cli: add live management commands

Add new parameters to the config file ogcli.json with the
following default values:
'local_live': '/var/www/html/ogrelive'
'server_live': 'https://opengnsys.soleta.eu/ogrelive'

Add command to install the files of a live system. Example:
ogcli install live --name ogrelive-6.1.0-26

Perform an update if live files are already present.

Add command to delete the files of a live system. Example:
ogcli delete live --name ogrelive-6.1.0-26

Update ogcli list live to show the lives in the server when
invoked with the --remote flag. Example:
ogcli list live --remote

3 files changed, 311 insertions, 3 deletions

diff --git a/cli/cli.py b/cli/cli.py
index 11d1521..0e34cd0 100644
--- a/cli/cli.py
+++ b/cli/cli.py
@@ -113,7 +113,7 @@ class OgCLI():
         elif parsed_args.item == 'servers':
             ret = OgServer.list_servers(self.rest)
         elif parsed_args.item == 'live':
-            ret = OgLive.list_live(self.rest)
+            ret = OgLive.list_live(self.rest, args[1:])
         return ret
 
     def set(self, args):
@@ -231,7 +231,7 @@ class OgCLI():
         return ret
 
     def delete(self, args):
-        choices = ['server', 'repo', 'center', 'room', 'client', 'folder']
+        choices = ['server', 'repo', 'center', 'room', 'client', 'folder', 'live']
         parser = argparse.ArgumentParser(prog='ogcli delete')
         parser.add_argument('delete_obj', choices=choices)
 
@@ -253,6 +253,8 @@ class OgCLI():
             ret = OgClient.delete_client(self.rest, args[1:])
         elif parsed_args.delete_obj == 'folder':
             ret = OgFolder.delete_folder(self.rest, args[1:])
+        elif parsed_args.delete_obj == 'live':
+            ret = OgLive.delete_live(self.rest, args[1:])
         return ret
 
     def add(self, args):
@@ -280,3 +282,19 @@ class OgCLI():
         elif parsed_args.add_obj == 'folder':
             ret = OgFolder.add_folder(self.rest, args[1:])
         return ret
+
+    def install(self, args):
+        choices = ['live']
+        parser = argparse.ArgumentParser(prog='ogcli install')
+        parser.add_argument('install_obj', choices=choices)
+
+        if not args:
+            print('Missing install subcommand', file=sys.stderr)
+            parser.print_help(file=sys.stderr)
+            return 1
+
+        parsed_args = parser.parse_args([args[0]])
+        ret = 0
+        if parsed_args.install_obj == 'live':
+            ret = OgLive.install_live(self.rest, args[1:])
+        return ret
diff --git a/cli/objects/live.py b/cli/objects/live.py
index 7a057bf..e7403b5 100644
--- a/cli/objects/live.py
+++ b/cli/objects/live.py
@@ -7,14 +7,284 @@
 
 import argparse
 
+from cli.config import cfg, OG_CLI_CFG_PATH
 from cli.utils import *
+import requests
+import shutil
+import sys
+import os
 
 class OgLive():
 
