context.go

package main

import (
	"os"
	"path/filepath"
	"reflect"
	"strings"

	"github.com/coveo/gotemplate/errors"
	"github.com/coveo/gotemplate/utils"
)

func createContext(varsFiles []string, namedVars []string) (context map[string]interface{}) {
	context = map[string]interface{}{}

	type fileDef struct {
		name    string
		value   interface{}
		unnamed bool
	}

	nameValuePairs := make([]fileDef, 0, len(varsFiles)+len(namedVars))
	for i := range varsFiles {
		nameValuePairs = append(nameValuePairs, fileDef{value: varsFiles[i]})
	}

	for i := range namedVars {
		data := make(map[string]interface{})
		if err := utils.ConvertData(namedVars[i], &data); err != nil {
			var fd fileDef
			fd.name, fd.value = utils.Split2(namedVars[i], "=")
			if fd.value == "" {
				fd = fileDef{"", fd.name, true}
			}
			nameValuePairs = append(nameValuePairs, fd)
			continue
		}
		for key, value := range data {
			nameValuePairs = append(nameValuePairs, fileDef{key, value, false})
		}
	}

	for _, nv := range nameValuePairs {
		var loader func(string) (map[string]interface{}, error)
		filename, _ := reflect.ValueOf(nv.value).Interface().(string)
		if filename != "" {
			loader = func(filename string) (result map[string]interface{}, err error) {
				var content interface{}
				if err := utils.LoadData(filename, &content); err == nil {
					if content, isMap := content.(map[string]interface{}); isMap && nv.name == "" && !nv.unnamed {
						return content, nil
					}
					if nv.name == "" {
						nv.name = strings.TrimSuffix(filepath.Base(filename), filepath.Ext(filename))
					}
					return map[string]interface{}{nv.name: content}, nil
				} else if _, isFileErr := err.(*os.PathError); !isFileErr {
					return nil, err
				}
				if nv.name == "" {
					nv.name = "DEFAULT"
				}
				return map[string]interface{}{nv.name: nv.value}, nil
			}

			if filename == "-" {
				loader = func(filename string) (result map[string]interface{}, err error) {
					var content interface{}
					if err = utils.ConvertData(readStdin(), &content); err != nil {
						return nil, err
					}
					if content, isMap := content.(map[string]interface{}); isMap && nv.name == "" {
						return content, nil
					}
					if nv.name == "" {
						nv.name = "STDIN"
					}
					return map[string]interface{}{nv.name: content}, nil
				}
			}
		}

		if loader == nil {
			context[nv.name] = nv.value
			continue
		}
		content, err := loader(filename)
		if err != nil {
			errors.Raise("Error %v while loading vars file %s", nv.value, err)
		}
		for key, value := range content {
			context[key] = value
		}

		// There is no content
		if len(content) == 0 && nv.unnamed {
			errors.Raise("--var parameter must be a file or assignation (name=value) %s", nv.value)
		}
	}
	return
}