feat(config): Add env and file support to Controller description

CHANGELOG.md

@@ -5,7 +5,9 @@ Canonical reference for changes, improvements, and bugfixes for Boundary.
 ## Next
 
 ### New and Improved
-
+* config: The `description` field for controllers now supports being set
+  from environment variables or a file on disk
+  ([PR](https://github.com/hashicorp/boundary/pull/1766))
 * config: Add support for go-sockaddr templates to Worker and Controller
   addresses. ([PR](https://github.com/hashicorp/boundary/pull/1731))
 * host: Plugin-based host catalogs will now schedule updates for all

internal/cmd/config/config.go

@@ -308,6 +308,13 @@ func Parse(d string) (*Config, error) {
 		if !strutil.Printable(result.Controller.Name) {
 			return nil, errors.New("Controller name contains non-printable characters")
 		}
+		result.Controller.Description, err = parseutil.ParsePath(result.Controller.Description)
+		if err != nil && !errors.Is(err, parseutil.ErrNotAUrl) {
+			return nil, fmt.Errorf("Error parsing controller description: %w", err)
+		}
+		if !strutil.Printable(result.Controller.Description) {
+			return nil, errors.New("Controller description contains non-printable characters")
+		}
 		if result.Controller.AuthTokenTimeToLive != "" {
 			t, err := parseutil.ParseDurationSecond(result.Controller.AuthTokenTimeToLive)
 			if err != nil {

internal/cmd/config/config_test.go

@@ -524,3 +524,57 @@ func TestController_EventingConfig(t *testing.T) {
 		})
 	}
 }
+
+func TestControllerDescription(t *testing.T) {
+	tests := []struct {
+		name           string
+		in             string
+		envDescription string
+		expDescription string
+		expErr         bool
+		expErrStr      string
+	}{
+		{
+			name: "Valid controller description from env var",
+			in: `
+			controller {
+				description = "env://CONTROLLER_DESCRIPTION"
+			}`,
+			envDescription: "Test controller description",
+			expDescription: "Test controller description",
+			expErr:         false,
+		}, {
+			name: "Invalid controller description from env var",
+			in: `
+			controller {
+				description = "\uTest controller description"
+			}`,
+			expErr:    true,
+			expErrStr: "At 3:22: illegal char escape",
+		},{
+			name: "Not a URL, non-printable description",
+			in: `
+			controller {
+				description = "\x00" 
+			}`,
+			expErr: true,
+			expErrStr: "Controller description contains non-printable characters",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Setenv("CONTROLLER_DESCRIPTION", tt.envDescription)
+			c, err := Parse(tt.in)
+			if tt.expErr {
+				require.EqualError(t, err, tt.expErrStr)
+				require.Nil(t, c)
+				return
+			}
+
+			require.NoError(t, err)
+			require.NotNil(t, c)
+			require.NotNil(t, c.Controller)
+			require.Equal(t, tt.expDescription, c.Controller.Description)
+		})
+	}
+}

website/content/docs/configuration/controller.mdx

@@ -25,7 +25,9 @@ controller {
   (file://) from which an name will be read; or an env var (env://) from which
   the name will be read.
 
-- `description` - Specifies a friendly description of this controller.
+- `description` - Specifies a friendly description of this controller. This value can be a direct description string,
+can refer to a file on disk (file://) from which a description will be read; or an env var (env://) from which the
+description will be read.
 
 - `database` - Configuration block with two valid parameters for connecting to Postgres: