near protocol contract built using templates and building blocks

example.rs

// To conserve gas, efficient serialization is achieved through Borsh (http://borsh.io/)
use near_sdk::borsh::{self, BorshDeserialize, BorshSerialize};
use near_sdk::collections::{LookupMap, UnorderedMap};
use near_sdk::json_types::U128;
use near_sdk::serde_json::json;
use near_sdk::{assert_one_yocto, env, near_bindgen, setup_alloc, AccountId, Balance};
use std::collections::HashMap;
use near_contract_standards::fungible_token::FungibleToken;
use near_contract_standards::fungible_token::metadata::{
    FungibleTokenMetadata, FungibleTokenMetadataProvider, FT_METADATA_SPEC,
};

setup_alloc!();

#[near_bindgen]
#[derive(BorshDeserialize, BorshSerialize)]
pub struct ComposedSmartContract {
  token: FungibleToken,
  // Using String, String for simplicity, in production scenario it will be more mapped to a struct.
  catalog: UnorderedMap<String, String>, 
}

impl Default for ComposedSmartContract {
  fn default() -> Self {
    Self {
        token: FungibleToken::new(),
        ad_campaign_impressions: UnorderedMap::new(StorageKey::AdCampaignImpression),
    }
  }
}

near_contract_standards::impl_fungible_token_core!(Contract, token, on_tokens_burned);
near_contract_standards::impl_fungible_token_storage!(Contract, token, on_account_closed);

// Shared templates build and improved by the community
near_template_standards::impl_non_transferrable_token!(Contract, token, call_back_fn);
near_template_standards::impl_pagination!(Contract, catalog, call_back_fn);

// Domain specific templates 
kirana_network_template_standards::impl_perishable_catalog!(Contract, catalog, call_back_fn);
kirana_network_template_standards::impl_escrowed_sales!(Contract, catalog, call_back_fn);

// Platform specific templates ???
kirana_network_template_standards::impl_event_logs!(Contract, catalog, LIST_OF_METHODS);

#[near_bindgen]
impl ComposedSmartContract {
    // Example code generated by `impl_pagination`
  pub fn list_products(self, take: u8, skip: u32) -> Vec<AdCampaign> {
    // ... generated implementation. Provided by impl_pagination macro
  }
  fn list_products_by_category(self, take: u8, skip: u32) -> Vec<AdCampaign> {
    // ... generated implementation. Provided by impl_pagination macro
  }

  pub fn get_product(self, id: String) -> String {
    // ...generated implementation
  }
  pub fn create_order(self, id: Struct) -> String {
    // ...generated implementation
  }

  /// from impl_event_logs, a set of events will be logged using the Events Format.
  /// https://nomicon.io/Standards/EventsFormat
  
  /// EVENT_JSON:{
  //     "standard": "nepXXX", // TODO: Can we use "knXXX" instead ?
  //     "version": "1.0.0",
  //     "event": "abc_is_triggered"
  // }
  /// kirana network will be watching the network for these events, downstream event driven processing can be handled.
}



#[cfg(test)]
mod tests {
  use super::*;
  use near_sdk::MockedBlockchain;
  use near_sdk::{testing_env, VMContext};

  /** Autogenerated tests omitted for brevity */
}