cmd/cue/cmd: introduce help topics for new CLI
Closes #280
Issue #190
Issue #130
Issue #116
Issue #91
Change-Id: I1d5cf2018cdd8be2625313e302cee4087b48f6f7
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/5160
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
diff --git a/cmd/cue/cmd/cmd.go b/cmd/cue/cmd/cmd.go
index 8318f54..05756cb 100644
--- a/cmd/cue/cmd/cmd.go
+++ b/cmd/cue/cmd/cmd.go
@@ -25,7 +25,7 @@
func newCmdCmd(c *Command) *cobra.Command {
cmd := &cobra.Command{
- Use: "cmd <name> [-x] [instances]",
+ Use: "cmd <name> [inputs]",
Short: "run a user-defined shell command",
Long: `cmd executes defined the named command for each of the named instances.
@@ -52,7 +52,7 @@
command: [Name=string]: { // from tool.Command
// usage gives a short usage pattern of the command.
// Example:
- // fmt [-n] [-x] [packages]
+ // fmt [-s] [inputs]
usage?: Name | string
// short gives a brief on-line description of the command.
diff --git a/cmd/cue/cmd/flags.go b/cmd/cue/cmd/flags.go
index 8d721a1..07941ee 100644
--- a/cmd/cue/cmd/flags.go
+++ b/cmd/cue/cmd/flags.go
@@ -65,9 +65,10 @@
func addOrphanFlags(f *pflag.FlagSet) {
f.StringP(string(flagPackage), "p", "", "package name for non-CUE files")
+ f.StringP(string(flagSchema), "d", "",
+ "expression to select schema for evaluating values in non-CUE files")
f.StringArrayP(string(flagPath), "l", nil, "CUE expression for single path component")
f.Bool(string(flagList), false, "concatenate multiple objects into a list")
- f.Bool(string(flagFiles), false, "split multiple entries into different files")
f.Bool(string(flagWithContext), false, "import as object with contextual data")
f.StringArrayP(string(flagProtoPath), "I", nil, "paths in which to search for imports")
f.StringP(string(flagGlob), "n", "", "glob filter for file names")
diff --git a/cmd/cue/cmd/fmt.go b/cmd/cue/cmd/fmt.go
index 2481e4a..b9c9b2a 100644
--- a/cmd/cue/cmd/fmt.go
+++ b/cmd/cue/cmd/fmt.go
@@ -26,7 +26,7 @@
func newFmtCmd(c *Command) *cobra.Command {
cmd := &cobra.Command{
- Use: "fmt [-s] [packages]",
+ Use: "fmt [-s] [inputs]",
Short: "formats CUE configuration files",
Long: `Fmt formats the given files or the files for the given packages in place
`,
diff --git a/cmd/cue/cmd/help.go b/cmd/cue/cmd/help.go
new file mode 100644
index 0000000..49584be
--- /dev/null
+++ b/cmd/cue/cmd/help.go
@@ -0,0 +1,269 @@
+// Copyright 2020 CUE Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+ "github.com/spf13/cobra"
+)
+
+// TODO: intersperse the examples at the end of the texts in the
+// body of text to make things more concerte for the user early on?
+// The current approach works will if users just print the text without
+// "more" or "less", in which case the examples show more prominently.
+// The user can then scroll up to get a more in-depth explanation. But is
+// this how users use it?
+
+func newHelpTopics(c *Command) []*cobra.Command {
+ return []*cobra.Command{
+ inputsHelp,
+ flagsHelp,
+ filetypeHelp,
+ }
+}
+
+var inputsHelp = &cobra.Command{
+ Use: "inputs",
+ Short: "package list, patterns, and files",
+ Long: `Many commands apply to a set of inputs:
+
+cue <command> [inputs]
+
+The list [inputs] may specify CUE packages, CUE files, non-CUE
+files or some combinations of those. An empty list specifies
+the package in the current directory, provided there is a single
+named package in this directory.
+
+CUE packages are specified as an import path. An import path
+that is a rooted path --one that begins with a "." or ".."
+element-- is interpreted as a file system path and denotes the
+package instance in that directory.
+
+Otherwise, the import path P denotes and external package found
+in cue.mod/{pkg|gen|usr}/P.
+
+An import path may contain one or more "..." to match any
+subdirectory: pkg/... matches all packages below pkg, including
+pkg itself, while foo/.../bar matches all directories named bar
+within foo. In all cases, directories containing cue.mod
+directories are excluded from the result.
+
+A package may also be specified as a list of .cue files.