+    live_files = [
+        'initrd.img',
+        'vmlinuz',
+        'filesystem.squashfs',
+    ]
+    tmp_extension = '.tmp'
+
+    @staticmethod
+    def _get_local_live_dir():
+        local_live_dir = cfg.get('local_live', '/var/www/html/ogrelive')
+        if not local_live_dir:
+            print(f'Error: local_live not defined in {OG_CLI_CFG_PATH}')
+            return None
+
+        if not os.path.isdir(local_live_dir):
+            print(f'Warning: {local_live_dir} directoy does not exist, creating directory')
+            try:
+                os.makedirs(local_live_dir, exist_ok=True)
+            except OSError as e:
+                print(f'ERROR: Failed to create directory {local_live_dir}: {e}')
+                return None
+        return local_live_dir
+
+    @staticmethod
+    def _get_server_base_url():
+        server_live = cfg.get('server_live', 'https://opengnsys.soleta.eu/ogrelive')
+        if not server_live:
+            print(f'Error: server_live not defined in {OG_CLI_CFG_PATH}')
+            return None
+        return server_live
+
+    def _is_live_in_server(live_name):
+        server_live = OgLive._get_server_base_url()
+        target_url = f'{server_live}/{live_name}/{OgLive.live_files[0]}'
+        response = requests.head(target_url)
+        return response.status_code == 200
+
+    @staticmethod
+    def _delete_tmp_live_files(live_name):
+        local_live_dir = OgLive._get_local_live_dir()
+
+        if not local_live_dir:
+            return 1
+
+        folder_path = os.path.join(local_live_dir, live_name)
+
+        for file_name in os.listdir(folder_path):
+            if not file_name.endswith(OgLive.tmp_extension):
+                continue
+            target_file = os.path.join(folder_path, file_name)
+            try:
+                os.remove(target_file)
+            except OSError as e:
+                print(f'ERROR: Failed to delete temporary file {target_file}: {e}')
+                return 1
+        return 0
+
+    @staticmethod
+    def _download_from_server(file_path, local_extension):
+        live_file = os.path.basename(file_path)
+
+        server_live = OgLive._get_server_base_url()
+        if not server_live:
+            return 1
+        file_url = f'{server_live}/{file_path}'
+
+        local_live_dir = OgLive._get_local_live_dir()
+
+        if not local_live_dir:
+            return 1
+
+        local_path = os.path.join(local_live_dir, file_path)
+        if local_extension:
+            local_path += local_extension
+
+        try:
+            response = requests.get(file_url, stream=True, timeout=(5, None))
+        except requests.exceptions.RequestException as e:
+            print(f'Request failed for {file_url}: {e}')
+            return 1
+
+        err = 0
+        if response.status_code == 200:
+            try:
+                with open(local_path, 'wb') as f:
+                    for chunk in response.iter_content(chunk_size=8192):
+                        if chunk:
+                            f.write(chunk)
+            except OSError as e:
+                print(f'File system error occurred: {e}')
+                err = 1
+        else:
+            print(f'ERROR: Failed to download {live_file}. Status code: {response.status_code}')
+            err = 1
+
+        if err:
+            try:
+                if os.path.exists(local_path):
+                    os.remove(local_path)
+            except OSError as e:
+                print(f'ERROR: Failed to delete file {live_file}: {e}')
+            return 1
+        return 0
+
     @staticmethod
-    def list_live(rest):
+    def list_live(rest, args):
+        parser = argparse.ArgumentParser(prog='ogcli list live')
+        parser.add_argument('--remote',
+                            action='store_true',
+                            help='(Optional) Obtain the list of the remote instead of the local lives')
+        parsed_args = parser.parse_args(args)
+
+        if parsed_args.remote:
+            local_live_dir = OgLive._get_local_live_dir()
+
+            if not local_live_dir:
+                return 1
+
+            download_err = OgLive._download_from_server('ogrelive.json',
+                                                        local_extension=OgLive.tmp_extension)
+            if download_err:
+                return 1
+
+            remote_json = os.path.join(local_live_dir, 'ogrelive.json')
+            remote_json_tmp = remote_json + OgLive.tmp_extension
+            try:
+                shutil.move(remote_json_tmp, remote_json)
+            except OSError as e:
+                print(f'ERROR: cannot move {remote_json_tmp} into {remote_json}: {e}')
+                return 1
+
+            try:
+                with open(remote_json, 'r') as json_file:
+                    remote_data = json_file.read()
+            except json.JSONDecodeError:
+                print(f'ERROR: Failed parse malformed JSON file {remote_json}')
+                return 1
+            except OSError as e:
+                print(f'ERROR: cannot open {remote_json}: {e}')
+                return 1
+
+            print_json(remote_data)
+            return 0
+
         res = rest.get('/oglive/list')
         if not res:
             return 1
         print_json(res.text)
         return 0
+
+    @staticmethod
+    def _is_same_checksum(file_path, checksum_path):
+        local_checksum = compute_md5(file_path)
+        try:
+            with open(checksum_path, 'r') as f:
