Add ability to use multiple dialects (#3)

* feat: add dialect functionality and basic spring implementation for it

* feat: add request parameters

* fix: correct imports, allow spring controllers to use annotations

* fix: move generation of converters to generated services

* fix: allow services to be loaded properly

* fix: correct code smells

* feat: add javadocs

* feat: add docs for dialects

* feat: add docs for dialects

* fix: correct javadoc

Dialects.md

@@ -0,0 +1,11 @@
+# Custom dialects
+
+Defining a new dialect is possible by depending on rest-ahead-processor. Required steps are as following:
+
+1. Create a class implementing `io.github.zskamljic.restahead.polyglot.Dialect`.
+2. Create a file in `main/resources/META-INF/services` named `io.github.zskamljic.restahead.polyglot.Dialect` (note that
+   this is a file name, not a Java package)
+3. In created file add the line with FQCN of the class created in #1.
+4. In project where you want the dialect to be used add the dependency with at least `provided` scope.
+
+For sample implementation see Spring Dialect.

Readme.md

@@ -21,6 +21,7 @@ approach.
 - [Query](#queries)
 - [Responses](#response-types)
 - [Spring Boot](#spring-boot)
+- [Dialects](#dialects)
 
 ## Introduction
 
@@ -357,6 +358,40 @@ public interface DemoService {
 injection. URL property needs to be provided to have a baseUrl configured, converter property is optional and is
 required only if the service requires one, see [response types](#response-types).
 
+### Dialects
+
+The code generator allows for usage of multiple dialects (Default being RestAhead). For example, Spring dialect can be
+used, by adding the dependency:
+
+```xml
+
+<dependency>
+    <groupId>io.github.zskamljic</groupId>
+    <artifactId>rest-ahead-spring-dialect</artifactId>
+    <version>${rest.ahead.version}</version>
+</dependency>
+```
+
+It can then be used as following:
+
+```java
+interface SpringService {
+    @GetMappin("/get")
+    Response performGet(@RequestHeader String header, @RequestParam String query);
+
+    @RequestMapping(method = RequestMethod.GET, value = "/{param}")
+    HttpBinResponse get2(@PathVariable String param);
+
+    @PostMapping("/multipart")
+    HttpBinResponse postFile(@RequestPart MultiPartFile file);
+
+    @PostMapping("/customBody")
+    HttpBinResponse postFormData(@RequestPart Map<String, String> body);
+}
+```
+
+Info on how to declare a new dialect can be seen in [Dialects](Dialects.md)
+
 ## Adding to project
 
 Add the dependencies as following:

demo/pom.xml

@@ -23,6 +23,12 @@
             <version>0.3.0-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>io.github.zskamljic</groupId>
+            <artifactId>rest-ahead-spring-dialect</artifactId>
+            <version>0.3.0-SNAPSHOT</version>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>io.github.zskamljic</groupId>
             <artifactId>rest-ahead-jackson-converter</artifactId>

pom.xml

@@ -22,15 +22,16 @@
         <module>rest-ahead-jackson-converter</module>
         <module>test-report-aggregator</module>
         <module>rest-ahead-spring</module>
+        <module>rest-ahead-spring-dialect</module>
     </modules>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.source>17</maven.compiler.source>
         <maven.compiler.target>17</maven.compiler.target>
         <junit.version>5.8.2</junit.version>
-        <mockito.version>4.2.0</mockito.version>
-        <compiler.plugin.version>3.8.1</compiler.plugin.version>
+        <mockito.version>4.3.1</mockito.version>
+        <compiler.plugin.version>3.9.0</compiler.plugin.version>
         <surefire.version>2.22.2</surefire.version>
         <jacoco.version>0.8.7</jacoco.version>
 
@@ -42,6 +43,10 @@
         <sonar.language>java</sonar.language>
         <sonar.organization>zskamljic-github</sonar.organization>
         <sonar.host.url>https://sonarcloud.io</sonar.host.url>
+        <truth.version>1.1.3</truth.version>
+        <testing.compile.version>0.19</testing.compile.version>
+
+        <spring.version>5.3.15</spring.version>
     </properties>
 
     <url>https://github.com/zskamljic/rest-ahead</url>

rest-ahead-client/src/main/java/io/github/zskamljic/restahead/conversion/MapFormConverter.java

