Safer & cleaner database updates

lib/miga/cli/action/db.rb

@@ -80,15 +80,15 @@ def perform
     cli.puts "# Host: #{manif[:host]}"
     cli.puts "# Manifest last update: #{manif[:last_update]}"
     list_databases(manif) and return
-    db = db_requested(manif)
+    db_sym, db = db_requested(manif)
     list_versions(db) and return
     ver = version_requested(db)
     check_target and return
 
     # Download and expand
     file = download_file(@ftp, ver[:path], cli[:reuse_archive])
     check_digest(ver, file)
-    unarchive(file)
+    unarchive(file, db_sym.to_s)
     register_database(manif, db, ver)
   end
 
@@ -168,7 +168,7 @@ def db_requested(manif)
     db = manif[:databases][cli[:database]]
     raise 'Cannot find database in this host' if db.nil?
 
-    db
+    [cli[:database], db]
   end
 
   def version_requested(db)
@@ -240,13 +240,28 @@ def version_size(ver)
       cli.num_suffix(ver[:size_unarchived], true) + ')'
   end
 
-  def unarchive(file)
+  def unarchive(file, db_name)
     cli.say "Unarchiving #{file}"
+    tmp_archive = File.join(cli[:local], '.TMP_ARCHIVE')
+    FileUtils.mkdir_p(tmp_archive)
     MiGA::MiGA.run_cmd <<~CMD
-      cd #{cli[:local].shellescape} \
+      cd #{tmp_archive.shellescape} \
         && tar -zxf #{file.shellescape} \
         && rm #{file.shellescape}
     CMD
+
+    target = File.join(cli[:local], db_name)
+    source = File.join(tmp_archive, db_name)
+    if Dir.exist?(target)
+      cli.say 'Replacing previous version'
+      tmp = File.join(tmp_archive, "#{db_name}.old")
+      File.rename(target, tmp)
+      File.rename(source, target)
+      File.rm_rf(tmp)
+    else
+      File.rename(source, target)
+    end
+    Dir.unlink(tmp_archive) if Dir.empty?(tmp_archive)
   end
 
   def register_database(manif, db, ver)

lib/miga/cli/action/env.rb

@@ -10,8 +10,8 @@ def parse_cli
 
   def perform
     puts <<~BASH
-      MIGA="#{MiGA::MiGA.root_path}"
-      MIGA_HOME=${MIGA_HOME:-"$HOME"}
+      export MIGA="#{MiGA::MiGA.root_path}"
+      export MIGA_HOME=${MIGA_HOME:-"$HOME"}
       . "$MIGA_HOME/.miga_rc"
       # Ensure MiGA & submodules are first in PATH
       export PATH="$MIGA/bin:$PATH"

lib/miga/version.rb

@@ -12,15 +12,15 @@ module MiGA
   # - String indicating release status:
   #   - rc* release candidate, not released as gem
   #   - [0-9]+ stable release, released as gem
-  VERSION = [1.3, 15, 6].freeze
+  VERSION = [1.3, 15, 7].freeze
 
   ##
   # Nickname for the current major.minor version.
   VERSION_NAME = 'mezzotint'
 
   ##
   # Date of the current gem relese.
-  VERSION_DATE = Date.new(2024, 6, 5)
+  VERSION_DATE = Date.new(2024, 6, 17)
 
   ##
   # References of MiGA