Basic implementation

pom.xml

@@ -38,10 +38,34 @@
     </properties>
 
     <dependencies>
+        <dependency>
+            <groupId>com.networknt</groupId>
+            <artifactId>json-schema-validator</artifactId>
+            <version>1.3.3</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-web</artifactId>
+            <version>6.1.4</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>javax.servlet</groupId>
+            <artifactId>servlet-api</artifactId>
+            <version>2.5</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.30</version>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-params</artifactId>
             <version>5.10.2</version>
+            <scope>test</scope>
         </dependency>
     </dependencies>
     <build>

src/main/java/com/unitvectory/jsonschema4springboot/JsonSchemaCache.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import com.networknt.schema.JsonSchema;
+
+/**
+ * JSON Schema Cache interface.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+public interface JsonSchemaCache {
+
+    /**
+     * Get a cached schema.
+     * 
+     * @param path the path
+     * @return the JsonSchema; null if not found
+     */
+    JsonSchema getSchema(String path);
+
+    /**
+     * Cache a JsonSchema
+     * 
+     * @param path the path
+     * @param schema the JsonSchema
+     */
+    void cacheSchema(String path, JsonSchema schema);
+}

src/main/java/com/unitvectory/jsonschema4springboot/JsonSchemaCacheDefault.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import com.networknt.schema.JsonSchema;
+
+/**
+ * The Default JSON Schema Cache implementation.
+ * 
+ * Caches an unbounded number of schemas perpetually.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+class JsonSchemaCacheDefault implements JsonSchemaCache {
+
+    private Map<String, JsonSchema> cache = new ConcurrentHashMap<>();
+
+    @Override
+    public JsonSchema getSchema(String path) {
+        return this.cache.get(path);
+    }
+
+    @Override
+    public void cacheSchema(String path, JsonSchema schema) {
+        this.cache.put(path, schema);
+    }
+}

src/main/java/com/unitvectory/jsonschema4springboot/JsonSchemaLookup.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import com.networknt.schema.JsonSchema;
+import com.networknt.schema.SpecVersion.VersionFlag;
+
+/**
+ * JSON Schema lookup interface.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+public interface JsonSchemaLookup {
+
+    /**
+     * Get a cached schema.
+     * 
+     * @param version the JSON Schema version
+     * @param path the path
+     * @return the JsonSchema; null if not found
+     * @throws ValidateJsonSchemaException schema was unable to be loaded
+     */
+    JsonSchema getSchema(VersionFlag version, String path) throws ValidateJsonSchemaException;
+}

src/main/java/com/unitvectory/jsonschema4springboot/JsonSchemaLookupDefault.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import java.io.InputStream;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import com.networknt.schema.JsonSchema;
+import com.networknt.schema.JsonSchemaFactory;
+import com.networknt.schema.SpecVersion.VersionFlag;
+
+/**
+ * JSON Schema lookup interface.
+ * 
+ * This loads schemas from the class path by default.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+public class JsonSchemaLookupDefault implements JsonSchemaLookup {
+
+    @Override
+    public JsonSchema getSchema(VersionFlag version, String path)
+            throws ValidateJsonSchemaException {
+        // Get the factory for the specified version
+        JsonSchemaFactory schemaFactory = JsonSchemaFactory.getInstance(version);
+
+        // Load the resource from the class path
+        Resource resource = new ClassPathResource(path);
+        if (!resource.exists()) {
+            throw new ValidateJsonSchemaException("JSON Schema not found at path: " + path);
+        }
+
+        // Load the schema
+        try (InputStream schemaStream = resource.getInputStream()) {
+            return schemaFactory.getSchema(schemaStream);
+        } catch (Exception e) {
+            throw new ValidateJsonSchemaException("JSON Schema failed to load from path: " + path,
+                    e);
+        }
+    }
+}

src/main/java/com/unitvectory/jsonschema4springboot/CheckJsonSchema.java → src/main/java/com/unitvectory/jsonschema4springboot/ValidateJsonSchema.java

@@ -13,11 +13,24 @@
  */
 package com.unitvectory.jsonschema4springboot;
 