@@ -0,0 +1,31 @@
+package io.github.zskamljic.restahead.conversion;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+/**
+ * The default converter for Map classes.
+ */
+public final class MapFormConverter {
+    private MapFormConverter() {
+    }
+
+    /**
+     * Encodes the given value in format [key]=[URL encoded value] separated by &
+     * @param value the values to encode
+     * @param <K> type of the key
+     * @param <V> type of the value
+     * @return the {@link InputStream} with encoded data
+     */
+    public static <K, V> InputStream formEncode(Map<K, V> value) {
+        var stringValue = value.entrySet()
+            .stream()
+            .map(entry -> entry.getKey() + "=" + URLEncoder.encode(String.valueOf(entry.getValue()), StandardCharsets.UTF_8))
+            .collect(Collectors.joining("&"));
+        return new ByteArrayInputStream(stringValue.getBytes(StandardCharsets.UTF_8));
+    }
+}

rest-ahead-processor/pom.xml

@@ -27,18 +27,6 @@
         </dependency>
 
         <!-- Testing dependencies -->
-        <dependency>
-            <groupId>com.google.truth</groupId>
-            <artifactId>truth</artifactId>
-            <version>1.1.3</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>com.google.testing.compile</groupId>
-            <artifactId>compile-testing</artifactId>
-            <version>0.19</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>
@@ -87,17 +75,4 @@
             </plugin>
         </plugins>
     </build>
-
-    <profiles>
-        <profile>
-            <id>testing only</id>
-            <activation>
-                <jdk>[9,)</jdk>
-            </activation>
-            <properties>
-                <argLine>--add-opens jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED</argLine>
-            </properties>
-        </profile>
-    </profiles>
-
 </project>

rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/FormBodyEncoding.java

@@ -1,12 +1,12 @@
 package io.github.zskamljic.restahead.encoding;
 
-import io.github.zskamljic.restahead.encoding.generation.GenerationStrategy;
+import io.github.zskamljic.restahead.encoding.generation.FormConversionStrategy;
 
 /**
  * Specifies that the type should use form encoding.
  *
  * @param parameterName the name of parameter to encode
  * @param strategy      the strategy to use when generating the conversion code
  */
-public record FormBodyEncoding(String parameterName, GenerationStrategy strategy) implements BodyEncoding {
+public record FormBodyEncoding(String parameterName, FormConversionStrategy strategy) implements BodyEncoding {
 }

rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/MultiPartParameter.java

@@ -7,13 +7,15 @@
 /**
  * A parameter that specifies a part of multipart request.
  *
- * @param httpName the name to use in http transport
- * @param name     the name of function parameter
- * @param type     which type to use when generating the code, empty if it's already an appropriate type
+ * @param httpName        the name to use in http transport
+ * @param name            the name of function parameter
+ * @param type            which type to use when generating the code, empty if it's already an appropriate type
+ * @param extraParameters extra parameters that should be sent to the constructor
  */
 public record MultiPartParameter(
     String httpName,
     String name,
-    Optional<Class<? extends MultiPart>> type
+    Optional<Class<? extends MultiPart>> type,
+    Optional<String> extraParameters
 ) {
 }

rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/generation/ClassGenerationStrategy.java

@@ -20,9 +20,8 @@
 /**
  * Used to generate class to form encoded string conversion.
  */
-public record ClassGenerationStrategy(TypeMirror type) implements GenerationStrategy {
-    @Override
-    public MethodSpec generateMethod() {
+public record ClassGenerationStrategy(TypeMirror type) implements FormConversionStrategy {
+    public MethodSpec generate() {
         var builder = MethodSpec.methodBuilder(Variables.FORM_ENCODE)
             .addModifiers(Modifier.PUBLIC, Modifier.STATIC)
             .addParameter(TypeName.get(type), "value")
@@ -44,7 +43,7 @@ public MethodSpec generateMethod() {
      * @param mirror   the type for which to find a strategy
      * @return generation strategy if no issues were discovered, empty otherwise
      */
-    public static Optional<GenerationStrategy> getIfSupported(Messager messager, Elements elements, Types types, TypeMirror mirror) {
+    public static Optional<FormConversionStrategy> getIfSupported(Messager messager, Elements elements, Types types, TypeMirror mirror) {
         if (!(mirror instanceof DeclaredType declaredType)) return Optional.empty();
 
         var getters = findGetters(declaredType);

rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/generation/GenerationStrategy.java → rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/generation/FormConversionStrategy.java

