For past 38 hours now I have been learning golang and coding this. This is what this code does.
The golang code below display two post records from database in an array via json. At the moment this is the json response am getting when I run the code and is okay for now..
[
{"id":"1",
"title":"Post Title 1 ",
"content":"post content 1."
},
{"id":"2",
"title":"post Title 2 ",
"content":"post content 2 "
}
]
At the moment, postlikeCount and postunlikeCount are not fetched in the array because they reside in another table.
If everything works fine, am supposed to get an array like this which contains everything like the sample below.
[
{"id":"1",
"title":"Post Title 1 ",
"content":"post content 1.",
"postlikeCount":"2",
"postunlikeCount":"1"},
{"id":"2",
"title":"post Title 2 ",
"content":"post content 2 ",
"postlikeCount":"4",
"postunlikeCount":"0"}
]
Now to get postlikeCount and postunlikeCount, I have implemented two sect of codings below which I passed within post for rows.next() functions.
// get postlikeCount based on userid and postid
var userid =5
var postlikeCount int
err := db.QueryRow("SELECT COUNT(*) as postlikeCount FROM postData WHERE postid=? and userid=?", postid,userid).Scan(&postlikeCount)
if err != nil {
log.Fatal(err)
}
fmt.Printf("Number of postlikeCount rows are %s
", postlikeCount)
// get postunlikeCount based on userid and postid
var postunlikeCount int
err1 := db.QueryRow("SELECT COUNT(*) as postunlikeCount FROM postData WHERE postid=? and userid=?", postid,userid).Scan(&postunlikeCount)
if err1 != nil {
log.Fatal(err1)
}
fmt.Printf("Number of postunlikeCount rows are %s
", postunlikeCount)
The above two code works fine as I can Print their respective post like and unlike counts.
Here is my Issue:
When I tried to pass and append the postlikeCount and postunlikeCount parameters so that I can print them in json as per this line of code
posts = append(posts, post, postlikeCount,postunlikeCount)
It displays error
cannot postlikeCount (type int) as type post in append
cannot use postunlikeCount (type int) as type post in append
Does this error has to do with Struct function. Please can someone help me fix this. I need to pass postlikeCount and postunlikeCount as part of json as can be seen the complete array result above.
here is the full working code so far.
package main
import "database/sql"
import _ "github.com/go-sql-driver/mysql"
import "net/http"
import "fmt"
import "encoding/json"
import "log"
var db *sql.DB
var err error
type Post struct {
Id int
Title string
Content string
}
func getRecordPage1(res http.ResponseWriter, req *http.Request) {
if req.Method != "POST" {
http.ServeFile(res, req, "getjsonRecord.html")
return
}
var (
post Post
posts []Post
)
rows, err := db.Query("SELECT id,title,content FROM posts")
if err != nil {
http.Error(res, "display error, unable to select records in json", 500)
return
}
for rows.Next() {
var postid =post.Id
var title = post.Title
var content = post.Content
fmt.Printf("%s is now %d
", postid, title, content)
// get postlikeCount based on userid and postid
var userid =5
var postlikeCount int
err := db.QueryRow("SELECT COUNT(*) as postlikeCount FROM postData WHERE postid=? and userid=?", postid,userid).Scan(&postlikeCount)
if err != nil {
log.Fatal(err)
}
fmt.Printf("Number of postlikeCount rows are %s
", postlikeCount)
// get postunlikeCount based on userid and postid
var postunlikeCount int
err1 := db.QueryRow("SELECT COUNT(*) as postunlikeCount FROM postData WHERE postid=? and userid=?", postid,userid).Scan(&postunlikeCount)
if err1 != nil {
log.Fatal(err1)
}
fmt.Printf("Number of postunlikeCount rows are %s
", postunlikeCount)
rows.Scan(&post.Id, &post.Title, &post.Content)
posts = append(posts, post)
//like of code comment which causes issues
//posts = append(posts, post,postlikeCount,postunlikeCount)
}
defer rows.Close()
jsonResponse, jsonError := json.Marshal(posts)
if jsonError != nil {
fmt.Println(jsonError)
}
if jsonResponse == nil {
fmt.Println(jsonError)
} else {
res.Header().Set("Content-Type", "application/json")
res.Write(jsonResponse)
fmt.Println("Json results displayed successfully")
}
}
func homePage(res http.ResponseWriter, req *http.Request) {
http.ServeFile(res, req, "index.html")
}
func main() {
db, err = sql.Open("mysql", "root:@/golang44")
if err != nil {
panic(err.Error())
}
defer db.Close()
err = db.Ping()
if err != nil {
panic(err.Error())
}
http.HandleFunc("/getjsonRecord", getRecordPage1)
http.HandleFunc("/", homePage)
fmt.Println("Listening on 127.0.0.1:8088")
http.ListenAndServe(":8088", nil)
}
