Auto-update index periodically (#1447)

* Auto-refresh indexes after some time (default 24h)

* ask user on first autoupdate

* User changes

* Test behavior on network failure

doc/user-changes.md

@@ -6,6 +6,18 @@ stay on top of `alr` new features.
 
 ## Release `2.0-dev`
 
+### Automatic index updates
+
+PR [#1447](https://github.com/alire-project/alire/pull/1447)
+
+A new configuration option, `index.auto_update`, allows setting the refresh
+period of indexes. It defaults to 24 hours and the user will be asked the first
+time to allow automatic updates. Setting this option to 0 will also disable
+automatic updates.
+
+When enabled, updates may happen before executing commands that rely on
+indexes: `get`, `search`, `with`, etc.
+
 ### Deprecation of `dependencies.dir` in favor of `dependencies.shared`
 
 PR [#1419](https://github.com/alire-project/alire/pull/1419)

src/alire/alire-config-builtins.ads

@@ -51,6 +51,26 @@ package Alire.Config.Builtins is
         "When unset or true, the community index will be added " &
         "automatically when required if no other index is configured.");
 
+   Index_Auto_Update : constant Builtin := New_Builtin
+     (Key  => "index.auto_update",
+      Kind => Cfg_Int,
+      Def  => "24", -- hours
+      Help =>
+        "Hours between automatic index refresh. Set to 0 to disable.");
+
+   Index_Auto_Update_Asked : constant Builtin := New_Builtin
+     (Key    => "index.auto_update_asked",
+      Def    => False,
+      Public => False,
+      Help   => "First time we must autoupdate, we ask the user to approve");
+
+   Index_Last_Update : constant Builtin := New_Builtin
+     (Key    => "index.last_update",
+      Public => False,
+      Kind   => Cfg_Int,
+      Def    => "0", -- seconds since epoch
+      Help   => "Timestamp of last index auto-refresh (seconds)");
+
    Index_Host : constant Builtin := New_Builtin
      (Key  => "index.host",
       Kind => Cfg_String,

src/alire/alire-config.adb

@@ -16,6 +16,14 @@ package body Alire.Config is
    function Get (This : Builtin_Option) return Boolean
    is (DB.Get (+This.Key, Boolean'Value (+This.Def)));
 
+   ---------
+   -- Get --
+   ---------
+
+   function Get (This : Builtin_Option) return Config_Int
+   is (Config_Int'Value
+       (DB.Get_As_String (+This.Key, +This.Def)));
+
    -----------------
    -- Set_Locally --
    -----------------
@@ -58,6 +66,18 @@ package body Alire.Config is
       Edit.Set_Boolean (Level, +This.Key, Value);
    end Set;
 
+   ---------
+   -- Set --
+   ---------
+
+   procedure Set (This  : Builtin_Option;
+                  Level : Config.Level;
+                  Value : Config_Int)
+   is
+   begin
+      Edit.Set (Level, +This.Key, Value'Image, This.Check);
+   end Set;
+
    -----------
    -- Unset --
    -----------

src/alire/alire-config.ads

@@ -15,6 +15,8 @@ package Alire.Config is
    --  Ordering is important, as Globals are loaded first and overridden by any
    --  Local definition loaded later.
 
+   subtype Config_Int is Long_Long_Integer;
+
    ---------------
    -- Built-ins --
    ---------------
@@ -41,6 +43,7 @@ package Alire.Config is
 
    function Get (This : Builtin_Option) return String;
    function Get (This : Builtin_Option) return Boolean;
+   function Get (This : Builtin_Option) return Config_Int;
 
    procedure Set_Locally (This : Builtin_Option; Value : String);
 
@@ -54,6 +57,10 @@ package Alire.Config is
                   Level : Config.Level;
                   Value : Boolean);
 
+   procedure Set (This  : Builtin_Option;
+                  Level : Config.Level;
+                  Value : Config_Int);
+
    procedure Unset (This  : Builtin_Option;
                     Level : Config.Level);
 

src/alire/alire-index_on_disk-loading.adb

@@ -5,6 +5,7 @@ with Alire.Config.Builtins;
 with Alire.Config.Edit;
 with Alire.Containers;
 with Alire.Index;
+with Alire.Index_On_Disk.Updates;
 with Alire.Platforms.Current;
 with Alire.Provides;
 with Alire.TOML_Adapters;
@@ -46,10 +47,6 @@ package body Alire.Index_On_Disk.Loading is
    --  metadata file doesn't exist, a full index load will be triggered and
    --  the file will be rebuilt.
 
