fix(build): ensure that exec modules are rebuilt on when garden is run

Prior to this commit, garden would skip building exec modules that had been built during a previous garden run, if none of the source files in the module changed.

While this is a good optimisation, it caused problems because staging would still happen, wiping out any previously built artifacts which other modules might have depended on.  Also, there is no way to guarantee/specify at the module level that there are no outside dependencies that aren't captured by the module's sources.

It is planned to properly support this in the future, but removing this optimisation for now.

garden-service/src/plugins/exec.ts

@@ -15,13 +15,12 @@ import { createGardenPlugin } from "../types/plugin/plugin"
 import { Module } from "../types/module"
 import { CommonServiceSpec } from "../config/service"
 import { BaseTestSpec, baseTestSpecSchema } from "../config/test"
-import { readModuleVersionFile, writeModuleVersionFile, ModuleVersion } from "../vcs/vcs"
+import { writeModuleVersionFile } from "../vcs/vcs"
 import { GARDEN_BUILD_VERSION_FILENAME } from "../constants"
 import { ModuleSpec, BaseBuildSpec, baseBuildSpecSchema, ModuleConfig } from "../config/module"
 import { BaseTaskSpec, baseTaskSpecSchema } from "../config/task"
 import { dedent } from "../util/string"
 import { ConfigureModuleParams, ConfigureModuleResult } from "../types/plugin/module/configure"
-import { GetBuildStatusParams, BuildStatus } from "../types/plugin/module/getBuildStatus"
 import { BuildModuleParams, BuildResult } from "../types/plugin/module/build"
 import { TestModuleParams } from "../types/plugin/module/testModule"
 import { TestResult } from "../types/plugin/module/getTestResult"
@@ -200,23 +199,6 @@ export async function configureExecModule({
   return { moduleConfig }
 }
 
-export async function getExecModuleBuildStatus({ module }: GetBuildStatusParams): Promise<BuildStatus> {
-  const buildVersionFilePath = join(module.buildMetadataPath, GARDEN_BUILD_VERSION_FILENAME)
-  let builtVersion: ModuleVersion | null = null
-
-  try {
-    builtVersion = await readModuleVersionFile(buildVersionFilePath)
-  } catch (_) {
-    // just ignore this error, can be caused by an outdated format
-  }
-
-  if (builtVersion && builtVersion.versionString === module.version.versionString) {
-    return { ready: true }
-  }
-
-  return { ready: false }
-}
-
 export async function buildExecModule({ module }: BuildModuleParams<ExecModule>): Promise<BuildResult> {
   const output: BuildResult = {}
   const { command } = module.spec.build
@@ -353,7 +335,6 @@ export const execPlugin = createGardenPlugin({
       }),
       handlers: {
         configure: configureExecModule,
-        getBuildStatus: getExecModuleBuildStatus,
         build: buildExecModule,
         runTask: runExecTask,
         testModule: testExecModule,

garden-service/test/unit/src/plugins/exec.ts

@@ -7,7 +7,7 @@ import { LogEntry } from "../../../../src/logger/log-entry"
 import { keyBy } from "lodash"
 import { getDataDir, makeTestModule, expectError } from "../../../helpers"
 import { TaskTask } from "../../../../src/tasks/task"
-import { writeModuleVersionFile, readModuleVersionFile } from "../../../../src/vcs/vcs"
+import { readModuleVersionFile } from "../../../../src/vcs/vcs"
 import { dataDir, makeTestGarden } from "../../../helpers"
 import { ModuleConfig } from "../../../../src/config/module"
 import { ConfigGraph } from "../../../../src/config-graph"
@@ -249,22 +249,6 @@ describe("exec plugin", () => {
     })
   })
 
-  describe("getBuildStatus", () => {
-    it("should read a build version file if it exists", async () => {
-      const module = await graph.getModule(moduleName)
-      const version = module.version
-      const buildMetadataPath = module.buildMetadataPath
-      const versionFilePath = join(buildMetadataPath, GARDEN_BUILD_VERSION_FILENAME)
-
-      await writeModuleVersionFile(versionFilePath, version)
-
-      const actions = await garden.getActionRouter()
-      const result = await actions.getBuildStatus({ log, module })
-
-      expect(result.ready).to.be.true
-    })
-  })
-
   describe("build", () => {
     it("should write a build version file after building", async () => {
       const module = await graph.getModule(moduleName)