fix(reporter): Handle incorrect being piped to the cli

lib/reporter.js

@@ -1,7 +1,9 @@
+const terminalLink = require('terminal-link')
 const Handlebars = require('handlebars')
 const moment = require('moment')
 const marked = require('marked')
 const fse = require('fs-extra')
+const chalk = require('chalk')
 const fs = require('fs')
 const { promisify } = require('util')
 
@@ -54,6 +56,30 @@ const modifyData = async data => {
 
 module.exports = async (data, templateFile, outputFile) => {
   try {
+    if (!data.metadata) {
+      if (data.updated) {
+        console.log(
+          chalk.red(
+            `Sorry! You can't use ${chalk.underline(
+              'npm audit fix'
+            )} with npm-audit-html.\n\nSee ${terminalLink(
+              'issue #3',
+              'https://github.com/Filiosoft/npm-audit-html/issues/3'
+            )}`
+          )
+        )
+      } else {
+        console.log(
+          chalk.red(
+            `The provided data doesn't seem to be correct. Did you run with ${chalk.underline(
+              'npm audit --json'
+            )}?`
+          )
+        )
+      }
+      process.exit(1)
+    }
+
     const modifiedData = await modifyData(data)
     const report = await generateTemplate(modifiedData, templateFile)
     await writeReport(report, outputFile)

package.json

@@ -38,11 +38,13 @@
     "travis-deploy-once": "^5.0.0"
   },
   "dependencies": {
+    "chalk": "^2.4.1",
     "commander": "^2.15.1",
     "fs-extra": "^7.0.1",
     "handlebars": "^4.0.11",
     "marked": "^0.4.0",
-    "moment": "^2.22.2"
+    "moment": "^2.22.2",
+    "terminal-link": "^1.1.0"
   },
   "config": {
     "commitizen": {