[go-experimental] Add model constructors to initialize non-container vars with defaults

Created by: bkabrda

This PR adds a constructor to all models that initializes non-container vars with proper defaults. It might also be possible to do container vars in the future, but that is pretty tricky (and also not as widely used to my knowledge).

PR checklist

• Read the contribution guidelines.
• If contributing template-only or documentation-only changes which will change sample output, build the project before.
• Run the shell script(s) under ./bin/ (or Windows batch scripts under.\bin\windows) to update Petstore samples related to your fix. This is important, as CI jobs will verify all generator outputs of your HEAD commit, and these must match the expectations made by your contribution. You only need to run ./bin/{LANG}-petstore.sh, ./bin/openapi3/{LANG}-petstore.sh if updating the code or mustache templates for a language ({LANG}) (e.g. php, ruby, python, etc).
• File the PR against the correct branch: master, 4.3.x, 5.0.x. Default: master.
• Copy the technical committee to review the pull request if your PR is targeting a particular programming language.

@antihax (2017/11) @bvwells (2017/12) @grokify (2018/07) @kemokemo (2018/09) @bkabrda (2019/07)

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java

@@ -16,6 +16,7 @@
 
 package org.openapitools.codegen.languages;
 
+import io.swagger.v3.oas.models.media.Schema;
 import io.swagger.v3.oas.models.security.SecurityScheme;
 import org.openapitools.codegen.CodegenModel;
 import org.openapitools.codegen.CodegenProperty;
@@ -23,14 +24,12 @@ import org.openapitools.codegen.CodegenSecurity;
 import org.openapitools.codegen.SupportingFile;
 import org.openapitools.codegen.meta.GeneratorMetadata;
 import org.openapitools.codegen.meta.Stability;
+import org.openapitools.codegen.utils.ModelUtils;
 import org.openapitools.codegen.utils.ProcessUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import static org.openapitools.codegen.utils.StringUtils.camelize;
 
@@ -97,6 +96,59 @@ public class GoClientExperimentalCodegen extends GoClientCodegen {
         return camelize(toModel(name, false));
     }
 
+    public String escapeReservedWord(String name) {
+        if (this.reservedWordsMappings().containsKey(name)) {
+            return this.reservedWordsMappings().get(name);
+        }
+        return name + '_';
+    }
+
+    @Override
+    public String toEnumDefaultValue(String value, String datatype) {
+        String prefix = "";
+        if (enumClassPrefix) {
+            prefix = datatype.toUpperCase(Locale.ROOT) + "_";
+        }
+        return prefix + value;
+    }
+
+    @Override
+    public void updateCodegenPropertyEnum(CodegenProperty var) {
+        // make sure the inline enums have plain defaults (e.g. string, int, float)
+        String enumDefault = null;
+        if (var.isEnum && var.defaultValue != null) {
+            enumDefault = var.defaultValue;
+        }
+        super.updateCodegenPropertyEnum(var);
+        if (var.isEnum && enumDefault != null) {
+            var.defaultValue = enumDefault;
+        }
+    }
+
+    @Override
+    public String toDefaultValue(Schema p) {
+        p = ModelUtils.getReferencedSchema(this.openAPI, p);
+        if (ModelUtils.isStringSchema(p)) {
+            if (p.getDefault() != null) {
+                return "\"" + escapeText((String) p.getDefault()) + "\"";
+            }
+            return null;
+        }
+
+        return super.toDefaultValue(p);
+    }
+
+    @Override
+    public CodegenProperty fromProperty(String name, Schema p) {
+        CodegenProperty prop = super.fromProperty(name, p);
+        String cc = camelize(prop.name, true);
+        if (isReservedWord(cc)) {
+            cc = escapeReservedWord(cc);
+        }
+        prop.nameInCamelCase = cc;
+        return prop;
+    }
+
     @Override
     public Map<String, Object> postProcessModels(Map<String, Object> objs) {
 

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java

@@ -16,6 +16,7 @@
 
 package org.openapitools.codegen.languages;
 
+import io.swagger.v3.oas.models.media.Schema;
 import io.swagger.v3.oas.models.security.SecurityScheme;
 import org.openapitools.codegen.CodegenModel;
 import org.openapitools.codegen.CodegenProperty;
@@ -23,14 +24,12 @@ import org.openapitools.codegen.CodegenSecurity;
 import org.openapitools.codegen.SupportingFile;
 import org.openapitools.codegen.meta.GeneratorMetadata;
 import org.openapitools.codegen.meta.Stability;
+import org.openapitools.codegen.utils.ModelUtils;
 import org.openapitools.codegen.utils.ProcessUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import static org.openapitools.codegen.utils.StringUtils.camelize;
 
@@ -97,6 +96,59 @@ public class GoClientExperimentalCodegen extends GoClientCodegen {
         return camelize(toModel(name, false));
     }
 
