（译）Spring Boot + Spring Security

作者: StephenRo | 来源:发表于2019-12-18 11:03 被阅读0次

原文链接: https://www.callicoder.com/spring-boot-spring-security-jwt-mysql-react-app-part-3/

欢迎来到全栈开发系列第三章（Spring Boot，Spring Security，JWT，MySQL，React）。

在本文中，我们将构建以下REST API：创建调查，投票，获取用户资料等。

在Github上查看该项目的完整源代码。

spring-boot-spring-security-jwt-mysql-full-stack-polling-app.jpg

在写API之前，我们需要先创建Poll，Choice和Vote的实体。
我们希望在Poll模型中包括谁发起了这项投票，并将当前登录的用户自动填充到Poll实体中。

创建Auditing模型

为了完成自动填充创建人功能，我们需要定义一个审查模型UserDateAudit继承自DateAudit。
他包含createdBy和updatedBy字段。

UserDateAudit

在com.exmaple.polls.model.audit包下创建UserDateAudit类

package com.example.polls.model.audit;

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import org.springframework.data.annotation.CreatedBy;
import org.springframework.data.annotation.LastModifiedBy;

import javax.persistence.Column;
import javax.persistence.MappedSuperclass;

@MappedSuperclass
@JsonIgnoreProperties(
        value = {"createdBy", "updatedBy"},
        allowGetters = true
)
public abstract class UserDateAudit extends DateAudit {
    @CreatedBy
    @Column(updatable = false)
    private Long createdBy;

    @LastModifiedBy
    private Long updatedBy;

    public Long getCreatedBy() {
        return createdBy;
    }

    public void setCreatedBy(Long createdBy) {
        this.createdBy = createdBy;
    }

    public Long getUpdatedBy() {
        return updatedBy;
    }

    public void setUpdatedBy(Long updatedBy) {
        this.updatedBy = updatedBy;
    }
}

配置Auditing

现在，为了能实现自动填充createdBy和updatedBy字段，我们需要对AuditingConfig做以下修改。

package com.example.polls.config;

import com.example.polls.security.UserPrincipal;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.domain.AuditorAware;
import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
import org.springframework.security.authentication.AnonymousAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import java.util.Optional;

@Configuration
@EnableJpaAuditing
public class AuditingConfig {

    @Bean
    public AuditorAware<Long> auditorProvider() {
        return new SpringSecurityAuditAwareImpl();
    }
}

class SpringSecurityAuditAwareImpl implements AuditorAware<Long> {

    @Override
    public Optional<Long> getCurrentAuditor() {
        Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

        if (authentication == null ||
                !authentication.isAuthenticated() ||
                authentication instanceof AnonymousAuthenticationToken) {
            return Optional.empty();
        }

        UserPrincipal userPrincipal = (UserPrincipal) authentication.getPrincipal();
        
        return Optional.ofNullable(userPrincipal.getId());
    }
}

业务模型

1.Vote类（发起一项民意调查的实体）

Poll实体应由id，question，若干个choices和expirationDateTime字段组成。以下是完整的Poll类。

package com.example.polls.model;

import com.example.polls.model.audit.UserDateAudit;
import org.hibernate.annotations.BatchSize;
import org.hibernate.annotations.Fetch;
import org.hibernate.annotations.FetchMode;
import javax.persistence.*;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;

@Entity
@Table(name = "polls")
public class Poll extends UserDateAudit {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @NotBlank
    @Size(max = 140)
    private String question;

    @OneToMany(
            mappedBy = "poll",
            cascade = CascadeType.ALL,
            fetch = FetchType.EAGER,
            orphanRemoval = true
    )
    @Size(min = 2, max = 6)
    @Fetch(FetchMode.SELECT)
    @BatchSize(size = 30)
    private List<Choice> choices = new ArrayList<>();

    @NotNull
    private Instant expirationDateTime;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getQuestion() {
        return question;
    }

    public void setQuestion(String question) {
        this.question = question;
    }

    public List<Choice> getChoices() {
        return choices;
    }

    public void setChoices(List<Choice> choices) {
        this.choices = choices;
    }

    public Instant getExpirationDateTime() {
        return expirationDateTime;
    }

    public void setExpirationDateTime(Instant expirationDateTime) {
        this.expirationDateTime = expirationDateTime;
    }

    public void addChoice(Choice choice) {
        choices.add(choice);
        choice.setPoll(this);
    }

    public void removeChoice(Choice choice) {
        choices.remove(choice);
        choice.setPoll(null);
    }
}

2. Choice类（投票的选择项）

每一个Choice对象应有一个id，text，还有一个与Poll关联的外键。以下是Choice完整的代码。

package com.example.polls.model;

import javax.persistence.*;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.Size;
import java.util.Objects;

