verifyHandler.go

package main

import (
    "encoding/json"
    "fmt"
    "net/http"
    "strconv"
    "strings"
)

func verifyHandler(w http.ResponseWriter, r *http.Request) {
    decoder := json.NewDecoder(r.Body)
    Req := struct {
        Token       string `json:"token"`
        PhoneNumber string `json:"phone_number"`
        FirebaseID  string `json:"firebase_id"`
    }{"", "", ""}
    err := decoder.Decode(&Req)

    if err != nil {
        failWithStatusCode(err, http.StatusText(http.StatusBadRequest), w, http.StatusBadRequest)
        return
    }

    if Req.Token == "" || Req.PhoneNumber == "" || Req.FirebaseID == "" {
        w.WriteHeader(http.StatusBadRequest)
        fmt.Fprintf(w, "Bad request")
        return
    }

    Req.PhoneNumber = strings.Replace(Req.PhoneNumber, "-", "", -1)
    _, err = strconv.Atoi(Req.PhoneNumber)
    if (err != nil) || (len(Req.PhoneNumber) < 10 || len(Req.PhoneNumber) > 16) {
        failWithStatusCode(err, http.StatusText(http.StatusBadRequest), w, http.StatusBadRequest)
        return
    }

    User := struct {
        FirstName   string
        LastName    string
        PhoneNumber string
        Token       string
    }{"", "", "", ""}

    queryString := "SELECT first_name, last_name, phone_number, token FROM temp_users WHERE phone_number = $1"
    stmt, err := db.Prepare(queryString)

    if err != nil {
        failWithStatusCode(err, http.StatusText(http.StatusInternalServerError), w, http.StatusInternalServerError)
        return
    }

    err = stmt.QueryRow(Req.PhoneNumber).Scan(&User.FirstName, &User.LastName, &User.PhoneNumber, &User.Token)

    if User.Token == "" {
        failWithStatusCode(err, "Attempting to verify user that does not exist", w, http.StatusNotFound)
        return
    }

    if Req.Token == User.Token {
        queryString =   "INSERT INTO users(first_name, last_name, phone_number, current_status, api_token, firebase_id) " +
                        "VALUES($1, $2, $3, $4, $5, $6)" +
                        "ON CONFLICT (phone_number) DO UPDATE " +
                        "SET first_name = $1, last_name = $2, current_status = $4, api_token = $5, firebase_id = $6 " +
                        "WHERE EXCLUDED.phone_number = $3"
        stmt, err = db.Prepare(queryString)
        if err != nil {
            failWithStatusCode(err, "Error preparing query", w, http.StatusInternalServerError)
            return
        }
        var apiToken = randString(16)
        res, err := stmt.Exec(User.FirstName, User.LastName, User.PhoneNumber, "active", apiToken, Req.FirebaseID)
        if err != nil {
            failWithStatusCode(err, "Error Inserting User", w, http.StatusInternalServerError)
            return
        }
        numRows, err := res.RowsAffected()
        if numRows < 1 {
            failWithStatusCode(err, "Error Inserting User", w, http.StatusConflict)
            return
        }

        queryString = "DELETE FROM temp_users WHERE phone_number = $1"
        stmt, err = db.Prepare(queryString)
        if err != nil {
            failWithStatusCode(err, "Error preparing query", w, http.StatusInternalServerError)
            return
        }
        res, err = stmt.Exec(Req.PhoneNumber)
        if err != nil {
            failWithStatusCode(err, "Problem deleting temp entry", w, http.StatusInternalServerError)
            return
        }
        numRows, err = res.RowsAffected()
        if numRows < 1 {
            failWithStatusCode(err, "Problem deleting temp entry", w, http.StatusInternalServerError)
            return
        }
        w.WriteHeader(http.StatusOK)
        fmt.Fprintf(w, "{\"api_token\":\"%s\"}", apiToken)

    } else {
        failWithStatusCode(err, "Token does not match", w, http.StatusUnauthorized)
    }
}