feat(rest): endpoint to update a vendor.

Signed-off-by: Rudra Chopra <prabhuchopra@gmail.com>

rest/resource-server/src/docs/asciidoc/vendors.adoc

@@ -70,6 +70,17 @@ include::{snippets}/should_document_create_vendor/http-response.adoc[]
 ===== Links
 include::{snippets}/should_document_create_vendor/links.adoc[]
 
+[[resources-vendor-update]]
+==== Updating a vendor
+
+A `PATCH` request is used to update a vendor.
+
+===== Example request
+include::{snippets}/should_document_update_vendor/curl-request.adoc[]
+
+===== Example response
+include::{snippets}/should_document_update_vendor/http-response.adoc[]
+
 [[resources-vendor-export]]
 ==== Export vendor list
 

rest/resource-server/src/main/java/org/eclipse/sw360/rest/resourceserver/vendor/Sw360VendorService.java

@@ -105,6 +105,28 @@ public void updateVendor(Vendor vendor, User sw360User) {
         }
     }
 
+    public RequestStatus vendorUpdate(Vendor vendor, User sw360User, String id) {
+        try {
+            VendorService.Iface sw360VendorClient = getThriftVendorClient();
+            Vendor existingVendor = sw360VendorClient.getByID(id);
+            if (existingVendor != null) {
+                if (vendor.getShortname() != null) {
+                    existingVendor.setShortname(vendor.getShortname());
+                }
+                if (vendor.getFullname() != null) {
+                    existingVendor.setFullname(vendor.getFullname());
+                }
+                if (vendor.getUrl() != null) {
+                    existingVendor.setUrl(vendor.getUrl());
+                }
+            }
+            RequestStatus requestStatus = sw360VendorClient.updateVendor(existingVendor, sw360User);
+            return requestStatus;
+        } catch (TException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
     public void deleteVendor(Vendor vendor, User sw360User) {
         try {
             VendorService.Iface sw360VendorClient = getThriftVendorClient();

rest/resource-server/src/main/java/org/eclipse/sw360/rest/resourceserver/vendor/VendorController.java

@@ -16,6 +16,8 @@
 import lombok.RequiredArgsConstructor;
 import org.apache.thrift.TException;
 import org.eclipse.sw360.datahandler.common.SW360Utils;
+import org.eclipse.sw360.datahandler.thrift.RequestStatus;
+import org.eclipse.sw360.datahandler.thrift.users.User;
 import org.eclipse.sw360.datahandler.thrift.vendors.Vendor;
 import org.eclipse.sw360.rest.resourceserver.core.HalResource;
 import org.eclipse.sw360.rest.resourceserver.core.RestControllerHelper;
@@ -129,6 +131,30 @@ public ResponseEntity<?> createVendor(
         return ResponseEntity.created(location).body(halResource);
     }
 
+    @Operation(
+            summary = "Update a vendor.",
+            description = "Update a vendor.",
+            tags = {"Vendor"}
+    )
+    @PreAuthorize("hasAuthority('WRITE')")
+    @RequestMapping(value = VENDORS_URL + "/{id}", method = RequestMethod.PATCH)
+    public ResponseEntity<?> updateVendor(
+            @Parameter(description = "The id of the vendor")
+            @PathVariable("id") String id,
+            @Parameter(description = "The vendor to be updated.")
+            @RequestBody Vendor vendor
+    ) {
+        User sw360User = restControllerHelper.getSw360UserFromAuthentication();
+        RequestStatus status = vendorService.vendorUpdate(vendor, sw360User, id);
+        if (RequestStatus.SUCCESS.equals(status)) {
+            return new ResponseEntity<>("Vendor updated successfully", HttpStatus.OK);
+        } else if (RequestStatus.DUPLICATE.equals(status)) {
+            return new ResponseEntity<>("A Vendor with same fullname '" + vendor.getFullname() + "' already exists!", HttpStatus.CONFLICT);
+        } else {
+            return new ResponseEntity<>("sw360 vendor with id '" + id + " cannot be updated.", HttpStatus.CONFLICT);
+        }
+    }
+
     @Override
     public RepositoryLinksResource process(RepositoryLinksResource resource) {
         resource.add(linkTo(VendorController.class).slash("api" + VENDORS_URL).withRel("vendors"));

rest/resource-server/src/test/java/org/eclipse/sw360/rest/resourceserver/restdocs/VendorSpecTest.java

@@ -10,6 +10,7 @@
 package org.eclipse.sw360.rest.resourceserver.restdocs;
 
 import org.apache.thrift.TException;
+import org.eclipse.sw360.datahandler.thrift.RequestStatus;
 import org.eclipse.sw360.datahandler.thrift.vendors.Vendor;
 import org.eclipse.sw360.rest.resourceserver.TestHelper;
 import org.eclipse.sw360.rest.resourceserver.vendor.Sw360VendorService;
@@ -40,6 +41,7 @@
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.patch;
 import static org.springframework.restdocs.request.RequestDocumentation.parameterWithName;
 import static org.springframework.restdocs.request.RequestDocumentation.queryParameters;
 
@@ -56,6 +58,7 @@ public class VendorSpecTest extends TestRestDocsSpecBase {
     private Sw360VendorService vendorServiceMock;
 
     private Vendor vendor;
+    private Vendor vendor3;
 
     @Before
     public void before() throws TException{
@@ -71,11 +74,18 @@ public void before() throws TException{
         vendor2.setShortname("Pivotal");
         vendor2.setUrl("https://pivotal.io/");
 
+        vendor3 = new Vendor();
+        vendor3.setId("987567468");
+        vendor3.setFullname("AMazon Ltd");
+        vendor3.setShortname("AMazon");
+        vendor3.setUrl("https://AMazon.io/");
+
         List<Vendor> vendorList = new ArrayList<>();
         vendorList.add(vendor);
         vendorList.add(vendor2);
 
         given(this.vendorServiceMock.getVendors()).willReturn(vendorList);
+        given(this.vendorServiceMock.vendorUpdate(any(), any(), any())).willReturn(RequestStatus.SUCCESS);
         given(this.vendorServiceMock.getVendorById(eq(vendor.getId()))).willReturn(vendor);
         given(this.vendorServiceMock.exportExcel()).willReturn(ByteBuffer.allocate(10000));
 
@@ -162,6 +172,20 @@ public void should_document_create_vendor() throws Exception {
                         )));
     }
 
+    @Test
+    public void should_document_update_vendor() throws Exception {
+        Map<String, Object> updateVendor = new HashMap<>();
+        updateVendor.put("fullName", "Amazon Ltd");
+        updateVendor.put("shortName", "Amazon");
+        updateVendor.put("url", "https://Amazon.io/");
+        mockMvc.perform(patch("/api/vendors/" + vendor3.getId())
+                        .contentType(MediaTypes.HAL_JSON)
+                        .content(this.objectMapper.writeValueAsString(updateVendor))
+                        .header("Authorization", TestHelper.generateAuthHeader(testUserId, testUserPassword))
+                        .accept(MediaTypes.HAL_JSON))
+                .andExpect(status().isOk());
+    }
+
     @Test
     public void should_document_get_export_vendor() throws Exception{
         mockMvc.perform(get("/api/vendors/exportVendorDetails")