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
 /**
- * Check the JSON Schema
+ * Validate the JSON Schema
  * 
  * @author Jared Hatfield (UnitVectorY Labs)
  */
-public @interface CheckJsonSchema {
+@Target({ElementType.PARAMETER})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface ValidateJsonSchema {
 
+    /**
+     * The path to the schema
+     * 
+     * @return the path
+     */
+    String schemaPath();
 }

src/main/java/com/unitvectory/jsonschema4springboot/ValidateJsonSchemaArgumentResolver.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Set;
+import javax.servlet.http.HttpServletRequest;
+import org.springframework.core.MethodParameter;
+import org.springframework.util.StreamUtils;
+import org.springframework.web.bind.support.WebDataBinderFactory;
+import org.springframework.web.context.request.NativeWebRequest;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.method.support.ModelAndViewContainer;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.networknt.schema.JsonSchema;
+import com.networknt.schema.ValidationMessage;
+import lombok.AllArgsConstructor;
+
+/**
+ * The argument resolver that supports JSON Schema validation.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+@AllArgsConstructor
+public class ValidateJsonSchemaArgumentResolver implements HandlerMethodArgumentResolver {
+
+    /**
+     * The configuration
+     */
+    private final ValidateJsonSchemaConfig config;
+
+    @Override
+    public final boolean supportsParameter(MethodParameter parameter) {
+        // Only applies to ValidateJsonSchema annotation
+        return parameter.hasParameterAnnotation(ValidateJsonSchema.class);
+    }
+
+    @Override
+    public final Object resolveArgument(MethodParameter parameter,
+            ModelAndViewContainer mavContainer, NativeWebRequest webRequest,
+            WebDataBinderFactory binderFactory) throws Exception {
+        // Get the annotation
+        String schemaPath = parameter.getParameterAnnotation(ValidateJsonSchema.class).schemaPath();
+
+        // First try the cache
+        JsonSchema schema = this.config.getCache().getSchema(schemaPath);
+        if (schema == null) {
+            schema = this.config.getLookup().getSchema(this.config.getSpecVersion(), schemaPath);
+
+            // Failed to get the
+            if (schema == null) {
+                throw new ValidateJsonSchemaException("Failed to load JSON Schema");
+            }
+
+            // Cache the value
+            this.config.getCache().cacheSchema(schemaPath, schema);
+        }
+
+        // Get the JSON as a String
+        HttpServletRequest httpServletRequest =
+                webRequest.getNativeRequest(HttpServletRequest.class);
+        String jsonString = StreamUtils.copyToString(httpServletRequest.getInputStream(),
+                StandardCharsets.UTF_8);
+
+        // Parse into a JsonNode, needed for validation
+        JsonNode json = this.config.getObjectMapper().readTree(jsonString);
+
+        // Validate the Json
+        Set<ValidationMessage> validationResult = schema.validate(json);
+        if (validationResult.isEmpty()) {
+            // Convert the JSON into the object
+            return this.config.getObjectMapper().treeToValue(json, parameter.getParameterType());
+        } else {
+            // Throw the validation exception
+            throw new ValidateJsonSchemaException(validationResult);
+        }
+    }
+}

src/main/java/com/unitvectory/jsonschema4springboot/ValidateJsonSchemaConfig.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.unitvectory.jsonschema4springboot;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.networknt.schema.SpecVersion;
+import lombok.Builder;
+import lombok.Value;
+
+/**
+ * The validate JSON Schema configuration.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+@Value
+@Builder
+public class ValidateJsonSchemaConfig {
+
+    @Builder.Default
+    private final ObjectMapper objectMapper = new ObjectMapper();
+
+    @Builder.Default
+    private final SpecVersion.VersionFlag specVersion = SpecVersion.VersionFlag.V7;
+
+    @Builder.Default
+    private final JsonSchemaCache cache = new JsonSchemaCacheDefault();
+
+    @Builder.Default
+    private final JsonSchemaLookup lookup = new JsonSchemaLookupDefault();
+}