feat(ForkStatus): implement ForkStatus API

src/main/java/uk/ac/ic/doc/blocc/dashboard/fabric/BloccConnections.java

@@ -180,7 +180,14 @@ public void connectToChannel(int channelNum) {
   }
 
   public Network getChannel(int channelNum) {
-    return channels.get(channelNum);
+    Network channel = channels.get(channelNum);
+
+    if (channel == null) {
+      throw new IllegalArgumentException(
+          String.format("No connection was established to channel%d", channelNum));
+    }
+
+    return channel;
   }
 
   public void connectToChannels(Iterable<Integer> channelNums) {

src/main/java/uk/ac/ic/doc/blocc/dashboard/forkstatus/ForkStatusController.java

@@ -0,0 +1,34 @@
+package uk.ac.ic.doc.blocc.dashboard.forkstatus;
+
+import org.hyperledger.fabric.client.GatewayException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Profile;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.server.ResponseStatusException;
+
+@RestController
+@Profile({"prod", "fork-status-controller-test"})
+@RequestMapping(path = "/api/v1/forkStatus")
+public class ForkStatusController {
+
+  private final ForkStatusService service;
+
+  @Autowired
+  public ForkStatusController(ForkStatusService service) {
+    this.service = service;
+  }
+
+  @GetMapping
+  public boolean getForkStatus(@RequestParam int containerNum) throws GatewayException {
+    try {
+      return service.getForkStatus(containerNum);
+    } catch (IllegalArgumentException e) {
+      throw new ResponseStatusException(HttpStatus.NOT_FOUND, e.getMessage());
+    }
+  }
+
+}

src/main/java/uk/ac/ic/doc/blocc/dashboard/forkstatus/ForkStatusService.java

@@ -0,0 +1,31 @@
+package uk.ac.ic.doc.blocc.dashboard.forkstatus;
+
+import com.google.gson.Gson;
+import org.hyperledger.fabric.client.Contract;
+import org.hyperledger.fabric.client.GatewayException;
+import org.hyperledger.fabric.client.Network;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Profile;
+import org.springframework.stereotype.Service;
+import uk.ac.ic.doc.blocc.dashboard.fabric.BloccConnections;
+
+@Service
+@Profile("prod")
+public class ForkStatusService {
+
+  private final BloccConnections connections;
+  private final Gson gson = new Gson();
+
+  @Autowired
+  public ForkStatusService(BloccConnections connections) {
+    this.connections = connections;
+  }
+
+  public boolean getForkStatus(int containerNum) throws GatewayException {
+    Network channel = connections.getChannel(containerNum);
+    Contract bscc = channel.getContract("bscc");
+    byte[] checkForkStatuses = bscc.evaluateTransaction("CheckForkStatus",
+        String.format("channel%d", containerNum));
+    return gson.fromJson(new String(checkForkStatuses), Boolean.class);
+  }
+}

src/test/java/uk/ac/ic/doc/blocc/dashboard/forkstatus/ForkStatusControllerTest.java

@@ -0,0 +1,57 @@
+package uk.ac.ic.doc.blocc.dashboard.forkstatus;
+
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(ForkStatusController.class)
+@ActiveProfiles("fork-status-controller-test")
+public class ForkStatusControllerTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private ForkStatusService service;
+
+  @Test
+  public void returnsTrueIfForkDetected() throws Exception {
+    int containerNum = 5;
+    when(service.getForkStatus(containerNum)).thenReturn(true);
+
+    mockMvc.perform(get("/api/v1/forkStatus")
+            .param("containerNum", String.valueOf(containerNum)))
+        .andExpect(status().isOk())
+        .andExpect(content().string("true"));
+  }
+
+  @Test
+  public void returnsFalseIfForkNotDetected() throws Exception {
+    int containerNum = 5;
+    when(service.getForkStatus(containerNum)).thenReturn(false);
+
+    mockMvc.perform(get("/api/v1/forkStatus")
+            .param("containerNum", String.valueOf(containerNum)))
+        .andExpect(status().isOk())
+        .andExpect(content().string("false"));
+  }
+
+  @Test
+  public void returnsNotFoundWhenIllegalArgumentExceptionThrown() throws Exception {
+    int containerNum = 5;
+    when(service.getForkStatus(containerNum)).thenThrow(
+        new IllegalArgumentException("Entity not found"));
+
+    mockMvc.perform(get("/api/v1/forkStatus")
+            .param("containerNum", String.valueOf(containerNum)))
+        .andExpect(status().isNotFound());
+  }
+}

src/test/java/uk/ac/ic/doc/blocc/dashboard/forkstatus/ForkStatusServiceTest.java

@@ -0,0 +1,61 @@
+package uk.ac.ic.doc.blocc.dashboard.forkstatus;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.when;
+
+import org.hyperledger.fabric.client.Contract;
+import org.hyperledger.fabric.client.GatewayException;
+import org.hyperledger.fabric.client.Network;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import uk.ac.ic.doc.blocc.dashboard.fabric.BloccConnections;
+
+public class ForkStatusServiceTest {
+
+  @Mock
+  private BloccConnections connections;
+
+  @Mock
+  private Network channel;
+
+  @Mock
+  private Contract bscc;
+
+  @InjectMocks
+  private ForkStatusService service;
+
+  @BeforeEach
+  public void setUp() {
+    MockitoAnnotations.openMocks(this);
+  }
+
+  @Test
+  public void returnsTrueIfForkDetected() throws GatewayException {
+    int containerNum = 5;
+    when(connections.getChannel(containerNum)).thenReturn(channel);
+    when(channel.getContract("bscc")).thenReturn(bscc);
+    when(bscc.evaluateTransaction("CheckForkStatus", "channel5"))
+        .thenReturn("true".getBytes());
+
+    boolean result = service.getForkStatus(containerNum);
+
+    assertTrue(result);
+  }
+
+  @Test
+  public void returnsFalseIfForkNotDetected() throws GatewayException {
+    int containerNum = 5;
+    when(connections.getChannel(containerNum)).thenReturn(channel);
+    when(channel.getContract("bscc")).thenReturn(bscc);
+    when(bscc.evaluateTransaction("CheckForkStatus", "channel5"))
+        .thenReturn("false".getBytes());
+
+    boolean result = service.getForkStatus(containerNum);
+
+    assertFalse(result);
+  }
+}