Extract authn & authz utils

Signed-off-by: Émile Ré <emile@getprobo.com>

pkg/server/api/authz/authorization.go

@@ -0,0 +1,84 @@
+// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package authz
+
+import (
+	"context"
+	"errors"
+
+	"go.gearno.de/kit/log"
+	"go.probo.inc/probo/pkg/gid"
+	"go.probo.inc/probo/pkg/iam"
+	"go.probo.inc/probo/pkg/server/api/authn"
+	"go.probo.inc/probo/pkg/server/gqlutils"
+)
+
+type (
+	AuthorizeFuncOption func(*iam.AuthorizeParams)
+	AuthorizeFunc       func(context.Context, gid.GID, string, ...AuthorizeFuncOption) error
+)
+
+func WithAttr(key, value string) AuthorizeFuncOption {
+	return func(params *iam.AuthorizeParams) {
+		params.ResourceAttributes[key] = value
+	}
+}
+
+func WithSession(sessionID *gid.GID) AuthorizeFuncOption {
+	return func(params *iam.AuthorizeParams) {
+		params.Session = sessionID
+	}
+}
+
+func NewAuthorizeFunc(
+	svc *iam.Service,
+	logger *log.Logger,
+) AuthorizeFunc {
+	return func(
+		ctx context.Context,
+		objectID gid.GID,
+		action string,
+		options ...AuthorizeFuncOption,
+	) error {
+		identity := authn.IdentityFromContext(ctx)
+		session := authn.SessionFromContext(ctx)
+
+		params := iam.AuthorizeParams{
+			Principal:          identity.ID,
+			Resource:           objectID,
+			Action:             action,
+			ResourceAttributes: make(map[string]string),
+		}
+		if session != nil {
+			params.Session = &session.ID
+		}
+
+		for _, option := range options {
+			option(&params)
+		}
+
+		if err := svc.Authorizer.Authorize(ctx, params); err != nil {
+			var errInsufficientPermissions *iam.ErrInsufficientPermissions
+			if errors.As(err, &errInsufficientPermissions) {
+				return gqlutils.Forbidden(ctx, err)
+			}
+
+			logger.ErrorCtx(ctx, "cannot authorize", log.Error(err))
+			return gqlutils.Internal(ctx)
+		}
+
+		return nil
+	}
+}