@@ -1,7 +1,5 @@
 package io.github.zskamljic.restahead.encoding.generation;
 
-import com.squareup.javapoet.MethodSpec;
-
 import javax.annotation.processing.Messager;
 import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.Elements;
@@ -12,7 +10,7 @@
 /**
  * Outlines the generation strategy for some type.
  */
-public sealed interface GenerationStrategy permits ClassGenerationStrategy, MapGenerationStrategy, RecordGenerationStrategy {
+public sealed interface FormConversionStrategy permits ClassGenerationStrategy, MapConversionStrategy, RecordGenerationStrategy {
     /**
      * The type that this strategy applies to. Return from this value will be used to ensure that only one converter
      * will be generated for each type.
@@ -21,13 +19,6 @@ public sealed interface GenerationStrategy permits ClassGenerationStrategy, MapG
      */
     TypeMirror type();
 
-    /**
-     * Generate the method for this type and strategy.
-     *
-     * @return the generated convert method.
-     */
-    MethodSpec generateMethod();
-
     /**
      * Selects an appropriate generation strategy for given type.
      *
@@ -37,9 +28,9 @@ public sealed interface GenerationStrategy permits ClassGenerationStrategy, MapG
      * @param mirror   the type for which to find a strategy
      * @return the strategy or empty if none was found
      */
-    static Optional<GenerationStrategy> select(Messager messager, Elements elements, Types types, TypeMirror mirror) {
+    static Optional<FormConversionStrategy> select(Messager messager, Elements elements, Types types, TypeMirror mirror) {
         Stream<OptionalStrategyProvider> providers = Stream.of(
-            MapGenerationStrategy::getIfSupported,
+            MapConversionStrategy::getIfSupported,
             RecordGenerationStrategy::getIfSupported,
             ClassGenerationStrategy::getIfSupported
         );
@@ -53,6 +44,6 @@ static Optional<GenerationStrategy> select(Messager messager, Elements elements,
      */
     @FunctionalInterface
     interface OptionalStrategyProvider {
-        Optional<GenerationStrategy> getIfSupported(Messager messager, Elements elements, Types types, TypeMirror mirror);
+        Optional<FormConversionStrategy> getIfSupported(Messager messager, Elements elements, Types types, TypeMirror mirror);
     }
 }

rest-ahead-processor/src/main/java/io/github/zskamljic/restahead/encoding/generation/MapConversionStrategy.java

@@ -0,0 +1,48 @@
+package io.github.zskamljic.restahead.encoding.generation;
+
+import io.github.zskamljic.restahead.modeling.TypeValidator;
+
+import javax.annotation.processing.Messager;
+import javax.lang.model.type.DeclaredType;
+import javax.lang.model.type.TypeMirror;
+import javax.lang.model.util.Elements;
+import javax.lang.model.util.Types;
+import javax.tools.Diagnostic;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * Generates a form converter for maps.
+ */
+public record MapConversionStrategy(TypeMirror type) implements FormConversionStrategy {
+
+    /**
+     * Checks if provided type is a Map or one of the subclasses that has string representable keys and values.
+     *
+     * @param elements the elements to fetch type information from
+     * @param types    the types utility to use for typing info
+     * @param mirror   the type for which to find a strategy
+     * @return a strategy if data is valid, empty otherwise
+     */
+    public static Optional<FormConversionStrategy> getIfSupported(Messager messager, Elements elements, Types types, TypeMirror mirror) {
+        var type = elements.getTypeElement(Map.class.getCanonicalName())
+            .asType();
+        if (!types.isAssignable(types.erasure(mirror), type)) {
+            return Optional.empty();
+        }
+        var mapType = (DeclaredType) mirror;
+        var genericArguments = mapType.getTypeArguments();
+        if (genericArguments.size() != 2) return Optional.empty();
+
+        var stringValidator = new TypeValidator(elements, types);
+        var key = genericArguments.get(0);
+        var value = genericArguments.get(1);
+
+        if (stringValidator.isUnsupportedType(key) || stringValidator.isUnsupportedType(value)) {
+            messager.printMessage(Diagnostic.Kind.ERROR, "Maps must consist of string representable values to be formEncoded", mapType.asElement());
+            return Optional.empty();
+        }
+
+        return Optional.of(new MapConversionStrategy(types.erasure(type)));
+    }
+}