func MakeFnWith(sources *deepstack.DeepStack, outerRules *template.Rules) template.Rule {
return func(path []interface{}, node interface{}) (interface{}, interface{}) {
key := interface{}(nil)
if len(path) > 0 {
key = path[len(path)-1]
}
raw, ok := singleKey(node, "Fn::With")
if !ok {
return key, node //passthru
}
args, ok := collectArgs(
raw,
func(argsSoFar []interface{}) bool {
return len(argsSoFar) < 2
},
func(argsSoFar []interface{}, arg interface{}) (bool, interface{}) {
// unconditionally process the argument, in case it needs to be skipped
key, node := template.Walk(path, arg, outerRules)
if skip, ok := key.(bool); ok && skip {
return true, nil
}
if len(argsSoFar) == 1 {
return false, arg // return unprocessed 2nd arg. It's a template.
}
return false, node
},
)
if !ok {
return key, node //passthru
}
var source map[string]interface{}
if source, ok = args[0].(map[string]interface{}); !ok {
return key, node //passthru
}
sources.Push(fallbackmap.DeepMap(source))
innerTemplate := interface{}(args[1])
key, generated := template.Walk(path, innerTemplate, outerRules)
sources.PopDiscard()
return key, interface{}(generated)
}
}
func MakeRef(sources fallbackmap.Deep, rules *template.Rules) template.Rule {
return func(path []interface{}, node interface{}) (interface{}, interface{}) {
key := interface{}(nil)
if len(path) > 0 {
key = path[len(path)-1]
}
argInterface, ok := singleKey(node, "Ref")
if !ok {
return key, node //passthru
}
var argString string
if argString, ok = argInterface.(string); !ok {
return key, node //passthru
}
var refpath []string
for _, part := range deepalias.Split(argString) {
refpath = append(refpath, part)
}
var newNode interface{}
newNode, ok = sources.Get(refpath)
if ok {
var newKey interface{}
newKey, newNode = template.Walk(path, newNode, rules)
return newKey, newNode
}
return key, node //passthru (ref not found)
}
}
func (lazy LazyMap) Get(path []string) (value interface{}, has_key bool) {
if len(path) == 0 {
return lazy, true
}
processed, ok := lazy.processed[strings.Join(path, ".")]
if ok {
value, has_key = processed.Get(path)
if has_key {
lazy.processed[strings.Join(path, ".")] = fallbackmap.NewDeepSingle(path, value)
return value, true
}
lazy.processed[strings.Join(path, ".")] = fallbackmap.DeepNil
return nil, false
}
value, has_key = lazy.deep.Get(path)
if has_key {
var newKey interface{}
newKey, value = template.Walk([]interface{}{path[len(path)-1]}, value, lazy.rules)
if newKey == nil {
return nil, false
}
if newKey == path[len(path)-1] {
lazy.processed[strings.Join(path, ".")] = fallbackmap.NewDeepSingle(path, value)
return value, true
}
return nil, false
}
if len(path) == 1 {
return nil, false
}
head := path[:len(path)-1]
_, has_key = lazy.Get(head)
if has_key {
value, has_key = lazy.processed[strings.Join(head, ".")].Get(path)
if has_key {
lazy.processed[strings.Join(path, ".")] = fallbackmap.NewDeepSingle(path, value)
return value, true
}
}
return nil, false
}
func MakeFnIncludeFile(opener vfs.Opener, rules *template.Rules) template.Rule {
return func(path []interface{}, node interface{}) (interface{}, interface{}) {
key := interface{}(nil)
if len(path) > 0 {
key = path[len(path)-1]
}
argInterface, ok := singleKey(node, "Fn::IncludeFile")
if !ok {
return key, node //passthru
}
var argString string
if argString, ok = argInterface.(string); !ok {
return key, node //passthru
}
var absPath string
var err error
if absPath, err = filepath.Abs(argString); err != nil {
panic(fmt.Errorf("Error opening imported file '%s': %s", argString, err))
}
var jsonStream io.Reader
if jsonStream, err = opener.Open(absPath); err != nil {
panic(fmt.Errorf("Error opening imported file '%s': %s", absPath, err))
}
dec := json.NewDecoder(jsonStream)
includedTemplate := interface{}(nil)
if err := dec.Decode(&includedTemplate); err != nil {
panic(fmt.Errorf("Error loading imported file '%s': %s", argString, err))
}
key, generated := template.Walk(path, includedTemplate, rules)
return key, interface{}(generated)
}
}
func MakeFnFor(sources *deepstack.DeepStack, templateRules *template.Rules) template.Rule {
return func(path []interface{}, node interface{}) (interface{}, interface{}) {
key := interface{}(nil)
if len(path) > 0 {
key = path[len(path)-1]
}
raw, ok := singleKey(node, "Fn::For")
if !ok {
return key, node //passthru
}
args, ok := collectArgs(
raw,
func(argsSoFar []interface{}) bool { return len(argsSoFar) < 3 },
func(argsSoFar []interface{}, arg interface{}) (skip bool, newNode interface{}) {
// unconditionally process the argument, in case it needs to be skipped
key, node := template.Walk(path, arg, templateRules)
if skip, ok := key.(bool); ok && skip {
return true, nil
}
if len(argsSoFar) == 2 {
return false, arg // return unprocessed 3rd arg. It's a template.
}
return false, node
},
)
if !ok {
return key, node //passthru
}
var refNames []interface{}
var refName interface{}
if refNames, ok = args[0].([]interface{}); ok {
if len(refNames) == 1 {
refNames = []interface{}{nil, refNames[0]}
} else if len(refNames) != 2 {
return key, node //passthru
}
} else {
refNames = []interface{}{nil, args[0]}
}
for _, refName = range refNames {
if _, ok = refName.(string); !ok && refName != nil {
return key, node //passthru
}
}
valuesInterface := args[1]
var values []interface{}
if values, ok = valuesInterface.([]interface{}); !ok {
return key, node //passthru
}
loopTemplate := interface{}(args[2])
generated := []interface{}{}
for deepIndex, value := range values {
refMap := make(map[string]interface{})
if refNames[0] != nil {
refMap[refNames[0].(string)] = float64(deepIndex)
}
if refNames[1] != nil {
refMap[refNames[1].(string)] = value
}
deepPath := make([]interface{}, len(path)+1)
copy(deepPath, path)
deepPath[cap(deepPath)-1] = interface{}(deepIndex)
sources.Push(fallbackmap.DeepMap(refMap))
newIndex, processed := template.Walk(deepPath, loopTemplate, templateRules)
sources.PopDiscard()
if newIndex != nil {
generated = append(generated, processed)
}
}
return key, interface{}(generated)
}
}
