Fix a bug in db test, finished application update. Fixed a few bugs and did some refactoring. Started on application.run() functionality

core/application.mjs

@@ -1,5 +1,6 @@
 import { EventEmitter } from 'events'
 import fs from 'fs/promises'
+import HttpServer from './http.mjs'
 
 export default class Application extends EventEmitter {
   constructor(util, db, provider, name, opts = {}) {
@@ -10,6 +11,22 @@ export default class Application extends EventEmitter {
     this.provider = provider
     this.name = name
     this.updating = false
+    this.http = new HttpServer(this.config)
+    this.module = null
+    this.running = false
+
+    // Fresh is used to indicate that when we run the application and it fails,
+    // whether the environment we are in was fresh or not. An example would be
+    // if we had previously run an older version. In that case, that older version
+    // might have dirtied the runtime or left a port open or other stuff.
+    // In which case, running the new version might fail even though it should
+    // normally be fine. As such we have this flag here. to indicate we might
+    // need a full restart before making another attempt.
+    this.fresh = true
+
+    // Apply defaults to config
+    this.config.updateEvery = this.config.updateEvery || 180
+    this.config.waitUntilFail = this.config.waitUntilFail || (60 * 1000)
 
     Object.assign(this, {
       setInterval: opts.setInterval || setInterval,
@@ -31,7 +48,7 @@ export default class Application extends EventEmitter {
           this.db.data.core[this.name].updater += 'Error while running automatic update: ' + err.message + '. '
         }
       )
-    }, (this.config.updateEvery || 180) * 60 * 1000)
+    }, this.config.updateEvery * 60 * 1000)
     timer.unref()
   }
 
@@ -41,15 +58,44 @@ export default class Application extends EventEmitter {
     return message
   }
 
-  async update() {
-    if (this.updating) return
+  msgStatic = 'Provider in question is static and so no update required, nothing to do.'
 
+  update() {
     if (this.provider.static) {
-      this.updateLog('Provider in question is static and so no update required, nothing to do.')
-      return
+      if (this.db.data.core[this.name].updater !== this.msgStatic) {
+        this.db.data.core[this.name].updater = ''
+        this.updateLog(this.msgStatic)
+        return this.db.write()
+      }
+      return Promise.resolve()
     }
 
+    if (this.updating) return
     this.updating = true
+
+    return this._update()
+      .then(() => {
+        this.updating = false
+        return this.db.write()
+      })
+      .catch((err) => {
+        this.updating = false
+        return this.db.write()
+          .then(function() { return Promise.reject(err) })
+      })
+  }
+
+  logAddSeperator(log) {
+    if (!log.endsWith('\n')) {
+      log += '\n'
+    }
+    if (!log.endsWith('\n\n')) {
+      log += '\n'
+    }
+    return log
+  }
+
+  async _update() {
     this.db.data.core[this.name].updater = ''
     let cleanup = true
     let folder = ''
@@ -59,45 +105,70 @@ export default class Application extends EventEmitter {
     try {
       log += this.updateLog(`Checking for latest version at ${new Date().toISOString().replace('T', ' ').split('.')[0]}. `) + '\n'
 
+      // Get the latest version from our provider
       latest = await this.provider.getLatestVersion()
 
       log += this.updateLog(`Found ${latest.version}. `) + '\n'
 
+      // If the versino matches the latest installed, then there's nothing to do
       if (this.db.data.core[this.name].latestInstalled === latest.version) {
         this.updateLog('Already up to date, nothing to do. ')
-        this.updating = false
         return
       }
       
