How to Index Data on the Fuel Network using Fuel Indexer

Repository: https://github.com/compolabs/fuel-indexer-tutorial

ℹ️ If you have any questions you can ask them in our telegram chat for developers: https://t.me/compolabs_devs.

Welcome to an advanced tutorial by Composability Labs on how to index events on the blockchain fuel.network using the fuel indexer.

You can find the source code for this tutorial here: fuel-indexer-tutorial

⚠️ Before going through this tutorial, make sure you have the required dependencies installed

Counter Contract Test Project

1. Create a test counter project:

forc new counter    
cd counter
cargo generate --init fuellabs/sway templates/sway-test-rs --name counter

2. Add your beta-3 account's private key with some ETH balance (to pay fees) into a .env file at the root of the counter folder.

Example: .env.example

3. Change the Rust SDK version in the Cargo.toml to 0.41.1 to allow usage of beta-3. Your Cargo.toml should look like this: Cargo.toml

4. The code for the contract src/main.sw can be found here: main.sw

5. The test code can be found in tests/harness.rs: harness.rs. This test contains both local node and testnet tests, with the latter used to generate events.

6. Build the contract using forc build.

⚠️ Before building of contract, please ensure that you are using the beta-3 version of the toolchain. You can switch your toolchain to beta-3 using the following commands:

fuelup update
fuelup toolchain install beta-3   
fuelup default beta-3

to come back to latest you can type fuelup default latest

Done! The code is ready. Now let's deploy our contracts. Alternatively, you can use the already deployed contract address on beta-3:

• 0x.. Address: 0xd968d8c91c8f7a4b09e86fb5080a1cb9bcd8b016f2764751e1c900d2be20b0cc
• fuel.. Address: fuel1m95d3jgu3aaykz0gd76sszsuhx7d3vqk7fmyw50peyqd903qkrxq67czu2

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Indexer Instance Test Project

1. Create a new indexer instance near the counter folder:

forc index new counter_indexer --namespace composabilitylabs   
cd counter_indexer

2. First, copy the ABI file from counter/out/debug/counter-abi.json into counter_indexer/.

3. Edit the counter_indexer/schema/counter_indexer.schema.graphql file to match the following schema: counter_indexer.schema.graphql

4. Create a counter_indexer/src/lib.rs file like this: lib.rs

5. Create the counter_indexer/counter_indexer.manifest.yaml manifest as shown here: counter_indexer.manifest.yaml

6. If you want to avoid waiting for a long sync, you can change the start_block at the end from the fuel explorer.

7. Run the database in a Docker container:

docker run -d -p 5432:5432 --name my-postgres -e POSTGRES_PASSWORD=mysecretpassword postgres

8. Run the fuel-indexer:

fuel-indexer run --run-migrations --fuel-node-host beta-3.fuel.network --fuel-node-port 80 --postgres-host 127.0.0.1 --postgres-port 5432 --postgres-password mysecretpassword --postgres-user postgres

9. Deploy the indexer:

forc index deploy

Done! Now you will see some logs like INFO fuel_indexer::ffi: 55: Increment 6 -> 7 in your fuel-indexer shell.

To redeploy the indexer code, you can use the following commands:

forc index remove
forc index deploy

Additionally, the GraphQL playground is available at the URL: http://localhost:29987/api/playground/composabilitylabs/counter_indexer