Go Echo: POST Method gives Error "Method not allowed" - postgresql

Building an app with echo and basically created some routes.
The GET ones are working fine, but the post one is give me the error:
Do not really understand where the error lies here.
{...."method":"GET","uri":"/addPerson", message=Method Not Allowed","...."bytes_in":0,"bytes_out":33}
main.go snippet
func initEchoServer() {
e := echo.New()
e.Use(middleware.Logger())
e.Use(middleware.Recover())
// get all persons
e.GET("/persons", Info)
// get specific id
e.GET("/persons/:id", getPerson)
e.POST("/addPerson", addPerson)
e.Logger.Fatal(e.Start(viper.GetString("port")))
}
func addPerson(c echo.Context) error {
ctx := context.Background()
db, err := sql.Open("postgres", "host=postgres port=5432 user=postgres dbname=postgres password=postgres sslmode=disable")
if err != nil {
log.Fatal(err)
}
queries := postgres.New(db)
insertedPerson, err := queries.CreatePersons(ctx, postgres.CreatePersonsParams{
Firstname: "Mike",
Lastname: "Jordan",
})
if err != nil {
log.Errorf("Failed to insert a person %v", err)
return err
}
fmt.Println(insertedPerson)
return c.JSONPretty(http.StatusOK, insertedPerson, " ")
}
queries.sql.go snippet
type CreatePersonsParams struct {
Firstname string
Lastname string
}
func (q *Queries) CreatePersons(ctx context.Context, arg CreatePersonsParams) (Person, error) {
row := q.db.QueryRowContext(ctx, createPersons, arg.Firstname, arg.Lastname)
var i Person
err := row.Scan(&i.ID, &i.Firstname, &i.Lastname)
return i, err
}

you're use post method in routers
e.POST("/addPerson", addPerson)
You can use postman to hit API using POST method, don't use browser

If you register routes with POST in echo, it will only register POST method on that path. But it seems that you GET that path.
You can use e.GET().

Related

ObjectIdFromHex invalid byte error on identical strings

I'm trying to implement a FindOne method in my Golang REST API. The trouble comes where i have to search by ID. I have to convert the ID into something readable by the database, so i use primitive.ObjectIDFromHex(id)
The problem is that this method throws an error :
2021/06/19 06:56:15 encoding/hex: invalid byte: U+000A
ONLY when i call it with the id that comes from my URL GET params.
I did two versions : one with hard-coded ID, and one with GET ID. See code below.
func Admin(id string) (bson.M, error) {
coll, err := db.ConnectToCollection("admin")
if err != nil {
log.Fatal(err)
}
var admin bson.M
HardCoded := "60cb275c074ab46a1aeda45e"
fmt.Println(HardCoded) // Just to be sure : the two strings seem identical
fmt.Println(id)
objetId, err := primitive.ObjectIDFromHex(id) // throws encoding error
// objetId, err := primitive.ObjectIDFromHex(HardCoded) // Doesnt throw encoding err
if err != nil {
log.Fatal(err)
}
var ctx = context.TODO()
if err := coll.FindOne(ctx, bson.M{"_id": objetId}).Decode(&admin); err != nil {
log.Fatal(err)
}
return admin, nil
}
Of course, you'll want to know where the param id comes from.
Here you go :
func GetAdmin(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
params := mux.Vars(r)
admin, err := Admin(params["id"]) // Calling the Admin function above
if err != nil {
fmt.Println(err)
http.Error(w, err.Error(), http.StatusUnauthorized)
} else {
JSON, err := json.Marshal(admin)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
w.Write(JSON)
}
}
Trim the line feed from the end of id:
id = strings.TrimSpace(id)
Use the %q format verb when debugging issues like this. The line feed is clearly visible in this output:
fmt.Printf("%q\n", HardCoded) // prints "60cb275c074ab46a1aeda45e"
fmt.Printf("%q\n", id) // prints "60cb275c074ab46a1aeda45e\n"

