Added openwisp-update-config script #19

openwisp-config/Makefile

@@ -70,6 +70,10 @@ define Package/openwisp-config/install
 	$(INSTALL_BIN) \
 		files/sbin/openwisp-uci-autoname.lua \
 		$(1)/usr/sbin/openwisp-uci-autoname
+
+	$(INSTALL_BIN) \
+		files/sbin/openwisp-update-config.lua \
+		$(1)/usr/sbin/openwisp-update-config
 endef
 
 $(eval $(call BuildPackage,openwisp-config))

openwisp-config/files/sbin/openwisp-update-config.lua

@@ -0,0 +1,154 @@
+#!/usr/bin/env lua
+-- openwisp-config configuration updater
+
+require('os')
+require('lfs')
+require('uci')
+require('openwisp.utils')
+
+MERGE = true
+
+downloaded_conf = '/tmp/openwisp/configuration.tar.gz'
+openwisp_dir = '/etc/openwisp'
+standard_config_dir = '/etc/config'
+remote_dir = openwisp_dir .. '/remote'
+remote_config_dir = remote_dir .. standard_config_dir
+stored_dir = openwisp_dir .. '/stored'
+added_file = openwisp_dir .. '/added.list'
+modified_file = openwisp_dir .. '/modified.list'
+get_standard = function() return uci.cursor(standard_config_dir) end
+get_remote = function() return uci.cursor(remote_config_dir, '/tmp/openwisp/.uci') end
+
+-- uci cursors
+standard = get_standard()
+remote = get_remote()
+
+-- update UCI configuration
+-- (overwrite or merge)
+
+-- remove config items added via openwisp-config
+if lfs.attributes(remote_config_dir, 'mode') == 'directory' then
+    for file in lfs.dir(remote_config_dir) do
+        local standard_path = standard_config_dir .. '/' .. file
+        if lfs.attributes(standard_path, 'mode') == 'file' then
+            remote:foreach(file, nil, function(section)
+                remove_uci_options(standard, file, section)
+            end)
+            standard:commit(file)
+            -- remove uci file if empty
+            local uci = standard:get_all(file)
+            if uci and is_table_empty(uci) then
+                os.remove(standard_path)
+            end
+        end
+    end
+end
+
+-- persist remote config in /etc/openwisp/remote
+os.execute('rm -rf '..remote_dir)
+os.execute('mkdir -p '..remote_dir)
+os.execute('tar -zxf '..downloaded_conf..' -C '..remote_dir)
+-- reload uci cursors
+standard = get_standard()
+remote = get_remote()
+
+if lfs.attributes(remote_config_dir, 'mode') == 'directory' then
+    -- loop over each file in new remote uci config
+    for file in lfs.dir(remote_config_dir) do
+        local standard_path = standard_config_dir .. '/' .. file
+        local remote_path = remote_config_dir .. '/' .. file
+        -- ensure we are acting on a file
+        if lfs.attributes(remote_path, 'mode') == 'file' then
+            -- MERGE mode
+            if MERGE then
+                -- avoid "file does not exist" error
+                os.execute('touch ' .. standard_path)
+                remote:foreach(file, nil, function(section)
+                    write_uci_section(standard, file, section)
+                end)
+                standard:commit(file)
+            -- OVERWRITE mode
+            else
+                os.execute('cp '..remote_config_dir..'/* '..standard_config_dir)
+            end
+        end
+    end
+end
+
+-- ensure list files exist
+os.execute('touch ' .. added_file)
+os.execute('touch ' .. modified_file)
+-- convert lists to lua sets
+added = file_to_set(added_file)
+modified = file_to_set(modified_file)
+added_changed = false
+modified_changed = false
+
+-- loop each file except directories and standard UCI config files
+ignored_path = remote_config_dir .. '/'
+
+for path, attr in dirtree(remote_dir) do
+    if attr.mode == 'file' and string.sub(path, 1, 32) ~= ignored_path then
+        -- calculates destination dir
+        local dest_path = string.sub(path, 21)
+        local dest_dir = dirname(dest_path)
+        local is_added = added[dest_path] == true
+        local is_modified = modified[dest_path] == true
+        -- if file is neither in added.list nor modified.list
+        if is_added == false and is_modified == false then
+            -- if file exists
+            if file_exists(dest_path) then
+                -- add file path to modified set
+                modified[dest_path] = true
+                modified_changed = true
+                -- store original in /etc/openwisp/stored/<path>
+                os.execute('mkdir -p '..stored_dir..dest_dir)
+                os.execute('cp '..dest_path..' '..stored_dir..dest_path)
+            else
+                -- add file path added set
+                added[dest_path] = true
+                added_changed = true
+            end
+        end
+        -- add file to filesystem
+        os.execute('mkdir -p '..dest_dir)
+        os.execute('cp '..path..' '..dest_path)
+    end
+end
+
+-- remove files that have been added via openwisp
+-- which are not present anymore
+for file, bool in pairs(added) do
+    local remote_path = remote_dir .. file
+    -- if file is not in /etc/openwisp/remote anymore
+    if not file_exists(remote_path) then
+        -- remove file
+        os.remove(file)
+        -- remove dir if empty
+        lfs.rmdir(dirname(file))
+        -- remove entry from added set
+        added[file] = nil
+        added_changed = true
+    end
+end
+
+-- restore pre-existing files that were changed via openwisp
+-- which are not present anymore
+for file, bool in pairs(modified) do
+    local remote_path = remote_dir .. file
+    local stored_path = stored_dir .. file
+    -- if file is not in /etc/openwisp/remote anymore
+    if not file_exists(remote_path) then
+        -- restore original file
+        os.execute('mv '..stored_path..' '..file)
+        -- remove stored dir if empty
+        lfs.rmdir(dirname(stored_path))
+        -- remove entry from modified set
+        modified[file] = nil
+        modified_changed = true
+    end
+end
+
+-- persist changes to file lists
+if added_changed then set_to_file(added, added_file) end
+if modified_changed then set_to_file(modified, modified_file) end