refactor: simpler decode functions

Author: jasonkuhrt

src/extensions/CustomScalars/decode.ts

@@ -28,29 +28,29 @@ export const decodeResultData = ({ request, data, sddm, scalars }: {
   if (!sddmOutputObject) return
   if (!data) return
 
-  for (const [key, value] of Object.entries(data)) {
-    const documentField = findDocumentField(request.operation.selectionSet, key)
-    const kSchema = documentField?.name.value ?? key
-    const sddmOutputField = sddmOutputObject.f[kSchema]
-    if (!sddmOutputField?.nt) continue
-
-    decodeResultValue({
-      parentContext: { type: `object`, object: data, key },
-      value,
-      sddmNode: sddmOutputField.nt,
-      documentPart: documentField?.selectionSet ?? null,
-      scalars,
-    })
-  }
+  decodeResultValue({
+    parentContext: null,
+    value: data,
+    sddmNode: sddmOutputObject,
+    documentPart: request.operation.selectionSet,
+    scalars,
+  })
 }
 
 const decodeResultValue = (input: {
-  parentContext: { type: `object`; object: Record<string, any>; key: string } | {
-    type: `list`
-    object: any[]
-    key: number
-  }
-  value: Value
+  parentContext:
+    | null
+    | {
+      type: `object`
+      object: Record<string, any>
+      fieldName: string
+    }
+    | {
+      type: `list`
+      object: any[]
+      index: number
+    }
+  value: Grafaid.SomeFieldData
   sddmNode: SchemaDrivenDataMap.OutputNodes
   documentPart: null | Grafaid.Document.SelectionSetNode
   scalars: Schema.Scalar.ScalarMap
@@ -65,7 +65,7 @@ const decodeResultValue = (input: {
     // todo test case of array data of scalars
     value.forEach((item, index) => {
       decodeResultValue({
-        parentContext: { type: `list`, object: value, key: index },
+        parentContext: { type: `list`, object: value, index },
         value: item,
         sddmNode,
         documentPart,
@@ -79,34 +79,41 @@ const decodeResultValue = (input: {
       // todo in strict mode throw error that sddmNode is inconsistent with data shape.
     }
     const object = value
-    for (const [key, value] of Object.entries(object)) {
-      const documentField = findDocumentField(documentPart, key)
-      const kSchema = documentField?.name.value ?? key
+    for (const [fieldName, value] of Object.entries(object)) {
+      // TODO optimize field lookup
+      // We need a smart algorithm that considers:
+      // key space of schema vs key space of data
+      const documentField = findDocumentField(documentPart, fieldName)
+      const kSchema = documentField?.name.value ?? fieldName
       const sddmOutputField = sddmNode.f[kSchema]
       if (!sddmOutputField?.nt) continue
       decodeResultValue({
-        parentContext: { type: `object`, object, key },
+        parentContext: { type: `object`, object, fieldName },
         value,
         sddmNode: sddmOutputField.nt,
         documentPart: documentField?.selectionSet ?? null,
         scalars,
       })
     }
   } else {
+    if (!parentContext) {
+      // Should be impossible. Strict mode could error here.
+      return
+    }
     if (SchemaDrivenDataMap.isScalar(sddmNode)) {
       const decodedValue = Schema.Scalar.applyCodec(sddmNode.codec.decode, value)
       if (parentContext.type === `object`) {
-        parentContext.object[parentContext.key] = decodedValue
+        parentContext.object[parentContext.fieldName] = decodedValue
       } else {
-        parentContext.object[parentContext.key] = decodedValue
+        parentContext.object[parentContext.index] = decodedValue
       }
     } else if (SchemaDrivenDataMap.isCustomScalarName(sddmNode)) {
       const scalar = Schema.Scalar.lookupCustomScalarOrFallbackToString(scalars, sddmNode)
       const decodedValue = Schema.Scalar.applyCodec(scalar.codec.decode, value)
       if (parentContext.type === `object`) {
-        parentContext.object[parentContext.key] = decodedValue
+        parentContext.object[parentContext.fieldName] = decodedValue
       } else {
-        parentContext.object[parentContext.key] = decodedValue
+        parentContext.object[parentContext.index] = decodedValue
       }
     } else {
       // enums not decoded.
@@ -116,23 +123,19 @@ const decodeResultValue = (input: {
 
 const findDocumentField = (
   selectionSet: null | Grafaid.Document.SelectionSetNode,
-  k: string,
+  fieldName: string,
 ): Grafaid.Document.FieldNode | null => {
   if (!selectionSet) return null
 
   for (const selection of selectionSet.selections) {
-    if (selection.kind === Kind.FIELD && (selection.alias?.value ?? selection.name.value) === k) {
+    if (selection.kind === Kind.FIELD && (selection.alias?.value ?? selection.name.value) === fieldName) {
       return selection
     }
     if (selection.kind === Kind.INLINE_FRAGMENT) {
-      const result = findDocumentField(selection.selectionSet, k)
+      const result = findDocumentField(selection.selectionSet, fieldName)
       if (result !== null) return result
     }
   }
 
   return null
 }
-
-type Value = Grafaid.Schema.StandardScalarRuntimeTypes[] | Grafaid.Schema.StandardScalarRuntimeTypes | null | {
-  [k: string]: Value
-}

src/lib/grafaid/request.ts

@@ -31,8 +31,17 @@ export type Variables = {
   [key: string]: string | boolean | null | number | Variables
 }
 
-export type SomeObjectData = Record<string, any>
-export type SomeFieldData = SomeObjectData | Grafaid.Schema.StandardScalarRuntimeTypes
+export type SomeObjectData = {
+  [fieldName: string]: any // SomeFieldData <-- If we put this here tsc has crashes with OOM.
+}
+
+export type SomeFieldData =
+  | null
+  | Grafaid.Schema.StandardScalarRuntimeTypes
+  | Grafaid.Schema.StandardScalarRuntimeTypes[]
+  | {
+    [fieldName: string]: SomeFieldData
+  }
 
 export type GraphQLExecutionResultError = Errors.ContextualAggregateError<GraphQLError>
 

website/content/guides/20_getting-started.md

@@ -4,7 +4,7 @@ title: Getting Started
 
 # Getting Started
 
-This short guide will shepherd you through an example beginning from basic usage an then demonstrating use of the optional document builder. Node is used but Deno and Bun users should be able to follow along as well.
+This short guide will take you from basic usage to use of the optional document builder. Node is used but Deno and Bun users should be able to follow along as well.
 
 ## 🏡 Setup Your Project
 
@@ -24,7 +24,7 @@ pnpm add --development typescript tsx @tsconfig/strictest
 ```
 
 ```sh
-touch tsconfig.json
+touch tsconfig.json main.ts
 ```
 
 ```json tsconfig.json