Moved the blog to new repositoryHEADmain

4 files changed, 402 insertions, 0 deletions

diff --git a/src/blog/controller.go b/src/blog/controller.go
new file mode 100644
index 0000000..8355e87
--- /dev/null
+++ b/src/blog/controller.go
@@ -0,0 +1,164 @@
+/*
+ * vidhublog: Vidhu Kant's Blog
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package blog
+
+import (
+  "strconv"
+  "fmt"
+
+	_ "github.com/go-sql-driver/mysql"
+)
+
+type Post struct {
+  ID        int
+  CreatedAt string
+  UpdatedAt *string
+  Title     string
+  Content   string
+  Tags      []Tag
+}
+
+type Tag struct {
+  ID   int
+  Name string
+}
+
+func (db *dbhandler) getPostCount(tag *int) int {
+  var query string
+  if tag != nil {
+    query = "SELECT COUNT(DISTINCT(PostID)) FROM Post_Tags WHERE TagID = " + strconv.Itoa(*tag)
+  } else {
+	// because some posts might not even have tags
+    query = "SELECT COUNT(*) FROM Posts"
+  }
+
+  rows, err := db.connection.Prepare(query)
+  if err != nil {
+    panic(err.Error())
+  }
+  defer rows.Close()
+
+  var count int
+  if err := rows.QueryRow().Scan(&count); err != nil {
+    panic(err)
+  }
+
+  return count
+}
+
+// start = read from nth row, limit = read n rows
+func (db *dbhandler) getPosts(start, limit int, reversed bool, tags string) []Post {
+  var qry string
+  if len(tags) < 1 {
+    qry = "SELECT ID, DATE_FORMAT(CreatedAt, '%D %M %Y'), Title FROM Posts"
+  } else {
+    qry = `SELECT DISTINCT Posts.ID, DATE_FORMAT(Posts.CreatedAt, '%D %M %Y'), Posts.Title
+    FROM Post_Tags 
+    INNER JOIN Posts ON Post_Tags.PostID = Posts.ID
+    WHERE Post_Tags.TagID IN (` + tags + `)`
+  }
+  if reversed {
+    qry = qry + " ORDER BY ID DESC"
+  }
+  qry = fmt.Sprintf("%s LIMIT %d,%d", qry, start, limit)
+
+  rows, err := db.connection.Query(qry) 
+  if err != nil {
+    panic(err)
+  }
+  defer rows.Close()
+
+  var posts []Post
+  for rows.Next() {
+    var p Post
+    err := rows.Scan(&p.ID, &p.CreatedAt, &p.Title)
+    if err != nil {
+      panic(err)
+    }
+    // load post's tags
+    p.Tags = db.getPostTags(p.ID)
+    posts = append(posts, p)
+  }
+
+  return posts
+}
+
+func (db *dbhandler) getPost(id int) Post {
+  rows, err := db.connection.Prepare(
+    `SELECT ID, DATE_FORMAT(CreatedAt, "%D %M %Y"), DATE_FORMAT(UpdatedAt, "%D %M %Y"), Title, Content FROM Posts WHERE ID = ?`,
+  )
+  if err != nil {
+    panic(err.Error())
+  }
+  defer rows.Close()
+
+  var post Post
+  if err := rows.QueryRow(id).Scan(&post.ID, &post.CreatedAt, &post.UpdatedAt, &post.Title, &post.Content); err != nil {
+    // TODO: handle error when rows are empty
+    post.Content = "404"
+    // panic(err)
+  }
+
+  return post
+}
+
+func (db *dbhandler) getPostTags(id int) []Tag {
+  rows, err := db.connection.Query(
+    `SELECT Tags.ID, Tags.Name FROM Post_Tags 
+    INNER JOIN Tags ON Post_Tags.TagID = Tags.ID 
+    WHERE Post_Tags.PostID = ` + strconv.Itoa(id),
+  ) 
+  if err != nil {
+		panic(err.Error())
+	}
+	defer rows.Close()
+
+  var tags []Tag
+  for rows.Next() {
+    var tag Tag
+    err := rows.Scan(&tag.ID, &tag.Name)
+    if err != nil {
+      panic(err)
+    }
+    tags = append(tags, tag)
+  }
+
+  return tags
+}
+
+// returns all tags
+func (db *dbhandler) getTags() []Tag {
+  rows, err := db.connection.Query("SELECT ID, Name FROM Tags") 
+  if err != nil {
+    panic(err.Error())
+  }
+  defer rows.Close()
+
+  var tags []Tag
+  for rows.Next() {
+    var t Tag
+    err := rows.Scan(&t.ID, &t.Name)
+    if err != nil {
+      panic(err)
+    }
+    tags = append(tags, t)
+  }
+
+  return tags
+}
diff --git a/src/blog/handler.go b/src/blog/handler.go
new file mode 100644
index 0000000..d97b24d
--- /dev/null
+++ b/src/blog/handler.go
@@ -0,0 +1,31 @@
+/*
+ * vidhublog: Vidhu Kant's Blog
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package blog
+
+import (
+	"database/sql"
+)
+
+type dbhandler struct {
+  connection *sql.DB
+}
+
+func newHandler(db *sql.DB) *dbhandler {
+  return &dbhandler{ connection: db }
+}
diff --git a/src/blog/routes.go b/src/blog/routes.go
new file mode 100644
index 0000000..c16f046
--- /dev/null
+++ b/src/blog/routes.go
@@ -0,0 +1,167 @@
+/*
+ * vidhublog: Vidhu Kant's Blog
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package blog
+
+import (
+	"html/template"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/MikunoNaka/vidhukant.xyz/db"
+	"github.com/gin-gonic/gin"
+)
+
+type tagsSelection struct {
+  TagID      int
+  TagName    string
+  IsSelected bool
+}
+
+// database connection
+var base *dbhandler
+func init() {
+  connection := db.ConnectDB()
+  base = newHandler(connection)
+}
+
+// receives tags through form POST and redirects to /posts?tags=....
