Django + Nuxt 实现美食分享网站（二）

从服务器获取数据

在这一部分，我们将真正实现一个全栈应用——让前端能够向后端发起请求，从而获取想要的数据。

配置 Django 的静态文件服务

首先我们要配置一下 Django 服务器，使前端能够访问其静态文件。调整 api/api/urls.py 文件如下：

api/api/urls.py

# ...
"""
from django.contrib import admin
from django.urls import path, include
[tuture-add]from django.conf import settings
[tuture-add]from django.conf.urls.static import static

urlpatterns = [
    path('admin/', admin.site.urls),
    path('api/', include('core.urls')),
[tuture-del]]
[tuture-add]] + static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

注意

这样配置静态文件路由的方式仅应当在开发环境下使用。在生产环境下（settings.py 中的 DEBUG 设为 False 时），静态文件路由将自动失效（因为 Django 并不适合作为静态文件服务器，应该选用类似 Nginx 之类的服务器，在后续教程中我们将更深入地讨论）。

实现前端的数据请求功能

在客户端，我们先要对 Nuxt 进行全局配置。Nuxt 包括 axios 包，这是一个非常出色的基于 Promise 的 HTTP 请求库。在 nuxt.config.js 中的 axios 一项中添加 Django 服务器的 URL：

client/nuxt.config.js

 // ...
  ** See https://axios.nuxtjs.org/options
  */
  axios: {
[tuture-add]    baseURL: 'http://localhost:8000/api',
  },
  /*
  ** Build configuration
  // ...

将食谱列表页面中暂时填充的假数据删去，通过 asyncData 方法获取数据。由于我们之前配置好了 axios，所以 asyncData 函数可以获取到 $axios 对象用于发起 HTTP 请求。我们实现页面加载的数据获取以及 deleteRecipe 事件，代码如下：

client/pages/recipes/index.vue

<!-- ... -->
<script>
import RecipeCard from "~/components/RecipeCard.vue";

[tuture-del]const sampleData = [
[tuture-del]  {
[tuture-del]    id: 1,
[tuture-del]    name: "通心粉",
[tuture-del]    picture: "/images/food-1.jpeg",
[tuture-del]    ingredients: "牛肉, 猪肉, 羊肉",
[tuture-del]    difficulty: "easy",
[tuture-del]    prep_time: 15,
[tuture-del]    prep_guide:
[tuture-del]      "Lorem ipsum dolor sit amet consectetur adipisicing elit. Omnis, porro. Dignissimos ducimus ratione totam fugit officiis blanditiis exercitationem, nisi vero architecto quibusdam impedit, earum "
[tuture-del]  },
[tuture-del]  {
[tuture-del]    id: 2,
[tuture-del]    name: "羊肉串",
[tuture-del]    picture: "/images/food-2.jpeg",
[tuture-del]    ingredients: "牛肉, 猪肉, 羊肉",
[tuture-del]    difficulty: "easy",
[tuture-del]    prep_time: 15,
[tuture-del]    prep_guide:
[tuture-del]      "Lorem ipsum dolor sit amet consectetur adipisicing elit. Omnis, porro. Dignissimos ducimus ratione totam fugit officiis blanditiis exercitationem, nisi vero architecto quibusdam impedit, earum "
[tuture-del]  },
[tuture-del]  {
[tuture-del]    id: 3,
[tuture-del]    name: "炒饭",
[tuture-del]    picture: "/images/banner.jpg",
[tuture-del]    ingredients: "牛肉, 猪肉, 羊肉",
[tuture-del]    difficulty: "easy",
[tuture-del]    prep_time: 15,
[tuture-del]    prep_guide:
[tuture-del]      "Lorem ipsum dolor sit amet consectetur adipisicing elit. Omnis, porro. Dignissimos ducimus ratione totam fugit officiis blanditiis exercitationem, nisi vero architecto quibusdam impedit, earum "
[tuture-del]  }
[tuture-del]];
[tuture-del] 
export default {
  head() {
    return {
      <!-- ... -->
  components: {
    RecipeCard
  },
[tuture-del]  asyncData(context) {
[tuture-del]    let data = sampleData;
[tuture-del]    return {
[tuture-del]      recipes: data
[tuture-del]    };
[tuture-add]  async asyncData({ $axios, params }) {
[tuture-add]    try {
[tuture-add]      let recipes = await $axios.$get(`/recipes/`);
[tuture-add]      return { recipes };
[tuture-add]    } catch (e) {
[tuture-add]      return { recipes: [] };
[tuture-add]    }
  },
  data() {
    return {
      <!-- ... -->
    };
  },
  methods: {
[tuture-del]    deleteRecipe(recipe_id) {
[tuture-del]      console.log(deleted`${recipe.id}`);
[tuture-add]    async deleteRecipe(recipe_id) {
[tuture-add]      try {
[tuture-add]        if (confirm('确认要删除吗？')) {
[tuture-add]          await this.$axios.$delete(`/recipes/${recipe_id}/`);
[tuture-add]          let newRecipes = await this.$axios.$get("/recipes/");
[tuture-add]          this.recipes = newRecipes;
[tuture-add]        }
[tuture-add]      } catch (e) {
[tuture-add]        console.log(e);
[tuture-add]      }
    }
  }
};
<!-- ... -->

