def connect_to_couchdb_server(self):
"""
This function is used to connect to the couch DB server.
"""
while self.couchdb_instance is None:
self.couchdb_instance = couchdb.Server(str("http://{}/".format(self.couchdb_server_name)))
logging_to_console_and_syslog("Successfully connected to couchdb server {}."
.format(self.couchdb_server_name))
def yield_id_to_container_entries(self):
"""
This function is used to yield each row from id to container db and return it back to the caller one row at a time."
"""
if self.id_to_container_db is None:
logging_to_console_and_syslog("id_to_container_db is None.")
raise BaseException
for id in self.id_to_container_db:
yield (id, dict(self.id_to_container_db[id].items()))
def yield_database_handle_entries(self):
"""
This function is used to yield entries from the document database one at a time.
"""
if self.database_handle is None:
logging_to_console_and_syslog("database_handle is None.")
raise BaseException
for id in self.database_handle:
yield (id, dict(self.database_handle[id].items()))
def add_entry_into_id_to_container_database(self,
document_id,
container_id):
"""
This function is used to add/update a row in the id to container database.
"""
if self.id_to_container_db is None:
logging_to_console_and_syslog("id_to_container_db is None.")
raise BaseException
if document_id is None or container_id is None:
logging_to_console_and_syslog("document_id or container_id is None.")
return False
try:
document = self.id_to_container_db[document_id]
logging_to_console_and_syslog("Updating {},{} into the id_to_container_database."
.format(document_id, container_id))
document.update({document_id: container_id})
except:
logging_to_console_and_syslog("Adding {},{} into the id_to_container_database."
.format(document_id, container_id))
self.id_to_container_db[document_id] = {document_id: container_id}
return True
def delete_id_to_container_entry(self, document_id):
"""
This function is used to delete a row from the id to container database based upon the key (document id).
"""
if self.id_to_container_db is None:
logging_to_console_and_syslog("id_to_container_db is None.")
raise BaseException
if document_id in self.id_to_container_db:
logging_to_console_and_syslog("Deleting document_id {} "
"from id_to_container_db."
.format(document_id))
del self.id_to_container_db[document_id]
return True
return False
def delete_entry_from_master_database(self, document_id):
"""
This function is used to delete a row from the master database based upon the key (document id).
"""
if self.database_handle is None:
logging_to_console_and_syslog("database_handle is None.")
raise BaseException
if document_id in self.database_handle:
logging_to_console_and_syslog("Deleting document_id {} "
"from database_handle."
.format(document_id))
del self.database_handle[document_id]
return True
return False
def fetch_data_from_id_to_container_entry(self, document_id):
"""
This function returns a document value based upon the document identifier from the id to container database.
"""
document_value = None
if document_id is None:
return None
if self.id_to_container_db is None:
logging_to_console_and_syslog("id_to_container_db is None.")
raise BaseException
if document_id in self.id_to_container_db:
document_value = dict(self.id_to_container_db[document_id].items())
logging_to_console_and_syslog("Fetching key={}, value={} "
"from id_to_container_db."
.format(document_id,
document_value))
return document_value
def check_entry_in_master_database(self,document_id):
"""
This function returns a document value based upon the document identifier from the master database.
"""
document_value = None
if document_id is None:
return None
if self.database_handle is None:
logging_to_console_and_syslog("database_handle is None.")
raise BaseException
if document_id in self.database_handle:
document_value = dict(self.database_handle[document_id].items())
logging_to_console_and_syslog("Fetching key={}, value={} "
"from database_handle."
.format(document_id,
document_value))
return document_value
def fetch_data_from_master_database(self, document_id):
"""
This function is used to fetch a document from the document database based upon the passed in document identifier.
"""
if document_id is None:
return None
document_value = None
if self.database_handle is None:
logging_to_console_and_syslog("id_to_container_db is None.")
raise BaseException
if document_id in self.database_handle:
document_value = dict(self.database_handle[document_id].items())
logging_to_console_and_syslog("Fetching key={}, value={} "
"from master database_handle."
.format(document_id,
document_value))
return document_value
def create_id_to_container_database(self):
"""
This function is used to create id to container database in the server.
"""
if self.couchdb_instance is None:
logging_to_console_and_syslog("couchdb_instance is None.")
raise BaseException
if self.id_to_container_name in self.couchdb_instance:
logging_to_console_and_syslog("Found the database name {} in the server."
.format(self.id_to_container_name))
self.id_to_container_db = self.couchdb_instance[self.id_to_container_name]
else:
logging_to_console_and_syslog("Creating the database name {} in the server."
.format(self.id_to_container_name))
self.id_to_container_db = self.couchdb_instance.create(self.id_to_container_name)
def create_document_database_name_in_the_server(self):
"""
This function is used to create document database in the server.
"""
if self.couchdb_instance is None:
logging_to_console_and_syslog("couchdb_instance is None.")
raise BaseException
if self.database_name in self.couchdb_instance:
logging_to_console_and_syslog("Found the database name {} in the server."
.format(self.database_name))
self.database_handle = self.couchdb_instance[self.database_name]
else:
logging_to_console_and_syslog("Creating the database name {} in the server."
.format(self.database_name))
self.database_handle = self.couchdb_instance.create(self.database_name)
if self.database_handle is None:
raise BaseException
def add_entry_into_master_database(self, document):
"""
This function is used to add/update a row in the master database.
"""
if self.database_handle is None:
logging_to_console_and_syslog("database_handle is None.")
raise BaseException
if document is None or type(document) != dict:
logging_to_console_and_syslog("Invalid input parameters.")
return None
try:
#document = {'type': 'Person', 'name': 'John Doe'}
doc_id, doc_rev = self.database_handle.save(document)
logging_to_console_and_syslog("Creating a document {}, id={} into the master database."
.format(document, doc_id))
return doc_id
except:
return None
def read_environment_variables(self):
"""
This function sinks in the global environment variables.
"""
while self.couchdb_server_name is None or \
self.database_name is None or \
self.id_to_container_name is None:
self.couchdb_server_name = os.getenv("couchdb_server_key",
default=None)
self.database_name = os.getenv("database_name_key",
default=None)
self.id_to_container_name = os.getenv("id_to_container_name_key",
default=None)
logging_to_console_and_syslog("couchdb_server_name={}"
.format(self.couchdb_server_name))
logging_to_console_and_syslog("database_name={}"
.format(self.database_name))
logging_to_console_and_syslog("id_to_container_name={}"
.format(self.id_to_container_name))