feat: render patternProperties and additionalProperties as fields for Go struct (#301)

Author: jonaslagoni

src/generators/go/GoPreset.ts

@@ -4,9 +4,15 @@ import { Preset, CommonModel, CommonPreset, PresetArgs, EnumPreset } from '../..
 import { StructRenderer, GO_DEFAULT_STRUCT_PRESET } from './renderers/StructRenderer';
 import { EnumRenderer, GO_DEFAULT_ENUM_PRESET } from './renderers/EnumRenderer';
 
+export enum FieldType {
+  field,
+  additionalProperty,
+  patternProperties
+}
 export interface FieldArgs {
   fieldName: string;
   field: CommonModel;
+  type: FieldType;
 }
 
 export interface StructPreset<R extends AbstractRenderer, O extends object = any> extends CommonPreset<R, O> {

src/generators/go/GoRenderer.ts

@@ -2,6 +2,8 @@ import { AbstractRenderer } from '../AbstractRenderer';
 import { GoGenerator, GoOptions } from './GoGenerator';
 import { CommonModel, CommonInputModel, Preset } from '../../models';
 import { FormatHelpers } from '../../helpers/FormatHelpers';
+import { DefaultPropertyNames, getUniquePropertyName } from '../../helpers';
+import { FieldType } from './GoPreset';
 
 /**
  * Common renderer for Go types
@@ -28,6 +30,19 @@ export abstract class GoRenderer extends AbstractRenderer<GoOptions> {
       content.push(renderField);
     }
 
+    if (this.model.additionalProperties !== undefined) {
+      const propertyName = getUniquePropertyName(this.model, DefaultPropertyNames.additionalProperties);
+      const additionalProperty = await this.runFieldPreset(propertyName, this.model.additionalProperties, FieldType.additionalProperty);
+      content.push(additionalProperty);
+    }
+
+    if (this.model.patternProperties !== undefined) {
+      for (const [pattern, patternModel] of Object.entries(this.model.patternProperties)) {
+        const propertyName = getUniquePropertyName(this.model, `${pattern}${DefaultPropertyNames.patternProperties}`);
+        const renderedPatternProperty = await this.runFieldPreset(propertyName, patternModel, FieldType.patternProperties);
+        content.push(renderedPatternProperty);
+      }
+    }
     return this.renderBlock(content);
   }
 
@@ -57,8 +72,8 @@ export abstract class GoRenderer extends AbstractRenderer<GoOptions> {
       : fieldName || '';
   }
 
-  runFieldPreset(fieldName: string, field: CommonModel): Promise<string> {
-    return this.runPreset('field', { fieldName, field });
+  runFieldPreset(fieldName: string, field: CommonModel, type: FieldType = FieldType.field): Promise<string> {
+    return this.runPreset('field', { fieldName, field, type });
   }
 
   renderType(model: CommonModel): string {

src/generators/go/renderers/StructRenderer.ts

@@ -1,5 +1,5 @@
 import { GoRenderer } from '../GoRenderer';
-import { StructPreset } from '../GoPreset';
+import { FieldType, StructPreset } from '../GoPreset';
 
 /**
  * Renderer for Go's `struct` type
@@ -27,8 +27,12 @@ export const GO_DEFAULT_STRUCT_PRESET: StructPreset<StructRenderer> = {
   self({ renderer }) {
     return renderer.defaultSelf();
   },
-  field({ fieldName, field, renderer }) {
+  field({ fieldName, field, renderer, type }) {
     fieldName = renderer.nameField(fieldName, field);
-    return `${ fieldName } ${ renderer.renderType(field)}`;
+    let fieldType = renderer.renderType(field);
+    if (type === FieldType.additionalProperty || type === FieldType.patternProperties) {
+      fieldType = `map[string]${fieldType}`; 
+    }
+    return `${ fieldName } ${ fieldType }`;
   },
 };

test/generators/go/GoGenerator.spec.ts

@@ -20,6 +20,14 @@ describe('GoGenerator', () => {
         array_type: { type: 'array', items: { type: 'string' } },
       },
       required: ['street_name', 'city', 'state', 'house_number', 'array_type'],
+      additionalProperties: {
+        type: 'string'
+      },
+      patternProperties: {
+        '^S(.?*)test&': {
+          type: 'string'
+        }
+      },
     };
     const expected = `// Address represents a Address model.
 type Address struct {
@@ -31,6 +39,8 @@ type Address struct {
   Members []interface{}
   TupleType []interface{}
   ArrayType []string
+  AdditionalProperties map[string]string
+  STestPatternProperties map[string]string
 }`;
 
     const inputModel = await generator.process(doc);
@@ -51,11 +61,15 @@ type Address struct {
       type: 'object',
       properties: {
         property: { type: 'string' },
+      },
+      additionalProperties: {
+        type: 'string'
       }
     };
     const expected = `// CustomStruct represents a CustomStruct model.
 type CustomStruct struct {
   property string
+  additionalProperties string
 }`;
 
     generator = new GoGenerator({ presets: [