Merge pull request #18 from participating-online/15-add-createeditdel…

…ete-post-handling

Add initial activity routes

.codesandbox/tasks.json

@@ -16,6 +16,16 @@
         "branch": true,
         "resume": true
       }
+    },
+    "go test": {
+      "name": "Test",
+      "command": "go test -v ./...",
+      "runAtStart": true,
+      "restartOn": {
+        "files": ["*"],
+        "branch": true,
+        "resume": true
+      }
     }
   }
 }

CONTRIBUTING.md

@@ -0,0 +1,16 @@
+# Contributing
+Aka. Developer Guidelines
+
+## Intro
+
+We're currently _very_ early in the development stages of the Sublinks federation service. Therefore there aren't too many guidelines yet. However, as you can see below there are some that we would appreciate you to consider before and while you contribute to this project.
+
+As with most things you'll read about in this document, even these guidelines are up for discussion. If you believe anything should be changed please feel free to create a pull request and let us know what and why. Same thing applies if you want to add or stricten/loosen a guideline.
+
+## Tests
+
+Support for tests has been set up. Please submit unit and/or end-to-end tests with all PRs. 100% coverage (at least with unit tests) is a falacy. Ideally we want to strive for "good enough" coverage instead.
+
+## Pull Requests
+
+The pull request flow in this project isn't anything special. We require a pull request to be created before anything is merged into `main`. At least one person must approve the pull request.

go.mod

@@ -2,4 +2,7 @@ module participating-online/sublinks-federation
 
 go 1.21.4
 
-require github.com/gorilla/mux v1.8.1
+require (
+	github.com/gorilla/mux v1.8.1
+	golang.org/x/text v0.14.0
+)

go.sum

@@ -1,2 +1,4 @@
 github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
 github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=

internal/activitypub/activity.go

@@ -0,0 +1,33 @@
+package activitypub
+
+type Activity struct {
+	Context  Context     `json:"@context"`
+	Actor    string      `json:"actor"`
+	To       []string    `json:"to"`
+	Object   interface{} `json:"object"`
+	Cc       []string    `json:"cc"`
+	Audience string      `json:"audience"`
+	Type     string      `json:"type"`
+	Id       string      `json:"id"`
+}
+
+func NewActivity(
+	id string,
+	actType string,
+	actor string,
+	to []string,
+	cc []string,
+	audience string,
+	obj interface{},
+) Activity {
+	return Activity{
+		Context:  *GetContext(),
+		Id:       id,
+		Type:     actType,
+		Actor:    actor,
+		To:       to,
+		Cc:       cc,
+		Audience: audience,
+		Object:   obj,
+	}
+}

internal/activitypub/context.go

@@ -26,8 +26,8 @@ type moderator struct {
 	Id   string `json:"@id"`
 }
 
-func GetContext() Context {
-	return Context{
+func GetContext() *Context {
+	return &Context{
 		"https://www.w3.org/ns/activitystreams",
 		"https://w3id.org/security/v1",
 		lemmyContextData{

internal/activitypub/post.go

@@ -12,28 +12,27 @@ type Language struct {
 }
 
 type Post struct {
-	Context         Context   `json:"@context"`
+	Context         *Context  `json:"@context,omitempty"`
 	Id              string    `json:"id"`
 	Type            string    `json:"type"`
 	AttributedTo    string    `json:"attributedTo"`
 	To              []string  `json:"to"`
-	Cc              []string  `json:"cc"`
+	Cc              []string  `json:"cc,omitempty"`
 	Audience        string    `json:"audience"`
 	Name            string    `json:"name"`
 	Content         string    `json:"content"`
 	MediaType       string    `json:"mediaType"`
 	Source          Source    `json:"source"`
-	Attachment      []Link    `json:"attachment"`
-	Image           []Link    `json:"image"`
+	Attachment      []Link    `json:"attachment,omitempty"`
+	Image           []Link    `json:"image,omitempty"`
 	Sensitive       bool      `json:"sensitive"`
 	CommentsEnabled bool      `json:"commentsEnabled"`
 	Language        Language  `json:"language"`
 	Published       time.Time `json:"published"`
 }
 
