A GraphQL implementation in Gleam providing query parsing, execution, and introspection support.
Note: If you're looking for a GraphQL client, check out Squall.
- Query parsing and execution
- Mutations with input types
- Subscriptions for real-time updates
- Introspection support
- Type-safe schema builder
- Fragment support (inline and named)
Check out the /example directory for an example with SQLite.
import swell/schema
import swell/executor
import swell/value
// Define your schema
let user_type = schema.object_type("User", "A user", [
schema.field("id", schema.id_type(), "User ID", fn(ctx) {
case ctx.data {
Some(value.Object(fields)) -> {
case list.key_find(fields, "id") {
Ok(id_val) -> Ok(id_val)
Error(_) -> Ok(value.Null)
}
}
_ -> Ok(value.Null)
}
}),
schema.field("name", schema.string_type(), "User name", fn(ctx) {
case ctx.data {
Some(value.Object(fields)) -> {
case list.key_find(fields, "name") {
Ok(name_val) -> Ok(name_val)
Error(_) -> Ok(value.Null)
}
}
_ -> Ok(value.Null)
}
}),
])
let query_type = schema.object_type("Query", "Root query", [
schema.field("user", user_type, "Get a user", fn(_ctx) {
Ok(value.Object([
#("id", value.String("1")),
#("name", value.String("Alice")),
]))
}),
])
let my_schema = schema.schema(query_type, None)
// Execute a query
let result = executor.execute("{ user { id name } }", my_schema, schema.context(None))- Directives not implemented (
@skip,@include, custom directives) - Interface types not implemented
- Custom scalar serialization/deserialization (can define custom scalar types but no validation or coercion beyond built-in types)
gleam test # Run tests
gleam build # Build the package