rename snake_case fields from server to camelCase fields on client

src/lib/model.ts

@@ -193,17 +193,19 @@ BaseModel.fromJsonApi = function (body) {
 
     // Attributes
     for (let [attribute, value] of Object.entries(body.data.attributes ?? {})) {
+      const attributeName = schema.transformPropertyName(attribute, schema.options?.serverTransform, schema.options?.clientTransform);
       const property = schema.attributes[attribute];
 
       if (property?.type === Date && value) {
         value = new Date(value);
       }
 
-      doc.set(attribute, value, { skipMarkModified: true });
+      doc.set(attributeName, value, { skipMarkModified: true });
     }
 
     // Relationships
     for (const [relationship, value] of Object.entries(body.data.relationships ?? {})) {
+      const relationshipName = schema.transformPropertyName(relationship, schema.options?.serverTransform, schema.options?.clientTransform);
       if (Array.isArray(value.data)) {
         const related = value.data.map((identifier) => {
           const model = models[identifier.type];
@@ -214,7 +216,7 @@ BaseModel.fromJsonApi = function (body) {
           });
         });
 
-        doc.set(relationship, related, { skipMarkModified: true });
+        doc.set(relationshipName, related, { skipMarkModified: true });
       } else if (value.data) {
         const identifier = value.data;
         const model = models[identifier.type];
@@ -224,7 +226,7 @@ BaseModel.fromJsonApi = function (body) {
           data: body.included!.find((resource) => resource.type === identifier.type && resource.id === identifier.id),
         });
 
-        doc.set(relationship, related, { skipMarkModified: true });
+        doc.set(relationshipName, related, { skipMarkModified: true });
       }
     }
 
@@ -473,24 +475,26 @@ BaseModel.prototype.toJsonApi = function () {
       }
     }
 
-    data.attributes![attribute] = value;
+    const attributeName = this.schema.transformPropertyName(attribute, this.schema.options?.clientTransform, this.schema.options?.serverTransform);
+    data.attributes![attributeName] = value;
   }
 
   for (const [relationship, property] of Object.entries(this.schema.relationships)) {
+    const relationshipName = this.schema.transformPropertyName(relationship, this.schema.options?.clientTransform, this.schema.options?.serverTransform);
     if (!this.isNew && !this.isModified(relationship)) continue;
 
     const value = this.get(relationship) as ModelInstance<Record<string, any>> | ModelInstance<Record<string, any>>[] | null;
 
     if (Array.isArray(value)) {
-      data.relationships![relationship] = {
+      data.relationships![relationshipName] = {
         data: value.map((val) => val.identifier()),
       };
     } else if (value) {
-      data.relationships![relationship] = {
+      data.relationships![relationshipName] = {
         data: value.identifier(),
       };
     } else {
-      data.relationships![relationship] = {
+      data.relationships![relationshipName] = {
         data: null,
       };
     }

src/lib/schema.ts

@@ -27,6 +27,7 @@ type AttributeDefinition<T> = {
 }
 
 type RelationshipsDefinition<DocType> = {
+  // I believe I get into trouble here
   [path in keyof DocType]?: RelationshipDefinition<DocType[path]>;
 }
 
@@ -47,7 +48,11 @@ type RelationshipDefinition<T> = {
   transform?: (val: T) => any;
 }
 
+type NameTransformer = "camelCase" | "snake_case" | "literal"
+
 type SchemaOptions<DocType> = {
+  serverTransform?: NameTransformer;
+  clientTransform?: NameTransformer;
 }
 
 class Schema<DocType> {
@@ -63,6 +68,8 @@ class Schema<DocType> {
 
   relationships!: RelationshipsDefinition<DocType>;
 
+  options?: SchemaOptions<DocType>;
+
   init!: (
     definition: SchemaDefinition<DocType>,
     options?: SchemaOptions<DocType>,
@@ -71,11 +78,14 @@ class Schema<DocType> {
   add!: (
     obj: SchemaDefinition<DocType>,
   ) => this;
+
+  transformPropertyName!: (propertyName: string, sourceFormat: NameTransformer | undefined, targetFormat: NameTransformer | undefined) => string;
 }
 
 Schema.prototype.init = function (definition, options) {
   this.attributes = {};
   this.relationships = {};
+  this.options = options || {};
 
   this.add(definition);
 };
@@ -90,5 +100,18 @@ Schema.prototype.add = function (obj) {
   return this;
 };
 
+Schema.prototype.transformPropertyName = function (propertyName: string, sourceFormat: NameTransformer = "literal", targetFormat: NameTransformer = "literal") {
+  if (sourceFormat==="snake_case" && targetFormat === "camelCase") {
+    return propertyName.replace(/_([a-z])/g, (_, letter) => letter.toUpperCase());
+  } else if (sourceFormat === "camelCase" && targetFormat === "snake_case") {
+    return propertyName.replace(/([A-Z])/g, "_$1").toLowerCase();
+  } else if (targetFormat === "literal" || sourceFormat === targetFormat) {
+    return propertyName;
+  } else {
+    console.warn(`Unsupported transformation from ${sourceFormat} to ${targetFormat}`);
+  }
+  return propertyName;
+}
+
 
 export default Schema