# Basic Usage

This guide assumes you already have a Rust binary setup with Diesel and Juniper. For guidiance on setting up either, see their respective docs.

Install Botanist and it's codegen library in cargo.toml:
```
botanist = "0.1"
botanist_codegen = "0.1"
```
Find your Juniper Context and implement the BotanistContext trait with something like the following:
```
impl BotanistContext for Context {
    type DB = diesel::pg::Pg;
    type Connection = diesel::r2d2::PooledConnection<...>;

    fn get_connection(&self) -> &Self::Connection {
        &self.connection
    }
}
```
Types

It's important to note that both the DB type and the Connection type must be defined in the trait implementation. The DB type should reference your underlying Diesel database type (in this example Postgres/Pg). The connection type should reference the type of connection you'll provide to Botanist in the get_connection function (in this example a type of PooledConnection).
Add the botanist_object attribute and table_name to your Diesel models.

Note

It's important to note that the botanist_attribute must have a context type specified via Context = <Your Context Type>.
```
#[botanist_object(Context = Context)]
#[table_name = "heros"]
pub struct Hero {
    pub id: Uuid,
    pub name: String,
}
```
Finally, add botanist_query and botanist_mutation to your query and mutation structs respectively.
```
pub struct Query;
pub struct Mutation;

#[botanist_query(
    Hero,

    Context = Context,
    PrimaryKey = Uuid,
)]
impl Query {}

#[botanist_mutation(
    Hero,

    Context = Context,
    PrimaryKey = Uuid,
)]
impl Mutation {}
```
All types (Diesel models) that should be queryable must be listed in botanist_query. Types (Diesel models) that should have mutations generated for them must be listed in botanist_mutation. Both botanist_query and botanist_mutation must specify the context type (Context = <Your Context Type>) and primary key type (PrimaryKey = <Your Primary Key Type>). Any resolvers or mutations you explicitly write into the Query or Mutation struct implementations will be preserved.

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