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Use go/ast for adding coredns (#228)

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Use the package go/ast/astutil for adding CoreDNS to caddy and removing
the http server stuff from it as well - we're only a DNS server, no need
to caddy all the HTTP stuff as well.

Results in smaller binary and plugin_generate.go being much smaller as
well.
This commit is contained in:
Miek Gieben 2016-08-21 14:48:54 +01:00 • committed by GitHub
parent 26f52a99d9
commit 08ca048a35
1 changed files with 17 additions and 50 deletions
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67
plugin_generate.go
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@ -4,55 +4,16 @@ package main
import (
"bytes"
"errors"
"go/ast"
"go/parser"
"go/printer"
"go/token"
"io/ioutil"
"log"
"strconv"
"golang.org/x/tools/go/ast/astutil"
)
func AddImportToFile(file, imprt string) ([]byte, error) {
fset := token.NewFileSet()
f, err := parser.ParseFile(fset, file, nil, parser.ParseComments)
if err != nil {
return nil, err
}
for _, s := range f.Imports {
iSpec := &ast.ImportSpec{Path: &ast.BasicLit{Value: s.Path.Value}}
if iSpec.Path.Value == strconv.Quote(imprt) {
return nil, errors.New("coredns import already found")
}
}
for i := 0; i < len(f.Decls); i++ {
d := f.Decls[i]
switch d.(type) {
case *ast.FuncDecl:
// No action
case *ast.GenDecl:
dd := d.(*ast.GenDecl)
// IMPORT Declarations
if dd.Tok == token.IMPORT {
// Add the new import
iSpec := &ast.ImportSpec{Name: &ast.Ident{Name: "_"}, Path: &ast.BasicLit{Value: strconv.Quote(imprt)}}
dd.Specs = append(dd.Specs, iSpec)
break
}
}
}
ast.SortImports(fset, f)
out, err := GenerateFile(fset, f)
return out, err
}
func GenerateFile(fset *token.FileSet, file *ast.File) ([]byte, error) {
var output []byte
buffer := bytes.NewBuffer(output)
@ -63,19 +24,25 @@ func GenerateFile(fset *token.FileSet, file *ast.File) ([]byte, error) {
return buffer.Bytes(), nil
}
const (
coredns = "github.com/miekg/coredns/core"
// If everything is OK and we are sitting in CoreDNS' dir, this is where run.go should be.
caddyrun = "../../mholt/caddy/caddy/caddymain/run.go"
)
func main() {
out, err := AddImportToFile(caddyrun, coredns)
fset := token.NewFileSet()
f, err := parser.ParseFile(fset, caddyrun, nil, parser.ParseComments)
if err != nil {
log.Printf("failed to add import: %s", err)
return
log.Fatalf("failed to parse %s: %s", caddyrun, err)
}
astutil.AddNamedImport(fset, f, "_", coredns)
astutil.DeleteNamedImport(fset, f, "_", caddy)
out, err := GenerateFile(fset, f)
if err := ioutil.WriteFile(caddyrun, out, 0644); err != nil {
log.Fatalf("failed to write go file: %s", err)
}
}
const (
coredns = "github.com/miekg/coredns/core"
caddy = "github.com/mholt/caddy/caddyhttp"
// If everything is OK and we are sitting in CoreDNS' dir, this is where run.go should be.
caddyrun = "../../mholt/caddy/caddy/caddymain/run.go"
)