templates.go

package boilingcore

import (
	"crypto/sha256"
	"encoding"
	"encoding/base64"
	"fmt"
	"io/ioutil"
	"path/filepath"
	"sort"
	"strings"
	"text/template"

	"github.com/pkg/errors"
	"github.com/volatiletech/sqlboiler/drivers"
	"github.com/volatiletech/sqlboiler/strmangle"
	"github.com/volatiletech/sqlboiler/templatebin"
)

// templateData for sqlboiler templates
type templateData struct {
	Tables  []drivers.Table
	Table   drivers.Table
	Aliases Aliases

	// Controls what names are output
	PkgName string
	Schema  string

	// Helps tune the output
	DriverName string
	Dialect    drivers.Dialect

	// LQ and RQ contain a quoted quote that allows us to write
	// the templates more easily.
	LQ string
	RQ string

	// Control various generation features
	AddGlobal        bool
	AddPanic         bool
	NoContext        bool
	NoHooks          bool
	NoAutoTimestamps bool
	NoRowsAffected   bool

	// Tags control which tags are added to the struct
	Tags []string

	// Generate struct tags as camelCase or snake_case
	StructTagCasing string

	// StringFuncs are usable in templates with stringMap
	StringFuncs map[string]func(string) string
}

func (t templateData) Quotes(s string) string {
	return fmt.Sprintf("%s%s%s", t.LQ, s, t.RQ)
}

func (t templateData) SchemaTable(table string) string {
	return strmangle.SchemaTable(t.LQ, t.RQ, t.Dialect.UseSchema, t.Schema, table)
}

type templateList struct {
	*template.Template
}

type templateNameList []string

func (t templateNameList) Len() int {
	return len(t)
}

func (t templateNameList) Swap(k, j int) {
	t[k], t[j] = t[j], t[k]
}

func (t templateNameList) Less(k, j int) bool {
	// Make sure "struct" goes to the front
	if t[k] == "struct.tpl" {
		return true
	}

	res := strings.Compare(t[k], t[j])
	if res <= 0 {
		return true
	}

	return false
}

// Templates returns the name of all the templates defined in the template list
func (t templateList) Templates() []string {
	tplList := t.Template.Templates()

	if len(tplList) == 0 {
		return nil
	}

	ret := make([]string, 0, len(tplList))
	for _, tpl := range tplList {
		if name := tpl.Name(); strings.HasSuffix(name, ".tpl") {
			ret = append(ret, name)
		}
	}

	sort.Sort(templateNameList(ret))

	return ret
}

func loadTemplates(lazyTemplates []lazyTemplate, testTemplates bool) (*templateList, error) {
	tpl := template.New("")

	for _, t := range lazyTemplates {
		firstDir := strings.Split(t.Name, string(filepath.Separator))[0]
		isTest := strings.HasSuffix(firstDir, "_test")
		if testTemplates && !isTest || !testTemplates && isTest {
			continue
		}

		byt, err := t.Loader.Load()
		if err != nil {
			return nil, errors.Wrapf(err, "failed to load template: %s", t.Name)
		}

		_, err = tpl.New(t.Name).Funcs(templateFunctions).Parse(string(byt))
		if err != nil {
			return nil, errors.Wrapf(err, "failed to parse template: %s", t.Name)
		}
	}

	return &templateList{Template: tpl}, nil
}

type lazyTemplate struct {
	Name   string         `json:"name"`
	Loader templateLoader `json:"loader"`
}

type templateLoader interface {
	encoding.TextMarshaler
	Load() ([]byte, error)
}

type fileLoader string

func (f fileLoader) Load() ([]byte, error) {
	fname := string(f)
	b, err := ioutil.ReadFile(fname)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to load template: %s", fname)
	}
	return b, nil
}

func (f fileLoader) MarshalText() ([]byte, error) {
	return []byte(f.String()), nil
}