@Entity
@Table(name = "choices")
public class Choice {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @NotBlank
    @Size(max = 40)
    private String text;

    @ManyToOne(fetch = FetchType.LAZY, optional = false)
    @JoinColumn(name = "poll_id", nullable = false)
    private Poll poll;

    public Choice() {

    }

    public Choice(String text) {
        this.text = text;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }

    public Poll getPoll() {
        return poll;
    }

    public void setPoll(Poll poll) {
        this.poll = poll;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Choice choice = (Choice) o;
        return Objects.equals(id, choice.id);
    }

    @Override
    public int hashCode() {
        return Objects.hash(id);
    }
}

3.Vote类（投票）

Vote类包含了用户在哪个Poll中投了哪个Choice。以下就是完整的Vote代码。

package com.example.polls.model;

import com.example.polls.model.audit.DateAudit;
import javax.persistence.*;

@Entity
@Table(name = "votes", uniqueConstraints = {
        @UniqueConstraint(columnNames = {
                "poll_id",
                "user_id"
        })
})
public class Vote extends DateAudit {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @ManyToOne(fetch = FetchType.LAZY, optional = false)
    @JoinColumn(name = "poll_id", nullable = false)
    private Poll poll;

    @ManyToOne(fetch = FetchType.LAZY, optional = false)
    @JoinColumn(name = "choice_id", nullable = false)
    private Choice choice;

    @ManyToOne(fetch = FetchType.LAZY, optional = false)
    @JoinColumn(name = "user_id", nullable = false)
    private User user;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public Poll getPoll() {
        return poll;
    }

    public void setPoll(Poll poll) {
        this.poll = poll;
    }

    public Choice getChoice() {
        return choice;
    }

    public void setChoice(Choice choice) {
        this.choice = choice;
    }

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }
}

Repositoies

让我们为这些类定义数据仓库，从数据库中获取数据。

1. PollRepository

package com.example.polls.repository;

import com.example.polls.model.Poll;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
import java.util.List;
import java.util.Optional;

@Repository
public interface PollRepository extends JpaRepository<Poll, Long> {
    Optional<Poll> findById(Long pollId);

    Page<Poll> findByCreatedBy(Long userId, Pageable pageable);

    long countByCreatedBy(Long userId);

    List<Poll> findByIdIn(List<Long> pollIds);

    List<Poll> findByIdIn(List<Long> pollIds, Sort sort);
}

2. VoteRepository

package com.example.polls.repository;

import com.example.polls.model.ChoiceVoteCount;
import com.example.polls.model.Vote;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;
import java.util.List;

@Repository
public interface VoteRepository extends JpaRepository<Vote, Long> {
    @Query("SELECT NEW com.example.polls.model.ChoiceVoteCount(v.choice.id, count(v.id)) FROM Vote v WHERE v.poll.id in :pollIds GROUP BY v.choice.id")
    List<ChoiceVoteCount> countByPollIdInGroupByChoiceId(@Param("pollIds") List<Long> pollIds);

    @Query("SELECT NEW com.example.polls.model.ChoiceVoteCount(v.choice.id, count(v.id)) FROM Vote v WHERE v.poll.id = :pollId GROUP BY v.choice.id")
    List<ChoiceVoteCount> countByPollIdGroupByChoiceId(@Param("pollId") Long pollId);

    @Query("SELECT v FROM Vote v where v.user.id = :userId and v.poll.id in :pollIds")
    List<Vote> findByUserIdAndPollIdIn(@Param("userId") Long userId, @Param("pollIds") List<Long> pollIds);

    @Query("SELECT v FROM Vote v where v.user.id = :userId and v.poll.id = :pollId")
    Vote findByUserIdAndPollId(@Param("userId") Long userId, @Param("pollId") Long pollId);

    @Query("SELECT COUNT(v.id) from Vote v where v.user.id = :userId")
    long countByUserId(@Param("userId") Long userId);

    @Query("SELECT v.poll.id FROM Vote v WHERE v.user.id = :userId")
    Page<Long> findVotedPollIdsByUserId(@Param("userId") Long userId, Pageable pageable);
}

VoteRepository中有一些带着@Query注解的自定义查询，我使用自定义查询的原因是因为-

Spring Date JPA的动态生成查询无法满足所有查询
即使可以构建，也无法优化这些查询
于是，我们使用 JPQL constructor expression做一些查询，可以将结果返回到我们自定义的ChoiceVoteCount中。

