Repository: apigee/registry (go)

Issue:
Registry tool: --config option fails to accept file name arguments
The registry tool accepts a `--config` argument that is documented as accepting a path to a file.

```
 registry
A command-line tool for working with the API Registry

Usage:
  registry [command]

Available Commands:
  annotate    Annotate resources in the API Registry
  apply       Apply YAML to the API Registry
  auth        Manage client authentication to the API Registry
  check       Check entities in the API Registry
  completion  Generate the autocompletion script for the specified shell
  compute     Compute properties of resources in the API Registry
  config      Maintain properties in the active configuration
  delete      Delete resources from the API Registry
  diff        Compare resources in the API Registry
  export      Export resources from the API Registry
  get         Get resources from the API Registry
  help        Help about any command
  label       Label resources in the API Registry
  resolve     Resolve dependencies by performing actions in a specified manifest
  rpc         Make direct calls to RPC methods
  upload      Upload information to the API Registry

Available Plugins:
  bigquery
  connect
  experimental
  index

Flags:
      --address string             the server and port of the Registry API (eg. localhost:8080)
  -c, --config string              name of a configuration profile or path to config file
  -h, --help                       help for registry
      --registry.address string    the server and port of the Registry API (eg. localhost:8080)
      --registry.insecure          if specified, client connects via http (not https)
      --registry.location string   the API Registry location
      --registry.project string    the API Registry project
      --registry.token string      the token to use for authorization to the API Registry
  -v, --version                    version for registry

Use "registry [command] --help" for more information about a command.

Need more help?
https://github.com/apigee/registry/wiki
```

However, in practice, this doesn't work:
```
$ registry --config ~/.config/registry/local config list
Usage:
registry config list [flags]
...
Error: cannot read config: "/home/timburks/.config/registry/local" must not include a path
Run 'registry --help' for usage.
```

Pull request:
Fix problems with reading config files using `--config`
Fixes #1228.

Patch:
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 9351c87..3fd7f53 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -37,7 +37,7 @@ var (
 	// `cmd.PersistentFlags().AddFlagSet(connection.Flags)`
 	Flags *pflag.FlagSet = CreateFlagSet()
 
-	// Directory is $HOME/config/registry
+	// Directory is $HOME/.config/registry
 	Directory             string
 	ErrCannotDeleteActive = fmt.Errorf("cannot delete active configuration")
 	ErrReservedConfigName = fmt.Errorf("%q is reserved", ActivePointerFilename)
@@ -100,10 +100,6 @@ func ValidateName(name string) error {
 	if name == ActivePointerFilename {
 		return ErrReservedConfigName
 	}
-
-	if dir, _ := filepath.Split(name); dir != "" {
-		return fmt.Errorf("%q must not include a path", name)
-	}
 	return nil
 }
 
@@ -199,9 +195,10 @@ func ReadValid(name string) (c Configuration, err error) {
 }
 
 // Read loads a Configuration from yaml file matching `name`. If name
-// contains a path, the file will be read from that path, otherwise
-// the path is assumed as: ~/.config/registry. Does a simple read from the
-// file: does not bind to env vars or flags, resolve, or validate.
+// contains a path or refers to a local file, the file will be read
+// using name, otherwise the path is assumed as: ~/.config/registry.
+// Does a simple read from the file: does not bind to env vars or flags,
+// resolve, or validate.
 // See also: ReadValid()
 func Read(name string) (c Configuration, err error) {
 	if err = ValidateName(name); err != nil {
@@ -210,7 +207,11 @@ func Read(name string) (c Configuration, err error) {
 
 	dir, file := filepath.Split(name)
 	if dir == "" {
-		name = filepath.Join(Directory, file)
+		// If name refers to a local file, preferentially read the local file.
+		// Otherwise assume name refers to a file in the config directory.
+		if info, err := os.Stat(file); errors.Is(err, os.ErrNotExist) || info.IsDir() {
+			name = filepath.Join(Directory, file)
+		}
 	}
 	var r io.Reader
 	if r, err = os.Open(name); err != nil {


Test patch:
diff --git a/pkg/config/configuration_test.go b/pkg/config/configuration_test.go
index 3280487..a20f163 100644
--- a/pkg/config/configuration_test.go
+++ b/pkg/config/configuration_test.go
@@ -15,6 +15,7 @@
 package config_test
 
 import (
+	"log"
 	"os"
 	"path"
 	"path/filepath"
@@ -24,6 +25,7 @@ import (
 	"github.com/apigee/registry/pkg/config"
 	"github.com/apigee/registry/pkg/config/test"
 	"github.com/google/go-cmp/cmp"
+	"gopkg.in/yaml.v2"
 )
 
 func TestMissingDirectory(t *testing.T) {
@@ -476,3 +478,40 @@ func TestResolve(t *testing.T) {
 		t.Errorf("want: %s, got: %s", "hello", c.Registry.Token)
 	}
 }
+
+func TestReadExternalFile(t *testing.T) {
+	c := config.Configuration{
+		Registry: config.Registry{Address: "example.com:443"},
+	}
+	bytes, err := yaml.Marshal(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+	f, err := os.CreateTemp(".", "tmpfile-")
+	if err != nil {
+		log.Fatal(err)
+	}
+	if _, err = f.Write(bytes); err != nil {
+		log.Fatal(err)
+	}
+	if err = f.Close(); err != nil {
+		log.Fatal(err)
+	}
+	defer os.Remove(f.Name())
+	// Verify that we can read a file using its full path name.
+	c2, err := config.Read(f.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c2.Registry.Address != c.Registry.Address {
+		t.Errorf("want: %s, got: %s", c2.Registry.Address, c.Registry.Address)
+	}
+	// Verify that we can read a local file using its base name.
+	c3, err := config.Read(filepath.Base(f.Name()))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c3.Registry.Address != c.Registry.Address {
+		t.Errorf("want: %s, got: %s", c3.Registry.Address, c.Registry.Address)
+	}
+}