+      // Make the id for the vesion the version number. Allows for easy lookup
+      // among other nice and simple structure.
       latest.id = latest.version
+
+      // check to see if we already have this version in our database.
       var found = this.db.get(this.db.data.core[this.name].versions, latest.id)
       if (found) {
+        // Check if the existing version found was already installed.
+        if (found.installed) {
+          this.updateLog('Version was already installed, nothing to do. ')
+          return
+        }
+
+        // We found existing on, update the keys of the one in the databse with
+        // the latest data we got from getLatestVersion(). This ensures that info
+        // like link, filename and such get updated if these have changed since.
         Object.keys(latest).forEach(function(key) {
           found[key] = latest[key]
         })
         latest = found
+        
+        // Check to see if the existing one has failed too many times and
+        // if so, we should skip them and consider those versions as black
+        // listed and avoid at all cost.
+        if (latest.failtodownload && latest.failtodownload > 3) {
+          this.updateLog('Version failed to download too many times, skipping this version. ')
+          return
+        }
+
+        if (latest.failtoinstall && latest.failtoinstall > 3) {
+          this.updateLog('Version failed to install too many times, skipping this version. ')
+          return
+        }
+
+        // Combine the logs
         log = latest.log + log
       } else {
-        this.db.upsert(this.db.data.core[this.name].versions, latest)
-      }
-
-      if (latest.failtodownload && latest.failtodownload > 3) {
-        this.updateLog('Version failed to download too many times, skipping this version. ')
-        this.updating = false
-        return
-      }
-      if (latest.failtoinstall && latest.failtoinstall > 3) {
-        this.updateLog('Version failed to install too many times, skipping this version. ')
-        this.updating = false
-        return
+        // This is a new version, mark it with stable tag of zero.
+        latest.stable = 0
+        this.db.upsertFirst(this.db.data.core[this.name].versions, latest)
       }
 
+      // The target file for the archive and the target folder for new our version
       let target = this.util.getPathFromRoot(`./${this.name}/${latest.version}/file${this.util.getExtension(latest.filename)}`)
       folder = this.util.getPathFromRoot(`./${this.name}/${latest.version}`)
 
+      // Create it in case it does not exist.
       await this.fs.mkdir(folder, { recursive: true })
 
       log += this.updateLog(`Downloading ${latest.link} to ${target}. `) + '\n'
+      await this.db.write()
+
+      // Download the latest version using the provider in question.
       await this.provider.downloadVersion(latest, target)
         .catch(function(err) {
           latest.failtodownload = (latest.failtodownload || 0) + 1
@@ -105,6 +176,9 @@ export default class Application extends EventEmitter {
         })
 
       log += '\n' + this.updateLog(`Extracting ${target}. `) + '\n'
+      await this.db.write()
+
+      // Download was successful, extract the archived file that we downloaded
       await this.util.extractFile(target, function(msg) {
         log += msg
       }).catch(function(err) {
@@ -112,15 +186,16 @@ export default class Application extends EventEmitter {
         return Promise.reject(err)
       })
 
+      // Remove the archived file since we're done using it.
       await this.fs.rm(target, { force: true }).catch(function() {})
 
-      if (!log.endsWith('\n')) {
-        log += '\n'
-      }
-      if (!log.endsWith('\n\n')) {
-        log += '\n'
-      }
+      // The extracting process might not leave enough newlines for our
+      // desired clean output for our logs so add them.
+      log = this.logAddSeperator(log)
 
+      // check if the version we downloaded had index.mjs. If this is
+      // missing then either the extracting or download failed without erroring
+      // or the archived is borked.
       await this.fs.stat(this.util.getPathFromRoot(`./${this.name}/${latest.version}/index.mjs`))
         .catch((err) => {
           latest.failtodownload = (latest.failtodownload || 0) + 1
@@ -128,38 +203,44 @@ export default class Application extends EventEmitter {
           return Promise.reject(err)
         })
 
+      // If we reach here, then we don't wanna cleanup or remove existing files
+      // in case more errors occured. The download was success and preliminary
+      // checks indicate the version is valid. As such, we are gonna skip
+      // clearing the folder even if something occurs later on.
       cleanup = false
 
+      // Check if we have a package.json file. If we do, we need to run
+      // npm install. If we don't then this application either has all the
+      // required packages or it doesn't need them to run
       let packageStat = await this.fs.stat(this.util.getPathFromRoot(`./${this.name}/${latest.version}/package.json`))
         .catch(function() { return null })
 
       if (packageStat) {
         log += this.updateLog(`running npm install --production. `) + '\n'
+        await this.db.write()
+
+        // For some weird reason, --loglevel=notice is required otherwise
+        // we get practically zero log output.
         await this.util.runCommand(
           'npm.cmd',
           ['install', '--production', '--no-optional', '--no-package-lock', '--no-audit', '--loglevel=notice'],
           folder,
-          function(msg) {
-            log += msg
-          }
+          function(msg) { log += msg }
         ).catch(function(err) {
           latest.failtoinstall = (latest.failtoinstall || 0) + 1
           return Promise.reject(err)
         })
     
