update documentation

Author: mailsvb

docs/handler.md

@@ -20,10 +20,7 @@ To get an FTP server running quickly, the below code will get you started by all
 ```{code-block} javascript
 const { ftpd } = require('jsftpd')
 
-const server = new ftpd({cnf: {username: 'john', password: 'doe'})
-
-server.on('log', console.log)
-server.on('error', console.error)
+const server = new ftpd({cnf: {username: 'john', password: 'doe', basefolder: '/tmp'})
 
 server.start()
 ```

docs/index.md

@@ -1,13 +1,14 @@
 # Configuration
 
-jsftpd takes an object when a new instance is created. This object can contain two properties:
+jsftpd takes an object when a new instance is created. This object can have different properties:
 
 ```{code-block} javascript
-new ftpd({tls: {...}, cnf: {...}})
+new ftpd({tls: {...}, cnf: {...}, hdl: {...}})
 ```
 
 * **tls**: TLS options. Takes any option as per node.js tls.createServer
 * **cnf**: jsftpd specific configuration items
+* **hdl**: jsftpd handler for specific FTP commands
 
 ## tls
 
@@ -284,3 +285,99 @@ Allow the anonymous user to create folders.
 ```{code-block} javascript
 new ftpd({cnf: {allowAnonymousFolderCreate: true}})
 ```
+
+## hdl
+
+jsftpd can use handler functions instead of reading/writing to the file system for several FTP commands.
+
+```{code-block} javascript
+const handler = {
+    upload: async function (...) {},
+    download: async function (...) {},
+    list: async function (...) {},
+    rename: async function (...) {}
+}
+const server = new ftpd({hdl: handler})
+```
+
+The following FTP commands are covered by the handlers
+
+* **STOR**: Uploading files to the FTP server
+* **RETR**: Downloading files from the FTP server
+* **LIST**: Listing directory contents on the FTP server
+* **MLSD**: Listing directory contents on the FTP server
+* **RNFR**: Renaming files on the FTP server
+* **RNTO**: Renaming files on the FTP server
+
+### upload
+
+**Name: `upload`**\
+**Returns: `boolean`**
+
+The upload function takes 5 arguments when being called from jsftpd. It must return `true` on success or `false` on any error handling the file upload.
+
+**username: `string` the user who has uploaded the file**\
+**path: `string` relative path on the FTP server where the file is stored**\
+**fileName: `string` the name of the file that is stored**\
+**data: `Buffer` the file content that is stored**\
+**offset: `number` the offset of the data received**
+
+```{code-block} javascript
+async upload (username, path, fileName, data, offset) {
+    ...
+}
+```
+
+### download
+
+**Name: `upload`**\
+**Returns: `Buffer`**
+
+The download function takes 4 arguments when being called from jsftpd. It must return the file content as a `Buffer`.
+
+**username: `string` the user who has uploaded the file**\
+**path: `string` relative path on the FTP server where the file is stored**\
+**fileName: `string` the name of the file that is stored**\
+**data: `Buffer` the file content that is stored**\
+**offset: `number` the offset of the data received**
+
+```{code-block} javascript
+async upload (username, path, fileName, data, offset) {
+    ...
+}
+```
+
+### list
+
+**Name: `list`**\
+**Returns: `string`**
+
+The list function takes 3 arguments when being called from jsftpd. It must return the content of the specified directory as a `string`.
+
+**username: `string` the current user**\
+**path: `string` relative path on the FTP server**\
+**format: `string` the format of the list reply (MLSD | LIST)**
+
+```{code-block} javascript
+async upload (username, path, format) {
+    ...
+}
+```
+
+### rename
+
+**Name: `rename`**\
+**Returns: `boolean`**
+
+The rename function takes 4 arguments when being called from jsftpd. It must return `true` on success or `false` on any error handling the file rename.
+
+**username: `string` the current user**\
+**path: `string` relative path on the FTP server**\
+**fromName: `string` the current file that needs to be renamed**
+**newName: `string` the new name of the file**
+
+```{code-block} javascript
+async upload (username, path, fromName, newName) {
+    ...
+}
+```

docs/options.md

@@ -24,10 +24,7 @@ To get an FTP server running quickly, the below code will get you started by all
 ```
 const { ftpd } = require('jsftpd')
 
-const server = new ftpd({cnf: {username: 'john', password: 'doe'})
-
-server.on('log', console.log)
-server.on('error', console.error)
+const server = new ftpd({cnf: {username: 'john', password: 'doe', basefolder: '/tmp'})
 
 server.start()
 ```
@@ -38,4 +35,5 @@ The full documentation of the project is available [here](https://jsftpd.readthe
 
 The ftpd instance takes an object with two properties that allows for configuring the new instance.
 - `tls` property object. Takes any configuration option as per node.js tls.createServer [options](https://nodejs.org/api/tls.html#tlscreateserveroptions-secureconnectionlistener)
-- `cnf` property object. Takes jsftpd specific configuration items. See full documentation [here](https://jsftpd.readthedocs.io/en/latest/)
+- `cnf` property object. Takes jsftpd specific configuration items. See full documentation [here](https://jsftpd.readthedocs.io/en/latest/options.html#cnf)
+- `hdl` property object. Takes handler functions for specific FTP commands. See full documentation [here](https://jsftpd.readthedocs.io/en/latest/options.html#hdl)