-   procedure Invalidate_Providers (Indexes_Dir : Any_Path);
-   --  Whenever an index is added or updated, we must invalidate the cache on
-   --  disk containing crate virtual providers.
-
    procedure Save_Providers (Indexes_Dir : Any_Path);
    --  Write to disk the providers info already in memory (generated after a
    --  full load).
@@ -196,6 +193,22 @@ package body Alire.Index_On_Disk.Loading is
                             Result,
                             Cached => False);
       use Sets;
+
+      ------------------
+      -- Actually_Add --
+      ------------------
+
+      function Actually_Add (Before : String := "") return Outcome is
+      begin
+         Updates.Reset_Update_Time;
+
+         return Add (Origin => Alire.Index.Community_Repo &
+                       "#" & Alire.Index.Community_Branch,
+                     Name   => Alire.Index.Community_Name,
+                     Under  => Config.Edit.Indexes_Directory,
+                     Before => Before);
+      end Actually_Add;
+
    begin
       if not Config.Builtins.Index_Auto_Community.Get then
          Warnings.Warn_Once
@@ -212,13 +225,9 @@ package body Alire.Index_On_Disk.Loading is
             Trace.Debug ("Index was already set, deleting and re-adding...");
             Assert (Indexes (I).Delete);
 
-            return Add (Origin => Alire.Index.Community_Repo &
-                          "#" & Alire.Index.Community_Branch,
-                        Name   => Alire.Index.Community_Name,
-                        Under  => Config.Edit.Indexes_Directory,
-                        Before => (if Has_Element (Next (I))
-                                   then Indexes (Next (I)).Name
-                                   else ""));
+            return Actually_Add (Before => (if Has_Element (Next (I))
+                                            then Indexes (Next (I)).Name
+                                            else ""));
          end if;
       end loop;
 
@@ -228,10 +237,7 @@ package body Alire.Index_On_Disk.Loading is
       --  Reset cache so next detection finds the new index
 
       Trace.Debug ("Index was not set, adding it...");
-      return Add (Origin => Alire.Index.Community_Repo &
-                    "#" & Alire.Index.Community_Branch,
-                  Name   => Alire.Index.Community_Name,
-                  Under  => Config.Edit.Indexes_Directory);
+      return Actually_Add;
    exception
       when E : Checked_Error =>
          return Outcome_From_Exception (E);
@@ -372,6 +378,20 @@ package body Alire.Index_On_Disk.Loading is
       return Indexes;
    end Find_All;
 
+   ---------------------
+   -- Index_Available --
+   ---------------------
+
+   function Index_Available (Under : Absolute_Path := Default_Path)
+                             return Boolean
+   is
+      Result  : Outcome;
+      Index   : constant Set := Find_All (Under, Result);
+   begin
+      Result.Assert;
+      return not Index.Is_Empty;
+   end Index_Available;
+
    ----------
    -- Load --
    ----------
@@ -628,38 +648,4 @@ package body Alire.Index_On_Disk.Loading is
          end if;
    end Save_Providers;
 
-   ----------------
-   -- Update_All --
-   ----------------
-
-   function Update_All (Under : Absolute_Path) return Outcome is
-      Result  : Outcome;
-      Indexes : constant Set := Find_All (Under, Result);
-   begin
-      if not Result.Success then
-         return Result;
-      end if;
-
-      --  First, invalidate providers metadata as this may change with the
-      --  update.
-
-      Invalidate_Providers (Under);
-
-      --  Now update normally
-
-      for Index of Indexes loop
-         declare
-            Result : constant Outcome := Index.Update;
-         begin
-            if Result.Success then
-               Trace.Detail ("Updated successfully: " & Index.Origin);
-            else
-               return Result;
-            end if;
-         end;
-      end loop;
-
-      return Outcome_Success;
-   end Update_All;
-
 end Alire.Index_On_Disk.Loading;

src/alire/alire-index_on_disk-loading.ads

@@ -31,6 +31,10 @@ package Alire.Index_On_Disk.Loading is
    --  instead of proceeding with default behaviors, such as getting the
    --  community index.
 
+   function Index_Available (Under : Absolute_Path := Default_Path)
+                             return Boolean;
+   --  Says if there's any available index configured
+
    procedure Setup (From : Absolute_Path := Default_Path);
    --  If no index is configured, set up the default community index
 
@@ -51,9 +55,6 @@ package Alire.Index_On_Disk.Loading is
    --  If no path for detection is given, default one is used.
    --  May raise Checked_Error. Loading twice the same crate is idempotent.
 
-   function Update_All (Under : Absolute_Path) return Outcome;
-   --  Find and update all indexes at given location
-
    function Add (Origin : URL;
                  Name   : String;
                  Under  : Absolute_Path;
@@ -70,6 +71,10 @@ package Alire.Index_On_Disk.Loading is
    procedure Drop_Index_Cache;
    --  Force detection of indexes on disk on next call to Find_All
 
+   procedure Invalidate_Providers (Indexes_Dir : Any_Path);
+   --  Whenever an index is added or updated, we must invalidate the cache on
+   --  disk containing crate virtual providers.
+
 private
 
    function Default return Set is (Sets.Empty_Set with null record);