ChoiceVoteCount

ChoiceVoteCount类就是我们用于在 VoteRepository中接收返回的自定义结果。

package com.example.polls.model;

public class ChoiceVoteCount {
    private Long choiceId;
    private Long voteCount;

    public ChoiceVoteCount(Long choiceId, Long voteCount) {
        this.choiceId = choiceId;
        this.voteCount = voteCount;
    }

    public Long getChoiceId() {
        return choiceId;
    }

    public void setChoiceId(Long choiceId) {
        this.choiceId = choiceId;
    }

    public Long getVoteCount() {
        return voteCount;
    }

    public void setVoteCount(Long voteCount) {
        this.voteCount = voteCount;
    }
}

构建Rest APIs

在构建API之前，我们需要定义各个API的入参体和返回体。

Request Payloads

1. PollRequest

package com.example.polls.payload;

import javax.validation.Valid;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import java.util.List;

public class PollRequest {
    @NotBlank
    @Size(max = 140)
    private String question;

    @NotNull
    @Size(min = 2, max = 6)
    @Valid
    private List<ChoiceRequest> choices;

    @NotNull
    @Valid
    private PollLength pollLength;

    public String getQuestion() {
        return question;
    }

    public void setQuestion(String question) {
        this.question = question;
    }

    public List<ChoiceRequest> getChoices() {
        return choices;
    }

    public void setChoices(List<ChoiceRequest> choices) {
        this.choices = choices;
    }

    public PollLength getPollLength() {
        return pollLength;
    }

    public void setPollLength(PollLength pollLength) {
        this.pollLength = pollLength;
    }
}

2.ChoiceRequest

package com.example.polls.payload;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.Size;

public class ChoiceRequest {
    @NotBlank
    @Size(max = 40)
    private String text;

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }
}

3. PollLength

package com.example.polls.payload;

import javax.validation.constraints.Max;
import javax.validation.constraints.NotNull;

public class PollLength {
    @NotNull
    @Max(7)
    private Integer days;

    @NotNull
    @Max(23)
    private Integer hours;

    public int getDays() {
        return days;
    }

    public void setDays(int days) {
        this.days = days;
    }

    public int getHours() {
        return hours;
    }

    public void setHours(int hours) {
        this.hours = hours;
    }
}

4. VoteRequest

package com.example.polls.payload;
import javax.validation.constraints.NotNull;

public class VoteRequest {
    @NotNull
    private Long choiceId;

    public Long getChoiceId() {
        return choiceId;
    }

    public void setChoiceId(Long choiceId) {
        this.choiceId = choiceId;
    }
}

Response Payloads

1. UserSummary

package com.example.polls.payload;

public class UserSummary {
    private Long id;
    private String username;
    private String name;

    public UserSummary(Long id, String username, String name) {
        this.id = id;
        this.username = username;
        this.name = name;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

2. UserIdentityAvailability

package com.example.polls.payload;

public class UserIdentityAvailability {
    private Boolean available;

    public UserIdentityAvailability(Boolean available) {
        this.available = available;
    }

    public Boolean getAvailable() {
        return available;
    }

    public void setAvailable(Boolean available) {
        this.available = available;
    }
}

3. UserProfile

package com.example.polls.payload;

import java.time.Instant;

public class UserProfile {
    private Long id;
    private String username;
    private String name;
    private Instant joinedAt;
    private Long pollCount;
    private Long voteCount;

    public UserProfile(Long id, String username, String name, Instant joinedAt, Long pollCount, Long voteCount) {
        this.id = id;
        this.username = username;
        this.name = name;
        this.joinedAt = joinedAt;
        this.pollCount = pollCount;
        this.voteCount = voteCount;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Instant getJoinedAt() {
        return joinedAt;
    }

    public void setJoinedAt(Instant joinedAt) {
        this.joinedAt = joinedAt;
    }

    public Long getPollCount() {
        return pollCount;
    }

    public void setPollCount(Long pollCount) {
        this.pollCount = pollCount;
    }

    public Long getVoteCount() {
        return voteCount;
    }

    public void setVoteCount(Long voteCount) {
        this.voteCount = voteCount;
    }
}

4. PollResponse

package com.example.polls.payload;

import com.fasterxml.jackson.annotation.JsonInclude;

import java.time.Instant;
import java.util.List;

public class PollResponse {
    private Long id;
    private String question;
    private List<ChoiceResponse> choices;
    private UserSummary createdBy;
    private Instant creationDateTime;
    private Instant expirationDateTime;
    private Boolean isExpired;