实现食谱详情页面

我们进一步实现食谱详情页面。在 pages/recipes 目录中创建 _id 目录，在其中添加 index.vue 文件，代码如下：

client/pages/recipes/_id/index.vue

[tuture-add]<template>
[tuture-add]  <main class="container my-5">
[tuture-add]    <div class="row">
[tuture-add]      <div class="col-12 text-center my-3">
[tuture-add]        <h2 class="mb-3 display-4 text-uppercase">{{ recipe.name }}</h2>
[tuture-add]      </div>
[tuture-add]      <div class="col-md-6 mb-4">
[tuture-add]        <img
[tuture-add]          class="img-fluid"
[tuture-add]          style="width: 400px; border-radius: 10px; box-shadow: 0 1rem 1rem rgba(0,0,0,.7);"
[tuture-add]          :src="recipe.picture"
[tuture-add]          alt
[tuture-add]        >
[tuture-add]      </div>
[tuture-add]      <div class="col-md-6">
[tuture-add]        <div class="recipe-details">
[tuture-add]          <h4>食材</h4>
[tuture-add]          <p>{{ recipe.ingredients }}</p>
[tuture-add]          <h4>准备时间 ⏱</h4>
[tuture-add]          <p>{{ recipe.prep_time }} mins</p>
[tuture-add]          <h4>制作难度</h4>
[tuture-add]          <p>{{ recipe.difficulty }}</p>
[tuture-add]          <h4>制作指南</h4>
[tuture-add]          <textarea class="form-control" rows="10" v-html="recipe.prep_guide" disabled/>
[tuture-add]        </div>
[tuture-add]      </div>
[tuture-add]    </div>
[tuture-add]  </main>
[tuture-add]</template>
[tuture-add] 
[tuture-add]<script>
[tuture-add]export default {
[tuture-add]  head() {
[tuture-add]    return {
[tuture-add]      title: "食谱详情"
[tuture-add]    };
[tuture-add]  },
[tuture-add]  async asyncData({ $axios, params }) {
[tuture-add]    try {
[tuture-add]      let recipe = await $axios.$get(`/recipes/${params.id}`);
[tuture-add]      return { recipe };
[tuture-add]    } catch (e) {
[tuture-add]      return { recipe: [] };
[tuture-add]    }
[tuture-add]  },
[tuture-add]  data() {
[tuture-add]    return {
[tuture-add]      recipe: {
[tuture-add]        name: "",
[tuture-add]        picture: "",
[tuture-add]        ingredients: "",
[tuture-add]        difficulty: "",
[tuture-add]        prep_time: null,
[tuture-add]        prep_guide: ""
[tuture-add]      }
[tuture-add]    };
[tuture-add]  }
[tuture-add]};
[tuture-add]</script>
[tuture-add] 
[tuture-add]<style scoped>
[tuture-add]</style>

