From 6e655b6a6d6187f1451254d13f169d78b72a8daa Mon Sep 17 00:00:00 2001
From: Matthias Kretschmann <m@kretschmann.io>
Date: Sat, 29 Sep 2018 20:09:02 +0200
Subject: [PATCH] realeted posts based on tags

---
 README.md                                     |   4 +
 ...2015-08-02-simple-tor-setup-on-mac-os-x.md |   2 +-
 src/components/atoms/Image.jsx                |   8 ++
 src/components/atoms/PostTitle.module.scss    |   9 +-
 src/components/molecules/Featured.jsx         |   4 +-
 src/components/molecules/PostMeta.jsx         |   9 +-
 src/components/molecules/RelatedPosts.jsx     | 120 ++++++++++++++++++
 .../molecules/RelatedPosts.module.scss        |  88 +++++++++++++
 src/templates/Post.jsx                        |  15 ++-
 9 files changed, 241 insertions(+), 18 deletions(-)
 create mode 100644 src/components/molecules/RelatedPosts.jsx
 create mode 100644 src/components/molecules/RelatedPosts.module.scss

diff --git a/README.md b/README.md
index b3a19230..7ae92662 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,10 @@ The whole [blog](https://kremalicious.com) is a React-based Single Page App buil
 
 ...
 
+### Related Posts
+
+...
+
 ### 🏆 SEO component
 
 Includes a SEO component which automatically switches all required `meta` tags for search engines, Twitter Cards, and Facebook OpenGraph tags based on the browsed route/page.
diff --git a/content/posts/2015-08-02-simple-tor-setup-on-mac-os-x.md b/content/posts/2015-08-02-simple-tor-setup-on-mac-os-x.md
index f3f936b3..6f696049 100644
--- a/content/posts/2015-08-02-simple-tor-setup-on-mac-os-x.md
+++ b/content/posts/2015-08-02-simple-tor-setup-on-mac-os-x.md
@@ -10,10 +10,10 @@ updated: 2018-07-11 00:52:46+02:00
 featured: true
 
 tags:
-  - goodies
   - tutorial
   - tor
   - macos
+  - goodies
 
 coinhive: true
 ---
diff --git a/src/components/atoms/Image.jsx b/src/components/atoms/Image.jsx
index 3db63015..c9889c00 100644
--- a/src/components/atoms/Image.jsx
+++ b/src/components/atoms/Image.jsx
@@ -29,4 +29,12 @@ export const imageSizeDefault = graphql`
   }
 `
 
+export const imageSizeThumb = graphql`
+  fragment ImageFluidThumb on ImageSharp {
+    fluid(maxWidth: 200, maxHeight: 85, quality: 85, cropFocus: CENTER) {
+      ...GatsbyImageSharpFluid_withWebp_noBase64
+    }
+  }
+`
+
 export default Image
diff --git a/src/components/atoms/PostTitle.module.scss b/src/components/atoms/PostTitle.module.scss
index e1a1edd3..5675f52e 100644
--- a/src/components/atoms/PostTitle.module.scss
+++ b/src/components/atoms/PostTitle.module.scss
@@ -27,15 +27,10 @@
     @include ellipsis();
 
     width: 100%;
-    text-align: center;
     color: $text-color;
     font-family: $font-family-base;
     font-size: $font-size-small;
     padding: ($spacer/4) 0;
-    max-width: 70%;
-    margin: -($spacer) auto $spacer auto;
-
-    @media (min-width: $screen-sm) {
-        max-width: 50%;
-    }
+    margin-top: -($spacer);
+    margin-bottom: $spacer;
 }
diff --git a/src/components/molecules/Featured.jsx b/src/components/molecules/Featured.jsx
index 2d35de3c..8014677e 100644
--- a/src/components/molecules/Featured.jsx
+++ b/src/components/molecules/Featured.jsx
@@ -16,9 +16,7 @@ const query = graphql`
             title
             image {
               childImageSharp {
-                fluid(maxWidth: 300, maxHeight: 130, cropFocus: CENTER) {
-                  ...GatsbyImageSharpFluid_withWebp_noBase64
-                }
+                ...ImageFluidThumb
               }
             }
           }
diff --git a/src/components/molecules/PostMeta.jsx b/src/components/molecules/PostMeta.jsx
index e1a66d0d..0897e65f 100644
--- a/src/components/molecules/PostMeta.jsx
+++ b/src/components/molecules/PostMeta.jsx
@@ -3,17 +3,14 @@ import PropTypes from 'prop-types'
 import { Link } from 'gatsby'
 import Time from 'react-time'
 import slugify from 'slugify'
-import PostLinkActions from '../atoms/PostLinkActions'
 import styles from './PostMeta.module.scss'
 