-        if (!log.endsWith('\n')) {
-          log += '\n'
-        }
-        if (!log.endsWith('\n\n')) {
-          log += '\n'
-        }
-
+        log = this.logAddSeperator(log)
       } else {
         log += this.updateLog('Release did not contain package.json, skipping npm install. ') + '\n'
       }
     } catch (err) {
-      this.updating = false
       log += this.updateLog(`Error: ${err.message}. `) + '\n'
+
+      // Check if we have a folder and we need to do some cleanups. We do
+      // this if the download process failed so we can have a fresh clean
+      // tree for the next time update is run
       if (folder && cleanup) {
         await this.fs.rm(folder, { force: true, recursive: true }).catch((err) => {
           this.updateLog(`Error while cleaning up: ${err.message}. `)
@@ -171,9 +252,44 @@ export default class Application extends EventEmitter {
       return Promise.reject(err)
     }
 
+    // If we reached here then everything went swimmingly. Mark the version
+    // as being installed and attach the install log to it.
     log += this.updateLog(`Finished updating ${this.name} to version ${latest.version}.`) + '\n'
     this.db.data.core[this.name].latestInstalled = latest.version
+    latest.installed = true
     latest.log = log
-    this.updating = false
+  }
+
+  registerModule(module) {
+    if (module && typeof(module) === 'function') {
+      return this.registerModule({ start: module })
+    }
+    if (!module || typeof(module) !== 'object' || typeof(module.start) !== 'function') {
+      throw new Error(`Application ${this.name} registerModule was called with a non module missing start function`)
+    }
+
+    this.module = module
+  }
+
+  async runVersion(version) {
+    let module = this.module
+
+    let errTimeout = new Error(`Application ${this.name} version ${version} timed out (took over ${this.config.waitUntilFail}ms) while running start()`)
+
+    await new Promise((res, rej) => {
+      setTimeout(() => {
+        rej(errTimeout)
+      }, this.config.waitUntilFail)
+
+      let startRes = module.start(this.db, this.db.log, this.http, this.config.port)
+      if (startRes && startRes.then) {
+        return startRes.then(res, rej)
+      }
+      res()
+    })
+
+    if (!this.http.active) {
+      return Promise.reject(new Error(`Application ${this.name} version ${version} did not call http.createServer()`))
+    }
   }
 }

core/db.mjs

@@ -55,6 +55,20 @@ export default function GetDB(config, log, orgFilename = 'db.json') {
     col.push(item)
   }
 
+  db.upsertFirst = function(collection, item) {
+    let col = db.getCollection(collection)
+    if (item[db.id]) {
+      let i = db.get(col, item[db.id], true)
+      if (i !== null) {
+        col[i] = item
+        return
+      }
+    } else {
+      item[db.id] = db.createId(col)
+    }
+    col.splice(0, 0, item)
+  }
+
   db.remove = function(collection, itemOrId) {
     let col = db.getCollection(collection)
     let id = itemOrId

core/util.mjs

@@ -32,6 +32,9 @@ export default class Util {
       if (typeof(config[key]) !== 'object' || config[key] == null) continue
       if (typeof(config[key].port) !== 'number' || !config[key].port) continue
       if (typeof(config[key].provider) !== 'string' || !config[key].provider) continue
+      if (config[key].https != null && typeof(config[key].https) !== 'boolean') continue
+      if (config[key].updateEvery != null && (typeof(config[key].updateEvery) !== 'number' || config[key].updateEvery < 1)) continue
+      if (config[key].waitUntilFail != null && (typeof(config[key].waitUntilFail) !== 'number' || config[key].waitUntilFail < 10)) continue
 
