feat: add 7.x source code

pkg/modules/pdfengines/pdfengines.go

@@ -0,0 +1,160 @@
+package pdfengines
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/gotenberg/gotenberg/v7/pkg/gotenberg"
+	"github.com/gotenberg/gotenberg/v7/pkg/modules/api"
+	flag "github.com/spf13/pflag"
+)
+
+func init() {
+	gotenberg.MustRegisterModule(PDFEngines{})
+}
+
+// PDFEngines is a module which gathers available gotenberg.PDFEngine modules.
+// The available gotenberg.PDFEngine modules can be either all
+// gotenberg.PDFEngine modules or the modules selected by the user thanks to
+// the "engines" flag.
+//
+// PDFEngines wraps the gotenberg.PDFEngine modules in an internal struct which
+// also implements gotenberg.PDFEngine. This struct provides a sort of fallback
+// mechanism: if an engine's method returns an error, it calls the same method
+// from another engine.
+//
+// This module implements the gotenberg.PDFEngineProvider interface.
+type PDFEngines struct {
+	names         []string
+	engines       []gotenberg.PDFEngine
+	disableRoutes bool
+}
+
+// Descriptor returns a PDFEngines' module descriptor.
+func (PDFEngines) Descriptor() gotenberg.ModuleDescriptor {
+	return gotenberg.ModuleDescriptor{
+		ID: "pdfengines",
+		FlagSet: func() *flag.FlagSet {
+			fs := flag.NewFlagSet("pdfengines", flag.ExitOnError)
+			fs.StringSlice("pdfengines-engines", make([]string, 0), "Set the PDF engines - all by default")
+			fs.Bool("pdfengines-disable-routes", false, "Disable the routes")
+
+			return fs
+		}(),
+		New: func() gotenberg.Module { return new(PDFEngines) },
+	}
+}
+
+// Provision gets either all gotenberg.PDFEngine modules or the modules
+// selected by the user thanks to the "engines" flag.
+func (mod *PDFEngines) Provision(ctx *gotenberg.Context) error {
+	flags := ctx.ParsedFlags()
+	names := flags.MustStringSlice("pdfengines-engines")
+	mod.disableRoutes = flags.MustBool("pdfengines-disable-routes")
+
+	engines, err := ctx.Modules(new(gotenberg.PDFEngine))
+	if err != nil {
+		return fmt.Errorf("get PDF engines: %w", err)
+	}
+
+	mod.engines = make([]gotenberg.PDFEngine, len(engines))
+
+	for i, engine := range engines {
+		mod.engines[i] = engine.(gotenberg.PDFEngine)
+	}
+
+	if len(names) > 0 {
+		// Selection from user.
+		mod.names = names
+
+		return nil
+	}
+
+	// No selection from user, use all PDF engines available.
+	mod.names = make([]string, len(mod.engines))
+
+	for i, engine := range mod.engines {
+		mod.names[i] = engine.(gotenberg.Module).Descriptor().ID
+	}
+
+	return nil
+}
+
+// Validate validates there is at least one gotenberg.PDFEngine module
+// available. It also validates that selected gotenberg.PDFEngine modules
+// actually exist.
+func (mod PDFEngines) Validate() error {
+	if len(mod.engines) == 0 {
+		return errors.New("no PDF engine")
+	}
+
+	availableEngines := make([]string, len(mod.engines))
+
+	for i, engine := range mod.engines {
+		availableEngines[i] = engine.(gotenberg.Module).Descriptor().ID
+	}
+
+	nonExistingEngines := make([]string, 0)
+
+	for _, name := range mod.names {
+		engineExists := false
+
+		for _, engine := range mod.engines {
+			if name == engine.(gotenberg.Module).Descriptor().ID {
+				engineExists = true
+				break
+			}
+		}
+
+		if !engineExists {
+			nonExistingEngines = append(nonExistingEngines, name)
+		}
+	}
+
+	if len(nonExistingEngines) == 0 {
+		return nil
+	}
+
+	return fmt.Errorf("non-existing PDF engine(s): %s - available PDF engine(s): %s", nonExistingEngines, availableEngines)
+}
+
+// PDFEngine returns a gotenberg.PDFEngine.
+func (mod PDFEngines) PDFEngine() (gotenberg.PDFEngine, error) {
+	engines := make([]gotenberg.PDFEngine, len(mod.engines))
+
+	i := 0
+	for _, engine := range mod.engines {
+		engines[i] = engine
+		i++
+	}
+
+	return newMultiPDFEngines(engines...), nil
+}
+
+// Routes returns the API routes.
+func (mod PDFEngines) Routes() ([]api.MultipartFormDataRoute, error) {
+	if mod.disableRoutes {
+		return nil, nil
+	}
+
+	engine, err := mod.PDFEngine()
+	if err != nil {
+		// Should not happen, unless our provider implementation
+		// changes in the future.
+		return nil, fmt.Errorf("get pdf engine: %w", err)
+	}
+
+	return []api.MultipartFormDataRoute{
+		mergeRoute(engine),
+		convertRoute(engine),
+	}, nil
+}
+
+// Interface guards.
+var (
+	_ gotenberg.Module            = (*PDFEngines)(nil)
+	_ gotenberg.Provisioner       = (*PDFEngines)(nil)
+	_ gotenberg.Validator         = (*PDFEngines)(nil)
+	_ gotenberg.PDFEngineProvider = (*PDFEngines)(nil)
+	_ api.MultipartFormDataRouter = (*PDFEngines)(nil)
+)