为了测试前端页面能否真正从后端获取数据，我们先要在后端数据库中添加一些数据，而这对 Django 来说就非常方便了。进入 api 目录，运行 python manage.py runserver 打开服务器，然后进入后台管理页面（http://localhost:8000/admin），添加一些数据：

再运行前端页面，可以看到我们刚刚在 Django 后台管理中添加的项目：

实现食谱的编辑和创建页面

有了前面的铺垫，实现食谱的添加和删除也基本上是按部就班了。我们在 pages/recipes/_id 中分别实现 edit.vue（食谱编辑页面） 和 add.vue （创建食谱页面）如下。

client/pages/recipes/_id/edit.vue

[tuture-add]<template>
[tuture-add]  <main class="container my-5">
[tuture-add]    <div class="row">
[tuture-add]      <div class="col-12 text-center my-3">
[tuture-add]        <h2 class="mb-3 display-4 text-uppercase">{{ recipe.name }}</h2>
[tuture-add]      </div>
[tuture-add]      <div class="col-md-6 mb-4">
[tuture-add]        <img v-if="!preview" class="img-fluid" style="width: 400px; border-radius: 10px; box-shadow: 0 1rem 1rem rgba(0,0,0,.7);"  :src="recipe.picture">
[tuture-add]        <img v-else class="img-fluid" style="width: 400px; border-radius: 10px; box-shadow: 0 1rem 1rem rgba(0,0,0,.7);"  :src="preview">
[tuture-add]      </div>
[tuture-add]      <div class="col-md-4">
[tuture-add]        <form @submit.prevent="submitRecipe">
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>Recipe Name</label>
[tuture-add]            <input type="text" class="form-control" v-model="recipe.name" >
[tuture-add]          </div>
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>Ingredients</label>
[tuture-add]            <input type="text" v-model="recipe.ingredients" class="form-control" name="Ingredients" >
[tuture-add]          </div>
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>Food picture</label>
[tuture-add]            <input type="file" @change="onFileChange">
[tuture-add]          </div>
[tuture-add]          <div class="row">
[tuture-add]            <div class="col-md-6">
[tuture-add]              <div class="form-group">
[tuture-add]                <label for>Difficulty</label>
[tuture-add]                <select v-model="recipe.difficulty" class="form-control" >
[tuture-add]                  <option value="Easy">Easy</option>
[tuture-add]                  <option value="Medium">Medium</option>
[tuture-add]                  <option value="Hard">Hard</option>
[tuture-add]                </select>
[tuture-add]              </div>
[tuture-add]            </div>
[tuture-add]            <div class="col-md-6">
[tuture-add]              <div class="form-group">
[tuture-add]                <label for>
[tuture-add]                  Prep time
[tuture-add]                  <small>(minutes)</small>
[tuture-add]                </label>
[tuture-add]                <input type="text" v-model="recipe.prep_time" class="form-control" name="Ingredients" >
[tuture-add]              </div>
[tuture-add]            </div>
[tuture-add]          </div>
[tuture-add]          <div class="form-group mb-3">
