Address comments

backend-rust/README.md

@@ -20,19 +20,20 @@ To run the services, the following dependencies are required to be available on
 For instructions on how to use the indexer run:
 
 ```
-cargo run --bin ccdscan-indexer -- --help
+ccdscan-indexer --help
 ```
 
-Example:
+## Run the Indexer Service during development
+
+Examples:
 
 ```
 cargo run --bin ccdscan-indexer -- --node http://localhost:20001 --max-parallel-block-preprocessors 20 --max-processing-batch 20
-cargo run --bin ccdscan-indexer -- --node http://node.testnet.concordium.com:20000
-cargo run --bin ccdscan-indexer -- --node https://grpc.testnet.concordium.com:20000
+cargo run --bin ccdscan-indexer -- --node https://grpc.testnet.concordium.com:20000 --max-parallel-block-preprocessors 20 --max-processing-batch 20
 ```
 
-Note: Queries like `getSourceModule` might timeout (are disabled) on our public-facing nodes. The recommendation is to run
-your own local node during development.
+Note: Since the indexer puts a lot of load on the node, use your own local node whenever possible.
+If using the public nodes, run the indexer as short as possible.
 
 <!-- TODO When service become stable: add documentation of arguments and environment variables. -->
 
@@ -44,6 +45,8 @@ For instructions on how to use the API service run:
 cargo run --bin ccdscan-api -- --help
 ```
 
+## Run the GraphQL API Service during development
+
 Example:
 
 ```
@@ -173,7 +176,7 @@ This will generate type metadata for the queries in the `.sqlx` folder.
 
 - Feature 2:
 
-If you want to update your database to a new schema, execute the command:
+If you want to drop the entire database and start with an empty database that uses the current schema, execute the command:
 
 ```
 sqlx database reset --force

backend-rust/migrations/0001_initialize.up.sql

@@ -247,15 +247,13 @@ CREATE TABLE bakers(
         BIGINT
 );
 
--- Every WASM module on chain.
+-- Every module on chain.
 CREATE TABLE smart_contract_modules(
-    index
-        BIGINT
-        PRIMARY KEY,
-    -- Module reference of the wasm module.
+    -- Module reference of the module.
     module_reference
         CHAR(64)
         UNIQUE
+        PRIMARY KEY
         NOT NULL,
     -- The absolute block height when the module was deployed.
     deployment_block_height
@@ -265,7 +263,7 @@ CREATE TABLE smart_contract_modules(
     deployment_transaction_index
         BIGINT
         NOT NULL,
-    -- Embedded schema in the wasm module if present.
+    -- Embedded schema in the module if present.
     schema TEXT
 );
 
@@ -280,13 +278,13 @@ CREATE TABLE contracts(
         BIGINT
         NOT NULL,
     -- Note: It might be better to use `module_reference_index` which would save storage space but would require more work in inserting/querying by the indexer.
-    -- Module reference of the wasm module.
+    -- Module reference of the module.
     module_reference
         CHAR(64)
         NOT NULL,
     -- The contract name.
     name
-        TEXT
+        VARCHAR(100)
         NOT NULL,
     -- The total balance of the contract in micro CCD.
     amount

backend-rust/src/graphql_api.rs

@@ -276,7 +276,7 @@ enum ApiError {
     #[error("Invalid integer: {0}")]
     InvalidIntString(#[from] std::num::ParseIntError),
     #[error("Parse error: {0}")]
-    UnsignedLongParse(#[from] UnsignedLongParseError),
+    UnsignedLongNotNegative(#[from] UnsignedLongNotNegativeError),
 }
 
 impl From<sqlx::Error> for ApiError {
@@ -1046,21 +1046,13 @@ impl ScalarType for UnsignedLong {
 }
 
 #[derive(Debug, thiserror::Error, Clone)]
-enum UnsignedLongParseError {
-    #[error("Negative number cannot be converted to UnsignedLong.")]
-    NotNegative,
-}
+#[error("Negative number cannot be converted to UnsignedLong.")]
+struct UnsignedLongNotNegativeError;
 
 impl TryFrom<i64> for UnsignedLong {
-    type Error = UnsignedLongParseError;
+    type Error = <u64 as TryFrom<i64>>::Error;
 
-    fn try_from(number: i64) -> Result<Self, Self::Error> {
-        if number < 0 {
-            Err(UnsignedLongParseError::NotNegative)?
-        } else {
-            Ok(UnsignedLong(number as u64))
-        }
-    }
+    fn try_from(number: i64) -> Result<Self, Self::Error> { Ok(UnsignedLong(number.try_into()?)) }
 }
 
 /// The `Long` scalar type represents non-fractional signed whole 64-bit numeric

backend-rust/src/indexer.rs

@@ -1425,13 +1425,11 @@ impl PreparedModuleDeployed {
         sqlx::query!(
             r#"
 INSERT INTO smart_contract_modules (
-    index,
     module_reference,
     deployment_block_height,
     deployment_transaction_index,
     schema
 ) VALUES (
-  (SELECT COALESCE(MAX(index) + 1, 0) FROM smart_contract_modules),
   $1, $2, $3, $4
 )"#,
             self.module_reference,