig, ExecuteFactory } from '@chainlink/types'
+import { Requester, Validator, AdapterError } from '@chainlink/external-adapter'
+
+import { makeConfig } from './config'
+
+// We're on localhost, so retries just confuse the oracle state.
+const NUM_RETRIES = 1
+
+export interface Action {
+  type: string
+  data: unknown
+}
+
+const inputParams = {
+  request_id: ['request_id'],
+  result: ['result'],
+  payment: ['payment'],
+}
+
+// FIXME: Ideally, these would be the same.
+const LINK_UNIT = BigNumber.from(10).pow(BigNumber.from(18))
+const LINK_AGORIC_UNIT = BigNumber.from(10).pow(BigNumber.from(6))
+
+// Convert the payment in $LINK into Agoric's pegged $LINK token.
+export const getRequiredFee = (value: string | number): number => {
+  const paymentCL = BigNumber.from(value)
+  const paymentAgoricLink = paymentCL.mul(LINK_AGORIC_UNIT).div(LINK_UNIT)
+  return paymentAgoricLink.toNumber()
+}
+
+export interface PostReply {
+  ok: boolean
+  res?: unknown
+  rej?: unknown
+}
+
+const executeImpl: ExecuteWithConfig<Config> = async (request, config) => {
+  const validator = new Validator(request, inputParams)
+  if (validator.error) {
+    throw validator.error
+  }
+
+  Requester.logConfig(config)
+
+  const jobRunID = validator.validated.id
+  const { request_id: queryId, result, payment } = validator.validated.data
+  const requiredFee = getRequiredFee(payment)
+
+  const obj = {
+    type: 'oracleServer/reply',
+    data: { queryId, reply: result, requiredFee },
+  }
+
+  const response = await Requester.request(
+    {
+      ...config.api,
+      method: 'POST',
+      data: obj,
+    },
+    undefined,
+    NUM_RETRIES,
+  )
+
+  const pr = response.data as PostReply
+  if (!pr.ok) {
+    throw Error(`${obj.type} response failed: ${pr.rej}`)
+  }
+
+  return Requester.success(jobRunID, {
+    data: { result },
+    result,
+    status: 200,
+  })
+}
+
+const tryExecuteLogError = (
+  execute: ExecuteWithConfig<Config>,
+): ExecuteWithConfig<Config> => async (request, config) => {
+  try {
+    return await execute(request, config)
+  } catch (e) {
+    const queryId = request.data?.request_id
+    const rest = { queryId }
+
+    await Requester.request(
+      {
+        ...config.api,
+        method: 'POST',
+        data: {
+          type: 'oracleServer/error',
+          data: { error: `${(e && e.message) || e}`, ...(queryId && rest) },
+        },
+      },
+      undefined,
+      NUM_RETRIES,
+    ).catch((e2: Error) => console.error(`Cannot reflect error to caller:`, e2))
+
+    // See https://github.com/smartcontractkit/external-adapters-js/issues/204
+    // for discussion of why this code is necessary.
+    if (e instanceof AdapterError) {
+      throw e
+    }
+    throw new AdapterError({
+      jobRunID: request.id,
+      statusCode: 500,
+      message: `${(e && e.message) || e}`,
+      cause: e,
+    })
+  }
+}
+
+export const execute = tryExecuteLogError(executeImpl)
+export const makeExecute: ExecuteFactory<Config> = (config) => {
+  return async (request) => execute(request, config || makeConfig())
+}

agoric/src/config.ts

@@ -0,0 +1,17 @@
+import { Requester } from '@chainlink/external-adapter'
+import { Config } from '@chainlink/types'
+import { util } from '@chainlink/ea-bootstrap'
+
+export const DEFAULT_API_ENDPOINT = 'http://localhost:8000/api/oracle'
+
+// This environment variable is needed for the Hack the Orb oracle
+// instructions to remain correct.
+const LEGACY_API_ENDPOINT_ENV = 'AG_SOLO_ORACLE_URL'
+
+export const makeConfig = (prefix?: string): Config => {
+  const config = Requester.getDefaultConfig(prefix)
+  config.api.baseURL =
+    config.api.baseURL || util.getEnv(LEGACY_API_ENDPOINT_ENV) || DEFAULT_API_ENDPOINT
+  config.apiKey = config.apiKey || 'not required'
+  return config
+}

agoric/src/index.ts

@@ -0,0 +1,7 @@
+import { expose } from '@chainlink/ea-bootstrap'
+import { makeExecute } from './adapter'
+import { makeConfig } from './config'
+
+const NAME = 'Agoric'
+
+export = { NAME, makeExecute, makeConfig, ...expose(makeExecute()) }