       out.push(key)
     }

test/application.run.test.mjs

@@ -0,0 +1,92 @@
+import { Eltro as t, assert, stub } from 'eltro'
+import fs from 'fs/promises'
+import lowdb from '../core/db.mjs'
+import Application from '../core/application.mjs'
+import Util from '../core/util.mjs'
+import StaticProvider from '../core/providers/static.mjs'
+
+const util = new Util(import.meta.url)
+
+const logger = {
+  info: stub(),
+  warn: stub(),
+  error: stub(),
+}
+function createProvider() {
+  return {
+    getLatestVersion: stub(),
+    downloadVersion: stub(),
+  }
+}
+
+t.timeout(250).describe('#runVersion()', function() {
+  const assertPort = 22345
+  let db
+  let app
+
+  const defaultHandler = function(db, log, http, port) {
+    const server = http.createServer(function (req, res) {
+      res.writeHead(204); res.end(JSON.stringify({ a: 1 }))
+    })
+
+    return new Promise(function(res, rej) {
+      server.listen(port, '0.0.0.0', function(err) {
+        if (err) return rej(err)
+        res()
+      })
+    })
+  }
+  
+  t.beforeEach(function() {
+    return lowdb({ test: { } }, logger, null).then(function(res) {
+      db = res
+      let provider = new StaticProvider()
+      app = new Application(util, db, provider, 'testapp')
+      app.config.port = assertPort
+      app.registerModule(defaultHandler)
+    })
+  })
+
+  t.test('should throw if http is not called', async function() {
+    app.registerModule(function(checkDb, checkLog, checkHttp, checkPort) {
+      assert.strictEqual(checkDb, db)
+      assert.strictEqual(checkLog, db.log)
+      assert.strictEqual(checkHttp, app.http)
+      assert.strictEqual(checkPort, assertPort)
+    })
+
+    let err = await assert.isRejected(app.runVersion('static'))
+
+    assert.match(err.message, /http/i)
+    assert.match(err.message, /createServer/i)
+    assert.match(err.message, /static/)
+    assert.match(err.message, new RegExp(app.name))
+    assert.match(err.message, /call/i)
+  })
+
+  t.test('should throw if it timeouts waiting for promise to succeed', async function() {
+    app.config.waitUntilFail = 50
+    app.registerModule(function() { return new Promise(function() {}) })
+    
+    let err = await assert.isRejected(app.runVersion('static'))
+
+    assert.match(err.message, /time/i)
+    assert.match(err.message, /out/i)
+    assert.match(err.message, /static/)
+    assert.match(err.message, /50ms/)
+    assert.match(err.message, new RegExp(app.name))
+  })
+
+  t.test('should otherwise succeed if it finished within the time limit', async function() {
+    app.config.waitUntilFail = 250
+    app.registerModule(function(db, log, http, port) {
+      return new Promise(function(res) {
+        setTimeout(res, 25)
+      }).then(function() {
+        return defaultHandler(db, log, http, port)
+      })
+    })
+    
+    await app.runVersion('static')
+  })
+})

test/application.test.mjs

@@ -52,9 +52,29 @@ t.describe('constructor()', function() {
 
     let app = new Application(util, db, {}, assertName)
     assert.strictEqual(app.config, assertTest)
+    assert.strictEqual(app.config.updateEvery, 180)
+    assert.strictEqual(app.config.waitUntilFail, 60 * 1000)
     assert.strictEqual(app.db, db)
     assert.strictEqual(app.util, util)
     assert.strictEqual(app.name, assertName)
+    assert.strictEqual(app.fresh, true)
+    assert.strictEqual(app.running, false)
+    assert.ok(app.http)
+    assert.ok(app.http.sockets)
+    assert.strictEqual(typeof(app.http.createServer), 'function')
+    assert.strictEqual(typeof(app.http.closeServer), 'function')
+  })
+
+  t.test('should create http instance correctly', function() {
+    db.config = {
+      testapp: { a: 1, https: true },
+      app: { b: 2},
+      manage: { c: 3 },
+    }
+
+    let app = new Application(util, db, {}, 'testapp')
+    assert.ok(app.http)
+    assert.ok(app.http.ishttps)
   })
 
   t.test('should keep provider', function() {
@@ -190,6 +210,7 @@ t.timeout(250).describe('#update()', function() {
     return lowdb({ test: { } }, logger, null).then(function(res) {
       db = res
       db.write = stubWrite = stub()
+      stubWrite.resolves()
       provider = createProvider()
       app = new Application(util, db, provider, 'testapp', {
         fs: {
@@ -218,6 +239,23 @@ t.timeout(250).describe('#update()', function() {
 
