start messing about with streaming api

internal/processing/synchronous/streaming/authorize.go

@@ -0,0 +1,33 @@
+package streaming
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+func (p *processor) AuthorizeStreamingRequest(accessToken string) (*gtsmodel.Account, error) {
+	ti, err := p.oauthServer.LoadAccessToken(context.Background(), accessToken)
+	if err != nil {
+		return nil, fmt.Errorf("AuthorizeStreamingRequest: error loading access token: %s", err)
+	}
+
+	uid := ti.GetUserID()
+	if uid == "" {
+		return nil, fmt.Errorf("AuthorizeStreamingRequest: no userid in token")
+	}
+
+	// fetch user's and account for this user id
+	user := &gtsmodel.User{}
+	if err := p.db.GetByID(uid, user); err != nil || user == nil {
+		return nil, fmt.Errorf("AuthorizeStreamingRequest: no user found for validated uid %s", uid)
+	}
+
+	acct := &gtsmodel.Account{}
+	if err := p.db.GetByID(user.AccountID, acct); err != nil || acct == nil {
+		return nil, fmt.Errorf("AuthorizeStreamingRequest: no account retrieved for user with id %s", uid)
+	}
+
+	return acct, nil
+}