[Kotlin] Handle File Downloading

Author: Astakhov, Andrew

modules/swagger-codegen/src/main/resources/kotlin-client/api.mustache

@@ -23,7 +23,13 @@ class {{classname}}(basePath: kotlin.String = "{{{basePath}}}") : ApiClient(base
     fun {{operationId}}({{#allParams}}{{paramName}}: {{{dataType}}}{{#hasMore}}, {{/hasMore}}{{/allParams}}) : {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Unit{{/returnType}} {
         val localVariableBody: kotlin.Any? = {{#hasBodyParam}}{{#bodyParams}}{{paramName}}{{/bodyParams}}{{/hasBodyParam}}{{^hasBodyParam}}{{^hasFormParams}}null{{/hasFormParams}}{{#hasFormParams}}mapOf({{#formParams}}"{{{baseName}}}" to "${{paramName}}"{{#hasMore}}, {{/hasMore}}{{/formParams}}){{/hasFormParams}}{{/hasBodyParam}}
         val localVariableQuery: MultiValueMap = {{^hasQueryParams}}mapOf(){{/hasQueryParams}}{{#hasQueryParams}}mapOf({{#queryParams}}"{{baseName}}" to {{#isContainer}}toMultiValue({{paramName}}.toList(), "{{collectionFormat}}"){{/isContainer}}{{^isContainer}}listOf("${{paramName}}"){{/isContainer}}{{#hasMore}}, {{/hasMore}}{{/queryParams}}){{/hasQueryParams}}
-        val localVariableHeaders: kotlin.collections.Map<kotlin.String,kotlin.String> = mapOf({{#hasFormParams}}"Content-Type" to "multipart/form-data"{{/hasFormParams}}{{^hasHeaderParams}}){{/hasHeaderParams}}{{#hasHeaderParams}}{{#hasFormParams}}, {{/hasFormParams}}{{#headerParams}}"{{baseName}}" to {{#isContainer}}{{paramName}}.joinToString(separator = collectionDelimiter("{{collectionFormat}}"){{/isContainer}}{{^isContainer}}{{paramName}}{{/isContainer}}{{#hasMore}}, {{/hasMore}}{{/headerParams}}){{/hasHeaderParams}}
+        
+        val contentHeaders: kotlin.collections.Map<kotlin.String,kotlin.String> = mapOf({{#hasFormParams}}"Content-Type" to "multipart/form-data"{{/hasFormParams}})
+        val acceptsHeaders: kotlin.collections.Map<kotlin.String,kotlin.String> = mapOf({{#hasProduces}}"Accept" to "{{#produces}}{{#isContainer}}{{mediaType}}.joinToString(separator = collectionDelimiter("{{collectionFormat}}"){{/isContainer}}{{^isContainer}}{{mediaType}}{{/isContainer}}{{#hasMore}}, {{/hasMore}}{{/produces}}"{{/hasProduces}})
+        val localVariableHeaders: kotlin.collections.MutableMap<kotlin.String,kotlin.String> = mutableMapOf({{#hasHeaderParams}}{{#headerParams}}"{{baseName}}" to {{#isContainer}}{{paramName}}.joinToString(separator = collectionDelimiter("{{collectionFormat}}"){{/isContainer}}{{^isContainer}}{{paramName}}{{/isContainer}}{{#hasMore}}, {{/hasMore}}{{/headerParams}}{{/hasHeaderParams}})
+        localVariableHeaders.putAll(contentHeaders)
+        localVariableHeaders.putAll(acceptsHeaders)
+        
         val localVariableConfig = RequestConfig(
             RequestMethod.{{httpMethod}},
             "{{path}}"{{#pathParams}}.replace("{"+"{{baseName}}"+"}", "${{paramName}}"){{/pathParams}},

modules/swagger-codegen/src/main/resources/kotlin-client/infrastructure/ApiClient.kt.mustache

@@ -2,6 +2,8 @@ package {{packageName}}.infrastructure
 
 import okhttp3.*
 import java.io.File
+import java.io.IOException
+import java.util.regex.Pattern
 
 open class ApiClient(val baseUrl: String) {
     companion object {
@@ -51,12 +53,31 @@ open class ApiClient(val baseUrl: String) {
         TODO("requestBody currently only supports JSON body and File body.")
     }
 
