rc: add options/info call to enumerate options

This also makes some fields in the Options block optional - these are
documented in rc.md

docs/content/rc.md

@@ -400,6 +400,76 @@ call and taken by the [options/set](#options-set) calls as well as the
 - `BandwidthSpec` - this will be set and returned as a string, eg
   "1M".
 
+### Option blocks {#option-blocks}
+
+The calls [options/info](#options-info) (for the main config) and
+[config/providers](#config-providers) (for the backend config) may be
+used to get information on the rclone configuration options. This can
+be used to build user interfaces for displaying and setting any rclone
+option.
+
+These consist of arrays of `Option` blocks. These have the following
+format. Each block describes a single option.
+
+| Field | Type | Optional | Description |
+|-------|------|----------|-------------|
+| Name       | string     | N | name of the option in snake_case |
+| FieldName  | string     | N | name of the field used in the rc - if blank use Name |
+| Help       | string     | N | help, started with a single sentence on a single line |
+| Groups     | string     | Y | groups this option belongs to - comma separated string for options classification |
+| Provider   | string     | Y | set to filter on provider |
+| Default    | any        | N | default value, if set (and not to nil or "") then Required does nothing |
+| Value      | any        | N | value to be set by flags |
+| Examples   | Examples   | Y | predefined values that can be selected from list (multiple-choice option) |
+| ShortOpt   | string     | Y | the short command line option for this |
+| Hide       | Visibility | N | if non zero, this option is hidden from the configurator or the command line |
+| Required   | bool       | N | this option is required, meaning value cannot be empty unless there is a default |
+| IsPassword | bool       | N | set if the option is a password |
+| NoPrefix   | bool       | N | set if the option for this should not use the backend prefix |
+| Advanced   | bool       | N | set if this is an advanced config option |
+| Exclusive  | bool       | N | set if the answer can only be one of the examples (empty string allowed unless Required or Default is set) |
+| Sensitive  | bool       | N | set if this option should be redacted when using `rclone config redacted` |
+
+An example of this might be the `--log-level` flag. Note that the
+`Name` of the option becomes the command line flag with `_` replaced
+with `-`.
+
+```
+{
+    "Advanced": false,
+    "Default": 5,
+    "DefaultStr": "NOTICE",
+    "Examples": [
+        {
+            "Help": "",
+            "Value": "EMERGENCY"
+        },
+        {
+            "Help": "",
+            "Value": "ALERT"
+        },
+        ...
+    ],
+    "Exclusive": true,
+    "FieldName": "LogLevel",
+    "Groups": "Logging",
+    "Help": "Log level DEBUG|INFO|NOTICE|ERROR",
+    "Hide": 0,
+    "IsPassword": false,
+    "Name": "log_level",
+    "NoPrefix": true,
+    "Required": true,
+    "Sensitive": false,
+    "Type": "LogLevel",
+    "Value": null,
+    "ValueStr": "NOTICE"
+},
+```
+
+Note that the `Help` may be multiple lines separated by `\n`. The
+first line will always be a short sentence and this is the sentence
+shown when running `rclone help flags`.
+
 ## Specifying remotes to work on
 
 Remotes are specified with the `fs=`, `srcFs=`, `dstFs=`
@@ -638,7 +708,12 @@ See the [config paths](/commands/rclone_config_paths/) command for more informat
 Returns a JSON object:
 - providers - array of objects
 
-See the [config providers](/commands/rclone_config_providers/) command for more information on the above.
+See the [config providers](/commands/rclone_config_providers/) command
+for more information on the above.
+
+Note that the Options blocks are in the same format as returned by
+"options/info". They are described in the
+[option blocks](#option-blocks) section.
 
 **Authentication is required for this call.**
 
@@ -1647,6 +1722,14 @@ set in _config then use options/config and for _filter use options/filter.
 This shows the internal names of the option within rclone which should
 map to the external options very easily with a few exceptions.
 
