tubearchivist/backend/appsettings/src/index_setup.py

380 lines
12 KiB
Python

"""
functionality:
- setup elastic index at first start
- verify and update index mapping and settings if needed
- backup and restore metadata
"""
from enum import Enum, auto
from appsettings.src.backup import ElasticBackup
from appsettings.src.config import AppConfig
from appsettings.src.snapshot import ElasticSnapshot
from common.src.es_connect import ElasticWrap
from common.src.helper import get_mapping
from deepdiff import DeepDiff
from django.conf import settings
class MappingAction(Enum):
"""index action options"""
NOOP = auto()
PUT_MAPPING = auto()
REINDEX = auto()
class ElasticIndex:
"""interact with a single index"""
REINDEX_KEYS = {
"type",
"analyzer",
"search_analyzer",
"normalizer",
"index",
"doc_values",
"norms",
"ignore_above",
"enabled",
"format",
}
def __init__(self, index_name, expected_map=False, expected_set=False):
self.index_name = index_name
self.expected_map = expected_map
self.expected_set = expected_set
self.exists, self.details = self.index_exists()
@property
def index_namespace(self) -> str:
"""namespaced index"""
return f"ta_{self.index_name}"
def index_exists(self):
"""check if index already exists and return mapping if it does"""
response, status_code = ElasticWrap(self.index_namespace).get()
exists = status_code == 200
index_key = f"{self.index_namespace}"
current_version = self.get_current_version()
if current_version:
index_key += f"_v{current_version}"
details = response.get(index_key, False)
return exists, details
def get_current_version(self) -> None | int:
"""get current version from aliases of index"""
response, _ = ElasticWrap(f"{self.index_namespace}/_alias").get()
if not response:
raise ValueError("failed to fetch aliases: ", response)
alias_name = list(response.keys())
if not alias_name:
return None
version_str = alias_name[0].lstrip(f"{self.index_namespace}_v")
if not version_str:
# is initial version
return None
if not version_str.isdigit():
raise ValueError("unexpected version_str: ", version_str)
return int(version_str)
def validate(self) -> tuple[MappingAction, set[str]]:
"""
check if all expected mappings and settings match
returns True when rebuild is needed
"""
mapping_diff = self._get_mapping_diff()
removed_fields = self._get_fields_to_delete(diff=mapping_diff)
if self.expected_set:
settings_diff = self._validate_settings()
if settings_diff:
# treat settings diff as full reindex
return MappingAction.REINDEX, removed_fields
if self.expected_map or self.expected_map == {}:
action = self._classify_mapping_diff(diff=mapping_diff)
return action, removed_fields
return MappingAction.NOOP, removed_fields
def _validate_settings(self):
"""check if all settings are as expected"""
now_set = self.details["settings"]["index"]
for key, value in self.expected_set.items():
if key not in now_set.keys():
print(key, value)
return True
if not value == now_set[key]:
print(key, value)
return True
return False
def _get_mapping_diff(self) -> DeepDiff:
"""check if all mappings are as expected"""
now_map = self.details.get("mappings", {}).get("properties", {})
diff = DeepDiff(
now_map,
self.expected_map,
ignore_order=True,
report_repetition=True,
view="tree",
)
if diff:
print(f"[{self.index_namespace}] detected mapping change")
if settings.DEBUG:
print(f"[{self.index_namespace}] mapping change: {diff}")
return diff
def _classify_mapping_diff(self, diff: DeepDiff) -> MappingAction:
"""use diff to detect what to do"""
if not diff:
return MappingAction.NOOP
if diff.get("type_changes"):
# always incompatible, needs reindex
return MappingAction.REINDEX
added = diff.get("dictionary_item_added", [])
has_additions = bool(added)
for item in diff.get("values_changed", []):
path = item.path(output_format="list")
if not path:
continue
if path[-1] in self.REINDEX_KEYS:
return MappingAction.REINDEX
# compatible addition
has_additions = True
if has_additions:
return MappingAction.PUT_MAPPING
return MappingAction.NOOP
def _get_fields_to_delete(self, diff: DeepDiff) -> set[str]:
"""fields to remove during next reindex"""
removed_fields = set()
for item in diff.get("dictionary_item_removed", []):
value = item.t1 or {}
is_field_definition = "type" in value or "properties" in value
if not is_field_definition:
continue
path = item.path(output_format="list")
removed_fields.add(".".join(path))
return removed_fields
def rebuild_index(self, removed_fields: set[str]):
"""rebuild with new mapping"""
print(f"[{self.index_namespace}] applying new mappings to index")
current_version = self.get_current_version()
new_version = current_version + 1 if current_version else 2
self.create_blank(new_version=new_version)
self.reindex(new_version=new_version, removed_fields=removed_fields)
self.delete_index(by_version=current_version)
self.create_alias(new_version=new_version, old_version=current_version)
def delete_index(self, by_version: int | None):
"""delete index passed as argument"""
path = self.index_namespace
