forked from subsquid-quests/single-chain-squid
-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
1 parent
36bbcf5
commit 14f2e58
Showing
1 changed file
with
10 additions
and
73 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -1,96 +1,33 @@ | ||
| [](https://gitpod.io/#https://github.com/subsquid/squid-evm-template) | ||
| # Squid tracking USDC transfers on Ethereum | ||
|
|
||
| # Minimal EVM squid | ||
| This [squid](https://docs.subsquid.io/) captures USDC Transfer events on ETH, stores them in a database and serves the data over a GraphQL API. | ||
|
|
||
| This is a starter template of a squid indexer for EVM networks (Ethereum, Polygon, BSC, etc.). See [Squid SDK docs](https://docs.subsquid.io/) for a complete reference. | ||
| The Ethereum data ingester ("processor") is located in `src/main.ts`. It can be started with `sqd process`. GraphQL server runs as a separate process started by `sqd serve`. You can also use `sqd run` to run all the services at once. | ||
|
|
||
| To extract EVM logs and transactions by a topic or a contract address, use `EvmBatchProcessor.addLog()` and `EvmBatchProcessor.addTransaction()` methods of the `EvmBatchProcessor` instance defined in `src/processor.ts`. | ||
| The squid uses [Subsquid Network](https://docs.subsquid.io/subsquid-network) as its primary data source. | ||
|
|
||
| The requested data is transformed in batches by a single handler provided to the `processor.run()` method. | ||
|
|
||
| For a full list of supported networks and config options, | ||
| check the [`EvmBatchProcessor` overview](https://docs.subsquid.io/develop-a-squid/evm-processor/) and the [configuration page](https://docs.subsquid.io/develop-a-squid/evm-processor/configuration/). | ||
|
|
||
| For a step-by-step migration guide from TheGraph, see [the dedicated docs page](https://docs.subsquid.io/migrate/migrate-subgraph/). | ||
|
|
||
| Dependencies: Node.js, Docker. | ||
| Dependencies: Node.js, Docker, Git. | ||
|
|
||
| ## Quickstart | ||
|
|
||
| ```bash | ||
| # 0. Install @subsquid/cli a.k.a. the sqd command globally | ||
| npm i -g @subsquid/cli | ||
|
|
||
| # 1. Retrieve the template | ||
| sqd init my_squid_name -t evm | ||
| cd my_squid_name | ||
| # 1. Clone the repo | ||
| git clone https://github.com/subsquid-labs/quest-single-chain-squid | ||
| cd quest-single-chain-squid | ||
|
|
||
| # 2. Install dependencies | ||
| npm ci | ||
|
|
||
| # 3. Start a Postgres database container and detach | ||
| # 3. Start containers for the Postgres database and the network query gateway | ||
| sqd up | ||
|
|
||
| # 4. Build and start the processor | ||
| sqd process | ||
|
|
||
| # 5. The command above will block the terminal | ||
| # being busy with fetching the chain data, | ||
| # transforming and storing it in the target database. | ||
| # | ||
| # To start the graphql server open the separate terminal | ||
| # and run | ||
| # 5. Start the GraphQL server by running in yet another terminal | ||
| sqd serve | ||
| ``` | ||
| A GraphiQL playground will be available at [localhost:4350/graphql](http://localhost:4350/graphql). | ||
|
|
||
| ## Dev flow | ||
|
|
||
| ### 1. Define database schema | ||
|
|
||
| Start development by defining the schema of the target database via `schema.graphql`. | ||
| Schema definition consists of regular graphql type declarations annotated with custom directives. | ||
| Full description of `schema.graphql` dialect is available [here](https://docs.subsquid.io/basics/schema-file). | ||
|
|
||
| ### 2. Generate TypeORM classes | ||
|
|
||
| Mapping developers use TypeORM [EntityManager](https://typeorm.io/#/working-with-entity-manager) | ||
| to interact with target database during data processing. All necessary entity classes are | ||
| generated by the squid framework from `schema.graphql`. This is done by running `sqd codegen` | ||
| command. | ||
|
|
||
| ### 3. Generate database migrations | ||
|
|
||
| All database changes are applied through migration files located at `db/migrations`. | ||
| `squid-typeorm-migration(1)` tool provides several commands to drive the process. | ||
|
|
||
| ```bash | ||
| ## drop create the database | ||
| sqd down | ||
| sqd up | ||
|
|
||
| ## replace any old schemas with a new one made from the entities | ||
| sqd migration:generate | ||
| ``` | ||
| See [docs on database migrations](https://docs.subsquid.io/basics/db-migrations) for more details. | ||
|
|
||
| ### 4. Import ABI contract and generate interfaces to decode events | ||
|
|
||
| It is necessary to import the respective ABI definition to decode EVM logs. One way to generate a type-safe facade class to decode EVM logs is by placing the relevant JSON ABIs to `./abi`, then using `squid-evm-typegen(1)` via an `sqd` script: | ||
|
|
||
| ```bash | ||
| sqd typegen | ||
| ``` | ||
|
|
||
| See more details on the [`squid-evm-typegen` doc page](https://docs.subsquid.io/evm-indexing/squid-evm-typegen). | ||
|
|
||
| ## Project conventions | ||
|
|
||
| Squid tools assume a certain [project layout](https://docs.subsquid.io/basics/squid-structure): | ||
|
|
||
| * All compiled js files must reside in `lib` and all TypeScript sources in `src`. | ||
| The layout of `lib` must reflect `src`. | ||
| * All TypeORM classes must be exported by `src/model/index.ts` (`lib/model` module). | ||
| * Database schema must be defined in `schema.graphql`. | ||
| * Database migrations must reside in `db/migrations` and must be plain js files. | ||
| * `sqd(1)` and `squid-*(1)` executables consult `.env` file for environment variables. |