Migrations¶

Henson-Database offers support for Alembic migrations. To enable them, install Henson-Database with the migrations extra:

$ python -m pip install Henson-Database[migrations]

This enables the following commands through the db namespace:

$ henson --app APP_PATH db --help

henson –app APP_PATH db¶

usage: henson --app APP_PATH db [-h]
                                    {branches,current,downgrade,edit,generate,heads,history,init,merge,revision,show,stamp,upgrade}
                                    ...

-h, --help¶: show this help message and exit

henson –app APP_PATH db branches¶

Show current branch points.

usage: henson --app APP_PATH db branches [-h] [--verbose]

-h, --help¶: show this help message and exit

--verbose, -v¶: verbose mode

henson –app APP_PATH db current¶

Display the current revision for a database.

usage: henson --app APP_PATH db current [-h] [--verbose]

-h, --help¶: show this help message and exit

--verbose, -v¶: verbose mode

henson –app APP_PATH db downgrade¶

Revert to a previous version.

usage: henson --app APP_PATH db downgrade [-h] [-s] [-t TAG] [revision]

revision¶: revision identifier

-h, --help¶: show this help message and exit

-s, --sql¶: don’t emit SQL to database - dump to standard output/file instead

-t <tag>, --tag <tag>¶: arbitrary ‘tag’ name - can be used by custom env.py scripts

henson –app APP_PATH db edit¶

Edit revision script(s) using $EDITOR.

usage: henson --app APP_PATH db edit [-h] rev

rev¶: None

-h, --help¶: show this help message and exit

henson –app APP_PATH db generate¶

Generate a revision (alias for ‘revision –autogenerate’).

usage: henson --app APP_PATH db generate [-h] [-m MESSAGE] [--sql]
                                             [--head HEAD] [--splice]
                                             [-b BRANCH_LABEL] [-v VERSION_PATH]
                                             [-r REV_ID] [-d DEPENDS_ON]

-h, --help¶: show this help message and exit

-m <message>, --message <message>¶: message string to use with ‘revision’

--sql¶: don’t emit SQL to database - dump to standard output/file instead

--head <head>¶: specify head revision or <branchname>@head to base new revision on

--splice¶: allow a non-head revision as the ‘head’ to splice onto

-b <branch_label>, --branch-label <branch_label>¶: specify a branch label to apply to the new revision

-v <version_path>, --version-path <version_path>¶: specify specific path from config for version file

-r <rev_id>, --rev-id <rev_id>¶: specify a hardcoded revision id instead of generating one

-d <depends_on>, --depends-on <depends_on>¶: specify one or more revision identifiers which this revision should depend on

henson –app APP_PATH db heads¶

Show current available heads in the script directory.

usage: henson --app APP_PATH db heads [-h] [-r] [--verbose]

-h, --help¶: show this help message and exit

-r, --resolve-dependencies¶: treat dependency versions as down revisions

--verbose, -v¶: verbose mode

henson –app APP_PATH db history¶

List changeset scripts in chronological order.

usage: henson --app APP_PATH db history [-h] [-r REV_RANGE] [--verbose]

-h, --help¶: show this help message and exit

-r <rev_range>, --rev-range <rev_range>¶: specify a revision range; format is [start]:[end]

--verbose, -v¶: verbose mode

henson –app APP_PATH db init¶

Initialize a new scripts directory.

usage: henson --app APP_PATH db init [-h] [directory]

directory¶: location of scripts directory

-h, --help¶: show this help message and exit

henson –app APP_PATH db merge¶

Merge two revisions together. Creates a new migration file.

usage: henson --app APP_PATH db merge [-h] [-m MESSAGE] [-b BRANCH_LABEL]
                                          [-r REV_ID]
                                          revisions

revisions¶: one or more revisions, or ‘heads’ for all heads

-h, --help¶: show this help message and exit

-m <message>, --message <message>¶: message string to use with ‘revision’

-b <branch_label>, --branch-label <branch_label>¶: specify a branch apply to the new revision

-r <rev_id>, --rev-id <rev_id>¶: specify a hardcoded revision id instead of generating one

henson –app APP_PATH db revision¶

Create a new revision file.

usage: henson --app APP_PATH db revision [-h] [-m MESSAGE] [-a] [--sql]
                                             [--head HEAD] [--splice]
                                             [-b BRANCH_LABEL] [-v VERSION_PATH]
                                             [-r REV_ID] [-d DEPENDS_ON]

-h, --help¶: show this help message and exit

-m <message>, --message <message>¶: message string to use with ‘revision’

-a, --autogenerate¶: populate revision script with candidate migration operations, based on comparison of database to model

--sql¶: don’t emit SQL to database - dump to standard output/file instead

--head <head>¶: specify head revision or <branchname>@head to base new revision on

--splice¶: allow a non-head revision as the ‘head’ to splice onto

-b <branch_label>, --branch-label <branch_label>¶: specify a branch label to apply to the new revision

-v <version_path>, --version-path <version_path>¶: specify specific path from config for version file

-r <rev_id>, --rev-id <rev_id>¶: specify a hardcoded revision id instead of generating one

-d <depends_on>, --depends-on <depends_on>¶: specify one or more revision identifiers which this revision should depend on

henson –app APP_PATH db show¶

Show the revision(s) denoted by the given symbol.

usage: henson --app APP_PATH db show [-h] rev

rev¶: None

-h, --help¶: show this help message and exit

henson –app APP_PATH db stamp¶

‘stamp’ the revision table with the given revision; don’t run any migrations.

usage: henson --app APP_PATH db stamp [-h] [-s] [-t TAG] revision

revision¶: revision identifier

-h, --help¶: show this help message and exit

-s, --sql¶: don’t emit SQL to database - dump to standard output/file instead

-t <tag>, --tag <tag>¶: arbitrary ‘tag’ name - can be used by custom env.py scripts

henson –app APP_PATH db upgrade¶

Upgrade to a later version.

usage: henson --app APP_PATH db upgrade [-h] [-s] [-t TAG] [revision]

revision¶: revision identifier

-h, --help¶: show this help message and exit

-s, --sql¶: don’t emit SQL to database - dump to standard output/file instead

-t <tag>, --tag <tag>¶: arbitrary ‘tag’ name - can be used by custom env.py scripts