Unit Testing Postgres db connection golang

I am expected to have 80% test coverage even for pushing the basic project structure. I am a bit confused how do I write unit tests for the following code to Connect to postgres db and ping postgres for health check. Can someone help me please.
var postgres *sql.DB
// ConnectToPostgres func to connect to postgres
func ConnectToPostgres(connStr string) (*sql.DB, error) {
db, err := sql.Open("postgres", connStr)
if err != nil {
log.Println("postgres-client ", err)
return nil, err
}
postgres = db
return db, nil
}
// PostgresHealthCheck to ping database and check for errors
func PostgresHealthCheck() error {
if err := postgres.Ping(); err != nil {
return err
}
return nil
}
type PostgresRepo struct {
db *sql.DB
}
// NewPostgresRepo constructor
func NewPostgresRepo(database *sql.DB) *PostgresRepo {
return &PostgresRepo{
db: database,
}
}
You need to use this : https://github.com/DATA-DOG/go-sqlmock
Its very easy to use. Here is an example where a controller is getting tested using a mocked SQL :
Implementation
func (up UserProvider) GetUsers() ([]models.User, error) {
var users = make([]models.User, 0, 10)
rows, err := up.DatabaseProvider.Query("SELECT firstname, lastname, email, age FROM Users;")
if err != nil {
return nil, err
}
for rows.Next() {
var u models.User = models.User{}
err := rows.Scan(&u.Name, &u.Lastname, &u.Email, &u.Age)
if err != nil {
return nil, err
}
users = append(users, u)
}
if err := rows.Err(); err != nil {
return nil, err
}
return users, nil
}
Test
func TestGetUsersOk(t *testing.T) {
db, mock := NewMock()
mock.ExpectQuery("SELECT firstname, lastname, email, age FROM Users;").
WillReturnRows(sqlmock.NewRows([]string{"firstname", "lastname", "email", "age"}).
AddRow("pepe", "guerra", "pepe#gmail.com", 34))
subject := UserProvider{
DatabaseProvider: repositories.NewMockDBProvider(db, nil),
}
resp, err := subject.GetUsers()
assert.Nil(t, err)
assert.NotNil(t, resp)
assert.Equal(t, 1, len(resp))
}
func NewMock() (*sql.DB, sqlmock.Sqlmock) {
db, mock, err := sqlmock.New()
if err != nil {
log.Fatalf("an error '%s' was not expected when opening a stub database connection", err)
}
return db, mock
}
I find that writing tests against a live database makes for more high quality tests. The challenge with Postgres is that there's no good in-memory fake that you can substitute in.
What I came up with is standing up the postgres Docker container and creating temporary databases in there. The PostgresContainer type in the github.com/bitcomplete/sqltestutil package does exactly this:
# Postgres version is "12"
pg, _ := sqltestutil.StartPostgresContainer(context.Background(), "12")
defer pg.Shutdown(ctx)
db, err := sql.Open("postgres", pg.ConnectionString())
// ... execute SQL
Per the docs, it's a good idea to set up your tests so that the container is only started once, as it can take a few seconds to start up (more if the image needs to be downloaded). It suggests some approaches for mitigating that problem.

Why I get an error "client disconnected" when trying to get documents from mongo collection in go?

