Merge pull request Agoric#43 from cosmos/sunny/combine-stores

R4R: Combined three stores into one with Whois struct as value  Agoric#2

Author: sunnya97

Gopkg.lock

@@ -30,9 +30,7 @@ type nameServiceApp struct {
 
 	keyMain          *sdk.KVStoreKey
 	keyAccount       *sdk.KVStoreKey
-	keyNSnames       *sdk.KVStoreKey
-	keyNSowners      *sdk.KVStoreKey
-	keyNSprices      *sdk.KVStoreKey
+	keyNS            *sdk.KVStoreKey
 	keyFeeCollection *sdk.KVStoreKey
 	keyParams        *sdk.KVStoreKey
 	tkeyParams       *sdk.TransientStoreKey
@@ -60,9 +58,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 
 		keyMain:          sdk.NewKVStoreKey("main"),
 		keyAccount:       sdk.NewKVStoreKey("acc"),
-		keyNSnames:       sdk.NewKVStoreKey("ns_names"),
-		keyNSowners:      sdk.NewKVStoreKey("ns_owners"),
-		keyNSprices:      sdk.NewKVStoreKey("ns_prices"),
+		keyNS:            sdk.NewKVStoreKey("ns"),
 		keyFeeCollection: sdk.NewKVStoreKey("fee_collection"),
 		keyParams:        sdk.NewKVStoreKey("params"),
 		tkeyParams:       sdk.NewTransientStoreKey("transient_params"),
@@ -93,9 +89,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 	// It handles interactions with the namestore
 	app.nsKeeper = nameservice.NewKeeper(
 		app.bankKeeper,
-		app.keyNSnames,
-		app.keyNSowners,
-		app.keyNSprices,
+		app.keyNS,
 		app.cdc,
 	)
 
@@ -118,9 +112,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 	app.MountStores(
 		app.keyMain,
 		app.keyAccount,
-		app.keyNSnames,
-		app.keyNSowners,
-		app.keyNSprices,
+		app.keyNS,
 		app.keyFeeCollection,
 		app.keyParams,
 		app.tkeyParams,

