feat: added --hot-reload flag to dev & deploy

Hot reloading is now only enabled for the services explicitly specified
via the dev & deploy commands' new --hot-reload option.

When this option is used, the respective commands are run in watch mode
(i.e. assume the -w/--watch flag).

Also: Started using HotReloadScheduler to prevent possible race
conditions when multiple hot reload operations are in flight for the
same module (something that HotReloadScheduler prevents by design).

docs/reference/commands.md

@@ -210,11 +210,12 @@ Deploy service(s) to your environment.
 
     Examples:
 
-        garden deploy              # deploy all modules in the project
-        garden deploy my-service   # only deploy my-service
-        garden deploy --force      # force re-deploy of modules, even if they're already deployed
-        garden deploy --watch      # watch for changes to code
-        garden deploy --env stage  # deploy your services to an environment called stage
+        garden deploy                         # deploy all modules in the project
+        garden deploy my-service              # only deploy my-service
+        garden deploy --force                 # force re-deploy of modules, even if they're already deployed
+        garden deploy --watch                 # watch for changes to code
+        garden deploy --hot-reload=my-service # deploys all services, with hot reloading enabled for my-service
+        garden deploy --env stage             # deploy your services to an environment called stage
 
 
 ##### Usage
@@ -225,7 +226,7 @@ Deploy service(s) to your environment.
 
 | Argument | Required | Description |
 | -------- | -------- | ----------- |
-  | `service` | No | The name of the service(s) to deploy (skip to deploy all services). Use comma as separator to specify multiple services.
+  | `service` | No | The name(s) of the service(s) to deploy (skip to deploy all services). Use comma as separator to specify multiple services.
 
 ##### Options
 
@@ -234,6 +235,7 @@ Deploy service(s) to your environment.
   | `--force` |  | boolean | Force redeploy of service(s).
   | `--force-build` |  | boolean | Force rebuild of module(s).
   | `--watch` | `-w` | boolean | Watch for changes in module(s) and auto-deploy.
+  | `--hot-reload` |  | array:string | The name(s) of the service(s) to deploy with hot reloading enabled. Use comma as separator to specify multiple services. When this option is used, the command is run in watch mode (i.e. implicitly assumes the --watch/-w flag).
 
 ### garden dev
 
@@ -247,11 +249,18 @@ Starts the garden development console.
     Examples:
 
         garden dev
+        garden dev --hot-reload=foo-service,bar-service # enable hot reloading for foo-service and bar-service
 
 
 ##### Usage
 
-    garden dev 
+    garden dev [options]
+
+##### Options
+
+| Argument | Alias | Type | Description |
+| -------- | ----- | ---- | ----------- |
+  | `--hot-reload` |  | array:string | The name(s) of the service(s) to deploy with hot reloading enabled. Use comma as separator to specify multiple services.
 
 ### garden exec
 

docs/reference/config.md

@@ -176,7 +176,7 @@ project:
         {}
 
       # Valid RFC1035/RFC1123 (DNS) label (may contain lowercase letters, numbers and dashes, must
-      # start with a letter, and cannot end with a dash) and additionally cannot contain
+      # start with a letter,and cannot end with a dash) and additionally cannot contain
       # consecutive dashes or be longer than 63 characters.
       #
       # Required.
@@ -452,7 +452,7 @@ module:
     #
     # Optional.
     - # Valid RFC1035/RFC1123 (DNS) label (may contain lowercase letters, numbers and dashes, must
-      # start with a letter, and cannot end with a dash) and additionally cannot contain
+      # start with a letter,and cannot end with a dash) and additionally cannot contain
       # consecutive dashes or be longer than 63 characters.
       #
       # Required.
@@ -463,7 +463,7 @@ module:
       # Optional.
       dependencies: 
         # Valid RFC1035/RFC1123 (DNS) label (may contain lowercase letters, numbers and dashes,
-        # must start with a letter, and cannot end with a dash) and additionally cannot contain
+        # must start with a letter,and cannot end with a dash) and additionally cannot contain
         # consecutive dashes or be longer than 63 characters.
         #
         # Optional.