[tuture-add]            <label for>Preparation guide</label>
[tuture-add]            <textarea v-model="recipe.prep_guide" class="form-control" rows="8"></textarea>
[tuture-add]          </div>
[tuture-add]          <button type="submit" class="btn btn-success">Save</button>
[tuture-add]        </form>
[tuture-add]      </div>
[tuture-add]    </div>
[tuture-add]  </main>
[tuture-add]</template>
[tuture-add] 
[tuture-add]<script>
[tuture-add]export default {
[tuture-add]  head(){
[tuture-add]      return {
[tuture-add]        title: "编辑食谱"
[tuture-add]      }
[tuture-add]    },
[tuture-add]  async asyncData({ $axios, params }) {
[tuture-add]    try {
[tuture-add]      let recipe = await $axios.$get(`/recipes/${params.id}`);
[tuture-add]      return { recipe };
[tuture-add]    } catch (e) {
[tuture-add]      return { recipe: [] };
[tuture-add]    }
[tuture-add]  },
[tuture-add]  data() {
[tuture-add]    return {
[tuture-add]      recipe: {
[tuture-add]        name: "",
[tuture-add]        picture: "",
[tuture-add]        ingredients: "",
[tuture-add]        difficulty: "",
[tuture-add]        prep_time: null,
[tuture-add]        prep_guide: ""
[tuture-add]      },
[tuture-add]      preview: ""
[tuture-add]    };
[tuture-add]  },
[tuture-add]  methods: {
[tuture-add]    onFileChange(e) {
[tuture-add]      let files = e.target.files || e.dataTransfer.files;
[tuture-add]      if (!files.length) {
[tuture-add]        return;
[tuture-add]      }
[tuture-add]      this.recipe.picture = files[0]
[tuture-add]      this.createImage(files[0]);
[tuture-add]    },
[tuture-add]    createImage(file) {
[tuture-add]      let reader = new FileReader();
[tuture-add]      let vm = this;
[tuture-add]      reader.onload = e => {
[tuture-add]        vm.preview = e.target.result;
[tuture-add]      };
[tuture-add]      reader.readAsDataURL(file);
[tuture-add]    },
[tuture-add]    async submitRecipe() {
[tuture-add]      let editedRecipe = this.recipe
[tuture-add]      if (editedRecipe.picture.indexOf("http://") != -1){
[tuture-add]        delete editedRecipe["picture"]
[tuture-add]      }
[tuture-add]      const config = {
[tuture-add]        headers: { "content-type": "multipart/form-data" }
[tuture-add]      };
[tuture-add]      let formData = new FormData();
[tuture-add]      for (let data in editedRecipe) {
[tuture-add]        formData.append(data, editedRecipe[data]);
[tuture-add]      }
[tuture-add]      try {
[tuture-add]        let response = await this.$axios.$patch(`/recipes/${editedRecipe.id}/`, formData, config);
[tuture-add]        this.$router.push("/recipes/");
[tuture-add]      } catch (e) {
[tuture-add]        console.log(e);
[tuture-add]      }
[tuture-add]    }
[tuture-add]  }
[tuture-add]};
[tuture-add]</script>
[tuture-add] 
[tuture-add]<style>
[tuture-add]</style>