func (f fileLoader) String() string {
	return "file:" + string(f)
}

type base64Loader string

func (b base64Loader) Load() ([]byte, error) {
	byt, err := base64.StdEncoding.DecodeString(string(b))
	if err != nil {
		return nil, errors.Wrap(err, "failed to decode driver's template, should be base64)")
	}
	return byt, nil
}

func (b base64Loader) MarshalText() ([]byte, error) {
	return []byte(b.String()), nil
}

func (b base64Loader) String() string {
	byt, err := base64.StdEncoding.DecodeString(string(b))
	if err != nil {
		panic("trying to debug output base64 loader, but was not proper base64!")
	}
	sha := sha256.Sum256(byt)
	return fmt.Sprintf("base64:(sha256 of content): %x", sha)
}

type assetLoader string

func (a assetLoader) Load() ([]byte, error) {
	return templatebin.Asset(string(a))
}

func (a assetLoader) MarshalText() ([]byte, error) {
	return []byte(a.String()), nil
}

func (a assetLoader) String() string {
	return "asset:" + string(a)
}

// set is to stop duplication from named enums, allowing a template loop
// to keep some state
type once map[string]struct{}

func newOnce() once {
	return make(once)
}

func (o once) Has(s string) bool {
	_, ok := o[s]
	return ok
}

func (o once) Put(s string) bool {
	if _, ok := o[s]; ok {
		return false
	}

	o[s] = struct{}{}
	return true
}

// templateStringMappers are placed into the data to make it easy to use the
// stringMap function.
var templateStringMappers = map[string]func(string) string{
	// String ops
	"quoteWrap":       func(a string) string { return fmt.Sprintf(`"%s"`, a) },
	"replaceReserved": strmangle.ReplaceReservedWords,

	// Casing
	"titleCase": strmangle.TitleCase,
	"camelCase": strmangle.CamelCase,
}

// templateFunctions is a map of all the functions that get passed into the
// templates. If you wish to pass a new function into your own template,
// add a function pointer here.
var templateFunctions = template.FuncMap{
	// String ops
	"quoteWrap": func(s string) string { return fmt.Sprintf(`"%s"`, s) },
	"id":        strmangle.Identifier,

	// Pluralization
	"singular": strmangle.Singular,
	"plural":   strmangle.Plural,

	// Casing
	"titleCase": strmangle.TitleCase,
	"camelCase": strmangle.CamelCase,

	// String Slice ops
	"join":               func(sep string, slice []string) string { return strings.Join(slice, sep) },
	"joinSlices":         strmangle.JoinSlices,
	"stringMap":          strmangle.StringMap,
	"prefixStringSlice":  strmangle.PrefixStringSlice,
	"containsAny":        strmangle.ContainsAny,
	"generateTags":       strmangle.GenerateTags,
	"generateIgnoreTags": strmangle.GenerateIgnoreTags,

	// Enum ops
	"parseEnumName":       strmangle.ParseEnumName,
	"parseEnumVals":       strmangle.ParseEnumVals,
	"isEnumNormal":        strmangle.IsEnumNormal,
	"shouldTitleCaseEnum": strmangle.ShouldTitleCaseEnum,
	"onceNew":             newOnce,
	"oncePut":             once.Put,
	"onceHas":             once.Has,

	// String Map ops
	"makeStringMap": strmangle.MakeStringMap,

	// Set operations
	"setInclude": strmangle.SetInclude,

	// Database related mangling
	"whereClause": strmangle.WhereClause,

	// Alias and text helping
	"aliasCols":      func(ta TableAlias) func(string) string { return func(s string) string { return ta.Column(s) } },
	"usesPrimitives": usesPrimitives,

	// dbdrivers ops
	"filterColumnsByAuto":    drivers.FilterColumnsByAuto,
	"filterColumnsByDefault": drivers.FilterColumnsByDefault,
	"filterColumnsByEnum":    drivers.FilterColumnsByEnum,
	"sqlColDefinitions":      drivers.SQLColDefinitions,
	"columnNames":            drivers.ColumnNames,
	"columnDBTypes":          drivers.ColumnDBTypes,
	"getTable":               drivers.GetTable,
}