[evolution-data-server] [OAuth2] Add GSettings keys to override client ID and secret

[Milan Crha <mcrha src gnome org>]

commit 3824aa3b88461f0d92f4bab2e674372d8eac629b
Author: Milan Crha <mcrha redhat com>
Date:   Mon Feb 11 11:49:38 2019 +0100

    [OAuth2] Add GSettings keys to override client ID and secret
    
    The built-in OAuth2 service for Google and Outlook had only build-time
    options to specify the client ID and secret, which is quite limiting
    and unnecessarily complicated. The GSettings keys make it much simpler
    to override the build-time values.

 .../org.gnome.evolution-data-server.gschema.xml.in | 20 +++++++++
 src/libedataserver/e-oauth2-service-google.c       | 46 +++++++++++++++++++
 src/libedataserver/e-oauth2-service-outlook.c      | 52 ++++++++++++++++++++--
 3 files changed, 115 insertions(+), 3 deletions(-)
---
diff --git a/data/org.gnome.evolution-data-server.gschema.xml.in 
b/data/org.gnome.evolution-data-server.gschema.xml.in
index 27b2e0dd8..50857216d 100644
--- a/data/org.gnome.evolution-data-server.gschema.xml.in
+++ b/data/org.gnome.evolution-data-server.gschema.xml.in
@@ -46,5 +46,25 @@
          Company:mail.company.com — enables “Company” OAuth2 authentication for “mail.company.com” host
         Company-CalDAV:caldav.company.com — enables “Company” OAuth2 authentication for any “CalDAV” source, 
which reads data from “caldav.company.com” host</_description>
     </key>
+    <key name="oauth2-google-client-id" type="s">
+      <default>''</default>
+      <_summary>An OAuth2 client ID to use to connect to Google servers, instead of the one provided during 
build time</_summary>
+      <_description>User-specified OAuth2 client ID for Google servers. Empty string means to use the one 
provided during build time. Change of this requires restart.</_description>
+    </key>
+    <key name="oauth2-google-client-secret" type="s">
+      <default>''</default>
+      <_summary>An OAuth2 client secret to use to connect to Google servers, instead of the one provided 
during build time</_summary>
+      <_description>User-specified OAuth2 client secret for Google servers. Empty string means to use the 
one provided during build time. Change of this requires restart.</_description>
+    </key>
+    <key name="oauth2-outlook-client-id" type="s">
+      <default>''</default>
+      <_summary>An OAuth2 client ID to use to connect to Outlook servers, instead of the one provided during 
build time</_summary>
+      <_description>User-specified OAuth2 client ID for Outlook servers. Empty string means to use the one 
provided during build time. Change of this requires restart.</_description>
+    </key>
+    <key name="oauth2-outlook-client-secret" type="s">
+      <default>''</default>
+      <_summary>An OAuth2 client secret to use to connect to Outlook servers, instead of the one provided 
during build time</_summary>
+      <_description>User-specified OAuth2 client secret for Outlook servers. Empty string means to use the 
one provided during build time. Change of this requires restart.</_description>
+    </key>
   </schema>
 </schemalist>
diff --git a/src/libedataserver/e-oauth2-service-google.c b/src/libedataserver/e-oauth2-service-google.c
index c380c61ce..f0c6f2cbf 100644
--- a/src/libedataserver/e-oauth2-service-google.c
+++ b/src/libedataserver/e-oauth2-service-google.c
@@ -56,10 +56,49 @@ eos_google_get_display_name (EOAuth2Service *service)
        return C_("OAuth2Service", "Google");
 }
 
+static const gchar *
+eos_google_read_settings (EOAuth2Service *service,
+                         const gchar *key_name)
+{
+       G_LOCK_DEFINE_STATIC (user_settings);
+       gchar *value;
+
+       G_LOCK (user_settings);
+
+       value = g_object_get_data (G_OBJECT (service), key_name);
+       if (!value) {
+               GSettings *settings;
+
+               settings = g_settings_new ("org.gnome.evolution-data-server");
+               value = g_settings_get_string (settings, key_name);
+               g_object_unref (settings);
+
+               if (value && *value) {
+                       g_object_set_data_full (G_OBJECT (service), key_name, value, g_free);
+               } else {
+                       g_free (value);
+                       value = (gchar *) "";
+
+                       g_object_set_data (G_OBJECT (service), key_name, value);
+               }
+       }
+
+       G_UNLOCK (user_settings);
+
+       return value;
+}
+
 static const gchar *
 eos_google_get_client_id (EOAuth2Service *service,
                          ESource *source)
 {
+       const gchar *client_id;
+
+       client_id = eos_google_read_settings (service, "oauth2-google-client-id");
+
+       if (client_id && *client_id)
+               return client_id;
+
        return GOOGLE_CLIENT_ID;
 }
 
@@ -67,6 +106,13 @@ static const gchar *
 eos_google_get_client_secret (EOAuth2Service *service,
                              ESource *source)
 {
+       const gchar *client_secret;
+
+       client_secret = eos_google_read_settings (service, "oauth2-google-client-secret");
+
+       if (client_secret && *client_secret)
+               return client_secret;
+
        return GOOGLE_CLIENT_SECRET;
 }
 
diff --git a/src/libedataserver/e-oauth2-service-outlook.c b/src/libedataserver/e-oauth2-service-outlook.c
index cbc456b61..687c10d3b 100644
--- a/src/libedataserver/e-oauth2-service-outlook.c
+++ b/src/libedataserver/e-oauth2-service-outlook.c
@@ -57,10 +57,49 @@ eos_outlook_get_display_name (EOAuth2Service *service)
        return C_("OAuth2Service", "Outlook");
 }
 
+static const gchar *
+eos_outlook_read_settings (EOAuth2Service *service,
+                          const gchar *key_name)
+{
+       G_LOCK_DEFINE_STATIC (user_settings);
+       gchar *value;
+
+       G_LOCK (user_settings);
+
+       value = g_object_get_data (G_OBJECT (service), key_name);
+       if (!value) {
+               GSettings *settings;
+
+               settings = g_settings_new ("org.gnome.evolution-data-server");
+               value = g_settings_get_string (settings, key_name);
+               g_object_unref (settings);
+
+               if (value && *value) {
+                       g_object_set_data_full (G_OBJECT (service), key_name, value, g_free);
+               } else {
+                       g_free (value);
+                       value = (gchar *) "";
+
+                       g_object_set_data (G_OBJECT (service), key_name, value);
+               }
+       }
+
+       G_UNLOCK (user_settings);
+
+       return value;
+}
+
 static const gchar *
 eos_outlook_get_client_id (EOAuth2Service *service,
                           ESource *source)
 {
+       const gchar *client_id;
+
+       client_id = eos_outlook_read_settings (service, "oauth2-outlook-client-id");
+
+       if (client_id && *client_id)
+               return client_id;
+
        return OUTLOOK_CLIENT_ID;
 }
 
@@ -68,12 +107,19 @@ static const gchar *
 eos_outlook_get_client_secret (EOAuth2Service *service,
                               ESource *source)
 {
-       const gchar *secret = OUTLOOK_CLIENT_SECRET;
+       const gchar *client_secret;
+
+       client_secret = eos_outlook_read_settings (service, "oauth2-outlook-client-secret");
+
+       if (client_secret && *client_secret)
+               return client_secret;
+
+       client_secret = OUTLOOK_CLIENT_SECRET;
 
-       if (secret && !*secret)
+       if (client_secret && !*client_secret)
                return NULL;
 
-       return secret;
+       return client_secret;
 }
 
 static const gchar *