feat: GET /article endpoint proxies Wikimedia structured contents

GET /article?username=alice&name=en.wikipedia/Sun
→ proxies to api.enterprise.wikimedia.com/v2/structured-contents/{name}
with Authorization: Bearer <access_token>

Returns 401 for unknown users, 400 if params missing,
and passes through the upstream HTTP status on errors.

2 files changed, 50 insertions, 0 deletions

diff --git a/api/handlers.go b/api/handlers.go
index 0f3b48b..6813dc2 100644
--- a/api/handlers.go
+++ b/api/handlers.go
@@ -2,11 +2,13 @@ package api
 
 import (
 	"context"
+	"io"
 	"database/sql"
 	"errors"
 	"encoding/json"
 	"log"
 	"net/http"
+	"net/url"
 	"time"
 
 	"wikiapiserver/db"
@@ -202,3 +204,50 @@ func (h *Handler) GetToken(w http.ResponseWriter, r *http.Request) {
 		ValidUntil:  acct.AccessTokenExpiry.Add(24 * time.Hour).Format(time.RFC3339),
 	})
 }
+// --- Get Article: GET /article?username=...&name=... ---
+
+func (h *Handler) GetArticle(w http.ResponseWriter, r *http.Request) {
+	ctx, cancel := context.WithTimeout(r.Context(), 30*time.Second)
+	defer cancel()
+
+	username := r.URL.Query().Get("username")
+	article := r.URL.Query().Get("name")
+	if username == "" || article == "" {
+		badRequest(w, "username and name query parameters are required")
+		return
+	}
+
+	acct, err := h.db.GetAccount(ctx, username)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			unauthorized(w)
+			return
+		}
+		serverError(w, "could not retrieve token")
+		return
+	}
+
+	url := "https://api.enterprise.wikimedia.com/v2/structured-contents/" + url.QueryEscape(article)
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		serverError(w, "could not build request")
+		return
+	}
+	req.Header.Set("Authorization", "Bearer "+acct.AccessToken)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		serverError(w, "wikimedia api error")
+		return
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		b, _ := io.ReadAll(resp.Body)
+		http.Error(w, string(b), resp.StatusCode)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	io.Copy(w, resp.Body) //nolint:errcheck
+}
diff --git a/main.go b/main.go
index f2cf44d..341a175 100644
--- a/main.go
+++ b/main.go
@@ -87,6 +87,7 @@ func main() {
 	mux.HandleFunc("POST /refresh", handler.Refresh)
 	mux.HandleFunc("GET /health", handler.Health)
 	mux.HandleFunc("GET /token", handler.GetToken)
+	mux.HandleFunc("GET /article", handler.GetArticle)
 
 	addr := fmt.Sprintf(":%d", cfg.Server.Port)
 	srv := &http.Server{