if by_version is not None:
path += f"_v{by_version}"
response, status_code = ElasticWrap(path).delete()
print(f"{status_code}: {response}")
def create_blank(self, new_version: int | None = None):
"""create blank"""
path = self.index_namespace
if new_version is not None:
path += f"_v{new_version}"
data = {}
if self.expected_set:
data.update({"settings": self.expected_set})
if self.expected_map or self.expected_map == {}:
data.update({"mappings": {"properties": self.expected_map}})
if self.index_name == "config":
# no indexing for config
data["mappings"]["dynamic"] = False
print(f"[{path}] create new blank index")
if settings.DEBUG:
print(f"[{path}] creat new blank index with data: {data}")
response, status_code = ElasticWrap(path).put(data)
if status_code not in [200, 201]:
print(f"{status_code}: {response}")
raise ValueError(f"create blank index {path} failed")
def reindex(self, new_version: int, removed_fields: set[str]):
"""reindex to versioned new index after creating"""
source = self.index_namespace
dest = f"{self.index_namespace}_v{new_version}"
data: dict = {"source": {"index": source}, "dest": {"index": dest}}
if removed_fields:
script = "\n".join(
f"ctx._source.remove('{i}');" for i in removed_fields
)
data["script"] = {"lang": "painless", "source": script}
print(f"[{self.index_namespace}] reindex from {source} to {dest}")
if settings.DEBUG:
print(f"send data: {data}")
path = "_reindex?refresh=true"
response, status_code = ElasticWrap(path).post(data=data)
if status_code not in [200, 201]:
print(f"{status_code}: {response}")
raise ValueError("reindex failed failed")
def create_alias(self, new_version: int, old_version: int | None = None):
"""create aliast for moved index"""
data: dict = {
"actions": [
{
"add": {
"index": f"{self.index_namespace}_v{new_version}",
"alias": self.index_namespace,
"is_write_index": True,
},
},
]
}
if old_version:
data["actions"].append(
{
"remove": {
"index": f"{self.index_namespace}_v{old_version}",
"alias": self.index_namespace,
}
}
)
if settings.DEBUG:
print(f"create alias: {data}")
response, status_code = ElasticWrap("_alias").put(data=data)
if status_code not in [200, 201]:
print(f"{status_code}: {response}")
raise ValueError("alias update failed")
def mapping_update(self):
"""simple mapping update only, use migrations for defaults"""
current_version = self.get_current_version()
path = self.index_namespace
if current_version is not None:
path += f"_v{current_version}"
data = {"properties": self.expected_map}
print(f"[{path}] update mapping")
if settings.DEBUG:
print(f"[{path}] update mapping with data: {data}")
response, status_code = ElasticWrap(path).put(data)
if status_code not in [200, 201]:
print(f"{status_code}: {response}")
raise ValueError(f"create blank index {path} failed")
class ElasticIndexWrap:
"""interact with all index mapping and setup"""
def __init__(self):
self.index_config = get_mapping()
self.backup_run = False
def setup(self):
"""setup elastic index, run at startup"""
for index in self.index_config:
index_name, expected_map, expected_set = self._config_split(index)
handler = ElasticIndex(index_name, expected_map, expected_set)
if not handler.exists:
handler.create_blank()
continue
action, removed_fields = handler.validate()
if action == MappingAction.REINDEX:
self._check_backup()
handler.rebuild_index(removed_fields)
continue
if action == MappingAction.PUT_MAPPING:
handler.mapping_update()
# else all good
print(f"[ta_{index_name}] index status is as expected.")
def reset(self):
"""reset all indexes to blank"""
self.delete_all()
self.create_all_blank()
def delete_all(self):
"""delete all indexes"""
for index in self.index_config:
index_name, _, _ = self._config_split(index)
print(f"[ta_{index_name}] reset elastic index")
handler = ElasticIndex(index_name)
current_version = handler.get_current_version()
handler.delete_index(by_version=current_version)
def create_all_blank(self):
"""create all blank indexes"""
print("create all new indexes in elastic from template")
for index in self.index_config:
index_name, expected_map, expected_set = self._config_split(index)
handler = ElasticIndex(index_name, expected_map, expected_set)
handler.create_blank()
@staticmethod
def _config_split(index):
"""split index config keys"""
index_name = index["index_name"]
expected_map = index["expected_map"]
expected_set = index["expected_set"]
return index_name, expected_map, expected_set
def _check_backup(self):
"""create backup if needed"""
if self.backup_run:
return
try:
config = AppConfig().config
except ValueError:
# create defaults in ES if config not found
print("AppConfig not found, creating defaults...")
handler = AppConfig.__new__(AppConfig)
handler.sync_defaults()
config = AppConfig.CONFIG_DEFAULTS
if config["application"]["enable_snapshot"]:
# take snapshot if enabled
ElasticSnapshot().take_snapshot_now(wait=True)
else:
# fallback to json backup
ElasticBackup(reason="update").backup_all_indexes()
self.backup_run = True