    @JsonInclude(JsonInclude.Include.NON_NULL)
    private Long selectedChoice;
    private Long totalVotes;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getQuestion() {
        return question;
    }

    public void setQuestion(String question) {
        this.question = question;
    }

    public List<ChoiceResponse> getChoices() {
        return choices;
    }

    public void setChoices(List<ChoiceResponse> choices) {
        this.choices = choices;
    }

    public UserSummary getCreatedBy() {
        return createdBy;
    }

    public void setCreatedBy(UserSummary createdBy) {
        this.createdBy = createdBy;
    }


    public Instant getCreationDateTime() {
        return creationDateTime;
    }

    public void setCreationDateTime(Instant creationDateTime) {
        this.creationDateTime = creationDateTime;
    }

    public Instant getExpirationDateTime() {
        return expirationDateTime;
    }

    public void setExpirationDateTime(Instant expirationDateTime) {
        this.expirationDateTime = expirationDateTime;
    }

    public Boolean getExpired() {
        return isExpired;
    }

    public void setExpired(Boolean expired) {
        isExpired = expired;
    }

    public Long getSelectedChoice() {
        return selectedChoice;
    }

    public void setSelectedChoice(Long selectedChoice) {
        this.selectedChoice = selectedChoice;
    }

    public Long getTotalVotes() {
        return totalVotes;
    }

    public void setTotalVotes(Long totalVotes) {
        this.totalVotes = totalVotes;
    }
}

5. ChoiceResponse

package com.example.polls.payload;

public class ChoiceResponse {
    private long id;
    private String text;
    private long voteCount;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }

    public long getVoteCount() {
        return voteCount;
    }

    public void setVoteCount(long voteCount) {
        this.voteCount = voteCount;
    }
}

6. PagedResponse

package com.example.polls.payload;

import java.util.List;

public class PagedResponse<T> {

    private List<T> content;
    private int page;
    private int size;
    private long totalElements;
    private int totalPages;
    private boolean last;

    public PagedResponse() {

    }

    public PagedResponse(List<T> content, int page, int size, long totalElements, int totalPages, boolean last) {
        this.content = content;
        this.page = page;
        this.size = size;
        this.totalElements = totalElements;
        this.totalPages = totalPages;
        this.last = last;
    }

    public List<T> getContent() {
        return content;
    }

    public void setContent(List<T> content) {
        this.content = content;
    }

    public int getPage() {
        return page;
    }

    public void setPage(int page) {
        this.page = page;
    }

    public int getSize() {
        return size;
    }

    public void setSize(int size) {
        this.size = size;
    }

    public long getTotalElements() {
        return totalElements;
    }

    public void setTotalElements(long totalElements) {
        this.totalElements = totalElements;
    }

    public int getTotalPages() {
        return totalPages;
    }

    public void setTotalPages(int totalPages) {
        this.totalPages = totalPages;
    }

    public boolean isLast() {
        return last;
    }

    public void setLast(boolean last) {
        this.last = last;
    }
}

工具类

除了请求体和返回体，我们的controllers和services还需要用到一些工具类。

1. AppConstants

package com.example.polls.util;

public interface AppConstants {
    String DEFAULT_PAGE_NUMBER = "0";
    String DEFAULT_PAGE_SIZE = "30";

    int MAX_PAGE_SIZE = 50;
}

2. ModelMapper

package com.example.polls.util;

import com.example.polls.model.Poll;
import com.example.polls.model.User;
import com.example.polls.payload.ChoiceResponse;
import com.example.polls.payload.PollResponse;
import com.example.polls.payload.UserSummary;

import java.time.Instant;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class ModelMapper {

    public static PollResponse mapPollToPollResponse(Poll poll, Map<Long, Long> choiceVotesMap, User creator, Long userVote) {
        PollResponse pollResponse = new PollResponse();
        pollResponse.setId(poll.getId());
        pollResponse.setQuestion(poll.getQuestion());
        pollResponse.setCreationDateTime(poll.getCreatedAt());
        pollResponse.setExpirationDateTime(poll.getExpirationDateTime());
        Instant now = Instant.now();
        pollResponse.setExpired(poll.getExpirationDateTime().isBefore(now));

        List<ChoiceResponse> choiceResponses = poll.getChoices().stream().map(choice -> {
            ChoiceResponse choiceResponse = new ChoiceResponse();
            choiceResponse.setId(choice.getId());
            choiceResponse.setText(choice.getText());

            if(choiceVotesMap.containsKey(choice.getId())) {
                choiceResponse.setVoteCount(choiceVotesMap.get(choice.getId()));
            } else {
                choiceResponse.setVoteCount(0);
            }
            return choiceResponse;
        }).collect(Collectors.toList());

        pollResponse.setChoices(choiceResponses);
        UserSummary creatorSummary = new UserSummary(creator.getId(), creator.getUsername(), creator.getName());
        pollResponse.setCreatedBy(creatorSummary);

        if(userVote != null) {
            pollResponse.setSelectedChoice(userVote);
        }

        long totalVotes = pollResponse.getChoices().stream().mapToLong(ChoiceResponse::getVoteCount).sum();
        pollResponse.setTotalVotes(totalVotes);