+### options/info: Get info about all the global options {#options-info}
+
+Returns an object where keys are option block names and values are an
+array of objects with info about each options.
+
+These objects are in the same format as returned by "config/providers". They are
+described in the [option blocks](#option-blocks) section.
+
 ### options/local: Get the currently active config for this call {#options-local}
 
 Returns an object with the keys "config" and "filter".

fs/config/rc.go

@@ -91,7 +91,12 @@ func init() {
 Returns a JSON object:
 - providers - array of objects
 
-See the [config providers](/commands/rclone_config_providers/) command for more information on the above.
+See the [config providers](/commands/rclone_config_providers/) command
+for more information on the above.
+
+Note that the Options blocks are in the same format as returned by
+"options/info". They are described in the
+[option blocks](#option-blocks) section.
 `,
 	})
 }

fs/fs_test.go

@@ -234,10 +234,8 @@ func TestOptionMarshalJSON(t *testing.T) {
 "Name": "case_insensitive",
 "FieldName": "",
 "Help": "",
-"Provider": "",
 "Default": false,
 "Value": true,
-"ShortOpt": "",
 "Hide": 0,
 "Required": false,
 "IsPassword": false,

fs/rc/config.go

@@ -12,19 +12,6 @@ import (
 	"github.com/rclone/rclone/fs/filter"
 )
 
-// AddOption adds an option set
-func AddOption(name string, option interface{}) {
-	// FIXME remove this function when conversion to options is complete
-	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: name, Opt: option})
-}
-
-// AddOptionReload adds an option set with a reload function to be
-// called when options are changed
-func AddOptionReload(name string, option interface{}, reload func(context.Context) error) {
-	// FIXME remove this function when conversion to options is complete
-	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: name, Opt: option, Reload: reload})
-}
-
 func init() {
 	Add(Call{
 		Path:  "options/blocks",
@@ -73,6 +60,29 @@ func rcOptionsGet(ctx context.Context, in Params) (out Params, err error) {
 	return out, nil
 }
 
+func init() {
+	Add(Call{
+		Path:  "options/info",
+		Fn:    rcOptionsInfo,
+		Title: "Get info about all the global options",
+		Help: `Returns an object where keys are option block names and values are an
+array of objects with info about each options.
+
+These objects are in the same format as returned by "config/providers". They are
+described in the [option blocks](#option-blocks) section.
+`,
+	})
+}
+
+// Show the info of all the option blocks
+func rcOptionsInfo(ctx context.Context, in Params) (out Params, err error) {
+	out = make(Params)
+	for _, opt := range fs.OptionsRegistry {
+		out[opt.Name] = opt.Options
+	}
+	return out, nil
+}
+
 func init() {
 	Add(Call{
 		Path:  "options/local",

fs/rc/config_test.go

@@ -20,6 +20,16 @@ func clearOptionBlock() func() {
 	}
 }
 
+var testInfo = fs.Options{{
+	Name:    "string",
+	Default: "str",
+	Help:    "It is a string",
+}, {
+	Name:    "int",
+	Default: 17,
+	Help:    "It is an int",
+}}
+
 var testOptions = struct {
 	String string
 	Int    int
@@ -28,10 +38,18 @@ var testOptions = struct {
 	Int:    42,
 }
 
+func registerTestOptions() {
+	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: "potato", Opt: &testOptions, Options: testInfo})
+}
+
+func registerTestOptionsReload(reload func(context.Context) error) {
+	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: "potato", Opt: &testOptions, Options: testInfo, Reload: reload})
+}
+
 func TestAddOption(t *testing.T) {
 	defer clearOptionBlock()()
 	assert.Equal(t, len(fs.OptionsRegistry), 0)
-	AddOption("potato", &testOptions)
+	registerTestOptions()
 	assert.Equal(t, len(fs.OptionsRegistry), 1)
 	assert.Equal(t, &testOptions, fs.OptionsRegistry["potato"].Opt)
 }
@@ -40,7 +58,7 @@ func TestAddOptionReload(t *testing.T) {
 	defer clearOptionBlock()()
 	assert.Equal(t, len(fs.OptionsRegistry), 0)
 	reload := func(ctx context.Context) error { return nil }
-	AddOptionReload("potato", &testOptions, reload)
+	registerTestOptionsReload(reload)
 	assert.Equal(t, len(fs.OptionsRegistry), 1)
 	assert.Equal(t, &testOptions, fs.OptionsRegistry["potato"].Opt)
 	assert.Equal(t, fmt.Sprintf("%p", reload), fmt.Sprintf("%p", fs.OptionsRegistry["potato"].Reload))
@@ -48,7 +66,7 @@ func TestAddOptionReload(t *testing.T) {
 
 func TestOptionsBlocks(t *testing.T) {
 	defer clearOptionBlock()()
-	AddOption("potato", &testOptions)
+	registerTestOptions()
 	call := Calls.Get("options/blocks")
 	require.NotNil(t, call)
 	in := Params{}
@@ -60,7 +78,7 @@ func TestOptionsBlocks(t *testing.T) {
 
 func TestOptionsGet(t *testing.T) {
 	defer clearOptionBlock()()
-	AddOption("potato", &testOptions)
+	registerTestOptions()
 	call := Calls.Get("options/get")
 	require.NotNil(t, call)
 	in := Params{}
@@ -76,8 +94,8 @@ func TestOptionsGetMarshal(t *testing.T) {
 	ci := fs.GetConfig(ctx)
 