 const PostMeta = ({ post, meta }) => {
-  const { author, updated, tags, type, linkurl } = post.frontmatter
-  const { date, slug } = post.fields
+  const { author, updated, tags, type } = post.frontmatter
+  const { date } = post.fields
 
   return (
     <footer className={styles.entryMeta}>
-      {type === 'link' && <PostLinkActions slug={slug} linkurl={linkurl} />}
-
       <div className={styles.byline}>
         <span className={styles.by}>by</span>
         <a className="fn" rel="author" href={meta.author.uri}>
@@ -45,7 +42,7 @@ const PostMeta = ({ post, meta }) => {
       {tags && (
         <div className={styles.tags}>
           {tags.map(tag => {
-            const to = tag === 'goodies' ? '/goodies' : `/tag/${slugify(tag)}/`
+            const to = tag === 'goodies' ? '/goodies' : `/tags/${slugify(tag)}/`
 
             return (
               <Link key={tag} className={styles.tag} to={to}>
diff --git a/src/components/molecules/RelatedPosts.jsx b/src/components/molecules/RelatedPosts.jsx
new file mode 100644
index 00000000..da6b9ef0
--- /dev/null
+++ b/src/components/molecules/RelatedPosts.jsx
@@ -0,0 +1,120 @@
+import React, { Fragment, PureComponent } from 'react'
+import PropTypes from 'prop-types'
+import { Link, graphql, StaticQuery } from 'gatsby'
+import Image from '../atoms/Image'
+import styles from './RelatedPosts.module.scss'
+
+const query = graphql`
+  query {
+    allMarkdownRemark(sort: { order: DESC, fields: [fields___date] }) {
+      edges {
+        node {
+          id
+          frontmatter {
+            title
+            type
+            linkurl
+            tags
+            image {
+              childImageSharp {
+                ...ImageFluidThumb
+              }
+            }
+          }
+          fields {
+            slug
+            date(formatString: "MMMM DD, YYYY")
+          }
+        }
+      }
+    }
+  }
+`
+
+const postsWithDataFilter = (postsArray, key, valuesToFind) => {
+  const newArray = postsArray.filter(post => {
+    const frontmatterKey = post.node.frontmatter[key]
+
+    if (
+      frontmatterKey !== null &&
+      frontmatterKey.some(r => valuesToFind.includes(r))
+    ) {
+      return post
+    }
+  })
+  return newArray
+}
+
+const PostItem = ({ post }) => {
+  return (
+    <li>
+      <Link to={post.node.fields.slug}>
+        {post.node.frontmatter.image ? (
+          <Fragment>
+            <Image
+              fluid={post.node.frontmatter.image.childImageSharp.fluid}
+              alt={post.node.frontmatter.title}
+            />
+            <h4 className={styles.postTitle}>{post.node.frontmatter.title}</h4>
+          </Fragment>
+        ) : (
+          <div className={styles.empty}>
+            <h4 className={styles.postTitle}>{post.node.frontmatter.title}</h4>
+          </div>
+        )}
+      </Link>
+    </li>
+  )
+}
+
+PostItem.propTypes = {
+  post: PropTypes.object.isRequired
+}
+
+class RelatedPosts extends PureComponent {
+  shufflePosts = () => {
+    this.forceUpdate()
+  }
+
+  render() {
+    return (
+      <StaticQuery
+        query={query}
+        render={data => {
+          const posts = data.allMarkdownRemark.edges
+          const filteredPosts = postsWithDataFilter(
+            posts,
+            'tags',
+            this.props.tags
+          )
+
+          return (
+            <aside className={styles.relatedPosts}>
+              <h1 className={styles.title}>Related Posts</h1>
+              <ul>
+                {filteredPosts
+                  .sort(() => 0.5 - Math.random())
+                  .slice(0, 6)
+                  .map(post => (
+                    <PostItem key={post.node.id} post={post} />
+                  ))}
+              </ul>
+              <button
