terraform/config/loader_libucl.go

529 lines
13 KiB
Go

package config
import (
"fmt"
"path/filepath"
"github.com/mitchellh/go-libucl"
)
// Put the parse flags we use for libucl in a constant so we can get
// equally behaving parsing everywhere.
const libuclParseFlags = libucl.ParserKeyLowercase
// libuclConfigurable is an implementation of configurable that knows
// how to turn libucl configuration into a *Config object.
type libuclConfigurable struct {
Object *libucl.Object
}
func (t *libuclConfigurable) Close() error {
return t.Object.Close()
}
func (t *libuclConfigurable) Config() (*Config, error) {
validKeys := map[string]struct{}{
"output": struct{}{},
"provider": struct{}{},
"resource": struct{}{},
"variable": struct{}{},
}
type LibuclVariable struct {
Default interface{}
Description string
Fields []string `libucl:",decodedFields"`
}
var rawConfig struct {
Variable map[string]*LibuclVariable
}
if err := t.Object.Decode(&rawConfig); err != nil {
return nil, err
}
// Start building up the actual configuration. We start with
// variables.
// TODO(mitchellh): Make function like loadVariablesLibucl so that
// duplicates aren't overriden
config := new(Config)
if len(rawConfig.Variable) > 0 {
config.Variables = make([]*Variable, 0, len(rawConfig.Variable))
for k, v := range rawConfig.Variable {
// Defaults turn into a slice of map[string]interface{} and
// we need to make sure to convert that down into the
// proper type for Config.
if ms, ok := v.Default.([]map[string]interface{}); ok {
def := make(map[string]interface{})
for _, m := range ms {
for k, v := range m {
def[k] = v
}
}
v.Default = def
}
newVar := &Variable{
Name: k,
Default: v.Default,
Description: v.Description,
}
config.Variables = append(config.Variables, newVar)
}
}
// Build the provider configs
providers := t.Object.Get("provider")
if providers != nil {
var err error
config.ProviderConfigs, err = loadProvidersLibucl(providers)
providers.Close()
if err != nil {
return nil, err
}
}
// Build the resources
resources := t.Object.Get("resource")
if resources != nil {
var err error
config.Resources, err = loadResourcesLibucl(resources)
resources.Close()
if err != nil {
return nil, err
}
}
// Build the outputs
if outputs := t.Object.Get("output"); outputs != nil {
var err error
config.Outputs, err = loadOutputsLibucl(outputs)
outputs.Close()
if err != nil {
return nil, err
}
}
// Check for invalid keys
iter := t.Object.Iterate(true)
defer iter.Close()
for o := iter.Next(); o != nil; o = iter.Next() {
k := o.Key()
o.Close()
if _, ok := validKeys[k]; ok {
continue
}
config.unknownKeys = append(config.unknownKeys, k)
}
return config, nil
}
// loadFileLibucl is a fileLoaderFunc that knows how to read libucl
// files and turn them into libuclConfigurables.
func loadFileLibucl(root string) (configurable, []string, error) {
var obj *libucl.Object = nil
// Parse and store the object. We don't use a defer here so that
// we clear resources right away rather than stack them up all the
// way through our recursive calls.
parser := libucl.NewParser(libuclParseFlags)
err := parser.AddFile(root)
if err == nil {
obj = parser.Object()
defer obj.Close()
}
parser.Close()
// If there was an error, return early
if err != nil {
return nil, nil, err
}
// Start building the result
result := &libuclConfigurable{
Object: obj,
}
// Otherwise, dive in, find the imports.
imports := obj.Get("import")
if imports == nil {
result.Object.Ref()
return result, nil, nil
}
if imports.Type() != libucl.ObjectTypeString {
imports.Close()
return nil, nil, fmt.Errorf(
"Error in %s: all 'import' declarations should be in the format\n"+
"`import \"foo\"` (Got type %s)",
root,
imports.Type())
}
// Gather all the import paths
importPaths := make([]string, 0, imports.Len())
iter := imports.Iterate(false)
for imp := iter.Next(); imp != nil; imp = iter.Next() {
path := imp.ToString()
if !filepath.IsAbs(path) {
// Relative paths are relative to the Terraform file itself
dir := filepath.Dir(root)
path = filepath.Join(dir, path)
}
importPaths = append(importPaths, path)
imp.Close()
}
iter.Close()
imports.Close()
result.Object.Ref()
return result, importPaths, nil
}
// LoadOutputsLibucl recurses into the given libucl object and turns
// it into a mapping of outputs.
