checkpoint: began to create schema and code generator

cmd/enbas-cli-generators/main.go

@@ -0,0 +1,91 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"text/template"
+	"unicode"
+)
+
+func main() {
+	var (
+		enbasCLISchemaFilepath string
+		executorsFilePath      string
+	)
+
+	flag.StringVar(&enbasCLISchemaFilepath, "path-to-enbas-cli-schema", "", "The path to the Enbas CLI schema file")
+	flag.StringVar(&executorsFilePath, "path-to-enbas-executors", "", "The path to the executors Go file")
+	flag.Parse()
+
+	schema, err := readSchemaFile(enbasCLISchemaFilepath)
+	if err != nil {
+		fmt.Printf("ERROR: Unable to read the schema file: %v.\n", err)
+	}
+
+	if err := generateExecutors(schema, executorsFilePath); err != nil {
+		fmt.Printf("ERROR: Unable to generate the executors: %v.\n", err)
+	}
+
+	if err := runGoImports(executorsFilePath); err != nil {
+		fmt.Printf("ERROR: Unable to run goimports: %v.\n", err)
+	}
+}
+
+func readSchemaFile(path string) (enbasCLISchema, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return enbasCLISchema{}, fmt.Errorf("unable to open the schema file: %w", err)
+	}
+	defer file.Close()
+
+	var schema enbasCLISchema
+
+	if err := json.NewDecoder(file).Decode(&schema); err != nil {
+		return enbasCLISchema{}, fmt.Errorf("unable to decode the JSON data: %w", err)
+	}
+
+	return schema, nil
+}
+
+func generateExecutors(schema enbasCLISchema, output string) error {
+	funcMap := template.FuncMap{
+		"capitalise":         capitalise,
+		"getFlagType":        schema.Flags.getType,
+		"getFlagDescription": schema.Flags.getDescription,
+	}
+
+	tmpl := template.Must(template.New("executor-template").Funcs(funcMap).Parse(executorsFileTemplate))
+
+	file, err := os.Create(output)
+	if err != nil {
+		return fmt.Errorf("unable to create the output file: %w", err)
+	}
+	defer file.Close()
+
+	if err := tmpl.Execute(file, schema.Commands); err != nil {
+		return fmt.Errorf("unable to generate the code from the template: %w", err)
+	}
+
+	return nil
+}
+
+func runGoImports(path string) error {
+	imports := exec.Command("goimports", "-w", path)
+
+	if err := imports.Run(); err != nil {
+		return fmt.Errorf("received an error after running goimports: %w", err)
+	}
+
+	return nil
+}
+
+func capitalise(str string) string {
+	runes := []rune(str)
+
+	runes[0] = unicode.ToUpper(runes[0])
+
+	return string(runes)
+}

cmd/enbas-cli-generators/schema.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+type enbasCLISchema struct {
+	Flags    enbasCLISchemaFlagMap            `json:"flags"`
+	Commands map[string]enbasCLISchemaCommand `json:"commands"`
+}
+
+func newEnbasCLISchemaFromFile(path string) (enbasCLISchema, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return enbasCLISchema{}, fmt.Errorf("unable to open the schema file: %w", err)
+	}
+	defer file.Close()
+
+	var schema enbasCLISchema
+
+	if err := json.NewDecoder(file).Decode(&schema); err != nil {
+		return enbasCLISchema{}, fmt.Errorf("unable to decode the JSON data: %w", err)
+	}
+
+	return schema, nil
+}
+
+type enbasCLISchemaFlag struct {
+	Type        string `json:"type"`
+	Description string `json:"description"`
+}
+
+type enbasCLISchemaFlagMap map[string]enbasCLISchemaFlag
+
+func (e enbasCLISchemaFlagMap) getType(name string) string {
+	flag, ok := e[name]
+	if !ok {
+		return "UNKNOWN TYPE"
+	}
+
+	return flag.Type
+}
+
+func (e enbasCLISchemaFlagMap) getDescription(name string) string {
+	flag, ok := e[name]
+	if !ok {
+		return "UNKNOWN DESCRIPTION"
+	}
+
+	return flag.Description
+}
+
+type enbasCLISchemaCommand struct {
+	AddPrinter bool                          `json:"addPrinter"`
+	AddConfig  bool                          `json:"addConfig"`
+	Flags      []enbasCLISchemaFlagReference `json:"flags"`
+	Summary    string                        `json:"summary"`
+}
+
+type enbasCLISchemaFlagReference struct {
+	Flag    string `json:"flag"`
+	Default string `json:"default"`
+}

cmd/enbas-cli-generators/templates.go

@@ -0,0 +1,36 @@
+package main
+
+var executorsFileTemplate = `package executor
+{{ range $name, $command := . }}
+{{- $struct_name := capitalise $name | printf "%sExecutor" -}}
+{{- $new_executor_function_name := capitalise $name | printf "New%sExecutor" -}}
+{{ print "" }}
+// {{ $struct_name }} is the executor for the {{ $name }} command.
+type {{ $struct_name }} struct {
+	*flag.FlagSet
+	{{- range $flag := $command.Flags -}}
+	{{ print "" }}
+	{{ $flag.Flag }} {{ getFlagType $flag.Flag }}
+	{{- end -}}
+	{{ print "" }}
+}
+
+func {{ $new_executor_function_name }}() *{{ $struct_name }} {
+	exe := {{ $struct_name }}{
+		FlagSet: flag.NewFlagSet({{ printf "%q" $name }}, flag.ExitOnError),
+	}
+	{{ print "" }}
+	exe.Usage = commandUsageFunc({{ printf "%q" $name }}, {{ printf "%q" $command.Summary }}, showExe.FlagSet)
+	{{ print "" }}
+	{{- range $flag := $command.Flags -}}
+	{{- if eq (getFlagType $flag.Flag) "string" -}}
+	exe.StringVar(&exe.{{ $flag.Flag }}, {{ printf "%q" $flag.Flag }}, {{ printf "%q" $flag.Default }}, {{ getFlagDescription $flag.Flag | printf "%q" }})
+	{{- else if eq (getFlagType $flag.Flag) "bool" -}}
+	exe.BoolVar(&exe.{{ $flag.Flag }}, {{ printf "%q" $flag.Flag }}, {{ $flag.Default }}, {{ getFlagDescription $flag.Flag | printf "%q" }})
+	{{- end -}}
+	{{- end -}}
+	{{ print "" }}
+	return &exe
+}
+{{ end }}
+`

internal/internal.go

@@ -1,5 +1,7 @@
 package internal
 
+//go:generate go run ../cmd/enbas-cli-generators --path-to-enbas-cli-schema ../schema/enbas_cli_schema.json --path-to-enbas-executors ../executors-wip.go
+
 const (
 	ApplicationName    = "enbas"
 	ApplicationWebsite = "https://codeflow.dananglin.me.uk/apollo/enbas"

schema/enbas_cli_schema.json

@@ -0,0 +1,31 @@
+{
+  "flags": {
+    "full": {
+      "type": "bool",
+      "description": "Set to true to print the build information in full"
+    },
+    "instance": {
+      "type": "string",
+      "description": "The instance that you want to log into"
+    }
+  },
+
+  "commands": {
+    "login": {
+      "addPrinter": true,
+      "addConfig": true,
+      "flags": [
+        { "flag": "instance", "default": "" }
+      ],
+      "summary": "Login to an account on GoToSocial"
+    },
+    "version": {
+      "addPrinter": true,
+      "addConfig": false,
+      "summary": "Prints the application's version and build information",
+      "flags": [
+        { "flag": "full", "default": "false" }
+      ]
+    }
+  }
+}