huge refactoring

internal/app/xhttp/pkg/context/context.go

@@ -0,0 +1,210 @@
+package context
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/labstack/echo/v4"
+	"github.com/thecodingmachine/gotenberg/internal/app/xhttp/pkg/resource"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/conf"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/pm2"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xerror"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xlog"
+)
+
+// Context extends the default echo.Context.
+type Context struct {
+	echo.Context
+	logger    xlog.Logger
+	config    conf.Config
+	processes []pm2.Process
+	resource  resource.Resource
+	startTime time.Time
+}
+
+// New creates a new Context.
+func New(c echo.Context, logger xlog.Logger, config conf.Config, processess ...pm2.Process) Context {
+	return Context{
+		c,
+		logger,
+		config,
+		processess,
+		resource.Resource{},
+		time.Now(),
+	}
+}
+
+/*
+MustCastFromEchoContext cast an echo.Context
+to our custom Context.
+
+It panics if casting goes wrong.
+*/
+func MustCastFromEchoContext(c echo.Context) Context {
+	const op string = "context.MustCastFromEchoContext"
+	ctx, ok := c.(Context)
+	if !ok {
+		panic(fmt.Sprintf("%s: unable to cast an echo.Context to our custom context.Context", op))
+	}
+	return ctx
+}
+
+/*
+XLogger returns the xlog.Logger associated
+with the Context.
+
+This method should be used instead of the
+default Logger() method coming from
+the echo.Context.
+*/
+func (ctx Context) XLogger() xlog.Logger {
+	return ctx.logger
+}
+
+// Config returns the conf.Config associated
+// with the Context.
+func (ctx Context) Config() conf.Config {
+	return ctx.config
+}
+
+// ProcessesHealthcheck returns an error if
+// one of the processes is not viable.
+func (ctx Context) ProcessesHealthcheck() error {
+	const op string = "context.Context.ProcessesHealthcheck"
+	for _, process := range ctx.processes {
+		if !process.IsViable() {
+			return xerror.New(
+				op,
+				fmt.Errorf("'%s' is not viable", process.Fullname()),
+			)
+		}
+	}
+	return nil
+}
+
+// WithResource creates a resource.Resource and
+// adds it to the Context.
+func (ctx *Context) WithResource(directoryName string) error {
+	const op string = "context.Context.WithResource"
+	resolver := func() (resource.Resource, error) {
+		r, err := resource.New(ctx.logger, directoryName)
+		if err != nil {
+			return r, err
+		}
+		// retrieve form values from request.
+		for _, key := range resource.ArgKeys() {
+			r.WithArg(key, ctx.FormValue(string(key)))
+		}
+		// write form files from request.
+		form, err := ctx.MultipartForm()
+		if err != nil {
+			return r, err
+		}
+		for _, files := range form.File {
+			for _, fh := range files {
+				in, err := fh.Open()
+				if err != nil {
+					return r, err
+				}
+				defer in.Close() // nolint: errcheck
+				if err := r.WithFile(fh.Filename, in); err != nil {
+					return r, err
+				}
+			}
+		}
+		return r, nil
+	}
+	resource, err := resolver()
+	ctx.resource = resource
+	if err != nil {
+		return xerror.New(op, err)
+	}
+	return nil
+}
+
+/*
+MustResource returns the resource.Resource
+associated with the Context.
+
+It panics if no resource.Resource.
+*/
+func (ctx Context) MustResource() resource.Resource {
+	const op string = "context.Context.MustResource"
+	if !ctx.HasResource() {
+		panic(fmt.Sprintf("%s: unable to retrieve the resource.Resource from our custom context.Context", op))
+	}
+	return ctx.resource
+}
+
+// HasResource returns true if the Context
+// has a resource.Resource.
+func (ctx Context) HasResource() bool {
+	return &ctx.resource != nil
+}
+
+/*
+LogRequestResult logs the result of a request.
+This method should only be used by a middleware!
+
+If an error is given, returns the exact same error.
+*/
+func (ctx Context) LogRequestResult(err error, isDebug bool) error {
+	const op string = "context.Context.LogRequestResult"
+	req := ctx.Request()
+	resp := ctx.Response()
+	stopTime := time.Now()
+	fields := map[string]interface{}{
+		"remote_ip":     ctx.RealIP(),
+		"host":          req.Host,
+		"uri":           req.RequestURI,
+		"method":        req.Method,
+		"path":          path(req),
+		"referer":       req.Referer(),
+		"user_agent":    req.UserAgent(),
+		"status":        resp.Status,
+		"latency":       lantency(ctx.startTime, stopTime),
+		"latency_human": latencyHuman(ctx.startTime, stopTime),
+		"bytes_in":      bytesIn(req),
+		"bytes_out":     bytesOut(resp),
+	}
+	if err != nil {
+		ctx.logger.WithFields(fields).ErrorfOp(op, "request failed")
+		return err
+	}
+	if isDebug {
+		ctx.logger.WithFields(fields).DebugfOp(op, "request handled")
+		return nil
+	}
+	ctx.logger.WithFields(fields).InfofOp(op, "request handled")
+	return nil
+}
+
+func path(r *http.Request) string {
+	path := r.URL.Path
+	if path == "" {
+		path = "/"
+	}
+	return path
+}
+
+func lantency(startTime time.Time, stopTime time.Time) string {
+	return strconv.FormatInt(int64(stopTime.Sub(startTime)), 10)
+}
+
+func latencyHuman(startTime time.Time, stopTime time.Time) string {
+	return stopTime.Sub(startTime).String()
+}
+
+func bytesIn(r *http.Request) string {
+	bytesIn := r.Header.Get(echo.HeaderContentLength)
+	if bytesIn == "" {
+		bytesIn = "0"
+	}
+	return bytesIn
+}
+
+func bytesOut(r *echo.Response) string {
+	return strconv.FormatInt(r.Size, 10)
+}