        return pollResponse;
    }
}

我们将Poll实体包装成PollResponse返回。他包含了创建调查的用户姓名，每个选项的投票数，当前用户投票的记录。这些信息都是前端需要的。

编写Rest API

我们可以controller里编写API了。

1. PollController

创建一项调查(Poll)
根据创建时间排序的调查列表
获取单个调查(Poll)
投票

PollController使用到了PollService去验证和处理一些请求。我们在下一节定义它。

package com.example.polls.controller;

import com.example.polls.model.*;
import com.example.polls.payload.*;
import com.example.polls.repository.PollRepository;
import com.example.polls.repository.UserRepository;
import com.example.polls.repository.VoteRepository;
import com.example.polls.security.CurrentUser;
import com.example.polls.security.UserPrincipal;
import com.example.polls.service.PollService;
import com.example.polls.util.AppConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
import javax.validation.Valid;
import java.net.URI;

@RestController
@RequestMapping("/api/polls")
public class PollController {

    @Autowired
    private PollRepository pollRepository;

    @Autowired
    private VoteRepository voteRepository;

    @Autowired
    private UserRepository userRepository;

    @Autowired
    private PollService pollService;

    private static final Logger logger = LoggerFactory.getLogger(PollController.class);

    @GetMapping
    public PagedResponse<PollResponse> getPolls(@CurrentUser UserPrincipal currentUser,
                                                @RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
                                                @RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size) {
        return pollService.getAllPolls(currentUser, page, size);
    }

    @PostMapping
    @PreAuthorize("hasRole('USER')")
    public ResponseEntity<?> createPoll(@Valid @RequestBody PollRequest pollRequest) {
        Poll poll = pollService.createPoll(pollRequest);

        URI location = ServletUriComponentsBuilder
                .fromCurrentRequest().path("/{pollId}")
                .buildAndExpand(poll.getId()).toUri();

        return ResponseEntity.created(location)
                .body(new ApiResponse(true, "Poll Created Successfully"));
    }

    @GetMapping("/{pollId}")
    public PollResponse getPollById(@CurrentUser UserPrincipal currentUser,
                                    @PathVariable Long pollId) {
        return pollService.getPollById(pollId, currentUser);
    }

    @PostMapping("/{pollId}/votes")
    @PreAuthorize("hasRole('USER')")
    public PollResponse castVote(@CurrentUser UserPrincipal currentUser,
                         @PathVariable Long pollId,
                         @Valid @RequestBody VoteRequest voteRequest) {
        return pollService.castVoteAndGetUpdatedPoll(pollId, voteRequest, currentUser);
    }
}

2. UserController

在 UserController，我们将编写API来完成-

获取当前登录用户
检查用户名是否被注册
检查邮箱是否被注册
获取用户的公开资料
获取指定用户创建的调查列表
获取指定用户的投票的调查列表

package com.example.polls.controller;

import com.example.polls.exception.ResourceNotFoundException;
import com.example.polls.model.User;
import com.example.polls.payload.*;
import com.example.polls.repository.PollRepository;
import com.example.polls.repository.UserRepository;
import com.example.polls.repository.VoteRepository;
import com.example.polls.security.UserPrincipal;
import com.example.polls.service.PollService;
import com.example.polls.security.CurrentUser;
import com.example.polls.util.AppConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/api")
public class UserController {

    @Autowired
    private UserRepository userRepository;

    @Autowired
    private PollRepository pollRepository;

    @Autowired
    private VoteRepository voteRepository;

    @Autowired
    private PollService pollService;

    private static final Logger logger = LoggerFactory.getLogger(UserController.class);

    @GetMapping("/user/me")
    @PreAuthorize("hasRole('USER')")
    public UserSummary getCurrentUser(@CurrentUser UserPrincipal currentUser) {
        UserSummary userSummary = new UserSummary(currentUser.getId(), currentUser.getUsername(), currentUser.getName());
        return userSummary;
    }

    @GetMapping("/user/checkUsernameAvailability")
    public UserIdentityAvailability checkUsernameAvailability(@RequestParam(value = "username") String username) {
        Boolean isAvailable = !userRepository.existsByUsername(username);
        return new UserIdentityAvailability(isAvailable);
    }

    @GetMapping("/user/checkEmailAvailability")
    public UserIdentityAvailability checkEmailAvailability(@RequestParam(value = "email") String email) {
        Boolean isAvailable = !userRepository.existsByEmail(email);
        return new UserIdentityAvailability(isAvailable);
    }

    @GetMapping("/users/{username}")
    public UserProfile getUserProfile(@PathVariable(value = "username") String username) {
        User user = userRepository.findByUsername(username)
                .orElseThrow(() -> new ResourceNotFoundException("User", "username", username));

        long pollCount = pollRepository.countByCreatedBy(user.getId());
        long voteCount = voteRepository.countByUserId(user.getId());

