ipld-eth-server/pkg/plugin/writer/writer.go
2019-02-24 21:38:47 -06:00

93 lines
2.8 KiB
Go

// VulcanizeDB
// Copyright © 2018 Vulcanize
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package writer
import (
"errors"
"fmt"
. "github.com/dave/jennifer/jen"
"github.com/vulcanize/vulcanizedb/pkg/config"
"github.com/vulcanize/vulcanizedb/pkg/plugin/helpers"
)
type PluginWriter interface {
WritePlugin() error
}
type writer struct {
GenConfig config.Plugin
}
func NewPluginWriter(gc config.Plugin) *writer {
return &writer{
GenConfig: gc,
}
}
// Generates the plugin code
func (w *writer) WritePlugin() error {
// Setup plugin file paths
goFile, err := w.setupFilePath()
if err != nil {
return err
}
// Begin code generation
f := NewFile("main")
f.HeaderComment("This is a plugin generated to export the configured transformer initializers")
// Import TransformerInitializers specified in config
f.ImportAlias("github.com/vulcanize/vulcanizedb/libraries/shared/transformer", "interface")
for alias, imp := range w.GenConfig.Initializers {
f.ImportAlias(imp, alias)
}
// Collect TransformerInitializer names
importedInitializers := make([]Code, 0, len(w.GenConfig.Initializers))
for _, path := range w.GenConfig.Initializers {
importedInitializers = append(importedInitializers, Qual(path, "TransformerInitializer"))
}
// Create Exporter variable with method to export the set of the imported TransformerInitializers
f.Type().Id("exporter").String()
f.Var().Id("Exporter").Id("exporter")
f.Func().Params(Id("e").Id("exporter")).Id("Export").Params().Index().Qual(
"github.com/vulcanize/vulcanizedb/libraries/shared/transformer",
"TransformerInitializer").Block(
Return(Index().Qual(
"github.com/vulcanize/vulcanizedb/libraries/shared/transformer",
"TransformerInitializer").Values(importedInitializers...))) // Exports the collected TransformerInitializers
// Write code to destination file
err = f.Save(goFile)
if err != nil {
return errors.New(fmt.Sprintf("failed to save generated .go file: %s\r\n%s", goFile, err.Error()))
}
return nil
}
func (w *writer) setupFilePath() (string, error) {
goFile, soFile, err := w.GenConfig.GetPluginPaths()
if err != nil {
return "", err
}
// Clear .go and .so files of the same name if they exist
return goFile, helpers.ClearFiles(goFile, soFile)
}