Delphi REST Client API

A Delphi REST client API to consume REST services written in any programming language.

The API was tested in Delphi 7, XE e XE2, and need Indy 10 to work fine.

Serialization / deserialization is transparent. The objects are transported as JSON format, and the i am using SuperObject as Json framework.

For serialization to work well, the object must be declared as follows, with public fields:

TPerson = class(TObject)
public 
  (* Reflect the java object field names, case-sensitive *)
  id: Integer;
  name: String;
  email: String;

  (* utility function *)
  class function NewFrom(Id: Integer; Name, EMail: String): TPerson;
end;

Samples

• GET

   var
     vLista : TList<TPerson>;
   begin
     vLista := RestClient.Resource('http://localhost:8080/java-rest-server/rest/persons')
                       .Accept(RestUtils.MediaType_Json)
                       .GetAsList<TPerson>();
  

• GET ONE

   var
     vPerson : TPerson;
   begin
     vPerson := RestClient.Resource('http://localhost:8080/java-rest-server/rest/person/1')
                        .Accept(RestUtils.MediaType_Json)
                        .Get<TPerson>();
  

• POST

   var
     vPerson : TPerson;
   begin
     vPerson := TPerson.NewFrom(123, 'Fabricio', 'fabricio.colombo.mva@gmail.com');          
     RestClient.Resource('http://localhost:8080/java-rest-server/rest/person')
               .Accept(RestUtils.MediaType_Json)
               .ContentType(RestUtils.MediaType_Json)
               .Post<TPerson>(vPerson);
  

• PUT

   var
     vPerson : TPerson;
   begin
     vPerson := //Load person
     vPerson.Email := 'new@email.com';
     RestClient.Resource('http://localhost:8080/java-rest-server/rest/person')
               .Accept(RestUtils.MediaType_Json)
               .ContentType(RestUtils.MediaType_Json)
               .Put<TPerson>(vPerson);
  

• DELETE

   var
     vPerson : TPerson;
   begin
     vPerson := //Load person
     RestClient.Resource('http://localhost:8080/java-rest-server/rest/person')
               .Accept(RestUtils.MediaType_Json)
               .ContentType(RestUtils.MediaType_Json)
               .Delete(vPerson);
  

• GET AS DATASET

The fields need be predefined.

    var
      vDataSet: TClientDataSet;
    begin
      vDataSet := TClientDataSet.Create(nil);
      try
        TDataSetUtils.CreateField(vDataSet, ftInteger, 'id');
        TDataSetUtils.CreateField(vDataSet, ftString, 'name', 100);
        TDataSetUtils.CreateField(vDataSet, ftString, 'email', 100);
        vDataSet.CreateDataSet;

       RestClient.Resource(CONTEXT_PATH + 'persons')
                  .Accept(RestUtils.MediaType_Json)
                  .GetAsDataSet(vDataSet);
      finally
        vDataSet.Free;
      end;

• GET AS DYNAMIC DATASET

The fields are created dynamically according to the returned content.

    var
      vDataSet: TDataSet;
    begin
      vDataSet := RestClient.Resource(CONTEXT_PATH + 'persons')
                            .Accept(RestUtils.MediaType_Json)
                            .GetAsDataSet();        
      try
        //Do something
      finally
        vDataSet.Free;
      end;

Java Rest Server

The java project is only for test purpose and has built using Maven and Jersey, so it's needed have installed the JRE 6+ (Java Runtime Environment) and Maven 2 to build and run the application. The Maven bin directory must be included in Windows Path environment variable.

After install Java and Maven just run 'start-java-server.bat' to start the application and 'stop-java-server.bat' to shut down them.

When 'start-java-server.bat' is first run maven dependencies will be downloaded, and it may take a while.