Support for m.login.token (#2014)

* Add GOPATH to PATH in find-lint.sh.

The user doesn't necessarily have it in PATH.

* Refactor LoginTypePassword and Type to support m.login.token and m.login.sso.

For login token:

* m.login.token will require deleting the token after completeAuth has
  generated an access token, so a cleanup function is returned by
  Type.Login.
* Allowing different login types will require parsing the /login body
  twice: first to extract the "type" and then the type-specific parsing.
  Thus, we will have to buffer the request JSON in /login, like
  UserInteractive already does.

For SSO:

* NewUserInteractive will have to also use GetAccountByLocalpart. It
  makes more sense to just pass a (narrowed-down) accountDB interface
  to it than adding more function pointers.

Code quality:

* Passing around (and down-casting) interface{} for login request types
  has drawbacks in terms of type-safety, and no inherent benefits. We
  always decode JSON anyway. Hence renaming to Type.LoginFromJSON. Code
  that directly uses LoginTypePassword with parsed data can still use
  Login.
* Removed a TODO for SSO. This is already tracked in #1297.
* httputil.UnmarshalJSON is useful because it returns a JSONResponse.

This change is intended to have no functional changes.

* Support login tokens in User API.

This adds full lifecycle functions for login tokens: create, query, delete.

* Support m.login.token in /login.

* Fixes for PR review.

* Set @matrix-org/dendrite-core as repository code owner

* Return event NID from `StoreEvent`, match PSQL vs SQLite behaviour, tweak backfill persistence (#2071)

Co-authored-by: kegsay <kegan@matrix.org>
Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>

userapi/api/api.go

@@ -24,6 +24,8 @@ import (
 
 // UserInternalAPI is the internal API for information about users and devices.
 type UserInternalAPI interface {
+	LoginTokenInternalAPI
+
 	InputAccountData(ctx context.Context, req *InputAccountDataRequest, res *InputAccountDataResponse) error
 	PerformAccountCreation(ctx context.Context, req *PerformAccountCreationRequest, res *PerformAccountCreationResponse) error
 	PerformPasswordUpdate(ctx context.Context, req *PerformPasswordUpdateRequest, res *PerformPasswordUpdateResponse) error

userapi/api/api_logintoken.go

@@ -0,0 +1,69 @@
+// Copyright 2021 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package api
+
+import (
+	"context"
+	"time"
+)
+
+type LoginTokenInternalAPI interface {
+	// PerformLoginTokenCreation creates a new login token and associates it with the provided data.
+	PerformLoginTokenCreation(ctx context.Context, req *PerformLoginTokenCreationRequest, res *PerformLoginTokenCreationResponse) error
+
+	// PerformLoginTokenDeletion ensures the token doesn't exist. Success
+	// is returned even if the token didn't exist, or was already deleted.
+	PerformLoginTokenDeletion(ctx context.Context, req *PerformLoginTokenDeletionRequest, res *PerformLoginTokenDeletionResponse) error
+
+	// QueryLoginToken returns the data associated with a login token. If
+	// the token is not valid, success is returned, but res.Data == nil.
+	QueryLoginToken(ctx context.Context, req *QueryLoginTokenRequest, res *QueryLoginTokenResponse) error
+}
+
+// LoginTokenData is the data that can be retrieved given a login token. This is
+// provided by the calling code.
+type LoginTokenData struct {
+	// UserID is the full mxid of the user.
+	UserID string
+}
+
+// LoginTokenMetadata contains metadata created and maintained by the User API.
+type LoginTokenMetadata struct {
+	Token      string
+	Expiration time.Time
+}
+
+type PerformLoginTokenCreationRequest struct {
+	Data LoginTokenData
+}
+
+type PerformLoginTokenCreationResponse struct {
+	Metadata LoginTokenMetadata
+}
+
+type PerformLoginTokenDeletionRequest struct {
+	Token string
+}
+
+type PerformLoginTokenDeletionResponse struct{}
+
+type QueryLoginTokenRequest struct {
+	Token string
+}
+
+type QueryLoginTokenResponse struct {
+	// Data is nil if the token was invalid.
+	Data *LoginTokenData
+}

userapi/api/api_trace_logintoken.go

@@ -0,0 +1,39 @@
+// Copyright 2021 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package api
+
+import (
+	"context"
+
+	"github.com/matrix-org/util"
+)
+
+func (t *UserInternalAPITrace) PerformLoginTokenCreation(ctx context.Context, req *PerformLoginTokenCreationRequest, res *PerformLoginTokenCreationResponse) error {
+	err := t.Impl.PerformLoginTokenCreation(ctx, req, res)
+	util.GetLogger(ctx).Infof("PerformLoginTokenCreation req=%+v res=%+v", js(req), js(res))
+	return err
+}
+
+func (t *UserInternalAPITrace) PerformLoginTokenDeletion(ctx context.Context, req *PerformLoginTokenDeletionRequest, res *PerformLoginTokenDeletionResponse) error {
+	err := t.Impl.PerformLoginTokenDeletion(ctx, req, res)
+	util.GetLogger(ctx).Infof("PerformLoginTokenDeletion req=%+v res=%+v", js(req), js(res))
+	return err
+}
+
+func (t *UserInternalAPITrace) QueryLoginToken(ctx context.Context, req *QueryLoginTokenRequest, res *QueryLoginTokenResponse) error {
+	err := t.Impl.QueryLoginToken(ctx, req, res)
+	util.GetLogger(ctx).Infof("QueryLoginToken req=%+v res=%+v", js(req), js(res))
+	return err
+}