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Description:

cstarmigrate 1.0.0rc2

Cassandra schema migration tool, a fork of cassandra-migrate.

Installation
Run python -m pip install cstar-migrate.

Reasoning
Unlike other available tools, this one:

Written in Python for easy installation
Does not require cqlsh, just the Cassandra Python driver
Supports baselining existing database to given versions
Supports partial advancement
Supports locking for concurrent instances using Lightweight Transactions
Verifies stored migrations against configured migrations
Stores content, checksum, date and state of every migration
Supports deploying with different keyspace configurations for different environments
Supports cql and python scripts migrations

Configuration
Databases are configured through YAML files. For example:
keyspace: cstar
profiles:
prod:
replication:
class: SimpleStrategy
replication_factor: 3
migrations_path: ./migrations
Where the migrations folder (relative to the config file). contains
.cql or .py files. The files are loaded in lexical order.
The default convention is to name them in the form: 001_my_migration.{cql | py}.
A custom naming scheme can be specified with the new_migration_name option.
For example
# Default migration names
new_migration_name: "{next_version:03d}_{desc}"

# Date-based migration names
new_migration_name: "{date:YYYYMMDDHHmmss}_{desc}"

# Custom initial migration content for cql scripts
new_cql_migration_text: |
/* Cassandra migration for keyspace {keyspace}.
Version {next_version} - {date}

{full_desc} */

# Custom initial migration content for python scripts
new_python_migration_text: |
# Cassandra migration for keyspace {keyspace}.
# Version {next_version} - {date}
# {full_desc} */

def execute(session, **kwargs):
"""
Main method for your migration. Do not rename this method.

Raise an exception of any kind to abort the migration.
"""

print("Cassandra session: ", session)
new_migration_name is a new-style Python format string, which can use the
following parameters:

next_version: Number of the newly generated migration (as an int).
desc: filename-clean description of the migration, as specified
by the user.
full_desc: unmodified description, possibly containing special characters.
date: current date in UTC. Pay attention to the choice of formatting,
otherwise you might include spaces in the file name. The above example should
be a good starting point.
keyspace: name of the configured keyspace.

The format string should not contain the .cql or .py extensions, as it they
added automatically.
new_cql_migraton_text defines the initial content of CQL migration files.
new_python_migraton_text defines the initial content of Python migration
files.

Profiles
Profiles can be defined in the configuration file. They can configure
the replication and durable_writes parameters for
CREATE KEYSPACE. A default dev profile is implicitly defined
using a replication factor of 1.

Usage
Common parameters:
-H HOSTS, --hosts HOSTS
Comma-separated list of contact points
-p PORT, --port PORT
Connection port
-u USER, --user USER
Connection username
-P PASSWORD, --password PASSWORD
Connection password
-c CONFIG_FILE, --config-file CONFIG_FILE
Path to configuration file
-l PROTOCOL_VERSION, --protocol-version PROTOCOL_VERSION
Connection protocol version
-m PROFILE, --profile PROFILE
Name of keyspace profile to use
-s SSL_CERT, --ssl-cert SSL_CERT
File path of .pem or .crt containing certificate of
the cassandra host you are connecting to (or the
certificate of the CA that signed the host
certificate). If this option is provided, cassandra-
migrate will use ssl to connect to the cluster. If
this option is not provided, the -k and -t options
will be ignored.
-k SSL_CLIENT_PRIVATE_KEY, --ssl-client-private-key SSL_CLIENT_PRIVATE_KEY
File path of the .key file containing the private key
of the host on which the cstar-migrate command is
run. This option must be used in conjuction with the
-t option. This option is ignored unless the -s option
is provided.
-t SSL_CLIENT_CERT, --ssl-client-cert SSL_CLIENT_CERT
File path of the .crt file containing the public
certificate of the host on which the cstar-migrate
command is run. This certificate (or the CA that
signed it) must be trusted by the cassandra host that
migrations are run against. This option must be used
in conjuction with the -k option. This option is
ignored unless the -s option is provided.
-y, --assume-yes
Automatically answer "yes" for all questions

migrate
Advances a database to the latest (or chosen) version of migrations.
Creates the keyspace and migrations table if necessary.
Migrate will refuse to run if a previous attempt failed. To override
that after cleaning up any leftovers (as Cassandra has no DDL
transactions), use the --force option.
Examples:
# Migrate to the latest database version using the default configuration file,
# connecting to Cassandra in the local machine
cstar-migrate -H 127.0.0.1 migrate

# Migrate to version 2 using a specific config file
cstar-migrate -c mydb.yml migrate 2

# Migrate to a version by name
cstar-migrate migrate 002_my_changes.cql

# Force migration after a failure
cstar-migrate migrate 2 --force

reset
Reset the database by dropping an existing keyspace, then running a migration.
Examples:
# Reset the database to the latest version
cstar-migrate reset

# Reset the database to a specifis version
cstar-migrate reset 3

clear
Clear the database by dropping an existing keyspace.
Example:
# Clear the database
cstar-migrate clear

baseline
Advance an existing database version without actually running the
migrations.
Useful for starting to manage a pre-existing database without recreating
it from scratch.
Examples:
# Baseline the existing database to the latest version
cstar-migrate baseline

# Baseline the existing database to a specific version
cstar-migrate baseline 5

status
Print the current status of the database.
Example:
cstar-migrate status

generate
Generate a new migration file with the appropriate name and a basic header
template, in the configured migrations_path.
When running the command interactively, the file will be opened by the default
editor. The newly-generated file name will be printed to stdout.
To generate a Python script, specify the --python option.
See the configuration section for details on migration naming.
Examples:
cstar-migrate generate "My migration description"

cstar-migrate generate "My migration description" --python