From 8b85932d87fe4810b8092b30f379034aa2bad999 Mon Sep 17 00:00:00 2001
From: Brendan Abolivier <contact@brendanabolivier.com>
Date: Thu, 31 Aug 2017 15:42:43 +0100
Subject: [PATCH] Add structures and functions to interact with an ID server

---
 .../dendrite/clientapi/threepid/threepid.go   | 120 ++++++++++++++++++
 1 file changed, 120 insertions(+)
 create mode 100644 src/github.com/matrix-org/dendrite/clientapi/threepid/threepid.go

diff --git a/src/github.com/matrix-org/dendrite/clientapi/threepid/threepid.go b/src/github.com/matrix-org/dendrite/clientapi/threepid/threepid.go
new file mode 100644
index 000000000..682588c87
--- /dev/null
+++ b/src/github.com/matrix-org/dendrite/clientapi/threepid/threepid.go
@@ -0,0 +1,120 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// 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 threepid
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+// EmailAssociationRequest represents the request defined at https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-client-r0-register-email-requesttoken
+type EmailAssociationRequest struct {
+	IDServer    string `json:"id_server"`
+	Secret      string `json:"client_secret"`
+	Email       string `json:"email"`
+	SendAttempt int    `json:"send_attempt"`
+}
+
+// EmailAssociationCheckRequest represents the request defined at https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-client-r0-account-3pid
+type EmailAssociationCheckRequest struct {
+	Creds Credentials `json:"threePidCreds"`
+	Bind  bool        `json:"bind"`
+}
+
+// Credentials represents the "ThreePidCredentials" structure defined at https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-client-r0-account-3pid
+type Credentials struct {
+	SID      string `json:"sid"`
+	IDServer string `json:"id_server"`
+	Secret   string `json:"client_secret"`
+}
+
+// CreateSession creates a session on an identity server.
+// Returns the session's ID.
+// Returns an error if there was a problem sending the request or decoding the
+// response, or if the identity server responded with a non-OK status.
+func CreateSession(req EmailAssociationRequest) (string, error) {
+	// Create a session on the ID server
+	postURL := fmt.Sprintf("https://%s/_matrix/identity/api/v1/validate/email/requestToken", req.IDServer)
+
+	data := url.Values{}
+	data.Add("client_secret", req.Secret)
+	data.Add("email", req.Email)
+	data.Add("send_attempt", strconv.Itoa(req.SendAttempt))
+
+	request, err := http.NewRequest("POST", postURL, strings.NewReader(data.Encode()))
+	if err != nil {
+		return "", err
+	}
+	request.Header.Add("Content-Type", "application/x-www-form-urlencoded")
+
+	client := http.Client{}
+	resp, err := client.Do(request)
+	if err != nil {
+		return "", err
+	}
+
+	// Error if the status isn't OK
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("Could not create a session on the server %s", req.IDServer)
+	}
+
+	// Extract the SID from the response and return it
+	var sid struct {
+		SID string `json:"sid"`
+	}
+	err = json.NewDecoder(resp.Body).Decode(&sid)
+
+	return sid.SID, err
+}
+
+// CheckAssociation checks the status of an ongoing association validation on an
+// identity server.
+// Returns a boolean set to true if the association has been validated, false if not.
+// If the association has been validated, also returns the related third-party
+// identifier.
+// Returns an error if there was a problem sending the request or decoding the
+// response, or if the identity server responded with a non-OK status.
+func CheckAssociation(creds Credentials) (bool, string, error) {
+	url := fmt.Sprintf("https://%s/_matrix/identity/api/v1/3pid/getValidated3pid?sid=%s&client_secret=%s", creds.IDServer, creds.SID, creds.Secret)
+	resp, err := http.Get(url)
+	if err != nil {
+		return false, "", err
+	}
+
+	var respBody struct {
+		Medium      string `json:"medium"`
+		ValidatedAt int64  `json:"validated_at"`
+		Address     string `json:"address"`
+		ErrCode     string `json:"errcode"`
+		Error       string `json:"error"`
+	}
+
+	if err = json.NewDecoder(resp.Body).Decode(&respBody); err != nil {
+		return false, "", err
+	}
+
+	if respBody.ErrCode == "M_SESSION_NOT_VALIDATED" {
+		return false, "", nil
+	} else if len(respBody.ErrCode) > 0 {
+		return false, "", errors.New(respBody.Error)
+	}
+
+	return true, respBody.Address, nil
+}