doc(binding/lua): add ldoc generactor for lua binding

.github/workflows/docs.yml

@@ -163,6 +163,25 @@ jobs:
         with:
           name: C-docs
           path: ./bindings/c/docs/doxygen/html
+  build-lua-doc:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup lua-ldoc
+        run: sudo apt-get install lua-ldoc
+
+      - name: Build Docs
+        working-directory: "bindings/lua"
+        run: ldoc ./src
+
+      - name: Upload docs
+        uses: actions/upload-artifact@v3
+        with:
+          name: lua-docs
+          path: ./bindings/lua/doc/
+
 
   build-website:
     runs-on: ubuntu-latest
@@ -216,6 +235,12 @@ jobs:
           name: C-docs
           path: ./website/static/docs/c
 
+      - name: Download lua docs
+        uses: actions/download-artifact@v3
+        with:
+          name: lua-docs
+          path: ./website/static/docs/lua
+
       - name: Install Dependencies
         working-directory: website
         run: yarn install --immutable

bindings/lua/src/metadata_doc.lua

@@ -0,0 +1,41 @@
+--[[
+
+    Licensed to the Apache Software Foundation (ASF) under one
+    or more contributor license agreements.  See the NOTICE file
+    distributed with this work for additional information
+    regarding copyright ownership.  The ASF licenses this file
+    to you 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.
+
+]]
+
+
+--- OpenDAL metadata It must be returned operator::stat()
+-- @classmod opendal.metadata
+-- @pragma nostrip
+
+local _M = {}
+
+--- Return whether the path represents a file
+-- @return bool if it is file, otherwise false
+-- @function is_file
+
+--- Return whether the path represents a directory
+-- @return bool if it is directory, otherwise false
+-- @function is_dir
+
+--- Return the content_length of the metadata
+-- @return bool if it is directory, otherwise false
+-- @function content_length
+
+return _M

bindings/lua/src/operator_doc.lua

@@ -0,0 +1,69 @@
+--[[
+
+    Licensed to the Apache Software Foundation (ASF) under one
+    or more contributor license agreements.  See the NOTICE file
+    distributed with this work for additional information
+    regarding copyright ownership.  The ASF licenses this file
+    to you 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.
+
+]]
+
+--- OpenDAL operator.
+-- @classmod opendal.operator
+-- @pragma nostrip
+
+local _M = {}
+
+--- Construct an operator based on scheme and option. Uses an table of key-value pairs to initialize 
+--- the operator based on provided scheme and options. For each scheme, i.e. Backend, 
+--- different options could be set, you may  reference the https://opendal.apache.org/docs/category/services/
+--- for each service, especially for the **Configuration Part**.
+-- @param string scheme the service scheme you want to specify, e.g. "fs", "s3", "supabase"
+-- @param table options the table to the options for this operators
+-- @return table, error  opendal operator table which contain opendal operator instance, error nil if success, others otherwise
+-- @function new
+
+
+--- Blockingly write raw bytes to path. 
+---  Write the bytes into the path blockingly, returns nil if success, others otherwise
+-- @param string path the designated path you want to write your bytes in
+-- @param string bytes the bytes to be written
+-- @return error nil if success, otherwise error message
+-- @function write
+
+--- Blockingly read raw bytes from path. 
+---  Read the data out from `path` blockingly by operator, returns the string if success, others otherwise
+-- @param string path the designated path you want to write your bytes in
+-- @return string, error read data, error nil if success, otherwise error message
+-- @function read
+
+--- Blockingly delete the object in path.
+---  Delete the object in path blockingly, returns error nil
+---  if success, others otherwise
+-- @param string path the designated path you want to write your delete
+-- @return error error nil if success, otherwise error message
+-- @function delete
+
+--- Check whether the path exists.
+-- @param string path the designated path you want to write your delete
+-- @return bool, error true or false depend on operator instance and path, error nil if success, otherwise error message
+-- @function is_exist
+
+--- Stat the path, return its metadata.
+-- @param string ,path the designated path you want to write your delete
+-- @return table , error opendal.metadata instance table, error nil if success, otherwise error message
+-- @function stat
+
+
+return _M