chore: handle better build errors

src/build.js

@@ -3,6 +3,7 @@ const os = require('os')
 const path = require('path')
 const CleanCSS = require('clean-css')
 const yaml = require('js-yaml')
+const { log } = require('./message')
 
 const nodePandoc = require('./node-pandoc-promise')
 
@@ -20,6 +21,7 @@ const {
   opfSubstitutions,
   appendExtraMetadata,
 } = require('./edition')
+const { build } = require('joi')
 
 const FORMATS = [
   { name: 'LaTeX', extension: 'tex' },
@@ -87,6 +89,9 @@ module.exports = async (config, options = {}) => {
 
   let args = config.files
 
+  // Suppress warning messages
+  args.push('--quiet')
+
   if (config.format === 'epub' || config.format === 'mobi') {
     // add stylesheet
     let cssContent = ''
@@ -179,7 +184,11 @@ module.exports = async (config, options = {}) => {
   args.push('-o', outputFile)
 
   // compile with pandoc
-  await nodePandoc('', args, { cwd })
+  const buildLogs = await nodePandoc('', args, { cwd }, undefined, { debug: options.debug })
+
+  if (options.debug) {
+    log(buildLogs)
+  }
 
   if (config.format === 'epub' || config.format === 'mobi') {
     // Automatically edit epub: apply substitutions, append extra metadata

src/kindlegen.js

@@ -100,6 +100,9 @@ module.exports.epubToMobi = (input, output, options = {}) => {
       opts.push('-verbose')
     }
     opts.push(input)
+    if (options.debug) {
+      log(`${kindlegenPath} ${opts.join(' ')}`)
+    }
     let kindlegen = spawn(kindlegenPath, opts)
     kindlegen.on('close', async (code) => {
       if (code !== 0 && code !== 1) {

src/node-pandoc-promise.js

@@ -1,57 +1,58 @@
 const stat = require('fs').stat
 const spawn = require('child_process').spawn
+const { log } = require('./message')
+
+module.exports = function (src, args = [], spawnOptions = {}, pandocPath = 'pandoc', options = {}) {
+  if (options.debug) {
+    log(JSON.stringify(spawnOptions, 0, 2))
+    log(`${pandocPath} ${args.join(' ')}`)
+  }
 
-module.exports = function (src, args = [], options = {}, pandocPath = 'pandoc') {
   return new Promise((resolve, reject) => {
-    let pdSpawn
     let result = ''
-    let isURL
+    let error = ''
 
     // Event Handlers
-    let onStdOutData
-    let onStdOutEnd
-    let onStdErrData
-    let onStatCheck
-
-    isURL = function (src) {
-      return /^(https?|ftp):\/\//i.test(src)
-    }
-
-    onStdOutData = function (data) {
+    const onOut = function (data) {
       result += data
     }
 
-    onStdOutEnd = function () {
-      resolve(result)
+    const onErr = function (data) {
+      error += data
     }
 
-    onStdErrData = function (err) {
-      reject(new Error(err))
+    const onEnd = function () {
+      if (error !== '') {
+        reject(new Error(error))
+      } else {
+        resolve(result)
+      }
     }
 
-    onStatCheck = function (err, stats) {
+    // Check if src is URL match.
+    const isURL = /^(https?|ftp):\/\//i.test(src)
+
+    const onStatCheck = function (_err, stats) {
       // If src is a file or valid web URL, push the src back into args array
       if ((stats && stats.isFile()) || isURL) {
         args.unshift(src)
       }
 
       // Create child_process.spawn
-      pdSpawn = spawn(pandocPath, args, options)
+      const pdSpawn = spawn(pandocPath, args, spawnOptions)
 
       // If src is not a file, assume a string input.
       if (typeof stats === 'undefined' && !isURL) {
         pdSpawn.stdin.end(src, 'utf-8')
       }
 
       // Set handlers...
-      pdSpawn.stdout.on('data', onStdOutData)
-      pdSpawn.stdout.on('end', onStdOutEnd)
-      pdSpawn.on('error', onStdErrData)
+      pdSpawn.stdout.on('data', onOut)
+      pdSpawn.stdout.on('end', onEnd)
+      pdSpawn.stderr.on('data', onErr)
+      pdSpawn.stderr.on('end', onEnd)
     }
 
-    // Check if src is URL match.
-    isURL = isURL(src)
-
     // Check file status of src
     stat(src, onStatCheck)
   })