I have mongo capped collection and a simple API, written on Go. I built and run it. When I try to sent Get request or simply go localhost:8000/logger in browser - my process closes. Debug shows this happens, while executing "find" in collection. It produces error "client is disconnected". Collection has 1 document, and debug shows it is connected with my helper.
Go version 1.13
My code:
func main() {
r := mux.NewRouter()
r.HandleFunc("/logger", getDocs).Methods("GET")
r.HandleFunc("/logger", createDoc).Methods("POST")
log.Fatal(http.ListenAndServe("localhost:8000", r))
}
func getDocs(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
var docs []models.Logger
//Connection mongoDB with helper class
collection := helper.ConnectDB()
cur, err := collection.Find(context.TODO(), bson.M{})
if err != nil {
helper.GetError(err, w)
return
}
defer cur.Close(context.TODO())
for cur.Next(context.TODO()) {
var doc models.Logger
err := cur.Decode(&doc)
if err != nil {
log.Fatal(err)
}
docs = append(docs, doc)
}
if err := cur.Err(); err != nil {
log.Fatal(err)
}
json.NewEncoder(w).Encode(docs)
}
func ConnectDB() *mongo.Collection {
client, err := mongo.NewClient(options.Client().ApplyURI("mongodb://127.0.0.1:27017"))
if err != nil {
log.Fatal(err)
}
fmt.Println("Connected to MongoDB!")
logCollection := client.Database("local").Collection("loggerCollection")
return logCollection
}
According to the documentation, the call to mongo.NewClient doesn't ensure that you can connect the Mongo server. You should first call mongo.Client.Ping() to verify if you can connect to the database or not.
client, err := mongo.NewClient(options.Client().ApplyURI("mongodb://127.0.0.1:27017"))
if err != nil {
log.Fatal(err)
}
if err := client.Ping(context.TODO(), readpref.Primary()); err != nil {
// Can't connect to Mongo server
log.Fatal(err)
}
There could be several reasons behind failing to connect, the most obvious one is incorrect setup of ports. Is your mongodb server up and listening on port 27017? Is there any change you're running mongodb with Docker and it's not forwarding to the correct port?
I faced similar issue , read #Jay answer it definitely helped , as I checked my MongoDB was running using "MongoDB Compass" , then I changed the location of my insert statement , previously I was calling before the call of "context.WithTimeout". Below is working code.
package main
import (
"context"
"log"
"time"
"go.mongodb.org/mongo-driver/mongo"
"go.mongodb.org/mongo-driver/mongo/options"
)
type Book struct {
Name string `json:"name,omitempty"`
PublisherID string `json:"publisherid,omitempty"`
Cost string `json:"cost,omitempty"`
StartTime string `json:"starttime,omitempty"`
EndTime string `json:"endtime,omitempty"`
}
func main() {
client, err := mongo.NewClient(options.Client().ApplyURI("mongodb://localhost:27017"))
if err != nil {
log.Fatal(err)
}
ctx, _ := context.WithTimeout(context.Background(), 10*time.Second)
err = client.Connect(ctx)
if err != nil {
log.Fatal(err)
}
defer client.Disconnect(ctx)
testCollection := client.Database("BooksCollection").Collection("BooksRead")
inserRes, err := testCollection.InsertOne(context.TODO(), Book{Name: "Harry Potter", PublisherID: "IBN123", Cost: "1232", StartTime: "2013-10-01T01:11:18.965Z", EndTime: "2013-10-01T01:11:18.965Z"})
log.Println("InsertResponse : ", inserRes)
log.Println("Error : ", err)
}
I can see document inserted in console as well as in "MongoDB Comapass."
In heiper function "ConnectDB" after "NewClient" I must use "client.Connect(context.TODO())"
before any other use of client

