at-container-registry/pkg/atproto/metadata.go

package atproto

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
	"time"
)

// AppviewMetadata contains branding and configuration from the appview.
type AppviewMetadata struct {
	ClientName      string   `json:"clientName"`
	ClientShortName string   `json:"clientShortName"`
	BaseURL         string   `json:"baseUrl"`
	FaviconURL      string   `json:"faviconUrl"`
	RegistryDomains []string `json:"registryDomains,omitempty"`
}

// FetchAppviewMetadata fetches metadata from the appview's XRPC endpoint.
func FetchAppviewMetadata(ctx context.Context, appviewURL string) (*AppviewMetadata, error) {
	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
	defer cancel()

	reqURL := appviewURL + AppviewGetMetadata
	req, err := http.NewRequestWithContext(ctx, "GET", reqURL, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to fetch metadata: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("metadata endpoint returned status %d", resp.StatusCode)
	}

	var meta AppviewMetadata
	if err := json.NewDecoder(resp.Body).Decode(&meta); err != nil {
		return nil, fmt.Errorf("failed to decode metadata: %w", err)
	}

	return &meta, nil
}

// DefaultAppviewMetadata returns fallback metadata derived from the appview URL.
func DefaultAppviewMetadata(appviewURL string) AppviewMetadata {
	hostname := "ATCR"
	if u, err := url.Parse(appviewURL); err == nil && u.Hostname() != "" {
		hostname = u.Hostname()
	}

	faviconURL := appviewURL + "/favicon-96x96.png"

	return AppviewMetadata{
		ClientName:      hostname,
		ClientShortName: hostname,
		BaseURL:         appviewURL,
		FaviconURL:      faviconURL,
	}
}