Support Multi-Value QueryParam/Headers/Cookies

http-api/src/main/java/io/avaje/http/api/PathTypeConversion.java

@@ -2,7 +2,11 @@
 
 import java.math.BigDecimal;
 import java.time.*;
+import java.util.List;
+import java.util.Set;
 import java.util.UUID;
+import java.util.function.Function;
+import java.util.stream.Collectors;
 
 /**
  * Helper type conversion methods.
@@ -11,6 +15,8 @@
  */
 public final class PathTypeConversion {
 
+  private PathTypeConversion() {}
+
   /**
    * Return the value if non-null and otherwise the default value.
    *
@@ -22,6 +28,10 @@ public static String withDefault(String value, String defaultValue) {
     return value != null ? value : defaultValue;
   }
 
+  public static List<String> withDefault(List<String> value, String defaultValue) {
+    return value != null && !value.isEmpty() ? value : List.of(defaultValue);
+  }
+
   /**
    * Check for null for a required property throwing RequiredArgumentException
    * if the value is null.
@@ -41,9 +51,15 @@ private static void checkNull(String value) {
     }
   }
 
-  /**
-   * Convert to int.
-   */
+  public static <T> List<T> list(Function<String, T> func, List<String> params) {
+    return params.stream().map(func).collect(Collectors.toList());
+  }
+
+  public static <T> Set<T> set(Function<String, T> func, List<String> params) {
+    return params.stream().map(func).collect(Collectors.toSet());
+  }
+
+  /** Convert to int. */
   public static int asInt(String value) {
     checkNull(value);
     try {

http-api/src/test/java/io/avaje/http/api/PathTypeConversionTest.java

@@ -7,6 +7,7 @@
 import java.time.LocalDateTime;
 import java.time.LocalTime;
 import java.time.OffsetDateTime;
+import java.util.List;
 import java.util.UUID;
 
 import static org.assertj.core.api.AssertionsForInterfaceTypes.assertThat;
@@ -19,7 +20,9 @@ class PathTypeConversionTest {
   void withDefault() {
     assertEquals("a", PathTypeConversion.withDefault("a", "myVal"));
     assertEquals("", PathTypeConversion.withDefault("", "myVal"));
-    assertEquals("myVal", PathTypeConversion.withDefault(null, "myVal"));
+    String nully = null;
+    assertEquals("myVal", PathTypeConversion.withDefault(nully, "myVal"));
+    assertThat(PathTypeConversion.withDefault(List.of(), "myVal")).anyMatch(s -> "myVal".equals(s));
   }
 
   @Test

http-client/src/main/java/io/avaje/http/client/DHttpClientRequest.java

@@ -125,6 +125,14 @@ public HttpClientRequest header(String name, String value) {
 
   @Override
   public HttpClientRequest header(String name, Object value) {
+
+    if (value instanceof Collection) {
+      for (final var e : (Collection) value) {
+        header(name, e);
+      }
+      return this;
+    }
+
     return value != null ? header(name, value.toString()) : this;
   }
 

http-client/src/main/java/io/avaje/http/client/HttpClientRequest.java

@@ -109,9 +109,10 @@ public interface HttpClientRequest {
   HttpClientRequest header(String name, String value);
 
   /**
-   * Add the header to the request implicitly converting the value to a String.
+   * Add the header to the request implicitly converting the value to a String. If the value is a
+   * collection then it's values are appended with the same key
    *
-   * @param name  The header name
+   * @param name The header name
    * @param value The header value
    * @return The request being built
    */
@@ -218,7 +219,7 @@ public interface HttpClientRequest {
   HttpClientRequest queryParam(String name, String value);
 
   /**
-   * Add a query parameter
+   * Add a query parameter, if value is a collection then it's values are appended with the same key
    *
    * @param name  The name of the query parameter
    * @param value The value of the query parameter which can be null

http-client/src/main/java/io/avaje/http/client/UrlBuilder.java

@@ -2,6 +2,7 @@
 
 import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
+import java.util.Collection;
 import java.util.Map;
 
