Expose chain config

build.gradle

@@ -46,6 +46,7 @@ dependencies {
 	implementation "io.springfox:springfox-swagger-ui:3.0.0"
 	implementation 'org.springframework.boot:spring-boot-starter-security'
 	implementation 'org.springframework.boot:spring-boot-starter-data-mongodb'
+	implementation 'org.springframework.boot:spring-boot-starter-validation'
 
 	// iexec
 	implementation "com.iexec.common:iexec-common:$iexecCommonVersion"

gradle.properties

@@ -1,2 +1,2 @@
 version=0.1.1-NEXT-SNAPSHOT
-iexecCommonVersion=5.6.0
+iexecCommonVersion=5.7.0-NEXT-SNAPSHOT

src/main/java/com/iexec/blockchain/config/PublicConfigurationController.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2021 IEXEC BLOCKCHAIN TECH
+ *
+ * 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
+ *
+ *     http://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.iexec.blockchain.config;
+
+import com.iexec.blockchain.tool.ChainConfig;
+import com.iexec.common.config.PublicChainConfig;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.time.Duration;
+
+@RestController
+@RequestMapping("/config")
+public class PublicConfigurationController {
+    private final ChainConfig chainConfig;
+
+    public PublicConfigurationController(ChainConfig chainConfig) {
+        this.chainConfig = chainConfig;
+    }
+
+    /**
+     * Unauthenticated endpoint.
+     */
+    @GetMapping("/chain")
+    public ResponseEntity<PublicChainConfig> getPublicChainConfig() {
+        final Integer blockTime = chainConfig.getBlockTime();
+        final PublicChainConfig publicChainConfig = PublicChainConfig
+                .builder()
+                .blockTime(Duration.ofSeconds(blockTime))
+                .build();
+        return ResponseEntity.ok(publicChainConfig);
+    }
+}

src/main/java/com/iexec/blockchain/security/WebSecurityConfigurationAdapter.java

@@ -26,6 +26,7 @@ protected void configure(HttpSecurity http) throws Exception {
                         "/swagger-ui.html",
                         "/swagger-ui/**",
                         "/webjars/**").anonymous() // <--- END Anonymous swagger access
+                .antMatchers("/config/chain").anonymous()
                 .anyRequest().authenticated()
                 .and()
                 .httpBasic();

src/main/java/com/iexec/blockchain/tool/ChainConfig.java

@@ -16,16 +16,19 @@
 
 package com.iexec.blockchain.tool;
 
-import lombok.AllArgsConstructor;
+import lombok.AccessLevel;
 import lombok.Getter;
-import lombok.NoArgsConstructor;
+
+import javax.annotation.PostConstruct;
+import javax.validation.ConstraintViolationException;
+import javax.validation.Validator;
+import javax.validation.constraints.Positive;
+
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 
 @Component
 @Getter
-@AllArgsConstructor
-@NoArgsConstructor
 public class ChainConfig {
 
     @Value("${chain.id}")
@@ -35,6 +38,7 @@ public class ChainConfig {
     private String nodeAddress;
 
     @Value("${chain.block-time}")
+    @Positive(message = "Block time should be positive")
     private Integer blockTime;
 
     @Value("${chain.hub-address}")
@@ -52,4 +56,17 @@ public class ChainConfig {
     @Value("${chain.broker-url}")
     private String brokerUrl;
 
+    @Getter(AccessLevel.NONE) // no getter
+    private Validator validator;
+
+    public ChainConfig(Validator validator) {
+        this.validator = validator;
+    }
+
+    @PostConstruct
+    private void validate() {
+        if (!validator.validate(this).isEmpty()) {
+            throw new ConstraintViolationException(validator.validate(this));
+        }
+    }
 }