app.go

@@ -39,7 +39,8 @@ Through the course of this tutorial you will create the following files that mak
         ├── handler.go
         ├── keeper.go
         ├── msgs.go
-        └── querier.go
+        ├── querier.go
+        └── types.go
 ```
 
 Start by creating a new git repository:
@@ -56,18 +57,19 @@ Then, just follow along! The first step describes the design of your application
 
 1. [Design](./app-design.md) the application.
 2. Begin the implementation of your application in [`./app.go`](./app-init.md).
-3. Start building your module with the [`Keeper`](./keeper.md).
-4. Define state transitions through [`Msgs` and `Handlers`](./msgs-handlers.md).
+3. Start building your module by defining some basic [`Types`](./types.md).
+4. Create the main core of the module using the [`Keeper`](./keeper.md).
+5. Define state transitions through [`Msgs` and `Handlers`](./msgs-handlers.md).
     * [`SetName`](./set-name.md)
     * [`BuyName`](./buy-name.md)
-5. Make views on your state machine with [`Queriers`](./queriers.md).
-6. Register your types in the encoding format using [`sdk.Codec`](./codec.md).
-7. Create [CLI interactions for your module](./cli.md).
-8. Create [HTTP routes for clients to access your nameservice](./rest.md)
-9. Import your module and [finish building your application](./app-complete.md)!
-10. Create the [`nsd` and `nscli` entry points](./entrypoint.md) to your application.
-11. Setup [dependency management using `dep`](./dep.md).
-12. [Build and run](./build-run.md) the example.
-13. [Run REST routes](./run-rest.md).
+6. Make views on your state machine with [`Queriers`](./queriers.md).
+7. Register your types in the encoding format using [`sdk.Codec`](./codec.md).
+8. Create [CLI interactions for your module](./cli.md).
+9. Create [HTTP routes for clients to access your nameservice](./rest.md)
+10. Import your module and [finish building your application](./app-complete.md)!
+11. Create the [`nsd` and `nscli` entry points](./entrypoint.md) to your application.
+12. Setup [dependency management using `dep`](./dep.md).
+13. [Build and run](./build-run.md) the example.
+14. [Run REST routes](./run-rest.md).
 
 ## [Click here](./app-design.md) to get started with the tutorial!

tutorial/README.md

@@ -42,9 +42,7 @@ type nameServiceApp struct {
 
 	keyMain          *sdk.KVStoreKey
 	keyAccount       *sdk.KVStoreKey
-	keyNSnames       *sdk.KVStoreKey
-	keyNSowners      *sdk.KVStoreKey
-	keyNSprices      *sdk.KVStoreKey
+	keyNS            *sdk.KVStoreKey
 	keyFeeCollection *sdk.KVStoreKey
 	keyParams        *sdk.KVStoreKey
 	tkeyParams       *sdk.TransientStoreKey
@@ -56,30 +54,29 @@ type nameServiceApp struct {
 	nsKeeper            nameservice.Keeper
 }
 
+// NewNameServiceApp is a constructor function for nameServiceApp
 func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 
-  // First define the top level codec that will be shared by the different modules
-  cdc := MakeCodec()
+	// First define the top level codec that will be shared by the different modules
+	cdc := MakeCodec()
 
-  // BaseApp handles interactions with Tendermint through the ABCI protocol
-  bApp := bam.NewBaseApp(appName, logger, db, auth.DefaultTxDecoder(cdc))
+	// BaseApp handles interactions with Tendermint through the ABCI protocol
+	bApp := bam.NewBaseApp(appName, logger, db, auth.DefaultTxDecoder(cdc))
 
-  // Here you initialize your application with the store keys it requires
+	// Here you initialize your application with the store keys it requires
 	var app = &nameServiceApp{
 		BaseApp: bApp,
 		cdc:     cdc,
 
 		keyMain:          sdk.NewKVStoreKey("main"),
 		keyAccount:       sdk.NewKVStoreKey("acc"),
-		keyNSnames:       sdk.NewKVStoreKey("ns_names"),
-		keyNSowners:      sdk.NewKVStoreKey("ns_owners"),
-		keyNSprices:      sdk.NewKVStoreKey("ns_prices"),
+		keyNS:            sdk.NewKVStoreKey("ns"),
 		keyFeeCollection: sdk.NewKVStoreKey("fee_collection"),
 		keyParams:        sdk.NewKVStoreKey("params"),
 		tkeyParams:       sdk.NewTransientStoreKey("transient_params"),
 	}
 
-  return app
+	return app
 }
 ```
 
@@ -111,9 +108,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 
 		keyMain:          sdk.NewKVStoreKey("main"),
 		keyAccount:       sdk.NewKVStoreKey("acc"),
-		keyNSnames:       sdk.NewKVStoreKey("ns_names"),
-		keyNSowners:      sdk.NewKVStoreKey("ns_owners"),
-		keyNSprices:      sdk.NewKVStoreKey("ns_prices"),
+		keyNS:            sdk.NewKVStoreKey("ns"),
 		keyFeeCollection: sdk.NewKVStoreKey("fee_collection"),
 		keyParams:        sdk.NewKVStoreKey("params"),
 		tkeyParams:       sdk.NewTransientStoreKey("transient_params"),
@@ -144,9 +139,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 	// It handles interactions with the namestore
 	app.nsKeeper = nameservice.NewKeeper(
 		app.bankKeeper,
-		app.keyNSnames,
-		app.keyNSowners,
-		app.keyNSprices,
+		app.keyNS,
 		app.cdc,
 	)
 
@@ -169,9 +162,7 @@ func NewNameServiceApp(logger log.Logger, db dbm.DB) *nameServiceApp {
 	app.MountStores(
 		app.keyMain,
 		app.keyAccount,
-		app.keyNSnames,
-		app.keyNSowners,
-		app.keyNSprices,
+		app.keyNS,
 		app.keyFeeCollection,
 		app.keyParams,
 		app.tkeyParams,

tutorial/app-complete.md

@@ -23,19 +23,16 @@ The state represents your application at a given moment. It tells how much token
 
 The state of tokens and accounts is defined by the `auth` and `bank` modules, which means you don't have to concern yourself with it for now. What you need to do is define the part of the state that relates specifically to your `nameservice` module.
 
