reimplement v2 API controller

internal/web/response_writer.go

@@ -0,0 +1,33 @@
+package web
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+func writeErr(writer http.ResponseWriter, err error) {
+	writeString(writer, http.StatusInternalServerError, err.Error())
+}
+
+func writeString(writer http.ResponseWriter, status int, value string) {
+	writer.WriteHeader(status)
+	writer.Write([]byte(value))
+}
+
+func writeJSON(writer http.ResponseWriter, status int, value any) error {
+	jsonData, err := json.Marshal(value)
+	if err != nil {
+		return err
+	}
+
+	writer.WriteHeader(status)
+	writer.Write(jsonData)
+
+	return nil
+}
+
+func writeJSONOrErr(writer http.ResponseWriter, status int, value any) {
+	if err := writeJSON(writer, status, value); err != nil {
+		writeErr(writer, err)
+	}
+}

internal/web/server.go

@@ -0,0 +1,49 @@
+package web
+
+import (
+	"github.com/go-chi/chi/v5"
+	"github.com/lus/pasty/internal/storage"
+	"net/http"
+)
+
+type Server struct {
+	// The address the web server should listen to.
+	Address string
+
+	// The storage driver to use.
+	Storage storage.Driver
+
+	// Whether the Hastebin support should be enabled.
+	// If this is set to 'false', the Hastebin specific endpoints will not be registered.
+	HastebinSupport bool
+
+	// The length of newly generated paste IDs.
+	PasteIDLength int
+	// The charset to use when generating new paste IDs.
+	PasteIDCharset string
+
+	// The maximum length of newly generated pastes.
+	PasteLengthCap int
+
+	// Whether modification tokens are enabled.
+	ModificationTokensEnabled bool
+	// The length of newly generated modification tokens.
+	ModificationTokenLength int
+	// The charset to use when generating new modification tokens.
+	ModificationTokenCharset string
+
+	// The administration tokens.
+	AdminTokens []string
+}
+
+func (server *Server) Start() error {
+	router := chi.NewRouter()
+
+	// Register the paste API endpoints
+	router.With(server.v2MiddlewareInjectPaste).Get("/api/v2/pastes/{paste_id}", server.v2EndpointGetPaste)
+	router.Post("/api/v2/pastes", server.v2EndpointCreatePaste)
+	router.With(server.v2MiddlewareInjectPaste, server.v2MiddlewareAuthorize).Patch("/api/v2/pastes/{paste_id}", server.v2EndpointModifyPaste)
+	router.Delete("/api/v2/pastes/{paste_id}", server.v2EndpointDeletePaste)
+
+	return http.ListenAndServe(server.Address, router)
+}

internal/web/v2_end_create_paste.go

@@ -0,0 +1,70 @@
+package web
+
+import (
+	"encoding/json"
+	"github.com/lus/pasty/internal/pastes"
+	"github.com/lus/pasty/internal/randx"
+	"io"
+	"net/http"
+	"time"
+)
+
+type v2EndpointCreatePastePayload struct {
+	Content  string         `json:"content"`
+	Metadata map[string]any `json:"metadata"`
+}
+
+func (server *Server) v2EndpointCreatePaste(writer http.ResponseWriter, request *http.Request) {
+	// Read, parse and validate the request payload
+	body, err := io.ReadAll(request.Body)
+	if err != nil {
+		writeErr(writer, err)
+		return
+	}
+	payload := new(v2EndpointCreatePastePayload)
+	if err := json.Unmarshal(body, payload); err != nil {
+		writeErr(writer, err)
+		return
+	}
+	if payload.Content == "" {
+		writeString(writer, http.StatusBadRequest, "missing paste content")
+		return
+	}
+	if server.PasteLengthCap > 0 && len(payload.Content) > server.PasteLengthCap {
+		writeString(writer, http.StatusBadRequest, "too large paste content")
+		return
+	}
+
+	id, err := pastes.GenerateID(request.Context(), server.Storage.Pastes(), server.PasteIDCharset, server.PasteIDLength)
+	if err != nil {
+		writeErr(writer, err)
+		return
+	}
+
+	paste := &pastes.Paste{
+		ID:       id,
+		Content:  payload.Content,
+		Created:  time.Now().Unix(),
+		Metadata: payload.Metadata,
+	}
+
+	modificationToken := ""
+	if server.ModificationTokensEnabled {
+		modificationToken = randx.String(server.ModificationTokenCharset, server.ModificationTokenLength)
+		paste.ModificationToken = modificationToken
+
+		if err := paste.HashModificationToken(); err != nil {
+			writeErr(writer, err)
+			return
+		}
+	}
+
+	if err := server.Storage.Pastes().Upsert(request.Context(), paste); err != nil {
+		writeErr(writer, err)
+		return
+	}
+
+	cpy := *paste
+	cpy.ModificationToken = modificationToken
+	writeJSONOrErr(writer, http.StatusCreated, cpy)
+}