+The special symbol '-' denotes stdin or stdout and defaults to
+the cue file type for stdin. For stdout, the default depends on
+the cue command. A .cue file package may not be combined with
+regular packages.
+
+Non-cue files are interpreted based on their file extension or,
+if present, an explicit file qualifier (see the "filetypes"
+help topic). Non-cue files may be interpreted as concrete data
+or schema. Schema are treated as single-file packages by default.
+See the "filetypes" and "flags" help topics on how to combine
+schema into a single package.
+
+Data files can be combined into a single package, in which case
+each file is unified into a defined location within this single
+package. If a data file has multiple values, such as allowed
+with JSON Lines or YAML, each value is interpreted as a separate
+file.
+
+The --schema/-d flag can be used to unify each data file against
+a specific schema within a non-data package. For OpenAPI, the -d
+flag specifies a schema name. For JSON Schema the -d flag
+specifies a schema defined in "definitions". In all other cases,
+the -d flag is a CUE expression that is evaluated within the
+package.
+
+Examples (also see also "flags" and "filetypes" help topics):
+
+# Show the definition of each package named foo for each
+# directory dir under path.
+$ cue def ./path/.../dir:foo
+
+# Unify each document in foo.yaml with the value Foo in pkg.
+$ cue export ./pkg -d Foo foo.yaml
+
+# Unify data.json with schema.json.
+$ cue export data.json schema: schema.json
+`,
+}
+
+var flagsHelp = &cobra.Command{
+ Use: "flags",
+ Short: "common flags for composing packages",
+ Long: `Non-CUE files are treated as individual files by
+default, but can be combined into a single package using a
+combination of the following flags.
+
+
+Assigning values to a CUE path
+
+The --path/-l flag can be used to specify a CUE path at which to
+place a value. Each -l flag specifies either a CUE expression or
+a CUE field (without the value following the colon), both of
+which are evaluated within the value. Together, the -l flags
+specify the path at increasingly deeper nesting. In the path
+notation, path elements that end with a "::", instead of ":",
+are created as definitions. An expression may refer to builtin
+packages as long as the name can be uniquely identified.
+
+The --with-context flag can be used to evaluate the label
+expression within a struct of contextual data, instead of
+within the value itself. This struct has the following fields:
+
+{
+ // data holds the original source data
+ // (perhaps one of several records in a file).
+ data: _
+ // filename holds the full path to the file.
+ filename: string
+ // index holds the 0-based index element of the
+ // record within the file. For files containing only
+ // one record, this will be 0.
+ index: uint & <recordCount
+ // recordCount holds the total number of records
+ // within the file.
+ recordCount: int & >=1
+}
+
+
+Handling multiple documents or streams
+
+To handle multi-document files, such as JSON Lines or YAML
+files with document separators (---), the user must specify
+a the --path, --list, or --files flag.
+The --path flag merges each element into a single package as
+if each element was defined in a separate file. The --list flag
+concatenates each entry in a file into a list.
+Using --list flag in combination with the --path flag
+concatenates entries with the same path into a list, instead of
+unifying them.
+Finally, the --files option causes each entry to be written to
+a different file. The -files flag may only be used in
+combination with the import command.
+
+
+Examples:
+
+# Put a value at a path based on its "kind" and "name" fields.
+$ cue eval -l 'strings.ToLower(kind)' -l name foo.yaml
+
+# Include a schema under the "myschema" field using the path notation.
+$ cue eval -l myschema: schema: foo.json
+
+# Base the path values on its kind and file name.
+$ cue eval --with-context -l 'path.Base(filename)' -l data.kind foo.yaml
+`,
+}
+
+var filetypeHelp = &cobra.Command{
+ Use: "filetypes",
+ Short: "supported file types and qualifiers",
+ Long: `The cue tools supports the following file types:
+
+ Tag Extensions Description
+ cue .cue CUE source files.
+ json .json JSON files.
+ yaml .yaml/.yml YAML files.
+ jsonl .jsonl/.ldjson Line-separated JSON values.
+ jsonschema JSON Schema.
+ openapi OpenAPI schema.
+ proto .proto Protocol Buffer definitions.
+ go .go Go source files.
+ text .txt Raw text file; the evaluated
+ value must be of type string.
+
+OpenAPI, JSON Schema and Protocol Buffer definitions are
+always interpreted as schema. YAML and JSON are always
+interpreted as data. CUE and Go are interpreted as schema by
+default, but may be selected to operate in data mode.
