adds configurationFor utility to auth

auth.js

@@ -2,6 +2,16 @@
 
 const crypto = require('crypto')
 
+exports.configurationFor = ({ sandbox, hostname, key, passphrase, secret } = Object.prototype) => {
+  return {
+    npm_config_coinbase_pro_api_sandbox: String(sandbox),
+    npm_config_coinbase_pro_api_hostname: hostname,
+    npm_config_coinbase_pro_api_key: key,
+    npm_config_coinbase_pro_api_passphrase: passphrase,
+    npm_config_coinbase_pro_api_secret: secret
+  }
+}
+
 exports.signatureFor = ({ timestamp, method, path = String.prototype, body = String.prototype }, { npm_config_coinbase_pro_api_secret = String.prototype } = process.env, { createHmac } = crypto) => {
   const buffer = Buffer.from(npm_config_coinbase_pro_api_secret, 'base64')
   return createHmac('sha256', buffer)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "coinbase-pro-api",
-  "version": "0.0.6",
+  "version": "0.1.0",
   "description": "lightweight coinbase pro api implementation",
   "main": "index.js",
   "config": {

test/auth.js

@@ -1,5 +1,40 @@
 test('coinbase-pro-api/auth', () => {
-  const { deepStrictEqual } = require('assert')
+  const { ok, strictEqual, deepStrictEqual } = require('assert')
+
+  test('.configurationFor', () => {
+    const { configurationFor } = require('../auth')
+
+    test('is callable', () => {
+      deepStrictEqual(typeof configurationFor, 'function')
+    })
+
+    test('returns empty configuration object by default', () => {
+      const configuration = configurationFor(undefined)
+      ok(configuration.hasOwnProperty('npm_config_coinbase_pro_api_sandbox'))
+      ok(configuration.hasOwnProperty('npm_config_coinbase_pro_api_hostname'))
+      ok(configuration.hasOwnProperty('npm_config_coinbase_pro_api_key'))
+      ok(configuration.hasOwnProperty('npm_config_coinbase_pro_api_passphrase'))
+      ok(configuration.hasOwnProperty('npm_config_coinbase_pro_api_secret'))
+    })
+
+    test('returns object env compatible object', () => {
+      const configuration = configurationFor({
+        sandbox: false,
+        hostname: 'hostname',
+        key: 'key',
+        passphrase: 'passphrase',
+        secret: 'secret'
+      })
+
+      deepStrictEqual(configuration, {
+        npm_config_coinbase_pro_api_sandbox: 'false',
+        npm_config_coinbase_pro_api_hostname: 'hostname',
+        npm_config_coinbase_pro_api_key: 'key',
+        npm_config_coinbase_pro_api_passphrase: 'passphrase',
+        npm_config_coinbase_pro_api_secret: 'secret'
+      })
+    })
+  })
 
   test('.signatureFor', () => {
     const { signatureFor } = require('../auth')
@@ -8,7 +43,7 @@ test('coinbase-pro-api/auth', () => {
       deepStrictEqual(typeof signatureFor, 'function')
     })
 
-    test('creates base64 encoded sha256 hmac signature using crypto', (done) => {
+    test('creates base64 encoded sha256 hmac signature', (done) => {
       signatureFor({ timestamp: 1, method: 'get' }, undefined, {
         createHmac (algorithm) {
           deepStrictEqual(algorithm, 'sha256')
@@ -27,6 +62,11 @@ test('coinbase-pro-api/auth', () => {
       })
     })
 
+    test('defaults to crypto library', () => {
+      const signature = signatureFor({ timestamp: 1, method: 'get' })
+      strictEqual(Buffer.from(signature, 'base64').toString('base64'), signature)
+    })
+
     test('takes an optional secret argument', (done) => {
       const secret = Buffer.from('secret').toString('base64')
       signatureFor({ timestamp: 1, method: 'get' }, { npm_config_coinbase_pro_api_secret: secret }, {