Add a deprecation notice when ko:// is not specified.

Related: ko-build#158

README.md

@@ -35,8 +35,8 @@ paths like `github.com/google/ko/cmd`.
 
 **One of the goals of `ko` is to make containers invisible infrastructure.**
 Simply replace image references in your Kubernetes yaml with the import path for
-your Go binary, and `ko` will handle containerizing and publishing that
-container image as needed.
+your Go binary prefixed with `ko://`, and `ko` will handle containerizing and
+publishing that container image as needed.
 
 For example, you might use the following in a Kubernetes `Deployment` resource:
 
@@ -58,26 +58,19 @@ spec:
  containers:
  - name: hello-world
  # This is the import path for the Go binary to build and run.
- image: github.com/mattmoor/examples/http/cmd/helloworld
+ image: ko://github.com/mattmoor/examples/http/cmd/helloworld
  ports:
  - containerPort: 8080
 ```
 
-### Determining supported import paths
+### What gets built?
 
-Similar to other tooling in the Go ecosystem, `ko` expects to execute in the
-context of your `$GOPATH`. This is used to determine what package(s) `ko`
-is expected to build.
+`ko` will attempt to containerize and build any string within the yaml prefixed
+with `ko://`.
 
-Suppose `GOPATH` is `~/gopath` and the current directory is
-`~/gopath/src/github.com/mattmoor/examples`. `ko` will deduce the base import
-path to be `github.com/mattmoor/examples`, and any references to subpackages
-of this will be built, containerized and published.
+The legacy behavior of detecting import paths is deprecated and will be removed
+in a coming release.
 
-For example, any of the following would be matched:
-* `github.com/mattmoor/examples`
-* `github.com/mattmoor/examples/cmd/foo`
-* `github.com/mattmoor/examples/bar`
 
 ### Results
 

cmd/ko/test/test.yaml

@@ -15,10 +15,8 @@ apiVersion: v1
 kind: Pod
 metadata:
  name: kodata
- annotations:
- sidecar.istio.io/inject: "false"
 spec:
  containers:
  - name: obiwan
- image: github.com/google/ko/cmd/ko/test
+ image: ko://github.com/google/ko/cmd/ko/test
  restartPolicy: Never

pkg/build/gobuild.go

@@ -165,6 +165,20 @@ func NewGo(options ...Option) (Interface, error) {
  return gbo.Open()
 }
 
+const Deprecation158 = `NOTICE!
+-----------------------------------------------------------------
+We will start requiring ko:// in a coming release. Please prefix
+the following import path for things to continue working:
+
+ %s
+
+For more information see:
+
+ https:/google/ko/issues/158
+
+-----------------------------------------------------------------
+`
+
 // IsSupportedReference implements build.Interface
 //
 // Only valid importpaths that provide commands (i.e., are "package main") are
@@ -177,6 +191,9 @@ func (g *gobuild) IsSupportedReference(s string) bool {
  }
  return false
  } else if p.IsCommand() {
+ if !ref.IsStrict() {
+ log.Printf(Deprecation158, s)
+ }
  return true
  } else if ref.IsStrict() {
  log.Fatalf(`%q does not have "package main"`, ref.String())

pkg/commands/publisher.go

@@ -18,6 +18,7 @@ import (
  "context"
  "fmt"
  gb "go/build"
+ "strings"
 
  "github.com/google/go-containerregistry/pkg/name"
  "github.com/google/ko/pkg/build"
@@ -50,6 +51,9 @@ func publishImages(ctx context.Context, importpaths []string, pub publish.Interf
  return nil, err
  }
  }
+ if !strings.HasPrefix(importpath, build.StrictScheme) {
+ importpath = build.StrictScheme + importpath
+ }
 
  if !b.IsSupportedReference(importpath) {
  return nil, fmt.Errorf("importpath %q is not supported", importpath)