实现之后的页面如下：

client/pages/recipes/add.vue

[tuture-add]<template>
[tuture-add]  <main class="container my-5">
[tuture-add]    <div class="row">
[tuture-add]      <div class="col-12 text-center my-3">
[tuture-add]        <h2 class="mb-3 display-4 text-uppercase">{{ recipe.name }}</h2>
[tuture-add]      </div>
[tuture-add]      <div class="col-md-6 mb-4">
[tuture-add]        <img
[tuture-add]          v-if="preview"
[tuture-add]          class="img-fluid"
[tuture-add]          style="width: 400px; border-radius: 10px; box-shadow: 0 1rem 1rem rgba(0,0,0,.7);"
[tuture-add]          :src="preview"
[tuture-add]          alt
[tuture-add]        >
[tuture-add]        <img
[tuture-add]          v-else
[tuture-add]          class="img-fluid"
[tuture-add]          style="width: 400px; border-radius: 10px; box-shadow: 0 1rem 1rem rgba(0,0,0,.7);"
[tuture-add]          src="@/static/images/placeholder.png"
[tuture-add]        >
[tuture-add]      </div>
[tuture-add]      <div class="col-md-4">
[tuture-add]        <form @submit.prevent="submitRecipe">
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>食谱名称</label>
[tuture-add]            <input type="text" class="form-control" v-model="recipe.name">
[tuture-add]          </div>
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>食材</label>
[tuture-add]            <input v-model="recipe.ingredients" type="text" class="form-control">
[tuture-add]          </div>
[tuture-add]          <div class="form-group">
[tuture-add]            <label for>图片</label>
[tuture-add]            <input type="file" name="file" @change="onFileChange">
[tuture-add]          </div>
[tuture-add]          <div class="row">
[tuture-add]            <div class="col-md-6">
[tuture-add]              <div class="form-group">
[tuture-add]                <label for>难度</label>
[tuture-add]                <select v-model="recipe.difficulty" class="form-control">
[tuture-add]                  <option value="Easy">容易</option>
[tuture-add]                  <option value="Medium">中等</option>
[tuture-add]                  <option value="Hard">困难</option>
[tuture-add]                </select>
[tuture-add]              </div>
[tuture-add]            </div>
[tuture-add]            <div class="col-md-6">
[tuture-add]              <div class="form-group">
[tuture-add]                <label for>
[tuture-add]                  制作时间
[tuture-add]                  <small>(分钟)</small>
[tuture-add]                </label>
[tuture-add]                <input v-model="recipe.prep_time" type="number" class="form-control">
[tuture-add]              </div>
[tuture-add]            </div>
[tuture-add]          </div>
[tuture-add]          <div class="form-group mb-3">
[tuture-add]            <label for>制作指南</label>
[tuture-add]            <textarea v-model="recipe.prep_guide" class="form-control" rows="8"></textarea>
[tuture-add]          </div>
[tuture-add]          <button type="submit" class="btn btn-primary">提交</button>
[tuture-add]        </form>
[tuture-add]      </div>
[tuture-add]    </div>
[tuture-add]  </main>
[tuture-add]</template>
[tuture-add] 
[tuture-add]<script>
[tuture-add]export default {
[tuture-add]  head() {
[tuture-add]    return {
[tuture-add]      title: "Add Recipe"
[tuture-add]    };
[tuture-add]  },
[tuture-add]  data() {
[tuture-add]    return {
[tuture-add]      recipe: {
[tuture-add]        name: "",
[tuture-add]        picture: "",
[tuture-add]        ingredients: "",
[tuture-add]        difficulty: "",
[tuture-add]        prep_time: null,
[tuture-add]        prep_guide: ""
[tuture-add]      },
[tuture-add]      preview: ""
[tuture-add]    };
[tuture-add]  },
[tuture-add]  methods: {
[tuture-add]    onFileChange(e) {
[tuture-add]      let files = e.target.files || e.dataTransfer.files;
[tuture-add]      if (!files.length) {
[tuture-add]        return;
[tuture-add]      }
[tuture-add]      this.recipe.picture = files[0];
[tuture-add]      this.createImage(files[0]);
[tuture-add]    },
[tuture-add]    createImage(file) {
[tuture-add]      let reader = new FileReader();
[tuture-add]      let vm = this;
[tuture-add]      reader.onload = e => {
[tuture-add]        vm.preview = e.target.result;
[tuture-add]      };
[tuture-add]      reader.readAsDataURL(file);
[tuture-add]    },
[tuture-add]    async submitRecipe() {
[tuture-add]      const config = {
[tuture-add]        headers: { "content-type": "multipart/form-data" }
[tuture-add]      };
[tuture-add]      let formData = new FormData();
[tuture-add]      for (let data in this.recipe) {
[tuture-add]        formData.append(data, this.recipe[data]);
[tuture-add]      }
[tuture-add]      try {
[tuture-add]        let response = await this.$axios.$post("/recipes/", formData, config);
[tuture-add]        this.$router.push("/recipes/");
[tuture-add]      } catch (e) {
[tuture-add]        console.log(e);
[tuture-add]      }
[tuture-add]    }
[tuture-add]  }
[tuture-add]};
[tuture-add]</script>
[tuture-add] 
[tuture-add]<style scoped>
[tuture-add]</style>

实现的页面如下：

一点强迫症：全局页面跳转效果

在这一节中，我们将演示如何在 Nuxt 中添加全局样式文件，来实现前端页面之间的跳转效果。

首先在 assets 目录中创建 css 目录，并在其中添加 transition.css 文件，代码如下：

client/assets/css/transition.css

.page-enter-active,
.page-leave-active {
  transition: opacity .3s ease;
}

.page-enter,
.page-leave-to {
  opacity: 0;
}

在 Nuxt 配置文件中将刚才写的 transition.css 中添加到全局 CSS 中：

client/nuxt.config.js

 // ...
  ** Global CSS
  */
  css: [
[tuture-add]    '~/assets/css/transition.css',
  ],
  /*
  ** Plugins to load before mounting the App
  // ...

欧耶，一个具有完整增删改查功能、实现了前后端分离的美食分享网站就完成了！