-func NewPost(postUrl string, fromUser string, communityUrl string, postTitle string, postBody string, nsfw bool, published time.Time) Post {
-	post := Post{
-		Context:      GetContext(),
+func NewPost(postUrl string, fromUser string, communityUrl string, postTitle string, postBody string, nsfw bool, published time.Time) *Post {
+	return &Post{
 		Id:           postUrl,
 		Type:         "Page",
 		AttributedTo: fromUser,
@@ -57,10 +56,9 @@ func NewPost(postUrl string, fromUser string, communityUrl string, postTitle str
 		},
 		Published: published,
 	}
-	return post
 }
 
-func ConvertPostToApub(p *lemmy.PostResponse) Post {
+func ConvertPostToApub(p *lemmy.PostResponse) *Post {
 	return NewPost(
 		p.PostView.Post.ApId,
 		fmt.Sprintf("https://demo.sublinks.org/u/%s", p.PostView.Creator.Name),

internal/activitypub/user.go

@@ -17,7 +17,7 @@ type Endpoints struct {
 }
 
 type User struct {
-	Context           Context   `json:"@context"`
+	Context           *Context  `json:"@context"`
 	Id                string    `json:"id"`
 	PreferredUsername string    `json:"preferredUsername"`
 	Inbox             string    `json:"inbox"`

internal/http/routes/activity.go

@@ -0,0 +1,66 @@
+package routes
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+	"net/http"
+	"participating-online/sublinks-federation/internal/activitypub"
+	"participating-online/sublinks-federation/internal/lemmy"
+
+	"fmt"
+
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
+
+	"github.com/gorilla/mux"
+)
+
+func SetupActivityRoutes(r *mux.Router) {
+	r.HandleFunc("/activities/{action}/{id}", getActivityHandler).Methods("GET")
+}
+
+func getActivityHandler(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+	var content []byte
+	switch vars["action"] {
+	case "create":
+		obj, err := GetPostActivityObject(vars["id"])
+		if err != nil {
+			log.Println("Error reading object", err)
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+		content, _ = json.MarshalIndent(
+			activitypub.NewActivity(
+				r.RequestURI,
+				cases.Title(language.English).String(vars["action"]),
+				obj.AttributedTo,
+				obj.To,
+				obj.Cc,
+				obj.Audience,
+				obj,
+			), "", "  ")
+
+		break
+	default:
+		error.Error(fmt.Errorf("action %s not found", vars["action"]))
+		w.WriteHeader(http.StatusNotFound)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+	w.Header().Add("content-type", "application/activity+json")
+	w.Write(content)
+}
+
+func GetPostActivityObject(id string) (*activitypub.Post, error) {
+	ctx := context.Background()
+	c := lemmy.GetLemmyClient(ctx)
+	post, err := c.GetPost(ctx, id)
+	if err != nil {
+		log.Println("Error reading post", err)
+		return nil, err
+	}
+	return activitypub.ConvertPostToApub(post), nil
+}

internal/http/routes/post.go

@@ -25,6 +25,7 @@ func getPostHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	postLd := activitypub.ConvertPostToApub(post)
+	postLd.Context = activitypub.GetContext()
 	w.WriteHeader(http.StatusOK)
 	w.Header().Add("content-type", "application/activity+json")
 	content, _ := json.MarshalIndent(postLd, "", "  ")

internal/http/routes/routes.go

@@ -7,5 +7,6 @@ func SetupRoutes() *mux.Router {
 	SetupUserRoutes(r)
 	SetupPostRoutes(r)
 	SetupApubRoutes(r)
+	SetupActivityRoutes(r)
 	return r
 }