feat: pubsub router

q/pubsub-router/router.go

@@ -0,0 +1,65 @@
+package pubsubrouter
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+	"github.com/glocurrency/commons/instrumentation"
+	"github.com/glocurrency/commons/q"
+)
+
+type router struct {
+	*gin.Engine
+	prefix string
+}
+
+func NewRouter(engine *gin.Engine, prefix string) *router {
+	return &router{Engine: engine, prefix: prefix}
+}
+
+func (r *router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if strings.Contains(req.URL.Path, r.prefix) {
+		if err := RewriteForPubSub(req); err != nil {
+			instrumentation.NoticeError(context.Background(), err, "cannot rewrite",
+				instrumentation.WithField("prefix", r.prefix))
+		}
+	}
+	r.Engine.ServeHTTP(w, req)
+}
+
+func RewriteForPubSub(req *http.Request) error {
+	data, err := io.ReadAll(req.Body)
+	if err != nil {
+		return fmt.Errorf("cannot read body: %w", err)
+	}
+
+	req.Body = io.NopCloser(bytes.NewBuffer(data))
+
+	var msg q.PubSubMessage
+	if err := json.Unmarshal(data, &msg); err != nil {
+		return fmt.Errorf("cannot unmarshal '%s': %w", string(data), err)
+	}
+
+	name := msg.GetName()
+	if name == "" {
+		return nil
+	}
+
+	parsedURI, err := url.ParseRequestURI(req.RequestURI)
+	if err != nil {
+		return fmt.Errorf("cannot parse uri '%s': %w", req.RequestURI, err)
+	}
+
+	parsedURI.Path = strings.TrimRight(parsedURI.Path, "/") + "/" + name
+	req.RequestURI = parsedURI.String()
+
+	req.URL.Path = strings.TrimRight(req.URL.Path, "/") + "/" + name
+	return nil
+}

q/pubsub-router/router_test.go

@@ -0,0 +1,68 @@
+package pubsubrouter_test
+
+import (
+	"bytes"
+	_ "embed"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	pubsubrouter "github.com/glocurrency/commons/q/pubsub-router"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMain(m *testing.M) {
+	gin.SetMode(gin.ReleaseMode)
+	os.Exit(m.Run())
+}
+
+//go:embed testdata/with-name-d.json
+var withNameD []byte
+
+//go:embed testdata/with-name-e.json
+var withNameE []byte
+
+//go:embed testdata/with-name-def.json
+var withNameDEF []byte
+
+func TestRouting(t *testing.T) {
+	tests := []struct {
+		name       string
+		url        string
+		body       []byte
+		wantStatus int
+	}{
+		{"pubsub not found", "/abc", nil, http.StatusNotFound},
+		{"pubsub not found, name do not match route", "/abc", withNameE, http.StatusNotFound},
+		{"pubsub routed", "/abc", withNameD, http.StatusAccepted},
+		{"pubsub routed", "/abc?a=b", withNameD, http.StatusAccepted},
+		{"pubsub routed", "/abc/", withNameD, http.StatusAccepted},
+		{"pubsub routed", "/abc/?a=b", withNameD, http.StatusAccepted},
+		{"pubsub routed", "/abc", withNameDEF, http.StatusAccepted},
+		{"not pubpub", "/123/4", withNameD, http.StatusOK},
+	}
+
+	for i := range tests {
+		test := tests[i]
+		t.Run(test.name, func(t *testing.T) {
+			t.Parallel()
+
+			w := httptest.NewRecorder()
+			req := httptest.NewRequest(http.MethodPost, test.url, bytes.NewReader(test.body))
+
+			router := pubsubrouter.NewRouter(gin.New(), "/abc")
+
+			group1 := router.Group("/abc")
+			group1.POST("d", func(ctx *gin.Context) { ctx.Status(http.StatusAccepted) })
+			group1.POST("d-e-f", func(ctx *gin.Context) { ctx.Status(http.StatusAccepted) })
+
+			group2 := router.Group("/123")
+			group2.POST("4", func(ctx *gin.Context) { ctx.Status(http.StatusOK) })
+
+			router.ServeHTTP(w, req)
+			assert.Equal(t, test.wantStatus, w.Code)
+		})
+	}
+}

q/pubsub-router/testdata/with-name-d.json

@@ -0,0 +1,10 @@
+{
+    "message": {
+        "messageId": "158b5c5d-ce6b-4020-b822-ceb0e43b754a",
+        "publishTime": "2023-07-09T17:49:48.087822341Z",
+        "attributes": {
+            "nameKey": "d"
+        }
+    },
+    "subscription": "sub-123"
+}

q/pubsub-router/testdata/with-name-def.json

@@ -0,0 +1,10 @@
+{
+    "message": {
+        "messageId": "158b5c5d-ce6b-4020-b822-ceb0e43b754a",
+        "publishTime": "2023-07-09T17:49:48.087822341Z",
+        "attributes": {
+            "nameKey": "d-e-f"
+        }
+    },
+    "subscription": "sub-123"
+}

q/pubsub-router/testdata/with-name-e.json

@@ -0,0 +1,10 @@
+{
+    "message": {
+        "messageId": "158b5c5d-ce6b-4020-b822-ceb0e43b754a",
+        "publishTime": "2023-07-09T17:49:48.087822341Z",
+        "attributes": {
+            "nameKey": "e"
+        }
+    },
+    "subscription": "sub-123"
+}