examples/hello-world/.garden/local-config.yml

@@ -1,4 +1,5 @@
 kubernetes:
-  username: hello
   previous-usernames:
     - hello
+linkedModuleSources: []
+linkedProjectSources: []

examples/hot-reload/garden.yml

@@ -3,7 +3,6 @@ project:
   environmentDefaults:
     providers:
       - name: container
-      - name: npm-package
   environments:
     - name: local
       providers:

examples/hot-reload/node-service/app.js

@@ -0,0 +1,14 @@
+const express = require("express")
+
+const app = express()
+
+app.get("/hello", (req, res) => {
+  res.json({message: "Hello from Node!"})
+})
+
+// This is the path GAE uses for health checks
+app.get("/_ah/health", (req, res) => {
+  res.sendStatus(200)
+})
+
+module.exports = { app }

examples/hot-reload/node-service/garden.yml

@@ -0,0 +1,21 @@
+module:
+  description: Node greeting service
+  name: node-service
+  type: container
+  hotReload:
+    sync:
+      - target: /app/
+  services:
+    - name: node-service
+      command: [npm, start]
+      hotReloadCommand: [npm, run, dev]
+      ports:
+        - name: http
+          containerPort: 8080
+      ingresses:
+        - path: /hello
+          port: http
+      healthCheck:
+        httpGet:
+          path: /_ah/health
+          port: http

garden-service/.gitignore

@@ -8,5 +8,6 @@ static/**/.garden-version
 support/**/*.js
 support/**/*.map
 support/**/*.d.ts
-test/**/*.js
-test/**/*.map
+test/*.js
+test/src/**/*.js
+test/integ/**/*.js

garden-service/src/actions.ts

@@ -67,7 +67,7 @@ import { mapValues, values, keyBy, omit } from "lodash"
 import { Omit } from "./util/util"
 import { RuntimeContext } from "./types/service"
 import { processServices, ProcessResults } from "./process"
-import { getDeployTasks } from "./tasks/deploy"
+import { getDeployTasks } from "./tasks/helpers"
 import { LogEntry } from "./logger/log-entry"
 import { createPluginContext } from "./plugin-context"
 import { CleanupEnvironmentParams } from "./types/plugin/params"
@@ -229,7 +229,9 @@ export class ActionHelper implements TypeGuard {
 
   async hotReload<T extends Module>(params: ModuleActionHelperParams<HotReloadParams<T>>)
     : Promise<HotReloadResult> {
-    return this.callModuleHandler(({ params, actionType: "hotReload" }))
+    return this.garden.hotReload(params.module.name, async () => {
+      return this.callModuleHandler(({ params, actionType: "hotReload" }))
+    })
   }
 
   async testModule<T extends Module>(params: ModuleActionHelperParams<TestModuleParams<T>>): Promise<TestResult> {
@@ -333,9 +335,9 @@ export class ActionHelper implements TypeGuard {
         garden: this.garden,
         module,
         serviceNames,
+        hotReloadServiceNames: [],
         force,
         forceBuild,
-        includeDependants: false,
       }),
     })
   }

garden-service/src/commands/build.ts

@@ -20,7 +20,7 @@ import dedent = require("dedent")
 import { processModules } from "../process"
 import { computeAutoReloadDependants, withDependants } from "../watch"
 import { Module } from "../types/module"
-import { hotReloadAndLog } from "./deploy"
+import { hotReloadAndLog } from "./helpers"
 
 const buildArguments = {
   module: new StringsParameter({
@@ -73,8 +73,9 @@ export class BuildCommand extends Command<BuildArguments, BuildOptions> {
       watch: opts.watch,
       handler: async (module) => [new BuildTask({ garden, module, force: opts.force })],
       changeHandler: async (module: Module) => {
+
         if (module.spec.hotReload) {
-          hotReloadAndLog(module, garden)
+          await hotReloadAndLog(garden, module)
         }
 
         return (await withDependants(garden, [module], autoReloadDependants))

garden-service/src/commands/deploy.ts

@@ -6,7 +6,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-import chalk from "chalk"
+import deline = require("deline")
 import {
   BooleanParameter,
   Command,
@@ -15,27 +15,29 @@ import {
   handleTaskResults,
   StringsParameter,
 } from "./base"
-import { Garden } from "../garden"
-import { Module } from "../types/module"
-import { getDeployTasks } from "../tasks/deploy"
+import { hotReloadAndLog, validateHotReloadOpt } from "./helpers"
+import { getDeployTasks, getTasksForHotReload, getHotReloadModuleNames } from "../tasks/helpers"
 import { TaskResults } from "../task-graph"
 import { processServices } from "../process"
 import { getNames } from "../util/util"
-import { prepareRuntimeContext } from "../types/service"
-import { uniq } from "lodash"
-import { flatten } from "underscore"
 
 const deployArgs = {
   service: new StringsParameter({
-    help: "The name of the service(s) to deploy (skip to deploy all services). " +
-      "Use comma as separator to specify multiple services.",
+    help: deline`The name(s) of the service(s) to deploy (skip to deploy all services).
+      Use comma as separator to specify multiple services.`,
   }),
 }
 
