go-jsonnet/jsonnet/cmd.go
Stanisław Barzowski 2db3d1c3cc TLA support
2017-10-12 20:00:45 -04:00

119 lines
2.6 KiB
Go

/*
Copyright 2017 Google Inc. All rights reserved.
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 main
import (
"fmt"
"io/ioutil"
"log"
"os"
"runtime/pprof"
"strings"
"github.com/google/go-jsonnet"
)
func usage() {
fmt.Println("usage: jsonnet <filename>")
}
func getVar(s string) (string, string, error) {
parts := strings.SplitN(s, "=", 2)
name := parts[0]
if len(parts) == 1 {
content, exists := os.LookupEnv(name)
if exists {
return name, content, nil
}
return "", "", fmt.Errorf("ERROR: Environment variable %v was undefined.", name)
} else {
return name, parts[1], nil
}
}
func main() {
// https://blog.golang.org/profiling-go-programs
var cpuprofile = os.Getenv("JSONNET_CPU_PROFILE")
if cpuprofile != "" {
f, err := os.Create(cpuprofile)
if err != nil {
log.Fatal(err)
}
pprof.StartCPUProfile(f)
defer pprof.StopCPUProfile()
}
// TODO(sbarzowski) Be consistent about error codes with C++ maybe
var filename string
vm := jsonnet.MakeVM()
for i := 1; i < len(os.Args); i++ {
arg := os.Args[i]
switch arg {
case "--tla-str":
i++
name, content, err := getVar(os.Args[i])
if err != nil {
fmt.Fprintln(os.Stderr, err.Error())
os.Exit(1)
}
vm.TLAVar(name, content)
case "--tla-code":
i++
name, content, err := getVar(os.Args[i])
if err != nil {
fmt.Fprintln(os.Stderr, err.Error())
os.Exit(1)
}
vm.TLACode(name, content)
case "--ext-code":
i++
name, content, err := getVar(os.Args[i])
if err != nil {
fmt.Fprintln(os.Stderr, err.Error())
os.Exit(1)
}
vm.ExtCode(name, content)
case "--ext-str":
i++
name, content, err := getVar(os.Args[i])
if err != nil {
fmt.Fprintln(os.Stderr, err.Error())
os.Exit(1)
}
vm.ExtVar(name, content)
default:
if filename != "" {
usage()
os.Exit(1)
}
filename = arg
}
}
snippet, err := ioutil.ReadFile(filename)
if err != nil {
fmt.Fprintf(os.Stderr, "Error reading input file: %v\n", err.Error())
os.Exit(1)
}
json, err := vm.EvaluateSnippet(filename, string(snippet))
if err != nil {
fmt.Fprintf(os.Stderr, "%v\n", err.Error())
os.Exit(2)
}
fmt.Println(json)
}