fix(k8s): hostPath is now relative to module source path

Previously we implicitly expected an absolute path. Now we explicitly
make it relative to the module path, but also support absolute paths.

Also added some docs, warning against the usage of hostPath.

docs/reference/module-types/container.md

@@ -813,10 +813,24 @@ The path where the volume should be mounted in the container.
 
 [services](#services) > [volumes](#servicesvolumes) > hostPath
 
+_NOTE: Usage of hostPath is generally discouraged, since it doesn't work reliably across different platforms
+and providers. Some providers may not support it at all._
+
+A local path or path on the node that's running the container, to mount in the container, relative to the
+module source path (or absolute).
+
 | Type     | Required |
 | -------- | -------- |
 | `string` | No       |
 
+Example:
+
+```yaml
+services:
+  - volumes:
+      - hostPath: "/some/dir"
+```
+
 ### `tests`
 
 A list of tests to run in the module.

docs/reference/module-types/maven-container.md

@@ -818,10 +818,24 @@ The path where the volume should be mounted in the container.
 
 [services](#services) > [volumes](#servicesvolumes) > hostPath
 
+_NOTE: Usage of hostPath is generally discouraged, since it doesn't work reliably across different platforms
+and providers. Some providers may not support it at all._
+
+A local path or path on the node that's running the container, to mount in the container, relative to the
+module source path (or absolute).
+
 | Type     | Required |
 | -------- | -------- |
 | `string` | No       |
 
+Example:
+
+```yaml
+services:
+  - volumes:
+      - hostPath: "/some/dir"
+```
+
 ### `tests`
 
 A list of tests to run in the module.

garden-service/src/plugins/container/config.ts

@@ -25,6 +25,7 @@ import { CommonServiceSpec, ServiceConfig, baseServiceSpecSchema } from "../../c
 import { baseTaskSpecSchema, BaseTaskSpec } from "../../config/task"
 import { baseTestSpecSchema, BaseTestSpec } from "../../config/test"
 import { joiStringMap } from "../../config/common"
+import { dedent } from "../../util/string"
 
 export const defaultContainerLimits: ServiceLimitSpec = {
   cpu: 1000,     // = 1000 millicpu = 1 CPU
@@ -285,10 +286,19 @@ const volumeSchema = joi.object()
       .required()
       .description("The name of the allocated volume."),
     containerPath: joi.string()
+      .posixPath()
       .required()
       .description("The path where the volume should be mounted in the container."),
     hostPath: joi.string()
-      .meta({ deprecated: true }),
+      .posixPath()
+      .description(dedent`
+        _NOTE: Usage of hostPath is generally discouraged, since it doesn't work reliably across different platforms
+        and providers. Some providers may not support it at all._
+
+        A local path or path on the node that's running the container, to mount in the container, relative to the
+        module source path (or absolute).
+      `)
+      .example("/some/dir"),
   })
 
 const serviceSchema = baseServiceSpecSchema

garden-service/src/plugins/kubernetes/container/deployment.ts

@@ -30,6 +30,7 @@ import { DeleteServiceParams } from "../../../types/plugin/service/deleteService
 import { millicpuToString, kilobytesToString, prepareEnvVars, workloadTypes } from "../util"
 import { gardenAnnotationKey } from "../../../util/string"
 import { RuntimeContext } from "../../../runtime-context"
+import { resolve } from "path"
 
 export const DEFAULT_CPU_REQUEST = "10m"
 export const DEFAULT_MEMORY_REQUEST = "64Mi"
@@ -288,7 +289,7 @@ export async function createWorkloadResource(
   }
 
   if (spec.volumes && spec.volumes.length) {
-    configureVolumes(deployment, container, spec)
+    configureVolumes(service.module, deployment, container, spec)
   }
 
   const ports = spec.ports
@@ -467,7 +468,7 @@ function configureHealthCheck(container, spec): void {
 
 }
 
-function configureVolumes(deployment, container, spec): void {
+function configureVolumes(module: ContainerModule, deployment, container, spec): void {
   const volumes: any[] = []
   const volumeMounts: any[] = []
 
@@ -492,12 +493,12 @@ function configureVolumes(deployment, container, spec): void {
       volumes.push({
         name: volumeName,
         hostPath: {
-          path: volume.hostPath,
+          path: resolve(module.path, volume.hostPath),
         },
       })
       volumeMounts.push({
         name: volumeName,
-        mountPath: volume.containerPath || volume.hostPath,
+        mountPath: volume.containerPath,
       })
     } else {
       throw new Error("Unsupported volume type: " + volumeType)

garden-service/src/plugins/local/local-docker-swarm.ts

@@ -20,6 +20,7 @@ import { DeployServiceParams } from "../../types/plugin/service/deployService"
 import { ExecInServiceParams } from "../../types/plugin/service/execInService"
 import { GetServiceStatusParams } from "../../types/plugin/service/getServiceStatus"
 import { EnvironmentStatus } from "../../types/plugin/provider/getEnvironmentStatus"
+import { resolve } from "path"
 
 // should this be configurable and/or global across providers?
 const DEPLOY_TIMEOUT = 30
@@ -64,7 +65,7 @@ export const gardenPlugin = createGardenPlugin({
           if (v.hostPath) {
             return {
               Type: "bind",
-              Source: v.hostPath,
+              Source: resolve(module.path, v.hostPath),
               Target: v.containerPath,
             }
           } else {