neoneo-go/pkg/smartcontract/binding/generate.go
Evgeniy Stratonikov da03d895de cli/smartcontract: generate bindings to an existing contract
Signed-off-by: Evgeniy Stratonikov <evgeniy@nspcc.ru>
2022-02-23 15:40:06 +03:00

254 lines
6.4 KiB
Go

package binding
import (
"bytes"
"fmt"
"io"
"sort"
"strconv"
"strings"
"text/template"
"unicode"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/util"
)
const srcTmpl = `
{{- define "METHOD" -}}
// {{.Name}} {{.Comment}}
func {{.Name}}({{range $index, $arg := .Arguments -}}
{{- if ne $index 0}}, {{end}}
{{- .Name}} {{.Type}}
{{- end}}) {{if .ReturnType }}{{ .ReturnType }} {
return neogointernal.CallWithToken(Hash, "{{ .NameABI }}", int(contract.{{ .CallFlag }})
{{- range $arg := .Arguments -}}, {{.Name}}{{end}}).({{ .ReturnType }})
{{- else -}} {
neogointernal.CallWithTokenNoRet(Hash, "{{ .NameABI }}", int(contract.{{ .CallFlag }})
{{- range $arg := .Arguments -}}, {{.Name}}{{end}})
{{- end}}
}
{{- end -}}
// Package {{.PackageName}} contains wrappers for {{.ContractName}} contract.
package {{.PackageName}}
import (
{{range $m := .Imports}} "{{ $m }}"
{{end}})
// Hash contains contract hash in big-endian form.
const Hash = "{{ .Hash }}"
{{range $m := .Methods}}
{{template "METHOD" $m }}
{{end}}`
type (
// Config contains parameter for the generated binding.
Config struct {
Package string `yaml:"package,omitempty"`
Manifest *manifest.Manifest `yaml:"-"`
Hash util.Uint160 `yaml:"hash,omitempty"`
Overrides map[string]Override `yaml:"overrides,omitempty"`
CallFlags map[string]callflag.CallFlag `yaml:"callflags,omitempty"`
Output io.Writer `yaml:"-"`
}
contractTmpl struct {
PackageName string
ContractName string
Imports []string
Hash string
Methods []methodTmpl
}
methodTmpl struct {
Name string
NameABI string
CallFlag string
Comment string
Arguments []paramTmpl
ReturnType string
}
paramTmpl struct {
Name string
Type string
}
)
// NewConfig initializes and returns new config instance.
func NewConfig() Config {
return Config{
Overrides: make(map[string]Override),
CallFlags: make(map[string]callflag.CallFlag),
}
}
// Generate writes Go file containing smartcontract bindings to the `cfg.Output`.
func Generate(cfg Config) error {
ctr, err := templateFromManifest(cfg)
if err != nil {
return err
}
tmp, err := template.New("generate").Funcs(template.FuncMap{
"lowerFirst": lowerFirst,
"scTypeToGo": scTypeToGo,
}).Parse(srcTmpl)
if err != nil {
return err
}
return tmp.Execute(cfg.Output, ctr)
}
func scTypeToGo(typ smartcontract.ParamType) string {
switch typ {
case smartcontract.AnyType:
return "interface{}"
case smartcontract.BoolType:
return "bool"
case smartcontract.IntegerType:
return "int"
case smartcontract.ByteArrayType:
return "[]byte"
case smartcontract.StringType:
return "string"
case smartcontract.Hash160Type:
return "interop.Hash160"
case smartcontract.Hash256Type:
return "interop.Hash256"
case smartcontract.PublicKeyType:
return "interop.PublicKey"
case smartcontract.SignatureType:
return "interop.Signature"
case smartcontract.ArrayType:
return "[]interface{}"
case smartcontract.MapType:
return "map[string]interface{}"
case smartcontract.InteropInterfaceType:
return "interface{}"
case smartcontract.VoidType:
return ""
default:
panic("unreachable")
}
}
func templateFromManifest(cfg Config) (contractTmpl, error) {
hStr := ""
for _, b := range cfg.Hash.BytesBE() {
hStr += fmt.Sprintf("\\x%02x", b)
}
ctr := contractTmpl{
PackageName: cfg.Package,
ContractName: cfg.Manifest.Name,
Hash: hStr,
}
if ctr.PackageName == "" {
buf := bytes.NewBuffer(make([]byte, 0, len(cfg.Manifest.Name)))
for _, r := range cfg.Manifest.Name {
if unicode.IsLetter(r) {
buf.WriteRune(unicode.ToLower(r))
}
}
ctr.PackageName = buf.String()
}
imports := make(map[string]struct{})
seen := make(map[string]bool)
for _, m := range cfg.Manifest.ABI.Methods {
seen[m.Name] = false
}
for _, m := range cfg.Manifest.ABI.Methods {
if m.Name[0] == '_' {
continue
}
imports["github.com/nspcc-dev/neo-go/pkg/interop/contract"] = struct{}{}
imports["github.com/nspcc-dev/neo-go/pkg/interop/neogointernal"] = struct{}{}
// Consider `perform(a)` and `perform(a, b)` methods.
// First, try to export the second method with `Perform2` name.
// If `perform2` is already in the manifest, use `perform_2` with as many underscores
// as needed to eliminate name conflicts. It will produce long names in certain circumstances,
// but if the manifest contains lots of similar names with trailing underscores, delicate naming
// was probably not the goal.
name := m.Name
if v, ok := seen[name]; !ok || v {
suffix := strconv.Itoa(len(m.Parameters))
for ; seen[name]; name = m.Name + suffix {
suffix = "_" + suffix
}
}
seen[name] = true
mtd := methodTmpl{
Name: upperFirst(name),
NameABI: m.Name,
CallFlag: callflag.All.String(),
Comment: fmt.Sprintf("invokes `%s` method of contract.", m.Name),
}
if f, ok := cfg.CallFlags[m.Name]; ok {
mtd.CallFlag = f.String()
} else if m.Safe {
mtd.CallFlag = callflag.ReadOnly.String()
}
for i := range m.Parameters {
name := m.Parameters[i].Name
if name == "" {
name = fmt.Sprintf("arg%d", i)
}
var typeStr string
if over, ok := cfg.Overrides[m.Name+"."+name]; ok {
typeStr = over.TypeName
if over.Package != "" {
imports[over.Package] = struct{}{}
}
} else {
typeStr = scTypeToGo(m.Parameters[i].Type)
}
mtd.Arguments = append(mtd.Arguments, paramTmpl{
Name: name,
Type: typeStr,
})
}
if over, ok := cfg.Overrides[m.Name]; ok {
mtd.ReturnType = over.TypeName
if over.Package != "" {
imports[over.Package] = struct{}{}
}
} else {
mtd.ReturnType = scTypeToGo(m.ReturnType)
switch m.ReturnType {
case smartcontract.Hash160Type, smartcontract.Hash256Type, smartcontract.InteropInterfaceType,
smartcontract.SignatureType, smartcontract.PublicKeyType:
imports["github.com/nspcc-dev/neo-go/pkg/interop"] = struct{}{}
}
}
ctr.Methods = append(ctr.Methods, mtd)
}
for imp := range imports {
ctr.Imports = append(ctr.Imports, imp)
}
sort.Strings(ctr.Imports)
return ctr, nil
}
func upperFirst(s string) string {
return strings.ToUpper(s[0:1]) + s[1:]
}
func lowerFirst(s string) string {
return strings.ToLower(s[0:1]) + s[1:]
}