        UserProfile userProfile = new UserProfile(user.getId(), user.getUsername(), user.getName(), user.getCreatedAt(), pollCount, voteCount);

        return userProfile;
    }

    @GetMapping("/users/{username}/polls")
    public PagedResponse<PollResponse> getPollsCreatedBy(@PathVariable(value = "username") String username,
                                                         @CurrentUser UserPrincipal currentUser,
                                                         @RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
                                                         @RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size) {
        return pollService.getPollsCreatedBy(username, currentUser, page, size);
    }


    @GetMapping("/users/{username}/votes")
    public PagedResponse<PollResponse> getPollsVotedBy(@PathVariable(value = "username") String username,
                                                       @CurrentUser UserPrincipal currentUser,
                                                       @RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
                                                       @RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size) {
        return pollService.getPollsVotedBy(username, currentUser, page, size);
    }

}

PollService

PollController和UserController都使用到了PollService去获得PollResponse返回给客户端。

package com.example.polls.service;

import com.example.polls.exception.BadRequestException;
import com.example.polls.exception.ResourceNotFoundException;
import com.example.polls.model.*;
import com.example.polls.payload.PagedResponse;
import com.example.polls.payload.PollRequest;
import com.example.polls.payload.PollResponse;
import com.example.polls.payload.VoteRequest;
import com.example.polls.repository.PollRepository;
import com.example.polls.repository.UserRepository;
import com.example.polls.repository.VoteRepository;
import com.example.polls.security.UserPrincipal;
import com.example.polls.util.AppConstants;
import com.example.polls.util.ModelMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.stereotype.Service;
import java.time.Duration;
import java.time.Instant;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;

@Service
public class PollService {

    @Autowired
    private PollRepository pollRepository;

    @Autowired
    private VoteRepository voteRepository;

    @Autowired
    private UserRepository userRepository;

    private static final Logger logger = LoggerFactory.getLogger(PollService.class);

    public PagedResponse<PollResponse> getAllPolls(UserPrincipal currentUser, int page, int size) {
        validatePageNumberAndSize(page, size);

        // Retrieve Polls
        Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
        Page<Poll> polls = pollRepository.findAll(pageable);

        if(polls.getNumberOfElements() == 0) {
            return new PagedResponse<>(Collections.emptyList(), polls.getNumber(),
                    polls.getSize(), polls.getTotalElements(), polls.getTotalPages(), polls.isLast());
        }

        // Map Polls to PollResponses containing vote counts and poll creator details
        List<Long> pollIds = polls.map(Poll::getId).getContent();
        Map<Long, Long> choiceVoteCountMap = getChoiceVoteCountMap(pollIds);
        Map<Long, Long> pollUserVoteMap = getPollUserVoteMap(currentUser, pollIds);
        Map<Long, User> creatorMap = getPollCreatorMap(polls.getContent());

        List<PollResponse> pollResponses = polls.map(poll -> {
            return ModelMapper.mapPollToPollResponse(poll,
                    choiceVoteCountMap,
                    creatorMap.get(poll.getCreatedBy()),
                    pollUserVoteMap == null ? null : pollUserVoteMap.getOrDefault(poll.getId(), null));
        }).getContent();

        return new PagedResponse<>(pollResponses, polls.getNumber(),
                polls.getSize(), polls.getTotalElements(), polls.getTotalPages(), polls.isLast());
    }

    public PagedResponse<PollResponse> getPollsCreatedBy(String username, UserPrincipal currentUser, int page, int size) {
        validatePageNumberAndSize(page, size);

        User user = userRepository.findByUsername(username)
                .orElseThrow(() -> new ResourceNotFoundException("User", "username", username));

        // Retrieve all polls created by the given username
        Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
        Page<Poll> polls = pollRepository.findByCreatedBy(user.getId(), pageable);

        if (polls.getNumberOfElements() == 0) {
            return new PagedResponse<>(Collections.emptyList(), polls.getNumber(),
                    polls.getSize(), polls.getTotalElements(), polls.getTotalPages(), polls.isLast());
        }

        // Map Polls to PollResponses containing vote counts and poll creator details
        List<Long> pollIds = polls.map(Poll::getId).getContent();
        Map<Long, Long> choiceVoteCountMap = getChoiceVoteCountMap(pollIds);
        Map<Long, Long> pollUserVoteMap = getPollUserVoteMap(currentUser, pollIds);

        List<PollResponse> pollResponses = polls.map(poll -> {
            return ModelMapper.mapPollToPollResponse(poll,
                    choiceVoteCountMap,
                    user,
                    pollUserVoteMap == null ? null : pollUserVoteMap.getOrDefault(poll.getId(), null));
        }).getContent();

        return new PagedResponse<>(pollResponses, polls.getNumber(),
                polls.getSize(), polls.getTotalElements(), polls.getTotalPages(), polls.isLast());
    }

    public PagedResponse<PollResponse> getPollsVotedBy(String username, UserPrincipal currentUser, int page, int size) {
        validatePageNumberAndSize(page, size);

