094d3a0817
This change includes some progress on actual compilation (albeit with several TODOs remaining before we can actually spit out a useful artifact). There are also some general cleanups sprinkled throughout. In a nutshell: * Add a compiler.Context object that will be available during template expansion. * Introduce a diag.Document abstraction. This is better than passing raw filenames around, and lets us embellish diagnostics as we go. In particular, we will be in a better position to provide line/column error information. * Move IO out of the Parser and into the Compiler, where it can cache and reuse Documents. This will become important as we start to load up dependencies. * Rename PosRange to Location. This reads nicer with the new Document terminology. * Rename the mu/api package to mu/schema. It's likely we will need to introduce a true AST that is decoupled from the serialization format and contains bound nodes. As a result, treating the existing types as "schema" is more honest. * Add in a big section of TODOs at the end of the compiler.Compiler.Build function.
77 lines
2.1 KiB
Go
77 lines
2.1 KiB
Go
// Copyright 2016 Marapongo, Inc. All rights reserved.
|
|
|
|
package compiler
|
|
|
|
import (
|
|
"encoding/json"
|
|
|
|
"github.com/ghodss/yaml"
|
|
"github.com/golang/glog"
|
|
|
|
"github.com/marapongo/mu/pkg/diag"
|
|
"github.com/marapongo/mu/pkg/errors"
|
|
"github.com/marapongo/mu/pkg/schema"
|
|
)
|
|
|
|
type Parser interface {
|
|
// Diag fetches the diagnostics sink used by this parser.
|
|
Diag() diag.Sink
|
|
|
|
// Parse detects and parses input from the given path. If an error occurs, the return value will be nil. It is
|
|
// expected that errors are conveyed using the diag.Sink interface.
|
|
Parse(doc *diag.Document) *schema.Stack
|
|
}
|
|
|
|
func NewParser(c Compiler) Parser {
|
|
return &parser{c}
|
|
}
|
|
|
|
type parser struct {
|
|
c Compiler
|
|
}
|
|
|
|
func (p *parser) Diag() diag.Sink {
|
|
return p.c.Diag()
|
|
}
|
|
|
|
func (p *parser) Parse(doc *diag.Document) *schema.Stack {
|
|
glog.Infof("Parsing Mufile: %v (len(body)=%v)", doc.File, len(doc.Body))
|
|
if glog.V(2) {
|
|
defer func() {
|
|
glog.V(2).Infof("Parsing Mufile '%v' completed w/ %v warnings and %v errors",
|
|
doc.File, p.Diag().Warnings(), p.Diag().Errors())
|
|
}()
|
|
}
|
|
|
|
// We support both JSON and YAML as a file format. Detect the file extension and deserialize the contents.
|
|
// TODO: we need to expand templates as part of the parsing process.
|
|
switch doc.Ext() {
|
|
case ".json":
|
|
return p.parseFromJSON(doc)
|
|
case ".yaml":
|
|
return p.parseFromYAML(doc)
|
|
default:
|
|
p.Diag().Errorf(errors.IllegalMufileExt.WithDocument(doc), doc.Ext())
|
|
return nil
|
|
}
|
|
}
|
|
|
|
func (p *parser) parseFromJSON(doc *diag.Document) *schema.Stack {
|
|
var stack schema.Stack
|
|
if err := json.Unmarshal(doc.Body, &stack); err != nil {
|
|
p.Diag().Errorf(errors.IllegalMufileSyntax.WithDocument(doc), err)
|
|
// TODO: it would be great if we issued an error per issue found in the file with line/col numbers.
|
|
return nil
|
|
}
|
|
return &stack
|
|
}
|
|
|
|
func (p *parser) parseFromYAML(doc *diag.Document) *schema.Stack {
|
|
var stack schema.Stack
|
|
if err := yaml.Unmarshal(doc.Body, &stack); err != nil {
|
|
p.Diag().Errorf(errors.IllegalMufileSyntax.WithDocument(doc), err)
|
|
// TODO: it would be great if we issued an error per issue found in the file with line/col numbers.
|
|
return nil
|
|
}
|
|
return &stack
|
|
}
|