55 lines
2.1 KiB
Markdown
55 lines
2.1 KiB
Markdown
## Application structure
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Now, that we have built all the pieces we need, it is time to integrate them into the application. Let us exit the `/x` director go back at the root of the SDK directory.
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```bash
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// At root level of directory
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cd app
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```
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We are ready to create our simple governance application!
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*Note: You can check the full file (with comments!) [here](link)*
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The `app.go` file is the main file that defines your application. In it, you will declare all the modules you need, their keepers, handlers, stores, etc. Let us take a look at each section of this file to see how the application is constructed.
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Secondly, we need to define the name of our application.
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```go
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const (
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appName = "SimpleGovApp"
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)
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```
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Then, let us define the structure of our application.
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```go
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// Extended ABCI application
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type SimpleGovApp struct {
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*bam.BaseApp
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cdc *wire.Codec
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// keys to access the substores
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capKeyMainStore *sdk.KVStoreKey
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capKeyAccountStore *sdk.KVStoreKey
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capKeyStakingStore *sdk.KVStoreKey
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capKeySimpleGovStore *sdk.KVStoreKey
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// keepers
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feeCollectionKeeper auth.FeeCollectionKeeper
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coinKeeper bank.Keeper
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stakeKeeper simplestake.Keeper
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simpleGovKeeper simpleGov.Keeper
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// Manage getting and setting accounts
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accountMapper auth.AccountMapper
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}
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```
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- Each application builds on top of the `BaseApp` template, hence the pointer.
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- `cdc` is the codec used in our application.
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- Then come the keys to the stores we need in our application. For our simple governance app, we need 3 stores + the main store.
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- Then come the keepers and mappers.
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Let us do a quick reminder so that it is clear why we need these stores and keepers. Our application is primarily based on the `simple_governance` module. However, we have established in section [Keepers for our app](module-keeper.md) that our module needs access to two other modules: the `bank` module and the `stake` module. We also need the `auth` module for basic account functionalities. Finally, we need access to the main multistore to declare the stores of each of the module we use. |