talm

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/*
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Copyright The Helm Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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    http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package engine
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import (
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	"bytes"
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	"encoding/json"
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	"strings"
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	"text/template"
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	"github.com/BurntSushi/toml"
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	"github.com/Masterminds/sprig/v3"
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	"sigs.k8s.io/yaml"
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)
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// funcMap returns a mapping of all of the functions that Engine has.
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//
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// Because some functions are late-bound (e.g. contain context-sensitive
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// data), the functions may not all perform identically outside of an Engine
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// as they will inside of an Engine.
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//
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// Known late-bound functions:
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//
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//   - "include"
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//   - "tpl"
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//
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// These are late-bound in Engine.Render().  The
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// version included in the FuncMap is a placeholder.
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func funcMap() template.FuncMap {
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	f := sprig.TxtFuncMap()
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	delete(f, "env")
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	delete(f, "expandenv")
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	// Add some extra functionality
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	extra := template.FuncMap{
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		"toToml":        toTOML,
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		"toYaml":        toYAML,
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		"fromYaml":      fromYAML,
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		"fromYamlArray": fromYAMLArray,
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		"toJson":        toJSON,
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		"fromJson":      fromJSON,
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		"fromJsonArray": fromJSONArray,
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		// This is a placeholder for the "include" function, which is
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		// late-bound to a template. By declaring it here, we preserve the
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		// integrity of the linter.
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		"include":  func(string, interface{}) string { return "not implemented" },
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		"tpl":      func(string, interface{}) interface{} { return "not implemented" },
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		"required": func(string, interface{}) (interface{}, error) { return "not implemented", nil },
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		// Provide a placeholder for the "lookup" function, which requires a kubernetes
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		// connection.
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		"lookup": func(string, string, string, string) (map[string]interface{}, error) {
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			return map[string]interface{}{}, nil
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		},
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	}
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	for k, v := range extra {
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		f[k] = v
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	}
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	return f
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}
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// toYAML takes an interface, marshals it to yaml, and returns a string. It will
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// always return a string, even on marshal error (empty string).
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//
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// This is designed to be called from a template.
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func toYAML(v interface{}) string {
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	data, err := yaml.Marshal(v)
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	if err != nil {
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		// Swallow errors inside of a template.
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		return ""
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	}
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	return strings.TrimSuffix(string(data), "\n")
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}
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// fromYAML converts a YAML document into a map[string]interface{}.
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//
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// This is not a general-purpose YAML parser, and will not parse all valid
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// YAML documents. Additionally, because its intended use is within templates
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// it tolerates errors. It will insert the returned error message string into
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// m["Error"] in the returned map.
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func fromYAML(str string) map[string]interface{} {
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	m := map[string]interface{}{}
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	if err := yaml.Unmarshal([]byte(str), &m); err != nil {
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		m["Error"] = err.Error()
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	}
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	return m
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}
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// fromYAMLArray converts a YAML array into a []interface{}.
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//
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// This is not a general-purpose YAML parser, and will not parse all valid
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// YAML documents. Additionally, because its intended use is within templates
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// it tolerates errors. It will insert the returned error message string as
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// the first and only item in the returned array.
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func fromYAMLArray(str string) []interface{} {
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	a := []interface{}{}
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	if err := yaml.Unmarshal([]byte(str), &a); err != nil {
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		a = []interface{}{err.Error()}
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	}
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	return a
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}
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// toTOML takes an interface, marshals it to toml, and returns a string. It will
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// always return a string, even on marshal error (empty string).
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//
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// This is designed to be called from a template.
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func toTOML(v interface{}) string {
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	b := bytes.NewBuffer(nil)
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	e := toml.NewEncoder(b)
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	err := e.Encode(v)
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	if err != nil {
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		return err.Error()
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	}
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	return b.String()
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}
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// toJSON takes an interface, marshals it to json, and returns a string. It will
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// always return a string, even on marshal error (empty string).
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//
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// This is designed to be called from a template.
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func toJSON(v interface{}) string {
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	data, err := json.Marshal(v)
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	if err != nil {
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		// Swallow errors inside of a template.
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		return ""
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	}
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	return string(data)
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}
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// fromJSON converts a JSON document into a map[string]interface{}.
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//
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// This is not a general-purpose JSON parser, and will not parse all valid
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// JSON documents. Additionally, because its intended use is within templates
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// it tolerates errors. It will insert the returned error message string into
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// m["Error"] in the returned map.
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func fromJSON(str string) map[string]interface{} {
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	m := make(map[string]interface{})
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	if err := json.Unmarshal([]byte(str), &m); err != nil {
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		m["Error"] = err.Error()
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	}
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	return m
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}
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// fromJSONArray converts a JSON array into a []interface{}.
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//
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// This is not a general-purpose JSON parser, and will not parse all valid
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// JSON documents. Additionally, because its intended use is within templates
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// it tolerates errors. It will insert the returned error message string as
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// the first and only item in the returned array.
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func fromJSONArray(str string) []interface{} {
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	a := []interface{}{}
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	if err := json.Unmarshal([]byte(str), &a); err != nil {
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		a = []interface{}{err.Error()}
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	}
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	return a
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}
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