+
+The cue tool will infer a file's type from its extension by
+default. The user my override this behavior by using qualifiers.
+A qualifier takes the form
+
+ <tag>{'+'<tag>}':'
+
+For instance,
+
+ cue eval json: foo.data
+
+specifies that 'foo.data' should be read as a JSON file. File
+formats that do not have a default extension may be represented
+in any data format using the same notation:
+
+ cue def jsonschema: bar.cue foo.yaml openapi+yaml: baz.def
+
+interprets the files bar.cue and foo.yaml as data in the
+respective formats encoding an JSON Schema, while 'baz.def' is
+defined to be a YAML file which contents encode OpenAPI
+definitions.
+
+A qualifier applies to all files following it on the command line
+until the next qualifier. The cue tool does not allow a ':' in
+filenames.
+
+The following tags can be used in qualifiers to further
+influence input or output. For input these act as
+restrictions, validating the input. For output these act
+as filters, showing only the requested data and picking
+defaults as requested.
+
+ Tag Description
+ data Require concrete input and output that does
+ not require any evaluation.
+ graph Like data, but allow references.
+ schema Export data and definitions.
+
+Many commands also support the --out and --outfile/-o flags.
+The --out flag specifies the output type using a qualifier
+(without the ':'). The -o flag specifies an output file
+possibly prefixed with a qualifier.
+
+Examples:
+
+# Interpret bar.cue and foo.yaml as OpenAPI data.
+$ cue def openapi: bar.cue foo.yaml
+
+# Write a CUE package as OpenAPI encoded as YAML, using
+# an alternate file extension.
+$ cue def -o openapi+yaml:foo.openapi
+
+# Print the data for the current package as YAML.
+$ cue export --out=yaml
+
+# Print the string value of the "name" field as a string.
+$ cue export -e name --out=text
+
+# Write the string value of the "name" field to a text file.
+$ cue export -e name -o=foo.txt
+
+# Write the string value of the "name" field to a file foo.
+$ cue export -e name -o=text:foo
+`,
+}
+
+// TODO: tags
+// - doc/nodoc
+// - attr/noattr
+// - id=<url>
+
+// TODO: filetypes:
+// - textpb
+// - binpb
+
+// TODO: document
+// <tag>['='<value>]{'+'<tag>['='<value>]}':'
+
+// TODO: cue.mod help topic
diff --git a/cmd/cue/cmd/import.go b/cmd/cue/cmd/import.go
index 52ca926..ec4a48f 100644
--- a/cmd/cue/cmd/import.go
+++ b/cmd/cue/cmd/import.go
@@ -47,9 +47,10 @@
YAML .yaml .yml
protobuf .proto
-Files can either be specified explicitly, or inferred from the specified
-packages. In either case, the file extension is replaced with .cue. It will
-fail if the file already exists by default. The -f flag overrides this.
+Files can either be specified explicitly, or inferred from the
+specified packages. In either case, the file extension is
+replaced with .cue. It will fail if the file already exists by
+default. The -f flag overrides this.
Examples:
@@ -59,44 +60,8 @@
# Convert all json files in the indicated directories:
$ cue import ./... -type=json
-
-The --path flag
-
-By default the parsed files are included as emit values. This default can be
-overridden by specifying a sequence of labels as you would in a CUE file.
-An identifier or string label are interpreted as usual. A label expression is
-evaluated within the context of the imported file. label expressions may also
-refer to builtin packages, which will be implicitly imported.
-
-The --with-context flag can be used to evaluate the label expression within
-a struct with the following fields:
-
-{
- // data holds the original source data
- // (perhaps one of several records in a file).
- data: _
- // filename holds the full path to the file.
- filename: string
- // index holds the 0-based index element of the
- // record within the file. For files containing only
- // one record, this will be 0.
- index: uint & <recordCount
- // recordCount holds the total number of records
- // within the file.
- recordCount: int & >=1
-}
-
-Handling multiple documents or streams
-
-To handle Multi-document files, such as concatenated JSON objects or
-YAML files with document separators (---) the user must specify either the
---path, --list, or --files flag. The -path flag assign each element to a path
-(identical paths are treated as usual); -list concatenates the entries, and
---files causes each entry to be written to a different file. The -files flag
-may only be used if files are explicitly imported. The --list flag may be
-used in combination with the -path flag, concatenating each entry to the
-mapped location.
