Improve cli interface (#95)

* improve cli interface and add examples to readme
* fix first example to use json string rather than number
* organize code, better error output, add string input validation
* re-add buffer hex encoding
Co-authored-by: acolytec3 <17355484+acolytec3@users.noreply.github.com>

README.md

@@ -33,8 +33,15 @@ assert.deepEqual(nestedList, decoded)
 
 ## CLI
 
-`rlp decode <hex string>`  
-`rlp encode <json String>`
+`rlp encode <JSON string>`
+`rlp decode <0x-prefixed hex string>`
+
+### Examples
+
+- `rlp encode '5'` => `0x05`
+- `rlp encode '[5]'` => `0xc105`
+- `rlp encode '["cat", "dog"]'` => `0xc88363617483646f67`
+- `rlp decode 0xc88363617483646f67` => `["cat","dog"]`
 
 ## TESTS
 

bin/rlp

@@ -1,35 +1,53 @@
 #!/usr/bin/env node
 
 const rlp = require('../dist/index.js')
-const command = process.argv[2]
-var raw = process.argv[3]
+const method = process.argv[2]
+const strInput = process.argv[3]
 
-if (command === 'encode') {
+if (typeof strInput !== 'string') {
+  return console.error(`Expected JSON string input, received type: ${typeof strInput}`)
+}
+
+if (method === 'encode') {
+  // Parse JSON
+  let json
   try {
-    const json = JSON.parse(raw)
-    console.log(rlp.encode(json).toString('hex'))
-  } catch (e) {
-    console.log('invalid json')
-  }
-} else {
-  if (!raw) {
-    raw = command
+    json = JSON.parse(strInput)
+  } catch (error) {
+    return console.error(`Error could not parse JSON: ${JSON.stringify(error)}`)
   }
+
+  // Encode RLP
   try {
-    console.log(baToJSON(rlp.decode(raw)))
+    const encoded = rlp.encode(json)
+    console.log('0x' + encoded.toString('hex'))
   } catch (e) {
-    console.log('invalid RLP' + e)
+    console.error(`Error encoding RLP: ${JSON.stringify(error)}`)
+  }
+} else if (method === 'decode') {
+  // Decode
+  try {
+    const decoded = rlp.decode(strInput)
+    const json = JSON.stringify(baToJSON(decoded))
+    console.log(json)
+  } catch (error) {
+    console.error(`Error decoding RLP: ${JSON.stringify(error)}`)
   }
+} else {
+  console.error('Unsupported method')
 }
 
-function baToJSON (ba) {
+/**
+ * Buffer or Buffer Array to JSON
+ */
+function baToJSON(ba) {
   if (Buffer.isBuffer(ba)) {
     return ba.toString('hex')
   } else if (ba instanceof Array) {
-    var array = []
-    for (var i = 0; i < ba.length; i++) {
-      array.push(baToJSON(ba[i]))
+    const arr = []
+    for (let i = 0; i < ba.length; i++) {
+      arr.push(baToJSON(ba[i]))
     }
-    return array
+    return arr
   }
 }

test/integration.spec.ts

@@ -1,5 +1,6 @@
 import * as assert from 'assert'
 import { exec } from 'child_process'
+import { promisify } from 'util'
 import * as RLP from '../dist'
 import * as vm from 'vm'
 
@@ -11,11 +12,34 @@ describe('Distribution:', function () {
   })
 })
 
+const execAsync = promisify(exec)
+
 describe('CLI command:', function () {
-  it('should be able to run CLI command', function () {
-    exec('./bin/rlp encode "[ 5 ]"', (_error, stdout) => {
-      assert.strictEqual(stdout.trim(), 'c105')
-    })
+  it('should be able to run CLI command', async function () {
+    const result = await execAsync('./bin/rlp encode "[ 5 ]"')
+    const resultFormatted = result.stdout.trim()
+    assert.strictEqual(resultFormatted, '0xc105')
+  })
+
+  const officalTests = require('./fixture/rlptest.json').tests
+  it('should return valid values for official tests', async function () {
+    // eslint-disable-next-line no-invalid-this
+    this.timeout(10000)
+
+    // eslint-disable-next-line no-restricted-syntax
+    for (const testName in officalTests) {
+      const { in: incoming, out } = officalTests[testName]
+
+      // skip if testing a big number
+      if (incoming[0] === '#') {
+        continue
+      }
+
+      const json = JSON.stringify(incoming)
+      const encodeResult = await execAsync(`./bin/rlp encode '${json}'`)
+      const encodeResultTrimmed = encodeResult.stdout.trim()
+      assert.strictEqual(encodeResultTrimmed, out.toLowerCase(), `should pass encoding ${testName}`)
+    }
   })
 })