 	// Add some real options
-	AddOption("main", ci)
+	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: "main", Opt: ci, Options: nil})
-	AddOption("rc", &Opt)
+	fs.RegisterGlobalOptions(fs.OptionsInfo{Name: "rc", Opt: &Opt, Options: nil})
 
 	// get them
 	call := Calls.Get("options/get")
@@ -92,11 +110,23 @@ func TestOptionsGetMarshal(t *testing.T) {
 	require.NoError(t, err)
 }
 
+func TestOptionsInfo(t *testing.T) {
+	defer clearOptionBlock()()
+	registerTestOptions()
+	call := Calls.Get("options/info")
+	require.NotNil(t, call)
+	in := Params{}
+	out, err := call.Fn(context.Background(), in)
+	require.NoError(t, err)
+	require.NotNil(t, out)
+	assert.Equal(t, Params{"potato": testInfo}, out)
+}
+
 func TestOptionsSet(t *testing.T) {
 	defer clearOptionBlock()()
 	var reloaded int
-	AddOptionReload("potato", &testOptions, func(ctx context.Context) error {
+	registerTestOptionsReload(func(ctx context.Context) error {
-		if reloaded > 0 {
+		if reloaded > 1 {
 			return errors.New("error while reloading")
 		}
 		reloaded++
@@ -114,8 +144,8 @@ func TestOptionsSet(t *testing.T) {
 	require.NoError(t, err)
 	require.Nil(t, out)
 	assert.Equal(t, 50, testOptions.Int)
-	assert.Equal(t, "hello", testOptions.String)
+	assert.Equal(t, "str", testOptions.String)
-	assert.Equal(t, 1, reloaded)
+	assert.Equal(t, 2, reloaded)
 
 	// error from reload
 	_, err = call.Fn(context.Background(), in)

fs/registry.go

@@ -195,11 +195,11 @@ type Option struct {
 	FieldName  string           // name of the field used in the rc JSON - will be auto filled normally
 	Help       string           // help, start with a single sentence on a single line that will be extracted for command line help
 	Groups     string           `json:",omitempty"` // groups this option belongs to - comma separated string for options classification
-	Provider   string           // set to filter on provider
+	Provider   string           `json:",omitempty"` // set to filter on provider
 	Default    interface{}      // default value, nil => "", if set (and not to nil or "") then Required does nothing
 	Value      interface{}      // value to be set by flags
 	Examples   OptionExamples   `json:",omitempty"` // predefined values that can be selected from list (multiple-choice option)
-	ShortOpt   string           // the short option for this if required
+	ShortOpt   string           `json:",omitempty"` // the short option for this if required
 	Hide       OptionVisibility // set this to hide the config from the configurator or the command line
 	Required   bool             // this option is required, meaning value cannot be empty unless there is a default
 	IsPassword bool             // set if the option is a password
@@ -348,7 +348,7 @@ func (os OptionExamples) Sort() { sort.Sort(os) }
 type OptionExample struct {
 	Value    string
 	Help     string
-	Provider string
+	Provider string `json:",omitempty"`
 }
 
 // Register a filesystem
@@ -417,6 +417,7 @@ var OptionsRegistry = map[string]OptionsInfo{}
 //
 // Packages which need global options should use this in an init() function
 func RegisterGlobalOptions(oi OptionsInfo) {
+	oi.Options.setValues()
 	OptionsRegistry[oi.Name] = oi
 	if oi.Opt != nil && oi.Options != nil {
 		err := oi.Check()
@@ -429,7 +430,10 @@ func RegisterGlobalOptions(oi OptionsInfo) {
 var optionName = regexp.MustCompile(`^[a-z0-9_]+$`)
 
 // Check ensures that for every element of oi.Options there is a field
-// in oi.Opt that matches it
+// in oi.Opt that matches it.
+//
+// It also sets Option.FieldName to be the name of the field for use
+// in JSON.
 func (oi *OptionsInfo) Check() error {
 	errCount := errcount.New()
 	items, err := configstruct.Items(oi.Opt)
@@ -471,6 +475,8 @@ func (oi *OptionsInfo) Check() error {
 			//errCount.Add(err)
 			Errorf(nil, "%s", err)
 		}
+		// Set FieldName
+		option.FieldName = item.Field
 	}
 	return errCount.Err(fmt.Sprintf("internal error: options block %q", oi.Name))
 }