-    inline protected fun <reified T: Any?> responseBody(body: ResponseBody?, mediaType: String = JsonMediaType): T? {
-        if(body == null) return null
-        return when(mediaType) {
-            JsonMediaType -> Serializer.moshi.adapter(T::class.java).fromJson(body.source())
-            else -> TODO()
+    inline protected fun <reified T: Any?> responseBody(response: Response, mediaType: String = JsonMediaType): T? {
+        if(response.body() == null) return null
+        
+        if(T::class.java == java.io.File::class.java){
+            return downloadFileFromResponse(response) as T
         }
+        
+        var contentType = response.headers().get("Content-Type")
+        
+        if(contentType == null) {
+            contentType = JsonMediaType
+        }
+
+		if(isJsonMime(contentType)){
+            return Serializer.moshi.adapter(T::class.java).fromJson(response.body()?.source())
+        } else if(contentType.equals(String.javaClass)){
+            return response.body().toString() as T
+        } else {
+            TODO("Fill in more types!")
+        }
+    }
+    
+    fun isJsonMime(mime: String?): Boolean {
+        val jsonMime = "(?i)^(application/json|[^;/ \t]+/[^;/ \t]+[+]json)[ \t]*(;.*)?$"
+        return mime != null && (mime.matches(jsonMime.toRegex()) || mime == "*/*")
     }
 
     inline protected fun <reified T: Any?> request(requestConfig: RequestConfig, body : Any? = null): ApiInfrastructureResponse<T?> {
@@ -72,7 +93,7 @@ open class ApiClient(val baseUrl: String) {
         }
 
         val url = urlBuilder.build()
-        val headers = requestConfig.headers + defaultHeaders
+        val headers = defaultHeaders + requestConfig.headers
 
         if(headers[ContentType] ?: "" == "") {
             throw kotlin.IllegalStateException("Missing Content-Type header. This is required.")
@@ -113,7 +134,7 @@ open class ApiClient(val baseUrl: String) {
                     response.headers().toMultimap()
             )
             response.isSuccessful -> return Success(
-                    responseBody(response.body(), accept),
+                    responseBody(response, accept),
                     response.code(),
                     response.headers().toMultimap()
             )
@@ -130,4 +151,50 @@ open class ApiClient(val baseUrl: String) {
             )
         }
     }
+    
+    @Throws(IOException::class)
+    fun downloadFileFromResponse(response: Response): File {
+        val file = prepareDownloadFile(response)
+
+        response.body()?.byteStream().use{ input ->
+            File(file.path).outputStream().use { input?.copyTo(it) }
+        }
+
+        return file
+    }
+
+    @Throws(IOException::class)
+    fun prepareDownloadFile(response: Response): File {
+        var filename: String? = null
+        var contentDisposition = response.headers().get("Content-Disposition")
+
+        if(contentDisposition != null && contentDisposition != ""){
+            val pattern = Pattern.compile("filename=['\"]?([^'\"\\s]+)['\"]?")
+            val matcher = pattern.matcher(contentDisposition)
+
+            if (matcher.find())
+                filename = matcher.group(1)
+        }
+        var prefix: String
+        var suffix: String? = null
+
+        if (filename == null) {
+            prefix = "download-"
+            suffix = ""
+        } else {
+            val pos = filename.lastIndexOf('.')
+
+            if (pos == -1) {
+            prefix = filename + "-";
+            } else {
+                prefix = filename.substring(0, pos) + "-"
+                suffix = filename.substring(pos)
+            }
+            // File.createTempFile requires the prefix to be at least three characters long
+        if (prefix.length < 3)
+            prefix = "download-"
+        }
+
+        return File.createTempFile(prefix, suffix);
+    }
 }

samples/client/petstore/kotlin/README.md

@@ -31,7 +31,7 @@ This runs all tests and packages the library.
 <a name="documentation-for-api-endpoints"></a>
 ## Documentation for API Endpoints
 
-All URIs are relative to *http://petstore.swagger.io/v2*
+All URIs are relative to *https://petstore.swagger.io/v2*
 
 Class | Method | HTTP request | Description
 ------------ | ------------- | ------------- | -------------
@@ -83,7 +83,7 @@ Class | Method | HTTP request | Description
 
