package funcs import ( "fmt" "regexp" "sort" "strings" "github.com/zclconf/go-cty/cty" "github.com/zclconf/go-cty/cty/function" "github.com/zclconf/go-cty/cty/gocty" ) var JoinFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "separator", Type: cty.String, }, }, VarParam: &function.Parameter{ Name: "lists", Type: cty.List(cty.String), }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) { sep := args[0].AsString() listVals := args[1:] if len(listVals) < 1 { return cty.UnknownVal(cty.String), fmt.Errorf("at least one list is required") } l := 0 for _, list := range listVals { if !list.IsWhollyKnown() { return cty.UnknownVal(cty.String), nil } l += list.LengthInt() } items := make([]string, 0, l) for _, list := range listVals { for it := list.ElementIterator(); it.Next(); { _, val := it.Element() items = append(items, val.AsString()) } } return cty.StringVal(strings.Join(items, sep)), nil }, }) var SortFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "list", Type: cty.List(cty.String), }, }, Type: function.StaticReturnType(cty.List(cty.String)), Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) { listVal := args[0] if !listVal.IsWhollyKnown() { // If some of the element values aren't known yet then we // can't yet preduct the order of the result. return cty.UnknownVal(retType), nil } if listVal.LengthInt() == 0 { // Easy path return listVal, nil } list := make([]string, 0, listVal.LengthInt()) for it := listVal.ElementIterator(); it.Next(); { iv, v := it.Element() if v.IsNull() { return cty.UnknownVal(retType), fmt.Errorf("given list element %s is null; a null string cannot be sorted", iv.AsBigFloat().String()) } list = append(list, v.AsString()) } sort.Strings(list) retVals := make([]cty.Value, len(list)) for i, s := range list { retVals[i] = cty.StringVal(s) } return cty.ListVal(retVals), nil }, }) var SplitFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "separator", Type: cty.String, }, { Name: "str", Type: cty.String, }, }, Type: function.StaticReturnType(cty.List(cty.String)), Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) { sep := args[0].AsString() str := args[1].AsString() elems := strings.Split(str, sep) elemVals := make([]cty.Value, len(elems)) for i, s := range elems { elemVals[i] = cty.StringVal(s) } if len(elemVals) == 0 { return cty.ListValEmpty(cty.String), nil } return cty.ListVal(elemVals), nil }, }) // ChompFunc constructions a function that removes newline characters at the end of a string. var ChompFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "str", Type: cty.String, }, }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) { newlines := regexp.MustCompile(`(?:\r\n?|\n)*\z`) return cty.StringVal(newlines.ReplaceAllString(args[0].AsString(), "")), nil }, }) // IndentFunc constructions a function that adds a given number of spaces to the // beginnings of all but the first line in a given multi-line string. var IndentFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "spaces", Type: cty.Number, }, { Name: "str", Type: cty.String, }, }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) { var spaces int if err := gocty.FromCtyValue(args[0], &spaces); err != nil { return cty.UnknownVal(cty.String), err } data := args[1].AsString() pad := strings.Repeat(" ", spaces) return cty.StringVal(strings.Replace(data, "\n", "\n"+pad, -1)), nil }, }) // ReplaceFunc constructions a function that searches a given string for another // given substring, and replaces each occurence with a given replacement string. var ReplaceFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "str", Type: cty.String, }, { Name: "substr", Type: cty.String, }, { Name: "replace", Type: cty.String, }, }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) { str := args[0].AsString() substr := args[1].AsString() replace := args[2].AsString() // We search/replace using a regexp if the string is surrounded // in forward slashes. if len(substr) > 1 && substr[0] == '/' && substr[len(substr)-1] == '/' { re, err := regexp.Compile(substr[1 : len(substr)-1]) if err != nil { return cty.UnknownVal(cty.String), err } return cty.StringVal(re.ReplaceAllString(str, replace)), nil } return cty.StringVal(strings.Replace(str, substr, replace, -1)), nil }, }) // TitleFunc constructions a function that converts the first letter of each word // in the given string to uppercase. var TitleFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "str", Type: cty.String, }, }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) { return cty.StringVal(strings.Title(args[0].AsString())), nil }, }) // TrimSpaceFunc constructions a function that removes any space characters from // the start and end of the given string. var TrimSpaceFunc = function.New(&function.Spec{ Params: []function.Parameter{ { Name: "str", Type: cty.String, }, }, Type: function.StaticReturnType(cty.String), Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) { return cty.StringVal(strings.TrimSpace(args[0].AsString())), nil }, }) // Join concatenates together the string elements of one or more lists with a // given separator. func Join(sep cty.Value, lists ...cty.Value) (cty.Value, error) { args := make([]cty.Value, len(lists)+1) args[0] = sep copy(args[1:], lists) return JoinFunc.Call(args) } // Sort re-orders the elements of a given list of strings so that they are // in ascending lexicographical order. func Sort(list cty.Value) (cty.Value, error) { return SortFunc.Call([]cty.Value{list}) } // Split divides a given string by a given separator, returning a list of // strings containing the characters between the separator sequences. func Split(sep, str cty.Value) (cty.Value, error) { return SplitFunc.Call([]cty.Value{sep, str}) } // Chomp removes newline characters at the end of a string. func Chomp(str cty.Value) (cty.Value, error) { return ChompFunc.Call([]cty.Value{str}) } // Indent adds a given number of spaces to the beginnings of all but the first // line in a given multi-line string. func Indent(spaces, str cty.Value) (cty.Value, error) { return IndentFunc.Call([]cty.Value{spaces, str}) } // Replace searches a given string for another given substring, // and replaces all occurences with a given replacement string. func Replace(str, substr, replace cty.Value) (cty.Value, error) { return ReplaceFunc.Call([]cty.Value{str, substr, replace}) } // Title converts the first letter of each word in the given string to uppercase. func Title(str cty.Value) (cty.Value, error) { return TitleFunc.Call([]cty.Value{str}) } // TrimSpace removes any space characters from the start and end of the given string. func TrimSpace(str cty.Value) (cty.Value, error) { return TrimSpaceFunc.Call([]cty.Value{str}) }