v3.0.0 (#18)

internal/app/api/api.go

@@ -0,0 +1,125 @@
+package api
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"os"
+	"os/signal"
+	"time"
+
+	"github.com/labstack/echo"
+	"github.com/labstack/echo/middleware"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/notify"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/pm2"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/printer"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/rand"
+)
+
+// Start starts the API server on port 3000.
+func Start() error {
+	e := setup()
+	// start Chrome headless and
+	// unoconv listener with PM2.
+	chrome := &pm2.Chrome{}
+	unoconv := &pm2.Unoconv{}
+	if err := chrome.Launch(); err != nil {
+		return err
+	}
+	if err := unoconv.Launch(); err != nil {
+		return err
+	}
+	// run our API in a goroutine so that it doesn't block.
+	go func() {
+		notify.Println("http server started on port 3000")
+		if err := e.Start(":3000"); err != nil {
+			e.Logger.Fatalf("%v", err)
+			os.Exit(1)
+		}
+	}()
+	quit := make(chan os.Signal, 1)
+	// we'll accept graceful shutdowns when quit via SIGINT (Ctrl+C)
+	// SIGKILL, SIGQUIT or SIGTERM (Ctrl+/) will not be caught.
+	signal.Notify(quit, os.Interrupt)
+	// block until we receive our signal.
+	<-quit
+	// create a deadline to wait for.
+	ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
+	defer cancel()
+	// doesn't block if no connections, but will otherwise wait
+	// until the timeout deadline.
+	notify.Println("shutting down http server... (Ctrl+C to force)")
+	return e.Shutdown(ctx)
+}
+
+func setup() *echo.Echo {
+	e := echo.New()
+	e.HideBanner = true
+	e.HidePort = true
+	e.Use(middleware.Logger())
+	e.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			if err := next(c); err != nil {
+				// TODO should return a better HTTP status code
+				// than 500 for some cases.
+				return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("%v", err))
+			}
+			return nil
+		}
+	})
+	e.POST("/merge", merge)
+	g := e.Group("/convert")
+	g.POST("/html", convertHTML)
+	g.POST("/markdown", convertMarkdown)
+	g.POST("/office", convertOffice)
+	return e
+}
+
+func newContext(r *resource) (context.Context, context.CancelFunc) {
+	webhookURL := r.webhookURL()
+	if webhookURL == "" {
+		ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
+		return ctx, cancel
+	}
+	return context.Background(), nil
+}
+
+func print(c echo.Context, p printer.Printer, r *resource) error {
+	baseFilename, err := rand.Get()
+	if err != nil {
+		return fmt.Errorf("getting result file name: %v", err)
+	}
+	filename := fmt.Sprintf("%s.pdf", baseFilename)
+	fpath := fmt.Sprintf("%s/%s", r.dirPath, filename)
+	if r.webhookURL() == "" {
+		// if no webhook URL given, run conversion
+		// and directly return the resulting PDF file
+		// or and error.
+		if err := p.Print(fpath); err != nil {
+			return err
+		}
+		return c.Attachment(fpath, filename)
+	}
+	// as a webhook URL has been given, we
+	// run the following lines in a goroutine so that
+	// it doesn't block.
+	go func() {
+		if err := p.Print(fpath); err != nil {
+			c.Logger().Errorf("%v", err)
+			return
+		}
+		f, err := os.Open(fpath)
+		if err != nil {
+			c.Logger().Errorf("%v", err)
+			return
+		}
+		defer f.Close()
+		resp, err := http.Post(r.webhookURL(), "application/pdf", f)
+		if err != nil {
+			c.Logger().Errorf("%v", err)
+			return
+		}
+		defer resp.Body.Close()
+	}()
+	return nil
+}