open-nomad/jobspec2/parse.go
2020-11-09 16:27:22 -05:00

169 lines
3.1 KiB
Go

package jobspec2
import (
"bytes"
"errors"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"strings"
"github.com/hashicorp/hcl/v2"
"github.com/hashicorp/hcl/v2/ext/dynblock"
"github.com/hashicorp/hcl/v2/hclsyntax"
hcljson "github.com/hashicorp/hcl/v2/json"
"github.com/hashicorp/nomad/api"
"github.com/hashicorp/nomad/jobspec2/hclutil"
)
func Parse(path string, r io.Reader) (*api.Job, error) {
if path == "" {
if f, ok := r.(*os.File); ok {
path = f.Name()
}
}
var buf bytes.Buffer
_, err := io.Copy(&buf, r)
if err != nil {
return nil, err
}
return ParseWithConfig(&ParseConfig{
Path: path,
Body: buf.Bytes(),
AllowFS: false,
Strict: true,
})
}
func ParseWithConfig(args *ParseConfig) (*api.Job, error) {
args.normalize()
c := newJobConfig(args)
err := decode(c)
if err != nil {
return nil, err
}
normalizeJob(c)
return c.Job, nil
}
type ParseConfig struct {
Path string
BaseDir string
// Body is the HCL body
Body []byte
// AllowFS enables HCL functions that require file system accecss
AllowFS bool
// ArgVars is the CLI -var arguments
ArgVars []string
// VarFiles is the paths of variable data files
VarFiles []string
// Envs represent process environment variable
Envs []string
Strict bool
// parsedVarFiles represent parsed HCL AST of the passed EnvVars
parsedVarFiles []*hcl.File
}
func (c *ParseConfig) normalize() {
if c.BaseDir == "" {
c.BaseDir = filepath.Dir(c.Path)
}
}
func decode(c *jobConfig) error {
var file *hcl.File
var diags hcl.Diagnostics
pc := c.ParseConfig
if !isJSON(pc.Body) {
file, diags = hclsyntax.ParseConfig(pc.Body, pc.Path, hcl.Pos{Line: 1, Column: 1})
} else {
file, diags = hcljson.Parse(pc.Body, pc.Path)
}
parsedVarFiles, mdiags := parseVarFiles(pc.VarFiles)
pc.parsedVarFiles = parsedVarFiles
diags = append(diags, mdiags...)
if diags.HasErrors() {
return diags
}
body := hclutil.BlocksAsAttrs(file.Body)
body = dynblock.Expand(body, c.EvalContext())
diags = c.decodeBody(body)
if diags.HasErrors() {
var str strings.Builder
for i, diag := range diags {
if i != 0 {
str.WriteByte('\n')
}
str.WriteString(diag.Error())
}
return errors.New(str.String())
}
diags = append(diags, decodeMapInterfaceType(&c, c.EvalContext())...)
return nil
}
func parseVarFiles(paths []string) ([]*hcl.File, hcl.Diagnostics) {
if len(paths) == 0 {
return nil, nil
}
files := make([]*hcl.File, 0, len(paths))
var diags hcl.Diagnostics
for _, p := range paths {
body, err := ioutil.ReadFile(p)
if err != nil {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Failed to read file",
Detail: fmt.Sprintf("failed to read %q: %v", p, err),
})
continue
}
var file *hcl.File
var mdiags hcl.Diagnostics
if !isJSON(body) {
file, mdiags = hclsyntax.ParseConfig(body, p, hcl.Pos{Line: 1, Column: 1})
} else {
file, mdiags = hcljson.Parse(body, p)
}
files = append(files, file)
diags = append(diags, mdiags...)
}
return files, diags
}
func isJSON(src []byte) bool {
for _, c := range src {
if c == ' ' {
continue
}
return c == '{'
}
return false
}