func loadOutputsLibucl(o *libucl.Object) ([]*Output, error) {
objects := make(map[string]*libucl.Object)
// Iterate over all the "output" blocks and get the keys along with
// their raw configuration objects. We'll parse those later.
iter := o.Iterate(false)
for o1 := iter.Next(); o1 != nil; o1 = iter.Next() {
iter2 := o1.Iterate(true)
for o2 := iter2.Next(); o2 != nil; o2 = iter2.Next() {
objects[o2.Key()] = o2
defer o2.Close()
}
o1.Close()
iter2.Close()
}
iter.Close()
// If we have none, just return nil
if len(objects) == 0 {
return nil, nil
}
// Go through each object and turn it into an actual result.
result := make([]*Output, 0, len(objects))
for n, o := range objects {
var config map[string]interface{}
if err := o.Decode(&config); err != nil {
return nil, err
}
rawConfig, err := NewRawConfig(config)
if err != nil {
return nil, fmt.Errorf(
"Error reading config for output %s: %s",
n,
err)
}
result = append(result, &Output{
Name: n,
RawConfig: rawConfig,
})
}
return result, nil
}
// LoadProvidersLibucl recurses into the given libucl object and turns
// it into a mapping of provider configs.
func loadProvidersLibucl(o *libucl.Object) ([]*ProviderConfig, error) {
objects := make(map[string]*libucl.Object)
// Iterate over all the "provider" blocks and get the keys along with
// their raw configuration objects. We'll parse those later.
iter := o.Iterate(false)
for o1 := iter.Next(); o1 != nil; o1 = iter.Next() {
iter2 := o1.Iterate(true)
for o2 := iter2.Next(); o2 != nil; o2 = iter2.Next() {
objects[o2.Key()] = o2
defer o2.Close()
}
o1.Close()
iter2.Close()
}
iter.Close()
if len(objects) == 0 {
return nil, nil
}
// Go through each object and turn it into an actual result.
result := make([]*ProviderConfig, 0, len(objects))
for n, o := range objects {
var config map[string]interface{}
if err := o.Decode(&config); err != nil {
return nil, err
}
rawConfig, err := NewRawConfig(config)
if err != nil {
return nil, fmt.Errorf(
"Error reading config for provider config %s: %s",
n,
err)
}
result = append(result, &ProviderConfig{
Name: n,
RawConfig: rawConfig,
})
}
return result, nil
}
// Given a handle to a libucl object, this recurses into the structure
// and pulls out a list of resources.
//
// The resulting resources may not be unique, but each resource
// represents exactly one resource definition in the libucl configuration.
// We leave it up to another pass to merge them together.
func loadResourcesLibucl(o *libucl.Object) ([]*Resource, error) {
var allTypes []*libucl.Object
// Libucl object iteration is really nasty. Below is likely to make
// no sense to anyone approaching this code. Luckily, it is very heavily
// tested. If working on a bug fix or feature, we recommend writing a
// test first then doing whatever you want to the code below. If you
// break it, the tests will catch it. Likewise, if you change this,
// MAKE SURE you write a test for your change, because its fairly impossible
// to reason about this mess.
//
// Functionally, what the code does below is get the libucl.Objects
// for all the TYPES, such as "aws_security_group".
iter := o.Iterate(false)
for o1 := iter.Next(); o1 != nil; o1 = iter.Next() {
// Iterate the inner to get the list of types
iter2 := o1.Iterate(true)
for o2 := iter2.Next(); o2 != nil; o2 = iter2.Next() {
// Iterate all of this type to get _all_ the types
iter3 := o2.Iterate(false)
for o3 := iter3.Next(); o3 != nil; o3 = iter3.Next() {
allTypes = append(allTypes, o3)
}
o2.Close()
iter3.Close()
}
o1.Close()
iter2.Close()
}
iter.Close()
// Where all the results will go
var result []*Resource
// Now go over all the types and their children in order to get
// all of the actual resources.
for _, t := range allTypes {
// Release the resources for this raw type since we don't need it.