     assert.match(db.data.core.teststatic.updater, /static/i)
     assert.match(db.data.core.teststatic.updater, /nothing/i)
+    let old = db.data.core.teststatic.updater
+    assert.ok(stubWrite.called)
+    assert.strictEqual(stubWrite.callCount, 1)
+    
+    await app.update()
+    assert.strictEqual(db.data.core.teststatic.updater, old)
+    assert.strictEqual(stubWrite.callCount, 1)
+
+    db.data.core.teststatic.updater = 'asdf'
+    
+    await app.update()
+    assert.strictEqual(db.data.core.teststatic.updater, old)
+    assert.strictEqual(stubWrite.callCount, 2)
+    
+    await app.update()
+    assert.strictEqual(db.data.core.teststatic.updater, old)
+    assert.strictEqual(stubWrite.callCount, 2)
   })
 
   t.test('multiple calls should be safe', async function() {
@@ -250,6 +288,9 @@ t.timeout(250).describe('#update()', function() {
     
     assert.strictEqual(app.updating, false)
     assert.strictEqual(err, assertError)
+    
+    assert.ok(stubWrite.called)
+    assert.ok(stubWrite.callCount >= 1)
     assert.match(db.data.core.testapp.updater, /check/i)
     assert.match(db.data.core.testapp.updater, /version/i)
     assert.match(db.data.core.testapp.updater, new RegExp(new Date().toISOString().split('T')[0]))
@@ -288,6 +329,8 @@ t.timeout(250).describe('#update()', function() {
     assert.ok(assertVersion.log.endsWith('\n'))
     assert.strictEqual(assertVersion.failtodownload, 1)
     
+    assert.ok(stubWrite.called)
+    assert.ok(stubWrite.callCount >= 2)
     assert.ok(stubFsMkdir.called)
     assert.match(stubFsMkdir.firstCall[0], /123456789/)
     assert.ok(stubFsMkdir.firstCall[1]?.recursive)
@@ -370,7 +413,6 @@ t.timeout(250).describe('#update()', function() {
     assert.strictEqual(app.updating, false)
     assert.strictEqual(stubExtract.firstCall[0], assertTarget)
 
-    assert.notOk(stubWrite.called)
     assert.match(db.data.core.testapp.updater, new RegExp('extracting[^.]+file\.7z', 'i'))
     assert.match(db.data.core.testapp.updater, new RegExp(assertError.message))
     
@@ -379,6 +421,8 @@ t.timeout(250).describe('#update()', function() {
     assert.ok(stubFsRm.firstCall[1]?.recursive)
     assert.ok(stubFsRm.firstCall[1]?.force)
     
+    assert.ok(stubWrite.called)
+    assert.ok(stubWrite.callCount >= 3)
     assert.strictEqual(db.data.core.testapp.versions.length, 1)
     let version = db.data.core.testapp.versions[0]
     assert.ok(version.log)
@@ -504,7 +548,6 @@ t.timeout(250).describe('#update()', function() {
     const assertTargetCheck = util.getPathFromRoot('./testapp/123456789/')
     provider.getLatestVersion.resolves(assertVersion)
     assert.strictEqual(db.data.core.testapp.versions.length, 0)
-    assert.notOk(stubWrite.called)
 
     stubExtract.returnWith(function(target, stream) {
       stream(assertExtractText)
@@ -533,6 +576,8 @@ t.timeout(250).describe('#update()', function() {
       assert.notStrictEqual(stubFsRm.getCall(i)[0], assertTargetCheck)
     }
     
+    assert.ok(stubWrite.called)
+    assert.ok(stubWrite.callCount >= 4)
     assert.match(db.data.core.testapp.updater, /npm/i)
     assert.match(db.data.core.testapp.updater, /install/i)
     assert.strictEqual(db.data.core.testapp.versions.length, 1)
@@ -571,6 +616,9 @@ t.timeout(250).describe('#update()', function() {
     assert.strictEqual(db.data.core.testapp.versions.length, 1)
     assert.strictEqual(db.data.core.testapp.versions[0], assertVersion)
     assert.ok(assertVersion.log)
+    assert.ok(stubWrite.callCount >= 4)
+    assert.strictEqual(assertVersion.installed, true)
+    assert.strictEqual(assertVersion.stable, 0)
     assert.match(assertVersion.log, /found/i)
     assert.match(assertVersion.log, new RegExp(assertVersion.version))
     assert.match(assertVersion.log, /downloading/i)
@@ -582,8 +630,9 @@ t.timeout(250).describe('#update()', function() {
   t.test('should update existing version if found', async function() {
     const assertNewLink = 'THE last pain'
     const assertNewFilename = 'The place of hope.7z'
+    const assertStable = 100
     const oldLog = 'The Smell of Sea\n'
-    const assertVersion = { version: '123456789', link: 'httplinkhere', filename: 'test.7z', log: oldLog }
+    const assertVersion = { version: '123456789', link: 'httplinkhere', filename: 'test.7z', log: oldLog, stable: assertStable }
     