 /**
@@ -84,6 +85,14 @@ public UrlBuilder queryParam(String name, String value) {
    * The name and value parameters are url encoded.
    */
   public UrlBuilder queryParam(String name, Object value) {
+
+    if (value instanceof Collection) {
+      for (var e : (Collection) value) {
+        queryParam(name, e);
+      }
+      return this;
+    }
+
     if (value != null) {
       addQueryParam(name, value.toString());
     }

http-generator-client/src/main/java/io/avaje/http/generator/client/ClientPlatformAdapter.java

@@ -54,4 +54,17 @@ public void writeReadParameter(Append writer, ParamType paramType, String paramN
   public void writeReadParameter(Append writer, ParamType paramType, String paramName, String paramDefault) {
 
   }
+
+  @Override
+  public void writeReadCollectionParameter(
+      Append writer, ParamType paramType, String paramName) { 
+  }
+
+  @Override
+  public void writeReadCollectionParameter(
+      Append writer,
+      ParamType paramType,
+      String paramName,
+      String paramDefault) {
+  }
 }

http-generator-core/src/main/java/io/avaje/http/generator/core/ElementReader.java

@@ -2,6 +2,7 @@
 
 import static io.avaje.http.generator.core.ParamType.RESPONSE_HANDLER;
 
+import java.util.Objects;
 import java.util.Optional;
 
 import javax.lang.model.element.Element;
@@ -24,6 +25,7 @@ public class ElementReader {
   private final boolean formMarker;
   private final boolean contextType;
   private final boolean useValidation;
+  private final boolean specialParam;
 
   private String paramName;
   private ParamType paramType;
@@ -32,6 +34,7 @@ public class ElementReader {
   private String paramDefault;
 
   private boolean notNullKotlin;
+  private boolean isParamCollection;
   //private boolean notNullJavax;
 
   ElementReader(Element element, ProcessingContext ctx, ParamType defaultType, boolean formMarker) {
@@ -46,18 +49,14 @@ public class ElementReader {
     this.shortType = Util.shortName(rawType);
     this.contextType = ctx.platform().isContextType(rawType);
 
-    if (type != null
-        && (defaultType == ParamType.FORMPARAM || defaultType == ParamType.QUERYPARAM)
-        && Optional.ofNullable(ctx.typeElement(type.mainType()))
-            .map(TypeElement::getKind)
-            .filter(ElementKind.ENUM::equals)
-            .isPresent()) {
+    this.specialParam =
+        defaultType == ParamType.FORMPARAM
+            || defaultType == ParamType.QUERYPARAM
+            || defaultType == ParamType.HEADER
+            || defaultType == ParamType.COOKIE;
 
-      this.typeHandler = TypeMap.enumParamHandler(type);
-    } else {
+    typeHandler = initTypeHandler();
 
-      this.typeHandler = TypeMap.get(rawType);
-    }
     this.formMarker = formMarker;
     this.varName = element.getSimpleName().toString();
     this.snakeName = Util.snakeCase(varName);
@@ -71,6 +70,46 @@ public class ElementReader {
     }
   }
 
