<div  ng-controller="uploadController" >
                                    <div class="form-group col-md-12" >
                                         <div class="form-group">
                                          <input type="file" fileinput="file" filepreview="filepreview"/>

                                          </div>
                                    </div>
                                       <div class=" form-group col-md-6">
                                          <img ng-src="{{filepreview}}" class="img-responsive" ng-show="filepreview" />
                                       </div>
                                    </div>

app.controller(
        "uploadController",
        [ '$scope', '$http', 'uploadService',
                function($scope, $http, uploadService) {
                    $scope.$watch('file', function(newfile, oldfile) {
                        if (angular.equals(newfile, oldfile)) {
                            return;
                        }

                        uploadService.upload(newfile).then(function(res) {
                            console.log("result", res);
                        })
                    });

                } ]).service("uploadService", function($http, $q) {

    return ({
        upload : upload
    });

    function upload(file) {
        var upl = $http({
            method : 'POST',
            url : 'http://jsonplaceholder.typicode.com/posts', // /api/upload
            headers : {
                'Content-Type' : 'multipart/form-data'
            },
            data : {
                upload : file
            },
            transformRequest : function(data, headersGetter) {
                var formData = new FormData();
                angular.forEach(data, function(value, key) {
                    formData.append(key, value);
                });

                var headers = headersGetter();
                delete headers['Content-Type'];

                return formData;
            }
        });
        return upl.then(handleSuccess, handleError);

    }

    function handleError(response, data) {
        if (!angular.isObject(response.data) || !response.data.message) {
            return ($q.reject("An unknown error occurred."));
        }

        return ($q.reject(response.data.message));
    }

    function handleSuccess(response) {
        return (response);
    }

}).directive("fileinput", [ function() {
    return {
        scope : {
            fileinput : "=",
            filepreview : "="
        },
        link : function(scope, element, attributes) {
            element.bind("change", function(changeEvent) {
                scope.fileinput = changeEvent.target.files[0];
                var reader = new FileReader();
                reader.onload = function(loadEvent) {
                    scope.$apply(function() {
                        scope.filepreview = loadEvent.target.result;
                    });
                }
                reader.readAsDataURL(scope.fileinput);
            });
        }
    }
} ]);

@Entity
public class Promocao {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    private String produto;
    private double preco;
    private String marca;
    private String categoria;
    private String uniMedida;
    private String observacao;


    @Column(name = "dataInicio")
    @Temporal(TemporalType.DATE)
    private Date dataInicio;


    @Column(name = "dataFim")
    @Temporal(TemporalType.DATE)
    private Date dataFim;

    private String status;

    @JoinColumn
    @ManyToOne(cascade = CascadeType.REFRESH)
    private Usuario usuario;

    private String foto; //aqui entraria o endereço da imagem

    gets .. sets....

@RestController
@RequestMapping
public class PromocaoController {

    @Autowired
    PromocaoService promocaoService;


    //end points


    @RequestMapping(method=RequestMethod.POST, value="/promocoes", consumes=MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<Promocao> cadastrarPromocao(@RequestBody Promocao promocao){
        Promocao promocaoCadastrada = promocaoService.cadastrar(promocao);
        return new ResponseEntity<Promocao>(promocaoCadastrada, HttpStatus.CREATED);
    }


    @RequestMapping(method=RequestMethod.GET, value="/promocoes", produces=MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<Collection<Promocao>> buscarTodasPromocoes(){

        Collection<Promocao> promocaoBuscadas= promocaoService.buscarTodos();
        return new ResponseEntity<>(promocaoBuscadas, HttpStatus.OK);
    }

    @RequestMapping(method=RequestMethod.GET, value="/promocoes/{id}", produces=MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<Promocao> buscarPromocaoPorId(@PathVariable int id){

        Promocao promocao= promocaoService.buscaPorId(id);
        return new ResponseEntity<>(promocao, HttpStatus.OK);
    }


    @RequestMapping(method=RequestMethod.DELETE, value="/promocoes/{id}")
    public ResponseEntity<Promocao> excluirPromocao(@PathVariable int id){
        Promocao promocaoEncontrada = promocaoService.buscaPorId(id);
        if(promocaoEncontrada == null){
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }

        promocaoService.excluir(promocaoEncontrada);
        return new ResponseEntity<>(HttpStatus.OK);
    }

    @RequestMapping(method=RequestMethod.PUT, value="/promocoes", consumes=MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<Promocao> alterarPromocao(@RequestBody Promocao promocao){
        Promocao promocaoAlterada = promocaoService.alterar(promocao);
        return new ResponseEntity<Promocao>(promocaoAlterada, HttpStatus.OK);
    }

}