     assertVersion.id = assertVersion.version
     db.upsert(db.data.core.testapp.versions, assertVersion)
@@ -593,11 +642,15 @@ t.timeout(250).describe('#update()', function() {
 
     await app.update()
     
+    assert.ok(assertVersion.log)
+    assert.ok(stubWrite.callCount >= 4)
     assert.strictEqual(app.updating, false)
     assert.strictEqual(db.data.core.testapp.versions.length, 1)
     assert.strictEqual(db.data.core.testapp.versions[0], assertVersion)
+    assert.strictEqual(assertVersion.stable, assertStable)
     assert.ok(assertVersion.log)
     assert.ok(assertVersion.log.startsWith(oldLog))
+    assert.strictEqual(assertVersion.installed, true)
     assert.match(assertVersion.log, /found/i)
     assert.match(assertVersion.log, new RegExp(assertVersion.version))
     assert.match(assertVersion.log, /downloading/i)
@@ -616,6 +669,28 @@ t.timeout(250).describe('#update()', function() {
 
     await app.update()
     
+    assert.ok(stubWrite.callCount >= 1)
+    assert.strictEqual(app.updating, false)
+    assert.notOk(provider.downloadVersion.called)
+    assert.match(db.data.core.testapp.updater, /already/i)
+    assert.match(db.data.core.testapp.updater, /nothing/i)
+  })
+
+  t.test('should do nothing if installed version is found', async function() {
+    const assertError = new Error('should not be seen')
+    const assertVersion = { version: '999.888.777.666', filename: 'test.7z' }
+    provider.getLatestVersion.resolves(assertVersion)
+    provider.downloadVersion.rejects(assertError)
+    db.data.core.testapp.updater = ''
+
+    db.upsert(db.data.core.testapp.versions, { id: '111.111.111.111', installed: true })
+    db.upsert(db.data.core.testapp.versions, { id: '222.222.222.222', installed: true })
+    db.upsert(db.data.core.testapp.versions, { id: '999.888.777.666', installed: true })
+    db.upsert(db.data.core.testapp.versions, { id: '333.333.333.333', installed: true })
+
+    await app.update()
+    
+    assert.ok(stubWrite.callCount >= 1)
     assert.strictEqual(app.updating, false)
     assert.notOk(provider.downloadVersion.called)
     assert.match(db.data.core.testapp.updater, /already/i)
@@ -632,6 +707,7 @@ t.timeout(250).describe('#update()', function() {
 
     await app.update()
     
+    assert.ok(stubWrite.callCount >= 1)
     assert.strictEqual(app.updating, false)
     assert.notOk(provider.downloadVersion.called)
     assert.match(db.data.core.testapp.updater, /many/i)
@@ -649,6 +725,7 @@ t.timeout(250).describe('#update()', function() {
 
     await app.update()
     
+    assert.ok(stubWrite.callCount >= 1)
     assert.strictEqual(app.updating, false)
     assert.notOk(provider.downloadVersion.called)
     assert.match(db.data.core.testapp.updater, /many/i)
@@ -656,3 +733,55 @@ t.timeout(250).describe('#update()', function() {
     assert.match(db.data.core.testapp.updater, /skip/i)
   })
 })
+
+t.timeout(250).describe('#registerModule()', function() {
+  const assertAppName = 'testappregister'
+  let db
+  let app
+  
+  t.beforeEach(function() {
+    return lowdb({ test: { } }, logger, null).then(function(res) {
+      db = res
+      let provider = new StaticProvider()
+      app = new Application(util, db, provider, assertAppName)
+    })
+  })
+
+  t.test('should fail if not an object with start', function() {
+    let tests = [
+      [1, 'number'],
+      [0, 'empty number'],
+      ['text', 'string'],
+      ['', 'empty string'],
+      [{}, 'empty object'],
+      [[], 'array'],
+      [{ a: 1 }, 'non-empty object'],
+    ]
+
+    tests.forEach(function(check) {
+      assert.throws(function() {
+        app.registerModule(check[0])
+      }, function(err) {
+        assert.match(err.message, /registerModule/i)
+        assert.match(err.message, /function/i)
+        assert.match(err.message, /start/i)
+        assert.match(err.message, new RegExp(assertAppName, 'i'))
+        return true
+      }, `should fail if called with ${check[1]}`)
+    })
+  })
+
+  t.test('should otherwise succeed if object has function start', function() {
+    const assertFunction = function() {}
+    const assertModule = { start: assertFunction }
+
+    app.registerModule(assertModule)
+
+    assert.strictEqual(app.module, assertModule)
+
+    app.registerModule(assertFunction)
+    
+    assert.notStrictEqual(app.module, assertModule)
+    assert.deepStrictEqual(app.module, assertModule)
+  })
+})