 - **Type**: OAuth
 - **Flow**: implicit
-- **Authorization URL**: http://petstore.swagger.io/api/oauth/dialog
+- **Authorization URL**: https://petstore.swagger.io/oauth/dialog
 - **Scopes**: 
   - write:pets: modify pets in your account
   - read:pets: read your pets

samples/client/petstore/kotlin/docs/PetApi.md

@@ -1,6 +1,6 @@
 # PetApi
 
-All URIs are relative to *http://petstore.swagger.io/v2*
+All URIs are relative to *https://petstore.swagger.io/v2*
 
 Method | HTTP request | Description
 ------------- | ------------- | -------------
@@ -161,7 +161,7 @@ Name | Type | Description  | Notes
 
 Finds Pets by tags
 
-Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+Muliple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
 
 ### Example
 ```kotlin

samples/client/petstore/kotlin/docs/StoreApi.md

@@ -1,6 +1,6 @@
 # StoreApi
 
-All URIs are relative to *http://petstore.swagger.io/v2*
+All URIs are relative to *https://petstore.swagger.io/v2*
 
 Method | HTTP request | Description
 ------------- | ------------- | -------------
@@ -16,7 +16,7 @@ Method | HTTP request | Description
 
 Delete purchase order by ID
 
-For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
+For valid response try integer IDs with positive integer value. Negative or non-integer values will generate API errors
 
 ### Example
 ```kotlin
@@ -25,7 +25,7 @@ For valid response try integer IDs with value < 1000. Anything above 1000 or
 //import io.swagger.client.models.*
 
 val apiInstance = StoreApi()
-val orderId : kotlin.String = orderId_example // kotlin.String | ID of the order that needs to be deleted
+val orderId : kotlin.Long = 789 // kotlin.Long | ID of the order that needs to be deleted
 try {
     apiInstance.deleteOrder(orderId)
 } catch (e: ClientException) {
@@ -41,7 +41,7 @@ try {
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **orderId** | **kotlin.String**| ID of the order that needs to be deleted |
+ **orderId** | **kotlin.Long**| ID of the order that needs to be deleted |
 
 ### Return type
 
@@ -105,7 +105,7 @@ This endpoint does not need any parameter.
 
 Find purchase order by ID
 
-For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
+For valid response try integer IDs with value >= 1 and <= 10. Other values will generated exceptions
 
 ### Example
 ```kotlin

samples/client/petstore/kotlin/docs/UserApi.md

@@ -1,6 +1,6 @@
 # UserApi
 
-All URIs are relative to *http://petstore.swagger.io/v2*
+All URIs are relative to *https://petstore.swagger.io/v2*
 
 Method | HTTP request | Description
 ------------- | ------------- | -------------
@@ -213,7 +213,7 @@ Get user by user name
 //import io.swagger.client.models.*
 
 val apiInstance = UserApi()
-val username : kotlin.String = username_example // kotlin.String | The name that needs to be fetched. Use user1 for testing.
+val username : kotlin.String = username_example // kotlin.String | The name that needs to be fetched. Use user1 for testing. 
 try {
     val result : User = apiInstance.getUserByName(username)
     println(result)
@@ -230,7 +230,7 @@ try {
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **username** | **kotlin.String**| The name that needs to be fetched. Use user1 for testing. |
+ **username** | **kotlin.String**| The name that needs to be fetched. Use user1 for testing.  |
 
 ### Return type
 
@@ -351,7 +351,7 @@ This can only be done by the logged in user.
 //import io.swagger.client.models.*
 
 val apiInstance = UserApi()
-val username : kotlin.String = username_example // kotlin.String | name that need to be deleted
+val username : kotlin.String = username_example // kotlin.String | name that need to be updated
 val body : User =  // User | Updated user object
 try {
     apiInstance.updateUser(username, body)
@@ -368,7 +368,7 @@ try {
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **username** | **kotlin.String**| name that need to be deleted |
+ **username** | **kotlin.String**| name that need to be updated |
  **body** | [**User**](User.md)| Updated user object |
 
 ### Return type

samples/client/petstore/kotlin/settings.gradle

@@ -1 +1 @@
-rootProject.name = 'kotlin-petstore-client'
+rootProject.name = 'kotlin-client'