+func filterByTagInput(ctx *gin.Context) {
+  var tagInput struct {
+    Tags []int `form:"tags"`
+  }
+  ctx.ShouldBind(&tagInput)
+  tags := tagInput.Tags
+
+  var tagsStringified string
+  for i, j := range tags {
+    tagsStringified = tagsStringified + strconv.Itoa(j)
+    if i != len(tags) - 1 {
+      tagsStringified = tagsStringified + ","
+    }
+  }
+
+  ctx.Redirect(http.StatusMovedPermanently, "/posts?tags=" + tagsStringified)
+}
+
+func getPosts(ctx *gin.Context) {
+  limitOptions := []int{10, 20, 30}
+  limit := 10
+  // if limit is in url query use that
+  if l := ctx.Query("limit"); l != "" {
+    limit, _ = strconv.Atoi(l)
+  }
+
+  pageNum := 1
+  // if pageNum is in url query use that
+  if p := ctx.Query("page"); p != "" {
+    pageNum, _ = strconv.Atoi(p)
+    // pageNum can't be less than 1
+    if pageNum < 1 { pageNum = 1 }
+  }
+
+  // if firstPost is in url query use that
+  firstPost := limit * (pageNum - 1)
+  if f := ctx.Query("first"); f != "" {
+    firstPost, _ = strconv.Atoi(f)
+    // firstPost can't be less than 0
+    if firstPost < 0 {firstPost = 0}
+  }
+
+  tags := ctx.Query("tags")
+
+  // check and sort by oldest/newest first with oldest as fallback
+  sortByOldest := false
+  if s := ctx.Query("sort_by"); s == "oldest" {
+    sortByOldest = true
+  }
+
+  // get posts from database
+  posts := base.getPosts(firstPost, limit, sortByOldest, tags)
+
+  showNext := true
+  // TODO: if tags are specified, replace with nil
+  // check if difference between all post count and posts shown is same
+  if base.getPostCount(nil) - (firstPost + len(posts)) < 1 {
+    showNext = false
+  }
+
+  // turn the tags from URL query into []int
+  var tagsSlice []int
+  for _, i := range strings.Split(tags, ",") {
+    t, _ := strconv.Atoi(i)
+    tagsSlice = append(tagsSlice, t)
+  }
+
+  // check if particular tags are selected
+  var selectedTags []tagsSelection
+  for _, i := range base.getTags() {
+    var t tagsSelection 
+    t.TagID = i.ID
+    t.TagName = i.Name
+
+    // check and set t.IsSelected to true
+    for _, j := range tagsSlice {
+      if t.TagID == j {
+        t.IsSelected = true
+        break
+      }
+    }
+
+    selectedTags = append(selectedTags, t)
+  }
+
+  ctx.HTML(http.StatusOK, "views/posts.html", gin.H {
+    "LimitOptions": limitOptions,
+    "Limit": limit,
+    "FirstPost": firstPost,
+    "PageNumber": pageNum,
+    "PrevPage": pageNum - 1,
+	  "ShowPrev": !(firstPost == 0),
+	  "ShowNext": showNext,
+    "NextPage": pageNum + 1,
+    "PrevFirst": firstPost - limit,
+    "NextFirst": firstPost + limit,
+    "Posts": posts,
+    "SortByOldest": sortByOldest,
+    "Tags": selectedTags,
+  })
+}
+
+func getPost(ctx *gin.Context) {
+  id, _ := strconv.Atoi(ctx.Param("id"))
+  post := base.getPost(id)
+
+  ctx.HTML(http.StatusOK, "views/post.html", gin.H {
+    "Title": post.Title,
+    "CreatedAt": post.CreatedAt,
+    "UpdatedAt": post.UpdatedAt,
+    "Content": template.HTML(post.Content),
+  })
+}
+
+func HomePage(ctx *gin.Context) {
+  recentPosts := base.getPosts(0, 10, true, "")
+  tags := base.getTags()
+
+  ctx.HTML(http.StatusOK, "views/home.html", gin.H {
+    "RecentPosts": recentPosts,
+    "Tags":        tags,
+  })
+}
diff --git a/src/blog/server.go b/src/blog/server.go
new file mode 100644
index 0000000..3b1fc17
--- /dev/null
+++ b/src/blog/server.go
@@ -0,0 +1,40 @@
+/*
+ * vidhublog: Vidhu Kant's Blog
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package blog
+
+import (
+	"github.com/gin-gonic/gin"
+)
+
+func Routes(r *gin.Engine) {
+  // load html templates
+  r.LoadHTMLGlob("web/templates/**/*")
+
+  // blog.vidhukant.xyz uses /blog as root
+  blog := r.Group("/") 
+
+  posts := blog.Group("/posts")
+
+  // fetch index page
+  posts.GET("/", getPosts)
+  posts.POST("/filter-by-tags", filterByTagInput)
+
+  // fetch a post
+  posts.GET("/:id", getPost)
+}