+    public String escapeReservedWord(String name) {
+        if (this.reservedWordsMappings().containsKey(name)) {
+            return this.reservedWordsMappings().get(name);
+        }
+        return name + '_';
+    }
+
+    @Override
+    public String toEnumDefaultValue(String value, String datatype) {
+        String prefix = "";
+        if (enumClassPrefix) {
+            prefix = datatype.toUpperCase(Locale.ROOT) + "_";
+        }
+        return prefix + value;
+    }
+
+    @Override
+    public void updateCodegenPropertyEnum(CodegenProperty var) {
+        // make sure the inline enums have plain defaults (e.g. string, int, float)
+        String enumDefault = null;
+        if (var.isEnum && var.defaultValue != null) {
+            enumDefault = var.defaultValue;
+        }
+        super.updateCodegenPropertyEnum(var);
+        if (var.isEnum && enumDefault != null) {
+            var.defaultValue = enumDefault;
+        }
+    }
+
+    @Override
+    public String toDefaultValue(Schema p) {
+        p = ModelUtils.getReferencedSchema(this.openAPI, p);
+        if (ModelUtils.isStringSchema(p)) {
+            if (p.getDefault() != null) {
+                return "\"" + escapeText((String) p.getDefault()) + "\"";
+            }
+            return null;
+        }
+
+        return super.toDefaultValue(p);
+    }
+
+    @Override
+    public CodegenProperty fromProperty(String name, Schema p) {
+        CodegenProperty prop = super.fromProperty(name, p);
+        String cc = camelize(prop.name, true);
+        if (isReservedWord(cc)) {
+            cc = escapeReservedWord(cc);
+        }
+        prop.nameInCamelCase = cc;
+        return prop;
+    }
+
     @Override
     public Map<String, Object> postProcessModels(Map<String, Object> objs) {
 

modules/openapi-generator/src/main/resources/go-experimental/model.mustache

@@ -52,6 +52,44 @@ type {{classname}} struct {
 
 {{^isEnum}}
 {{^vendorExtensions.x-is-one-of-interface}}
+// New{{classname}} instantiates a new {{classname}} object
+// This constructor will assign default values to properties that have it defined,
+// and makes sure properties required by API are set, but the set of arguments
+// will change when the set of required properties is changed
+func New{{classname}}({{#vars}}{{#required}}{{nameInCamelCase}} {{dataType}}, {{/required}}{{/vars}}) *{{classname}} {
+    this := {{classname}}{}
+{{#vars}}
+{{#required}}
+    this.{{name}} = {{nameInCamelCase}}
+{{/required}}
+{{^required}}
+{{#defaultValue}}
+{{^isContainer}}
+    var {{nameInCamelCase}} {{{dataType}}} = {{#isNullable}}{{{dataType}}}{Value: {{/isNullable}}{{{.}}}{{#isNullable}} }{{/isNullable}}
+    this.{{name}} = {{^required}}&{{/required}}{{nameInCamelCase}}
+{{/isContainer}}
+{{/defaultValue}}
+{{/required}}
+{{/vars}}
+    return &this
+}
+
+// New{{classname}}WithDefaults instantiates a new {{classname}} object
+// This constructor will only assign default values to properties that have it defined,
+// but it doesn't guarantee that properties required by API are set
+func New{{classname}}WithDefaults() *{{classname}} {
+    this := {{classname}}{}
+{{#vars}}
+{{#defaultValue}}
+{{^isContainer}}
+    var {{nameInCamelCase}} {{{dataType}}} = {{#isNullable}}{{{dataType}}}{Value: {{/isNullable}}{{{.}}}{{#isNullable}} }{{/isNullable}}
+    this.{{name}} = {{^required}}&{{/required}}{{nameInCamelCase}}
+{{/isContainer}}
+{{/defaultValue}}
+{{/vars}}
+    return &this
+}
+
 {{#vars}}
 {{#required}}
 // Get{{name}} returns the {{name}} field value

modules/openapi-generator/src/main/resources/go-experimental/model_doc.mustache

@@ -16,6 +16,23 @@ Name | Type | Description | Notes
 ## Methods
 
 {{^vendorExtensions.x-is-one-of-interface}}
+### New{{classname}}
+
+`func New{{classname}}({{#vars}}{{#required}}{{nameInCamelCase}} {{dataType}}, {{/required}}{{/vars}}) *{{classname}}`
+
+New{{classname}} instantiates a new {{classname}} object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### New{{classname}}WithDefaults
+
+`func New{{classname}}WithDefaults() *{{classname}}`
+
+New{{classname}}WithDefaults instantiates a new {{classname}} object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 {{#vars}}
 ### Get{{name}}
 