-In the SDK, everything is stored in one store called the `multistore`. Any number of key/value stores (called [`KVStores`](https://godoc.org/github.com/cosmos/cosmos-sdk/types#KVStore) in the Cosmos SDK) can be created in this multistore. For your application, you need to store:
-
-- A mapping of `name` to `value`. Create a `nameStore` in the `multistore` to hold this data.
-- A mapping of `name` to `owner`. Create a `ownerStore` in the `multistore` to hold this data.
-- A mapping of `name` to `price`. Create a `priceStore` in the `multistore` to hold this data.
+In the SDK, everything is stored in one store called the `multistore`. Any number of key/value stores (called [`KVStores`](https://godoc.org/github.com/cosmos/cosmos-sdk/types#KVStore) in the Cosmos SDK) can be created in this multistore. For this application, we will use one store to map `name`s to its respective `whois`, a struct that holds a name's value, owner, and price.
 
 ## Messages
 
 Messages are contained in transactions. They trigger state transitions. Each module defines a list of messages and how to handle them. Here are the messages you need to implement the desired functionality for your nameservice application:
 
 - `MsgSetName`: This message allows name owners to set a value for a given name in the `nameStore`.
-- `MsgBuyName`: This message allows accounts to buy a name and become their owner in the `ownerStore`.
+- `MsgBuyName`: This message allows accounts to buy a name and become its owner in the `ownerStore`.
+  - When someone buys a name, they are required to pay the previous owner of the name a price higher than the price the previous owner paid for it.  If a name does not have a previous owner yet, they must burn a `MinPrice` amount.
 
 When a transaction (included in a block) reaches a Tendermint node, it is passed to the application via the [ABCI](https://github.com/tendermint/tendermint/tree/master/abci) and decoded to get the message. The message is then routed to the appropriate module and handled there according to the logic defined in the `Handler`. If the state needs to be updated, the `Handler` calls the `Keeper` to perform the update. You will learn more about these concepts in the next steps of this tutorial.
 
-### Now that you have decided on how your application functions from a high-level perspective, it is time to [start implementing it](./app-init.md)
+### Now that you have decided on how your application functions from a high-level perspective, it is time to [start implementing it](./app-init.md)

tutorial/app-design.md

@@ -95,4 +95,4 @@ Great! You now have the skeleton of your application; however, it still lacks fu
 
 As you have seen in the [application design](./app-design.md) section, you need three modules for your nameservice: `auth`, `bank` and `nameservice`. The first two already exist, but not the last! The `nameservice` module will define the bulk of your state machine. The next step is to build it.
 
-### In order to complete your application, you need to include modules. Go ahead and [start building your nameservice module](./keeper.md). You will come back to `app.go` later.
+### In order to complete your application, you need to include modules. Go ahead and [start building your nameservice module](./types.md). You will come back to `app.go` later.

tutorial/app-init.md

@@ -19,7 +19,7 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/client/context"
 	"github.com/cosmos/cosmos-sdk/codec"
-	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/sdk-application-tutorial/x/nameservice"
 	"github.com/spf13/cobra"
 )
 
@@ -75,11 +75,7 @@ func GetCmdWhois(queryRoute string, cdc *codec.Codec) *cobra.Command {
 	}
 }
 
-type whoIsRes struct {
-	Value string         `json:"value"`
-	Owner sdk.AccAddress `json:"owner"`
-	Price sdk.Coins      `json:"price"`
-}
+type whoIsRes nameservice.Whois
 
 func (w whoIsRes) String() string {
 	return strings.TrimSpace(fmt.Sprintf(`Owner: %s
@@ -96,6 +92,9 @@ Notes on the above code:
   - The second piece (`nameservice`) is the name of the module to route the query to.
   - Finally there is the specific querier in the module that will be called.
   - In this example the fourth piece is the query. This works because the query parameter is a simple string. To enable more complex query inputs you need to use the second argument of the [`.QueryWithData()`](https://godoc.org/github.com/cosmos/cosmos-sdk/client/context#CLIContext.QueryWithData) function to pass in `data`. For an example of this see the [queriers in the Staking module](https://github.com/cosmos/cosmos-sdk/blob/develop/x/stake/querier/querier.go#L103).
+- Each output type should be something that is both JSON marshallable and stringable (implements the Golang `fmt.Stringer` interface).
+  - So for the output type of `resolve` we wrap the resolution string in a struct called `resolveRes` which is both JSON marshallable and has a `.String()` method.
+  - For the output of Whois, the normal Whois struct is already JSON marshalable, but we need to add a `.String()` method on it.
 
 ## Transactions