        User user = userRepository.findByUsername(username)
                .orElseThrow(() -> new ResourceNotFoundException("User", "username", username));

        // Retrieve all pollIds in which the given username has voted
        Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
        Page<Long> userVotedPollIds = voteRepository.findVotedPollIdsByUserId(user.getId(), pageable);

        if (userVotedPollIds.getNumberOfElements() == 0) {
            return new PagedResponse<>(Collections.emptyList(), userVotedPollIds.getNumber(),
                    userVotedPollIds.getSize(), userVotedPollIds.getTotalElements(),
                    userVotedPollIds.getTotalPages(), userVotedPollIds.isLast());
        }

        // Retrieve all poll details from the voted pollIds.
        List<Long> pollIds = userVotedPollIds.getContent();

        Sort sort = Sort.by(Sort.Direction.DESC, "createdAt");
        List<Poll> polls = pollRepository.findByIdIn(pollIds, sort);

        // Map Polls to PollResponses containing vote counts and poll creator details
        Map<Long, Long> choiceVoteCountMap = getChoiceVoteCountMap(pollIds);
        Map<Long, Long> pollUserVoteMap = getPollUserVoteMap(currentUser, pollIds);
        Map<Long, User> creatorMap = getPollCreatorMap(polls);

        List<PollResponse> pollResponses = polls.stream().map(poll -> {
            return ModelMapper.mapPollToPollResponse(poll,
                    choiceVoteCountMap,
                    creatorMap.get(poll.getCreatedBy()),
                    pollUserVoteMap == null ? null : pollUserVoteMap.getOrDefault(poll.getId(), null));
        }).collect(Collectors.toList());

        return new PagedResponse<>(pollResponses, userVotedPollIds.getNumber(), userVotedPollIds.getSize(), userVotedPollIds.getTotalElements(), userVotedPollIds.getTotalPages(), userVotedPollIds.isLast());
    }


    public Poll createPoll(PollRequest pollRequest) {
        Poll poll = new Poll();
        poll.setQuestion(pollRequest.getQuestion());

        pollRequest.getChoices().forEach(choiceRequest -> {
            poll.addChoice(new Choice(choiceRequest.getText()));
        });

        Instant now = Instant.now();
        Instant expirationDateTime = now.plus(Duration.ofDays(pollRequest.getPollLength().getDays()))
                .plus(Duration.ofHours(pollRequest.getPollLength().getHours()));

        poll.setExpirationDateTime(expirationDateTime);

        return pollRepository.save(poll);
    }

    public PollResponse getPollById(Long pollId, UserPrincipal currentUser) {
        Poll poll = pollRepository.findById(pollId).orElseThrow(
                () -> new ResourceNotFoundException("Poll", "id", pollId));

        // Retrieve Vote Counts of every choice belonging to the current poll
        List<ChoiceVoteCount> votes = voteRepository.countByPollIdGroupByChoiceId(pollId);

        Map<Long, Long> choiceVotesMap = votes.stream()
                .collect(Collectors.toMap(ChoiceVoteCount::getChoiceId, ChoiceVoteCount::getVoteCount));

        // Retrieve poll creator details
        User creator = userRepository.findById(poll.getCreatedBy())
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", poll.getCreatedBy()));

        // Retrieve vote done by logged in user
        Vote userVote = null;
        if(currentUser != null) {
            userVote = voteRepository.findByUserIdAndPollId(currentUser.getId(), pollId);
        }

        return ModelMapper.mapPollToPollResponse(poll, choiceVotesMap,
                creator, userVote != null ? userVote.getChoice().getId(): null);
    }

    public PollResponse castVoteAndGetUpdatedPoll(Long pollId, VoteRequest voteRequest, UserPrincipal currentUser) {
        Poll poll = pollRepository.findById(pollId)
                .orElseThrow(() -> new ResourceNotFoundException("Poll", "id", pollId));

        if(poll.getExpirationDateTime().isBefore(Instant.now())) {
            throw new BadRequestException("Sorry! This Poll has already expired");
        }

        User user = userRepository.getOne(currentUser.getId());

        Choice selectedChoice = poll.getChoices().stream()
                .filter(choice -> choice.getId().equals(voteRequest.getChoiceId()))
                .findFirst()
                .orElseThrow(() -> new ResourceNotFoundException("Choice", "id", voteRequest.getChoiceId()));