+                remote_checksum = f.read().strip()
+        except (FileNotFoundError, PermissionError, OSError) as e:
+            print(f'ERROR: Cannot read checksum file for {live_file}: {e}')
+            return False
+        return local_checksum == remote_checksum
+
+    @staticmethod
+    def install_live(rest, args):
+        parser = argparse.ArgumentParser(prog='ogcli install live')
+        parser.add_argument('--name',
+                            nargs='?',
+                            required=True,
+                            help='Name of the center')
+        parsed_args = parser.parse_args(args)
+
+        live_name = parsed_args.name
+
+        local_live_dir = OgLive._get_local_live_dir()
+
+        if not local_live_dir:
+            return 1
+
+        if not OgLive._is_live_in_server(live_name):
+            print(f'{live_name} is not available on the server, it cannot be installed')
+            return 1
+
+        local_dir = os.path.join(local_live_dir, live_name)
+        if os.path.exists(local_dir):
+            print(f'{live_name} already exists, checking for updates...')
+        try:
+            os.makedirs(local_dir, exist_ok=True)
+        except OSError as e:
+            print(f'ERROR: Failed to create directory {local_dir}: {e}')
+            return 1
+
+        for live_file in OgLive.live_files:
+            download_err = OgLive._download_from_server(os.path.join(live_name,
+                                                        live_file + '.full.sum'),
+                                                        local_extension=OgLive.tmp_extension)
+            if download_err:
+                return download_err
+
+            file_path = os.path.join(local_dir, live_file)
+            file_path_tmp = file_path + OgLive.tmp_extension
+            checksum_path_tmp = file_path + '.full.sum' + OgLive.tmp_extension
+
+            is_first_install = not os.path.exists(file_path)
+            if is_first_install:
+                print(f'Downloading {live_file}...')
+            else:
+                requires_update = not OgLive._is_same_checksum(file_path, checksum_path_tmp)
+                if not requires_update:
+                    print(f'{live_file} is up-to-date, skipping')
+                    continue
+
+                print(f'Updating {live_file}...')
+            download_err = OgLive._download_from_server(os.path.join(live_name,
+                                                        live_file),
+                                                        local_extension=OgLive.tmp_extension)
+            if download_err:
+                return download_err
+
+            if not OgLive._is_same_checksum(file_path_tmp, checksum_path_tmp):
+                print(f'ERROR: Checksum mismatch for {live_file}')
+                OgLive._delete_tmp_live_files(live_name)
+                return 1
+
+            print(f'Checksum is OK for {live_file}')
+            try:
+                shutil.move(file_path_tmp, file_path)
+            except OSError as e:
+                print(f'ERROR: cannot move {src_file} into {target_file}: {e}')
+                OgLive._delete_tmp_live_files(live_name)
+                return 1
+
+        OgLive._delete_tmp_live_files(live_name)
+
+        payload = {'name': live_name}
+        res = rest.post('/oglive/add', payload=payload)
+
+        if not res:
+            return 1
+        return 0
+
+    @staticmethod
+    def delete_live(rest, args):
+        parser = argparse.ArgumentParser(prog='ogcli delete live')
+        parser.add_argument('--name',
+                            nargs='?',
+                            required=True,
+                            help='Name of the center')
+        parsed_args = parser.parse_args(args)
+        live_name = parsed_args.name
+
+        payload = {'name': live_name}
+        res = rest.post('/oglive/delete', payload=payload)
+
+        if not res:
+            return 1
+
+        local_live_dir = OgLive._get_local_live_dir()
+
+        if not local_live_dir:
+            return 1
+
+        local_dir = os.path.join(local_live_dir, live_name)
+
+        if os.path.exists(local_dir):
+            try:
+                shutil.rmtree(local_dir)
+            except OSError as e:
+                print(f'Error deleting directory {local_dir}: {e}')
+                return 1
+        else:
+            print(f'Error: no directory found for {live_name}')
+
+        return 0
diff --git a/cli/utils.py b/cli/utils.py
index 3825583..380bd5b 100644
--- a/cli/utils.py
+++ b/cli/utils.py
@@ -8,7 +8,9 @@
 import unicodedata
 import json
 import ipaddress
+import hashlib
 import re
+import os
 
 def scope_lookup(scope_id, scope_type, d):
     if scope_id == d.get('id') and scope_type == d.get('type'):
@@ -69,3 +71,21 @@ def check_mac_address(addr):
 def remove_accents(text):
     normalized_text = unicodedata.normalize('NFD', text)
     return ''.join(c for c in normalized_text if unicodedata.category(c) != 'Mn')
+
+def compute_md5(path, bs=2**20):
+    if not os.path.exists(path):
+        print(f"Failed to calculate checksum, image file {path} does not exist")
+        return None
+
+    m = hashlib.md5()
+    try:
+        with open(path, 'rb') as f:
+            while True:
+                buf = f.read(bs)
+                if not buf:
+                    break
+                m.update(buf)
+    except Exception as e:
+        print(f'Failed to calculate checksum for {path}: {e}')
+        return None
+    return m.hexdigest()