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+# Static Deplyer
+
+A simple daemon help with extracting tar files to specific place
+and create a symbolic link to it, the tar files should be transferred
+to this daemon by http.
+
+## Caution
+
+No `data-form` or `x-www-urlencoded-form` supported, so the tar must be transferred
+just in POST body, ie: `curl --data-binary @file.tar.gz`.
+
+No authorization implemented, so a reverse proxy with auth is recommanded.
+
+Tar file with sub directories with be extracted as is, so do not contain parent
+directory when you create tar.
+
+## Usage
+
+```
+$ ./main.py --help
+usage: main.py [-h] --archive-dir ARCHIVE_DIR --extract-dir EXTRACT_DIR --symlink-path
+               SYMLINK_PATH [--keep-extract KEEP_EXTRACT] [--keep-archive KEEP_ARCHIVE]
+               --port PORT [--temp-dir TEMP_DIR]
+
+options:
+  -h, --help            show this help message and exit
+  --archive-dir ARCHIVE_DIR
+                        directory to save archives
+  --extract-dir EXTRACT_DIR
+                        directory to save extracted files
+  --symlink-path SYMLINK_PATH
+                        path of symlink which redirect to extracted archive
+  --keep-extract KEEP_EXTRACT
+                        Number of extracted archives to keep, 0 mean never vacuum
+  --keep-archive KEEP_ARCHIVE
+                        Number of archives to keep, 0 mean never vacuum
+  --port PORT           listen port on 127.0.0.1, no authorization implemented so only
+                        listen on 127.0.0.1 for safety
+  --temp-dir TEMP_DIR   path to save in-delivery archive
+```
+
+## Example
+
+First start the daemon.
+
+```
+$ ./main.py --port 8080 --archive-dir archive --extract-dir extracted --symlink-path serve
+INFO:root:Listening on 127.0.0.1:8080
+INFO:root:Archive saves under: archive
+INFO:root:Extract tar under: extracted
+INFO:root:Keep 8 archives at most
+INFO:root:Keep 4 extracted at most
+INFO:root:Symbolic link location: serve
+INFO:root:Temperory directory: /tmp
+INFO:root:Starting httpd...
+```
+
+Then create a tar and upload it to this daemon.
+
+**Note**: the tar shouldn't contain its parent directory, but `.` as parent
+is acceptable. Or you can follow [this step](https://stackoverflow.com/a/39530409)
+to create a more elegant tar.
+
+```
+$ mkdir tmp
+$ cd tmp
+$ echo 'Hello, world!' > index.html
+$ tar --gzip -cf ../tmp.tar.gz .
+$ tar -tf ../tmp.tar.gz
+./
+./index.html
+$ curl --data-binary @../tmp.tar.gz http://localhost:8080/
+Success
+```
+
+And the server side shows
+
+```
+...
+INFO:root:Starting httpd...
+INFO:FileManager:Temporarily save to /tmp/archive_2023-04-04T10:35:49.tar.gz
+INFO:FileManager:Moving saved archive to archive/archive_2023-04-04T10:35:49.tar.gz
+INFO:FileManager:Extracting to extracted/archive_2023-04-04T10:35:49
+INFO:FileManager:Recreating symlink point to extracted/archive_2023-04-04T10:35:49
+INFO:FileManager:Vacuuming archive, keep the 8 lastest
+INFO:FileManager:Vacuuming extract, keep the 4 lastest
+INFO:FileManager:Deploy success
+127.0.0.1 - - [04/Apr/2023 10:35:49] "POST / HTTP/1.1" 200 -
+```
+
+Finally the directory looks like (omit unrelated directories):
+
+```
+.
+├── archive
+│   └── archive_2023-04-04T10:35:49.tar.gz
+├── extracted
+│   └── archive_2023-04-04T10:35:49
+│       └── index.html
+└── serve -> extracted/archive_2023-04-04T10:35:49
+```
+
+## Use Case
+
+When you hold a static site and want to update its content easily,
+like just uploading a tar and automatically deployed.