// Note that this makes it unsafe now to use allTypes again.
defer t.Close()
iter := t.Iterate(true)
defer iter.Close()
for r := iter.Next(); r != nil; r = iter.Next() {
defer r.Close()
var config map[string]interface{}
if err := r.Decode(&config); err != nil {
return nil, fmt.Errorf(
"Error reading config for %s[%s]: %s",
t.Key(),
r.Key(),
err)
}
// Remove the "count" from the config, since we treat that special
delete(config, "count")
// Delete the "provisioner" section from the config since
// that is treated specially.
delete(config, "provisioner")
// Delete the "connection" section since we handle that
// seperately
delete(config, "connection")
rawConfig, err := NewRawConfig(config)
if err != nil {
return nil, fmt.Errorf(
"Error reading config for %s[%s]: %s",
t.Key(),
r.Key(),
err)
}
// If we have a count, then figure it out
var count int = 1
if o := r.Get("count"); o != nil {
err = o.Decode(&count)
o.Close()
if err != nil {
return nil, fmt.Errorf(
"Error parsing count for %s[%s]: %s",
t.Key(),
r.Key(),
err)
}
}
// If we have connection info, then parse those out
var connInfo map[string]interface{}
if conn := r.Get("connection"); conn != nil {
var err error
connInfo, err = loadConnInfoLibucl(conn)
conn.Close()
if err != nil {
return nil, fmt.Errorf(
"Error reading connection info for %s[%s]: %s",
t.Key(),
r.Key(),
err)
}
}
// If we have provisioners, then parse those out
var provisioners []*Provisioner
if po := r.Get("provisioner"); po != nil {
var err error
provisioners, err = loadProvisionersLibucl(po, connInfo)
po.Close()
if err != nil {
return nil, fmt.Errorf(
"Error reading provisioners for %s[%s]: %s",
t.Key(),
r.Key(),
err)
}
}
result = append(result, &Resource{
Name: r.Key(),
Type: t.Key(),
Count: count,
RawConfig: rawConfig,
Provisioners: provisioners,
})
}
}
return result, nil
}
func loadProvisionersLibucl(o *libucl.Object, connInfo map[string]interface{}) ([]*Provisioner, error) {
pos := make([]*libucl.Object, 0, int(o.Len()))
// Accumulate all the actual provisioner configuration objects. We
// have to iterate twice here:
//
// 1. The first iteration is of the list of `provisioner` blocks.
// 2. The second iteration is of the dictionary within the
// provisioner which will have only one element which is the
// type of provisioner to use along with tis config.
//
// In JSON it looks kind of like this:
//
// [
// {
// "shell": {
// ...
// }
// }
// ]
//
iter := o.Iterate(false)
for o1 := iter.Next(); o1 != nil; o1 = iter.Next() {
iter2 := o1.Iterate(true)
for o2 := iter2.Next(); o2 != nil; o2 = iter2.Next() {
pos = append(pos, o2)
}
o1.Close()
iter2.Close()
}
iter.Close()
result := make([]*Provisioner, 0, len(pos))
for _, po := range pos {
defer po.Close()
var config map[string]interface{}
if err := po.Decode(&config); err != nil {
return nil, err
}
// Delete the "connection" section, handle seperately
delete(config, "connection")
rawConfig, err := NewRawConfig(config)
if err != nil {
return nil, err
}
// Check if we have a provisioner-level connection
// block that overrides the resource-level
var subConnInfo map[string]interface{}
if conn := po.Get("connection"); conn != nil {
var err error
subConnInfo, err = loadConnInfoLibucl(conn)
conn.Close()
if err != nil {
return nil, err
}
}
// Inherit from the resource connInfo any keys
// that are not explicitly overriden.
if connInfo != nil && subConnInfo != nil {
for k, v := range connInfo {
if _, ok := subConnInfo[k]; !ok {
subConnInfo[k] = v
}
}
} else if subConnInfo == nil {
subConnInfo = connInfo
}
// Parse the connInfo
connRaw, err := NewRawConfig(subConnInfo)
if err != nil {
return nil, err
}
result = append(result, &Provisioner{
Type: po.Key(),
RawConfig: rawConfig,
ConnInfo: connRaw,
})
}
return result, nil
}
func loadConnInfoLibucl(o *libucl.Object) (map[string]interface{}, error) {
var config map[string]interface{}
if err := o.Decode(&config); err != nil {
return nil, err
}
return config, nil
}