-
+The "flags" help topic describes how to assign values to a
+specific path within a CUE namespace. Some examples of that
Examples:
@@ -214,14 +179,13 @@
}
addOutFlags(cmd.Flags(), false)
-
addOrphanFlags(cmd.Flags())
+ cmd.Flags().Bool(string(flagFiles), false, "split multiple entries into different files")
cmd.Flags().String(string(flagType), "", "only apply to files of this type")
cmd.Flags().BoolP(string(flagForce), "f", false, "force overwriting existing files")
cmd.Flags().Bool(string(flagDryrun), false, "only run simulation")
cmd.Flags().BoolP(string(flagRecursive), "R", false, "recursively parse string values")
- cmd.Flags().String("fix", "", "apply given fix") // XXX
return cmd
}
diff --git a/cmd/cue/cmd/root.go b/cmd/cue/cmd/root.go
index b9396ae..7a66c33 100644
--- a/cmd/cue/cmd/root.go
+++ b/cmd/cue/cmd/root.go
@@ -103,6 +103,7 @@
// Hidden
newAddCmd(c),
}
+ subCommands = append(subCommands, newHelpTopics(c)...)
addGlobalFlags(cmd.PersistentFlags())
diff --git a/cmd/cue/cmd/testdata/script/help_cmd.txt b/cmd/cue/cmd/testdata/script/help_cmd.txt
index c900461..e4f6113 100644
--- a/cmd/cue/cmd/testdata/script/help_cmd.txt
+++ b/cmd/cue/cmd/testdata/script/help_cmd.txt
@@ -49,7 +49,7 @@
command: [Name=string]: { // from tool.Command
// usage gives a short usage pattern of the command.
// Example:
- // fmt [-n] [-x] [packages]
+ // fmt [-s] [inputs]
usage?: Name | string
// short gives a brief on-line description of the command.
@@ -213,7 +213,7 @@
}
Usage:
- cue cmd <name> [-x] [instances] [flags]
+ cue cmd <name> [inputs] [flags]
cue cmd [command]
Available Commands:
diff --git a/cmd/cue/cmd/testdata/script/help_doc.txt b/cmd/cue/cmd/testdata/script/help_doc.txt
new file mode 100644
index 0000000..fdb55b5
--- /dev/null
+++ b/cmd/cue/cmd/testdata/script/help_doc.txt
@@ -0,0 +1,43 @@
+# Print the data for the current package a yaml.
+cue export --out=yaml
+cmp stdout stdout-export
+
+# Print the string value of the name field as a string.
+cue export -e name --out=text
+cmp stdout expect-stdout
+
+# Write the string value of the name field to a txt file.
+cue export -e name -o=foo.txt
+cmp stdout-foo foo.txt
+
+# Write the string value of the name field to a file foo.
+cue export -e name -o=text:foo
+cmp stdout-foo foo
+
+# Interpret bar.cue and foo.yaml as OpenAPI data.
+# cue def openapi: bar.cue foo.yaml
+
+# Write a CUE package as openapi encoded as YAML, using
+# an alternate file extension.
+# cue def -o openapi+yaml:foo.openapi
+
+-- foo.cue --
+package bar
+
+name: "foo"
+D :: int
+
+-- bar.cue --
+3
+
+-- foo.yaml --
+3
+
+-- stdout-export --
+name: foo
+-- stdout-foo --
+foo
+-- stdout-name --
+"foo"
+-- expect-stdout --
+foo
diff --git a/cmd/cue/cmd/vet.go b/cmd/cue/cmd/vet.go
index 8d80a50..12ea5a4 100644
--- a/cmd/cue/cmd/vet.go
+++ b/cmd/cue/cmd/vet.go
@@ -74,9 +74,6 @@
cmd.Flags().BoolP(string(flagConcrete), "c", false,
"require the evaluation to be concrete")
- cmd.Flags().StringP(string(flagSchema), "d", "",
- "expression to select schema for evaluating values in non-CUE files")
-
cmd.Flags().StringArrayP(string(flagTags), "t", nil,
"set the value of a tagged field")
diff --git a/internal/encoding/encoder.go b/internal/encoding/encoder.go
index 5f7c8f2..34d8f24 100644
--- a/internal/encoding/encoder.go
+++ b/internal/encoding/encoder.go
@@ -164,11 +164,15 @@
case build.Text:
e.encValue = func(v cue.Value) error {
- str, err := v.String()
+ s, err := v.String()
if err != nil {
return err
}
- _, err = fmt.Fprint(w, str)
+ _, err = fmt.Fprint(w, s)
+ if err != nil {
+ return err
+ }
+ _, err = fmt.Fprintln(w)
return err
}
