14 / 20Module 1: A Rell backend with FT4 accounts

Add modules to your dapp

Start applying this by splitting your code into smaller modules. Create a folder at Tic_tac_toe_Rell/src/tic_tac_toe and add a module.rell file to it:

src/news_feed/module.rell

module;

Then add a file at src/tic_tac_toe/entities.rell and move your entity definitions there.

src/main/entities.rell

entity game {    created_by: account;    created_at: timestamp = get_last_block_time();    mutable player2_account_rowid: rowid = rowid(0);    mutable last_step_by: rowid;    mutable last_step_at: timestamp = get_last_block_time();    mutable winner: rowid = rowid(0);    mutable status: game_status = game_status.created;    mutable slot_1: slot_states = slot_states.free;    mutable slot_2: slot_states = slot_states.free;    mutable slot_3: slot_states = slot_states.free;    mutable slot_4: slot_states = slot_states.free;    mutable slot_5: slot_states = slot_states.free;    mutable slot_6: slot_states = slot_states.free;    mutable slot_7: slot_states = slot_states.free;    mutable slot_8: slot_states = slot_states.free;    mutable slot_9: slot_states = slot_states.free;}

Move the import of the account entity from the ft4-library into module.rell as well. Placing it there gives every file in the module access to it.

src/news_feed/module.rell

module;import lib.ft4.accounts.{ account: account };import ft4_auth: lib.ft4.auth;

Next, add a file in the src/test/tic_tac_toe folder and declare it as a module, which creates a new module called module:

src/test/tic_tac_toe/module.rell

@test module;import tic_tac_toe.{ game, game_status, slot_states };import tic_tac_toe.external.{ create_game, get_games_by_status, join_game, make_move, get_game_by_id };import lib.ft4.accounts.{ account: account, auth_descriptor };import lib.ft4.core.accounts.strategies.open.{ ras_open };import lib.ft4.test.core. { create_auth_descriptor, ft_auth_operation_for };import lib.ft4.external.accounts.strategies.{ register_account };

To switch your dapp's entry point between the main module and the development module, change the module: tag in the blockchains definition of your chromia.yml file:

chromia.yml

blockchains:  tic_tac_toe:    module: main    moduleArgs:        lib.ft4.core.admin:          admin_pubkey: x"023BEE5A479CE5AF31F6F64EDE7BEAD394E92E4D973E1727782DB577A55E878563" # It can be completely random for learning purposes.compile:  rellVersion: 0.14.9database:  schema: schema_tic_tac_toetest:  modules:    - test.tic_tac_toe  moduleArgs:      lib.ft4.core.admin:        admin_pubkey: x"023BEE5A479CE5AF31F6F64EDE7BEAD394E92E4D973E1727782DB577A55E878563" # It can be completely random for learning purposes.libs:  ft4:    registry: https://gitlab.com/chromaway/ft4-lib.git    path: rell/src/lib/ft4    tagOrBranch: v1.2.0r    rid: x"E96915FD7C9A5DD4E183D86F4A5B4BB5083A7CC1EDEB1465EDFFC926E67C93F6"    insecure: false  iccf:    registry: https://gitlab.com/chromaway/core/directory-chain    path: src/lib/iccf    tagOrBranch: 1.87.0    rid: x"9C359787B75927733034EA1CEE74EEC8829D2907E4FC94790B5E9ABE4396575D"    insecure: false

Your project is now organized with Rell modules. The file structure should look similar to this:

text

├── main.rell├── tic_tac_toe│   ├── auth.rell│   ├── entities.rell│   ├── enums.rell│   ├── functions.rell│   ├── mappers.rell│   ├── module.rell│   ├── utils.rell│   ├── require.rell│   └── external│    	├── module.rell│    	├── operations.rell│    	├── queries.rell└── test/tic_tac_toe    ├── create_account_test.rell    ├── create_full_game.rell    ├── create_game_test.rell       ├── helpers.rell    ├── join_game_test.rell    ├── make_move_test.rell    └── module.rell

Written for this site from Chromia’s public course. Code samples are the course’s own.