test/db.test.mjs

@@ -151,7 +151,7 @@ t.test('Should support reading from db', async function() {
 })
 
 t.test('should throw if unable to write to file', function() {
-  return assert.isRejected(lowdb({}, logger, '../test'))
+  return assert.isRejected(lowdb({}, logger, util.getPathFromRoot('../test')))
 })
 
 t.test('should have basic database-like functions defined', async function() {
@@ -285,3 +285,22 @@ t.test('#upsert() should work properly', async function() {
   assert.strictEqual(db.data.test.items[0].id, '1234')
   assert.strictEqual(db.data.test.items[0].text, '2')
 })
+
+
+t.test('#upsertFirst() should work properly', async function() {
+  let db = await lowdb({}, logger, null)
+  db.data.test = {
+    items: []
+  }
+
+  db.upsertFirst(db.data.test.items, { id: '1234', text: '1' })
+  db.upsertFirst(db.data.test.items, { id: '1234', text: '2' })
+  db.upsertFirst(db.data.test.items, { id: '1', text: '3' })
+  db.upsertFirst(db.data.test.items, { id: '2', text: '4' })
+
+  assert.strictEqual(db.data.test.items.length, 3)
+  assert.strictEqual(db.data.test.items[2].id, '1234')
+  assert.strictEqual(db.data.test.items[2].text, '2')
+  assert.strictEqual(db.data.test.items[1].text, '3')
+  assert.strictEqual(db.data.test.items[0].text, '4')
+})

test/exampleindex.mjs

@@ -0,0 +1,17 @@
+export function start(db, log, core, http, port) {
+  const server = http.createServer(function (req, res) {
+    res.writeHead(200);
+    res.end(JSON.stringify({ version: 'exampleindex' }))
+  })
+
+  return new Promise(function(res, rej) {
+    server.listen(port || 4000, '0.0.0.0', function(err) {
+      if (err) {
+        return rej(err)
+      }
+      log.event.info(`Server is listening on ${port} serving package ${staticPackage}`)
+      log.info(`Server is listening on ${port} serving package ${staticPackage}`)
+      res()
+    })
+  })
+}

test/util.test.mjs

@@ -107,6 +107,45 @@ t.describe('#getApplications()', function() {
     assert.deepStrictEqual(util.getAppNames({ app: { provider: {}, port: 1234 } }), [])
     assert.deepStrictEqual(util.getAppNames({ app: { provider: 1234, port: 1234 } }), [])
   })
+
+  t.test('should fail to find if https is defined but not a boolean', function() {
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: null } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: false } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: true } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: 'asdf' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: '1234' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: 0 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: [] } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, https: {} } }), [])
+  })
+
+  t.test('should fail to find if updateEvery is defined but not a valid number', function() {
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: null } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: 5 } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: 1000 } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: 'asdf' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: '1234' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: 0 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: -5 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: [] } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, updateEvery: {} } }), [])
+  })
+
+  t.test('should fail to find if waitUntilFail is defined but not a valid number', function() {
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: null } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: 5 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: 15 } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: 1000 } }), ['app'])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: 'asdf' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: '1234' } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: 0 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: -5 } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: [] } }), [])
+    assert.deepStrictEqual(util.getAppNames({ app: { provider: 'asdf', port: 1234, waitUntilFail: {} } }), [])
+  })
 })
 
 t.describe('#verifyConfig()', function() {