+                className={`${styles.button} btn`}
+                onClick={this.shufflePosts}
+              >
+                More Related Posts
+              </button>
+            </aside>
+          )
+        }}
+      />
+    )
+  }
+}
+
+RelatedPosts.propTypes = {
+  tags: PropTypes.array.isRequired
+}
+
+export default RelatedPosts
diff --git a/src/components/molecules/RelatedPosts.module.scss b/src/components/molecules/RelatedPosts.module.scss
new file mode 100644
index 00000000..7eae1b78
--- /dev/null
+++ b/src/components/molecules/RelatedPosts.module.scss
@@ -0,0 +1,88 @@
+@import 'variables';
+@import 'mixins';
+
+.empty {
+    height: 100%;
+    min-height: 80px;
+    display: flex;
+    align-items: center;
+    padding: $spacer / 4;
+
+    h4 {
+        margin-top: 0;
+    }
+}
+
+.relatedPosts {
+    margin-top: -($spacer * 2);
+    margin-bottom: $spacer;
+
+    ul {
+        display: flex;
+        flex-wrap: wrap;
+        justify-content: space-between;
+        padding: 0;
+        margin: 0;
+    }
+
+    li {
+        display: block;
+        flex: 0 0 48%;
+        margin-bottom: $spacer;
+
+        @media (min-width: $screen-sm) {
+            flex-basis: 31%;
+        }
+
+        &::before {
+            display: none;
+        }
+    }
+
+    a {
+        display: block;
+
+        > div {
+            @include media-frame;
+        }
+
+        &:hover,
+        &:focus {
+            > div {
+                border-color: $link-color;
+            }
+
+            h4 {
+                color: $link-color;
+            }
+        }
+    }
+}
+
+.title {
+    @include heading-band;
+
+    font-size: $font-size-h3;
+}
+
+.postTitle {
+    display: inline-block;
+    margin-top: $spacer / 4;
+    margin-bottom: 0;
+    font-size: $font-size-small;
+    line-height: $line-height-small;
+    color: $brand-grey-light;
+    padding-left: .2rem;
+    padding-right: .2rem;
+    transition: color .2s ease-out;
+
+    @media (min-width: $screen-md) {
+        font-size: $font-size-base;
+    }
+}
+
+.button {
+    margin: auto;
+    display: block;
+    margin-top: $spacer / 2;
+}
diff --git a/src/templates/Post.jsx b/src/templates/Post.jsx
index 3885c133..d26ebc39 100644
--- a/src/templates/Post.jsx
+++ b/src/templates/Post.jsx
@@ -8,16 +8,26 @@ import PostTitle from '../components/atoms/PostTitle'
 import PostLead from '../components/atoms/PostLead'
 import PostContent from '../components/atoms/PostContent'
 import PostActions from '../components/atoms/PostActions'
+import PostLinkActions from '../components/atoms/PostLinkActions'
 import SEO from '../components/atoms/SEO'
 import Coinhive from '../components/atoms/Coinhive'
 import PostMeta from '../components/molecules/PostMeta'
 import Exif from '../components/atoms/Exif'
+import RelatedPosts from '../components/molecules/RelatedPosts'
 import styles from './Post.module.scss'
 
 const Post = ({ data, location }) => {
   const { markdownRemark: post } = data
   const { contentYaml: meta } = data
-  const { title, image, type, linkurl, style, coinhive } = post.frontmatter
+  const {
+    title,
+    image,
+    type,
+    linkurl,
+    style,
+    coinhive,
+    tags
+  } = post.frontmatter
   const { slug } = post.fields
 
   return (
@@ -37,9 +47,12 @@ const Post = ({ data, location }) => {
           )}
           {image && image.fields && <Exif exif={image.fields.exif} />}
           <PostContent post={post} />
+          {type === 'link' && <PostLinkActions slug={slug} linkurl={linkurl} />}
           <PostActions slug={slug} url={meta.url} />
           <PostMeta post={post} meta={meta} />
         </article>
+
+        {type === 'post' && <RelatedPosts tags={tags} />}
       </Layout>
       {coinhive && <Coinhive />}
     </Fragment>