        Vote vote = new Vote();
        vote.setPoll(poll);
        vote.setUser(user);
        vote.setChoice(selectedChoice);

        try {
            vote = voteRepository.save(vote);
        } catch (DataIntegrityViolationException ex) {
            logger.info("User {} has already voted in Poll {}", currentUser.getId(), pollId);
            throw new BadRequestException("Sorry! You have already cast your vote in this poll");
        }

        //-- Vote Saved, Return the updated Poll Response now --

        // Retrieve Vote Counts of every choice belonging to the current poll
        List<ChoiceVoteCount> votes = voteRepository.countByPollIdGroupByChoiceId(pollId);

        Map<Long, Long> choiceVotesMap = votes.stream()
                .collect(Collectors.toMap(ChoiceVoteCount::getChoiceId, ChoiceVoteCount::getVoteCount));

        // Retrieve poll creator details
        User creator = userRepository.findById(poll.getCreatedBy())
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", poll.getCreatedBy()));

        return ModelMapper.mapPollToPollResponse(poll, choiceVotesMap, creator, vote.getChoice().getId());
    }


    private void validatePageNumberAndSize(int page, int size) {
        if(page < 0) {
            throw new BadRequestException("Page number cannot be less than zero.");
        }

        if(size > AppConstants.MAX_PAGE_SIZE) {
            throw new BadRequestException("Page size must not be greater than " + AppConstants.MAX_PAGE_SIZE);
        }
    }

    private Map<Long, Long> getChoiceVoteCountMap(List<Long> pollIds) {
        // Retrieve Vote Counts of every Choice belonging to the given pollIds
        List<ChoiceVoteCount> votes = voteRepository.countByPollIdInGroupByChoiceId(pollIds);

        Map<Long, Long> choiceVotesMap = votes.stream()
                .collect(Collectors.toMap(ChoiceVoteCount::getChoiceId, ChoiceVoteCount::getVoteCount));

        return choiceVotesMap;
    }

    private Map<Long, Long> getPollUserVoteMap(UserPrincipal currentUser, List<Long> pollIds) {
        // Retrieve Votes done by the logged in user to the given pollIds
        Map<Long, Long> pollUserVoteMap = null;
        if(currentUser != null) {
            List<Vote> userVotes = voteRepository.findByUserIdAndPollIdIn(currentUser.getId(), pollIds);

            pollUserVoteMap = userVotes.stream()
                    .collect(Collectors.toMap(vote -> vote.getPoll().getId(), vote -> vote.getChoice().getId()));
        }
        return pollUserVoteMap;
    }

    Map<Long, User> getPollCreatorMap(List<Poll> polls) {
        // Get Poll Creator details of the given list of polls
        List<Long> creatorIds = polls.stream()
                .map(Poll::getCreatedBy)
                .distinct()
                .collect(Collectors.toList());

        List<User> creators = userRepository.findByIdIn(creatorIds);
        Map<Long, User> creatorMap = creators.stream()
                .collect(Collectors.toMap(User::getId, Function.identity()));

        return creatorMap;
    }
}

启动应用

你可以通过以下命令启动应用

mvn spring-boot:run

（译）Spring Boot + Spring Security

创建Auditing模型

UserDateAudit

配置Auditing

业务模型

1.Vote类（发起一项民意调查的实体）

2. Choice类（投票的选择项）

3.Vote类（投票）

Repositoies

1. PollRepository

2. VoteRepository

ChoiceVoteCount

构建Rest APIs

Request Payloads

1. PollRequest

2.ChoiceRequest

3. PollLength

4. VoteRequest

Response Payloads

1. UserSummary

2. UserIdentityAvailability

3. UserProfile

4. PollResponse

5. ChoiceResponse

6. PagedResponse

工具类

1. AppConstants

2. ModelMapper

编写Rest API

1. PollController

2. UserController

PollService

启动应用

相关文章

网友评论

延伸阅读

深度阅读

栏目导航

热点阅读

前后分离

（译）Spring Boot + Spring Security

创建Auditing模型

UserDateAudit

配置Auditing

业务模型

1.Vote类 （发起一项民意调查的实体）

2. Choice类（投票的选择项）

3.Vote类（投票）

Repositoies

1. PollRepository

2. VoteRepository

ChoiceVoteCount

构建Rest APIs

Request Payloads

1. PollRequest

2.ChoiceRequest

3. PollLength

4. VoteRequest

Response Payloads

1. UserSummary

2. UserIdentityAvailability

3. UserProfile

4. PollResponse

5. ChoiceResponse

6. PagedResponse

工具类

1. AppConstants

2. ModelMapper

编写Rest API

1. PollController

2. UserController

PollService

启动应用

相关文章

网友评论

延伸阅读

深度阅读

栏目导航

热点阅读

前后分离

1.Vote类（发起一项民意调查的实体）