[#184]: session token keywords moved to separate repo; session token

tests slightly refactored

Signed-off-by: anastasia prasolova <anastasia@nspcc.ru>

robot/resources/lib/python_keywords/session_token.py

@@ -0,0 +1,102 @@
+#!/usr/bin/python3
+
+"""
+    This module contains keywords for work with session token.
+"""
+
+import base64
+import json
+import os
+import uuid
+
+from neo3 import wallet
+from common import WALLET_PASS, ASSETS_DIR
+from cli_helpers import _cmd_run
+import json_transformers
+
+from robot.api.deco import keyword
+from robot.api import logger
+
+ROBOT_AUTO_KEYWORDS = False
+
+# path to neofs-cli executable
+NEOFS_CLI_EXEC = os.getenv('NEOFS_CLI_EXEC', 'neofs-cli')
+
+
+@keyword('Generate Session Token')
+def generate_session_token(owner: str, session_wallet: str, cid: str='') -> str:
+    """
+        This function generates session token for ContainerSessionContext
+        and writes it to the file. It is able to prepare session token file
+        for a specific container (<cid>) or for every container (adds
+        "wildcard" field).
+        Args:
+            owner(str): wallet address of container owner
+            session_wallet(str): the path to wallet to which we grant the
+                        access via session token
+            cid(optional, str): container ID of the container; if absent,
+                        we assume the session token is generated for any
+                        container
+        Returns:
+            (str): the path to the generated session token file
+    """
+    file_path = f"{os.getcwd()}/{ASSETS_DIR}/{uuid.uuid4()}"
+
+    session_wlt_content = ''
+    with open(session_wallet) as fout:
+        session_wlt_content = json.load(fout)
+    session_wlt = wallet.Wallet.from_json(session_wlt_content, password="")
+    pub_key_64 = base64.b64encode(
+                        bytes.fromhex(
+                            str(session_wlt.accounts[0].public_key)
+                        )
+                    ).decode('utf-8')
+
+    session_token = {
+                    "body":{
+                        "id":f"{base64.b64encode(uuid.uuid4().bytes).decode('utf-8')}",
+                        "ownerID":{
+                            "value":f"{json_transformers.encode_for_json(owner)}"
+                        },
+                        "lifetime":{
+                            "exp":"100000000",
+                            "nbf":"0",
+                            "iat":"0"
+                        },
+                        "sessionKey":f"{pub_key_64}",
+                        "container":{
+                            "verb":"PUT",
+                            "wildcard": cid != '',
+                            **({ "containerID":
+                                    {"value":
+                                        f"{base64.b64encode(cid.encode('utf-8')).decode('utf-8')}"}
+                                } if cid != '' else {}
+                            )
+                        }
+                    }
+                }
+
+    logger.info(f"Got this Session Token: {session_token}")
+    with open(file_path, 'w', encoding='utf-8') as session_token_file:
+        json.dump(session_token, session_token_file, ensure_ascii=False, indent=4)
+
+    return file_path
+
+
+@keyword ('Sign Session Token')
+def sign_session_token(session_token: str, wlt: str):
+    """
+        This function signs the session token by the given wallet.
+        Args:
+            session_token(str): the path to the session token file
+            wlt(str): the path to the signing wallet
+        Returns:
+            (str): the path to the signed token
+    """
+    signed_token = f"{os.getcwd()}/{ASSETS_DIR}/{uuid.uuid4()}"
+    cmd = (
+        f'{NEOFS_CLI_EXEC} util sign session-token --from {session_token} '
+        f'-w {wlt} --to {signed_token} --config {WALLET_PASS}'
+    )
+    _cmd_run(cmd)
+    return signed_token