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesAnyType.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesAnyType
+
+`func NewAdditionalPropertiesAnyType() *AdditionalPropertiesAnyType`
+
+NewAdditionalPropertiesAnyType instantiates a new AdditionalPropertiesAnyType object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesAnyTypeWithDefaults
+
+`func NewAdditionalPropertiesAnyTypeWithDefaults() *AdditionalPropertiesAnyType`
+
+NewAdditionalPropertiesAnyTypeWithDefaults instantiates a new AdditionalPropertiesAnyType object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesAnyType) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesArray.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesArray
+
+`func NewAdditionalPropertiesArray() *AdditionalPropertiesArray`
+
+NewAdditionalPropertiesArray instantiates a new AdditionalPropertiesArray object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesArrayWithDefaults
+
+`func NewAdditionalPropertiesArrayWithDefaults() *AdditionalPropertiesArray`
+
+NewAdditionalPropertiesArrayWithDefaults instantiates a new AdditionalPropertiesArray object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesArray) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesBoolean.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesBoolean
+
+`func NewAdditionalPropertiesBoolean() *AdditionalPropertiesBoolean`
+
+NewAdditionalPropertiesBoolean instantiates a new AdditionalPropertiesBoolean object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesBooleanWithDefaults
+
+`func NewAdditionalPropertiesBooleanWithDefaults() *AdditionalPropertiesBoolean`
+
+NewAdditionalPropertiesBooleanWithDefaults instantiates a new AdditionalPropertiesBoolean object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesBoolean) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesClass.md

@@ -18,6 +18,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesClass
+
+`func NewAdditionalPropertiesClass() *AdditionalPropertiesClass`
+
+NewAdditionalPropertiesClass instantiates a new AdditionalPropertiesClass object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesClassWithDefaults
+
+`func NewAdditionalPropertiesClassWithDefaults() *AdditionalPropertiesClass`
+
+NewAdditionalPropertiesClassWithDefaults instantiates a new AdditionalPropertiesClass object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetMapString
 
 `func (o *AdditionalPropertiesClass) GetMapString() map[string]string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesInteger.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesInteger
+
+`func NewAdditionalPropertiesInteger() *AdditionalPropertiesInteger`
+
+NewAdditionalPropertiesInteger instantiates a new AdditionalPropertiesInteger object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesIntegerWithDefaults
+
+`func NewAdditionalPropertiesIntegerWithDefaults() *AdditionalPropertiesInteger`
+
+NewAdditionalPropertiesIntegerWithDefaults instantiates a new AdditionalPropertiesInteger object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesInteger) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesNumber.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesNumber
+
+`func NewAdditionalPropertiesNumber() *AdditionalPropertiesNumber`
+
+NewAdditionalPropertiesNumber instantiates a new AdditionalPropertiesNumber object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesNumberWithDefaults
+
+`func NewAdditionalPropertiesNumberWithDefaults() *AdditionalPropertiesNumber`
+
+NewAdditionalPropertiesNumberWithDefaults instantiates a new AdditionalPropertiesNumber object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesNumber) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesObject.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesObject
+
+`func NewAdditionalPropertiesObject() *AdditionalPropertiesObject`
+
+NewAdditionalPropertiesObject instantiates a new AdditionalPropertiesObject object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesObjectWithDefaults
+
+`func NewAdditionalPropertiesObjectWithDefaults() *AdditionalPropertiesObject`
+
+NewAdditionalPropertiesObjectWithDefaults instantiates a new AdditionalPropertiesObject object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesObject) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/AdditionalPropertiesString.md

@@ -8,6 +8,23 @@ Name | Type | Description | Notes
 
 ## Methods
 
+### NewAdditionalPropertiesString
+
+`func NewAdditionalPropertiesString() *AdditionalPropertiesString`
+
+NewAdditionalPropertiesString instantiates a new AdditionalPropertiesString object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAdditionalPropertiesStringWithDefaults
+
+`func NewAdditionalPropertiesStringWithDefaults() *AdditionalPropertiesString`
+
+NewAdditionalPropertiesStringWithDefaults instantiates a new AdditionalPropertiesString object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetName
 
 `func (o *AdditionalPropertiesString) GetName() string`

samples/client/petstore/go-experimental/go-petstore/docs/Animal.md

@@ -5,10 +5,27 @@
 Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
 **ClassName** | Pointer to **string** |  | 
-**Color** | Pointer to **string** |  | [optional] [default to red]
+**Color** | Pointer to **string** |  | [optional] [default to "red"]
 
 ## Methods
 
+### NewAnimal
+
+`func NewAnimal(className string, ) *Animal`
+
+NewAnimal instantiates a new Animal object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewAnimalWithDefaults
+
+`func NewAnimalWithDefaults() *Animal`
+
+NewAnimalWithDefaults instantiates a new Animal object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
 ### GetClassName
 
 `func (o *Animal) GetClassName() string`