internal/web/v2_end_delete_paste.go

@@ -0,0 +1,18 @@
+package web
+
+import (
+	"github.com/lus/pasty/internal/pastes"
+	"net/http"
+)
+
+func (server *Server) v2EndpointDeletePaste(writer http.ResponseWriter, request *http.Request) {
+	paste, ok := request.Context().Value("paste").(*pastes.Paste)
+	if !ok {
+		writeString(writer, http.StatusInternalServerError, "missing paste object")
+		return
+	}
+
+	if err := server.Storage.Pastes().DeleteByID(request.Context(), paste.ID); err != nil {
+		writeErr(writer, err)
+	}
+}

internal/web/v2_end_get_paste.go

@@ -0,0 +1,18 @@
+package web
+
+import (
+	"github.com/lus/pasty/internal/pastes"
+	"net/http"
+)
+
+func (server *Server) v2EndpointGetPaste(writer http.ResponseWriter, request *http.Request) {
+	paste, ok := request.Context().Value("paste").(*pastes.Paste)
+	if !ok {
+		writeString(writer, http.StatusInternalServerError, "missing paste object")
+		return
+	}
+
+	cpy := *paste
+	cpy.ModificationToken = ""
+	writeJSONOrErr(writer, http.StatusOK, cpy)
+}

internal/web/v2_end_modify_paste.go

@@ -0,0 +1,60 @@
+package web
+
+import (
+	"encoding/json"
+	"github.com/lus/pasty/internal/pastes"
+	"io"
+	"net/http"
+)
+
+type v2EndpointModifyPastePayload struct {
+	Content  *string        `json:"content"`
+	Metadata map[string]any `json:"metadata"`
+}
+
+func (server *Server) v2EndpointModifyPaste(writer http.ResponseWriter, request *http.Request) {
+	paste, ok := request.Context().Value("paste").(*pastes.Paste)
+	if !ok {
+		writeString(writer, http.StatusInternalServerError, "missing paste object")
+		return
+	}
+
+	// Read, parse and validate the request payload
+	body, err := io.ReadAll(request.Body)
+	if err != nil {
+		writeErr(writer, err)
+		return
+	}
+	payload := new(v2EndpointModifyPastePayload)
+	if err := json.Unmarshal(body, payload); err != nil {
+		writeErr(writer, err)
+		return
+	}
+	if payload.Content != nil && *payload.Content == "" {
+		writeString(writer, http.StatusBadRequest, "missing paste content")
+		return
+	}
+	if payload.Content != nil && server.PasteLengthCap > 0 && len(*payload.Content) > server.PasteLengthCap {
+		writeString(writer, http.StatusBadRequest, "too large paste content")
+		return
+	}
+
+	// Modify the paste itself
+	if payload.Content != nil {
+		paste.Content = *payload.Content
+	}
+	if payload.Metadata != nil {
+		for key, value := range payload.Metadata {
+			if value == nil {
+				delete(paste.Metadata, key)
+				continue
+			}
+			paste.Metadata[key] = value
+		}
+	}
+
+	// Save the modified paste
+	if err := server.Storage.Pastes().Upsert(request.Context(), paste); err != nil {
+		writeErr(writer, err)
+	}
+}

internal/web/v2_mid_authorize.go

@@ -0,0 +1,37 @@
+package web
+
+import (
+	"github.com/lus/pasty/internal/pastes"
+	"github.com/lus/pasty/internal/slices"
+	"net/http"
+	"strings"
+)
+
+func (server *Server) v2MiddlewareAuthorize(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+		paste, ok := request.Context().Value("paste").(*pastes.Paste)
+		if !ok {
+			writeString(writer, http.StatusInternalServerError, "missing paste object")
+			return
+		}
+
+		authHeader := strings.SplitN(request.Header.Get("Authorization"), " ", 2)
+		if len(authHeader) != 2 || authHeader[0] != "Bearer" {
+			writeString(writer, http.StatusUnauthorized, "unauthorized")
+			return
+		}
+
+		isAdmin := slices.Contains(server.AdminTokens, authHeader[1])
+		if isAdmin {
+			next.ServeHTTP(writer, request)
+			return
+		}
+
+		if !server.ModificationTokensEnabled || !paste.CheckModificationToken(authHeader[1]) {
+			writeString(writer, http.StatusUnauthorized, "unauthorized")
+			return
+		}
+
+		next.ServeHTTP(writer, request)
+	})
+}

internal/web/v2_mid_inject_paste.go

@@ -0,0 +1,38 @@
+package web
+
+import (
+	"context"
+	"github.com/go-chi/chi/v5"
+	"net/http"
+	"strings"
+)
+
+func (server *Server) v2MiddlewareInjectPaste(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+		pasteID := strings.TrimSpace(chi.URLParam(request, "paste_id"))
+		if pasteID == "" {
+			writeString(writer, http.StatusNotFound, "paste not found")
+			return
+		}
+
+		paste, err := server.Storage.Pastes().FindByID(request.Context(), pasteID)
+		if err != nil {
+			if pasteID == "" {
+				writeErr(writer, err)
+				return
+			}
+		}
+		if paste == nil {
+			writeString(writer, http.StatusNotFound, "paste not found")
+			return
+		}
+
+		if paste.Metadata == nil {
+			paste.Metadata = make(map[string]any)
+		}
+
+		request = request.WithContext(context.WithValue(request.Context(), "paste", paste))
+
+		next.ServeHTTP(writer, request)
+	})
+}