+  TypeHandler initTypeHandler() {
+
+    if (specialParam) {
+
+      final var typeOp =
+          Optional.ofNullable(type).or(() -> Optional.of(UType.parse(element.asType())));
+
+      final var mainTypeEnum =
+          typeOp
+              .flatMap(t -> Optional.ofNullable(ctx.typeElement(t.mainType())))
+              .map(TypeElement::getKind)
+              .filter(ElementKind.ENUM::equals)
+              .isPresent();
+
+      final var isCollection =
+          typeOp
+              .filter(t -> t.isGeneric() && !t.mainType().startsWith("java.util.Map"))
+              .isPresent();
+
+      if (mainTypeEnum) {
+        return TypeMap.enumParamHandler(type);
+      } else if (isCollection) {
+        this.isParamCollection = true;
+        if (paramType == ParamType.FORMPARAM) {
+          throw new IllegalStateException("You can't have a single Form Parameter be a list");
+        }
+        final var isEnumCollection =
+            typeOp
+                .flatMap(t -> Optional.ofNullable(ctx.typeElement(t.param0())))
+                .map(TypeElement::getKind)
+                .filter(ElementKind.ENUM::equals)
+                .isPresent();
+
+        return TypeMap.collectionHandler(typeOp.orElseThrow(), isEnumCollection);
+      }
+    }
+
+    return TypeMap.get(rawType);
+  }
+
   private boolean useValidation() {
     if (typeHandler != null) {
       return false;
@@ -182,10 +221,8 @@ private String handlerShortType() {
 
   void addImports(ControllerReader bean) {
     if (typeHandler != null) {
-      String importType = typeHandler.importType();
-      if (importType != null) {
-        bean.addImportType(rawType);
-      }
+      typeHandler.importTypes().stream().filter(Objects::nonNull).forEach(bean::addImportType);
+
     } else {
       bean.addImportType(rawType);
     }
@@ -285,19 +322,24 @@ private boolean setValue(Append writer, PathSegments segments, String shortType)
       // this is a body (POST, PATCH)
       writer.append(ctx.platform().bodyAsClass(type));
 
-    } else {
+    } else if (isParamCollection && specialParam) {
       if (hasParamDefault()) {
-        ctx.platform().writeReadParameter(writer, paramType, paramName, paramDefault);
+        ctx.platform().writeReadCollectionParameter(writer, paramType, paramName, paramDefault);
       } else {
-        boolean checkNull = notNullKotlin || (paramType == ParamType.FORMPARAM && typeHandler.isPrimitive());
-        if (checkNull) {
-          writer.append("checkNull(");
-        }
-        ctx.platform().writeReadParameter(writer, paramType, paramName);
-        //writer.append("ctx.%s(\"%s\")", paramType, paramName);
-        if (checkNull) {
-          writer.append(", \"%s\")", paramName);
-        }
+        ctx.platform().writeReadCollectionParameter(writer, paramType, paramName);
+      }
+    } else if (hasParamDefault()) {
+      ctx.platform().writeReadParameter(writer, paramType, paramName, paramDefault);
+    } else {
+      final var checkNull =
+          notNullKotlin || (paramType == ParamType.FORMPARAM && typeHandler.isPrimitive());
+      if (checkNull) {
+        writer.append("checkNull(");
+      }
+      ctx.platform().writeReadParameter(writer, paramType, paramName);
+      // writer.append("ctx.%s(\"%s\")", paramType, paramName);
+      if (checkNull) {
+        writer.append(", \"%s\")", paramName);
       }
     }
 

http-generator-core/src/main/java/io/avaje/http/generator/core/PlatformAdapter.java

@@ -46,4 +46,9 @@ public interface PlatformAdapter {
   void writeReadParameter(Append writer, ParamType paramType, String paramName);
 
   void writeReadParameter(Append writer, ParamType paramType, String paramName, String paramDefault);
+
+  void writeReadCollectionParameter(Append writer, ParamType paramType, String paramName);
+
+  void writeReadCollectionParameter(Append writer, ParamType paramType, String paramName, String paramDefault);
+
 }

http-generator-core/src/main/java/io/avaje/http/generator/core/TypeHandler.java

@@ -1,5 +1,7 @@
 package io.avaje.http.generator.core;
 
+import java.util.List;
+
 /**
  * Handles type conversion for path and query parameters.
  */
@@ -18,7 +20,7 @@ interface TypeHandler {
   /**
    * The type for adding to imports.
    */
-  String importType();
+  List<String> importTypes();
 
   /**
    * The short name.