 const deployOpts = {
   force: new BooleanParameter({ help: "Force redeploy of service(s)." }),
   "force-build": new BooleanParameter({ help: "Force rebuild of module(s)." }),
   watch: new BooleanParameter({ help: "Watch for changes in module(s) and auto-deploy.", alias: "w" }),
+  "hot-reload": new StringsParameter({
+    help: deline`The name(s) of the service(s) to deploy with hot reloading enabled.
+      Use comma as separator to specify multiple services. When this option is used,
+      the command is run in watch mode (i.e. implicitly assumes the --watch/-w flag).
+    `,
+  }),
 }
 
 type Args = typeof deployArgs
@@ -54,11 +56,12 @@ export class DeployCommand extends Command<Args, Opts> {
 
     Examples:
 
-        garden deploy              # deploy all modules in the project
-        garden deploy my-service   # only deploy my-service
-        garden deploy --force      # force re-deploy of modules, even if they're already deployed
-        garden deploy --watch      # watch for changes to code
-        garden deploy --env stage  # deploy your services to an environment called stage
+        garden deploy                         # deploy all modules in the project
+        garden deploy my-service              # only deploy my-service
+        garden deploy --force                 # force re-deploy of modules, even if they're already deployed
+        garden deploy --watch                 # watch for changes to code
+        garden deploy --hot-reload=my-service # deploys all services, with hot reloading enabled for my-service
+        garden deploy --env stage             # deploy your services to an environment called stage
   `
 
   arguments = deployArgs
@@ -69,10 +72,23 @@ export class DeployCommand extends Command<Args, Opts> {
     const serviceNames = getNames(services)
 
     if (services.length === 0) {
-      garden.log.warn({ msg: "No services found. Aborting." })
+      garden.log.error({ msg: "No services found. Aborting." })
       return { result: {} }
     }
 
+    let watch
+    const hotReloadServiceNames = opts["hot-reload"] || []
+    const hotReloadModuleNames = await getHotReloadModuleNames(garden, hotReloadServiceNames)
+
+    if (opts["hot-reload"]) {
+      if (!validateHotReloadOpt(garden, hotReloadServiceNames)) {
+        return { result: {} }
+      }
+      watch = true
+    } else {
+      watch = opts.watch
+    }
+
     garden.log.header({ emoji: "rocket", command: "Deploy" })
 
     // TODO: make this a task
@@ -81,64 +97,28 @@ export class DeployCommand extends Command<Args, Opts> {
     const results = await processServices({
       garden,
       services,
-      watch: opts.watch,
+      watch,
       handler: async (module) => getDeployTasks({
         garden,
         module,
         serviceNames,
+        watch,
+        hotReloadServiceNames,
         force: opts.force,
         forceBuild: opts["force-build"],
-        watch: opts.watch,
-        includeDependants: false,
       }),
       changeHandler: async (module) => {
-
-        const hotReload = !!module.spec.hotReload
-
-        if (hotReload) {
-          hotReloadAndLog(module, garden)
+        if (hotReloadModuleNames.has(module.name)) {
+          await hotReloadAndLog(garden, module)
+          return getTasksForHotReload({ garden, module, hotReloadServiceNames, serviceNames })
+        } else {
+          return getDeployTasks({
+            garden, module, serviceNames, hotReloadServiceNames, force: true, forceBuild: true, watch: true,
+          })
         }
-
-        return getDeployTasks({
-          garden,
-          module,
-          serviceNames,
-          force: true,
-          forceBuild: true,
-          watch: true,
-          includeDependants: true,
-          skipDeployTaskForModule: hotReload,
-        })
-
       },
     })
 
     return handleTaskResults(garden, "deploy", results)
   }
 }
-
-export async function hotReloadAndLog(module: Module, garden: Garden) {
-
-  const logEntry = garden.log.info({
-    section: module.name,
-    msg: "Hot reloading",
-    status: "active",
-  })
-
-  const serviceDependencyNames = uniq(flatten(module.services.map(s => s.config.dependencies)))
-  const runtimeContext = await prepareRuntimeContext(garden, module, await garden.getServices(serviceDependencyNames))
-
-  try {
-    await garden.actions.hotReload({ module, runtimeContext })
-  } catch (err) {
-    logEntry.setError()
-    throw err
-  }
-
-  const msec = logEntry.getDuration(5) * 1000
-  logEntry.setSuccess({
-    msg: chalk.green(`Done (took ${msec} ms)`),
-    append: true,
-  })
-
-}