What is the bson syntax for $set in UpdateOne for the official mongo-go-driver

I am trying to get some familiarity with the official mongo-go-driver and the right syntax for UpdateOne.
My simplest full example follows:
(NOTE: in order to use this code you will need to substitute in your own user and server names as well as export the login password to the environment as MONGO_PW):
package main
import (
"context"
"fmt"
"os"
"go.mongodb.org/mongo-driver/bson"
"go.mongodb.org/mongo-driver/bson/primitive"
"go.mongodb.org/mongo-driver/mongo"
"go.mongodb.org/mongo-driver/mongo/options"
)
type DB struct {
User string
Server string
Database string
Collection string
Client *mongo.Client
Ctx context.Context
}
var db = DB{
User: <username>,
Server: <server_IP>,
Database: "test",
Collection: "movies",
Ctx: context.TODO(),
}
type Movie struct {
ID primitive.ObjectID `bson:"_id" json:"id"`
Name string `bson:"name" json:"name"`
Description string `bson:"description" json:"description"`
}
func main() {
if err := db.Connect(); err != nil {
fmt.Println("error: unable to connect")
os.Exit(1)
}
fmt.Println("connected")
// The code assumes the original entry for dunkirk is the following
// {"Name":"dunkirk", "Description":"a world war 2 movie"}
updatedMovie := Movie{
Name: "dunkirk",
Description: "movie about the british evacuation in WWII",
}
res, err := db.UpdateByName(updatedMovie)
if err != nil {
fmt.Println("error updating movie:", err)
os.Exit(1)
}
if res.MatchedCount < 1 {
fmt.Println("error: update did not match any documents")
os.Exit(1)
}
}
// UpdateByName changes the description for a movie identified by its name
func (db *DB) UpdateByName(movie Movie) (*mongo.UpdateResult, error) {
filter := bson.D{{"name", movie.Name}}
res, err := db.Client.Database(db.Database).Collection(db.Collection).UpdateOne(
db.Ctx,
filter,
movie,
)
if err != nil {
return nil, err
}
return res, nil
}
// Connect assumes that the database password is stored in the
// environment variable MONGO_PW
func (db *DB) Connect() error {
pw, ok := os.LookupEnv("MONGO_PW")
if !ok {
fmt.Println("error: unable to find MONGO_PW in the environment")
os.Exit(1)
}
mongoURI := fmt.Sprintf("mongodb+srv://%s:%s#%s", db.User, pw, db.Server)
// Set client options and verify connection
clientOptions := options.Client().ApplyURI(mongoURI)
client, err := mongo.Connect(db.Ctx, clientOptions)
if err != nil {
return err
}
err = client.Ping(db.Ctx, nil)
if err != nil {
return err
}
db.Client = client
return nil
}
The function signature for UpdateOne from the package docs is:
func (coll *Collection) UpdateOne(ctx context.Context, filter interface{},
update interface{}, opts ...*options.UpdateOptions) (*UpdateResult, error)
So I am clearly making some sort of mistake in creating the update interface{} argument to the function because I am presented with this error
error updating movie: update document must contain key beginning with '$'
The most popular answer here shows that I need to use a document sort of like this
{ $set: {"Name" : "The Matrix", "Decription" "Neo and Trinity kick butt" } }
but taken verbatim this will not compile in the mongo-go-driver.
I think I need some form of a bson document to comply with the Go syntax. What is the best and/or most efficient syntax to create this bson document for the update?
After playing around with this for a little while longer I was able to solve the problem after A LOT OF TRIAL AND ERROR using the mongodb bson package by changing the UpdateByName function in my code above as follows:
// UpdateByName changes the description for a movie identified by its name
func (db *DB) UpdateByName(movie Movie) (*mongo.UpdateResult, error) {
filter := bson.D{{"name", movie.Name}}
update := bson.D{{"$set",
bson.D{
{"description", movie.Description},
},
}}
res, err := db.Client.Database(db.Database).Collection(db.Collection).UpdateOne(
db.Ctx,
filter,
update,
)
if err != nil {
return nil, err
}
return res, nil
}
Note the use of bson.D{{$"set", .... It is unfortunate the way MongoDB has implemented the bson package this syntax still does not pass the go-vet. If anyone has a comment to fix the lint conflict below it would be appreciated.
go.mongodb.org/mongo-driver/bson/primitive.E composite literal uses unkeyed fields
In many cases you can replace construction
filter := bson.D{{"name", movie.Name}}
with
filter := bson.M{"name": movie.Name}
if arguments order dowsn't matter

Can't get Go http to return an error; 'No data recieved'

I am doing attempting to build a basic API using Go which returns the results of a SQL query using the PostgreSQL library.
At the moment I can make the program return the values, but I can't get it to return a failed message to the user i.e. some JSON with an error message.
I have an error function as follows :
func handleError(w http.ResponseWriter, err error) {
if err != nil {
log.Print(err.Error() + "\r\n") // Logging
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
}
However the http.Error method doesn't appear to ever return anything. The error thrown is a table that doesn't exist in the database (which gets logged to a text file: i.e. 2016/01/11 23:28:19 pq: relation "building_roof" does not exist
My programmes query code looks like this:
table := pq.QuoteIdentifier(table)
identifier := pq.QuoteIdentifier("ID")
rows, err := db.Query( fmt.Sprintf("SELECT %s, ST_AsText(geom) FROM %s WHERE %s = $1", identifier, table, identifier), feature)
handleError(w, err)
Causing an error just gives a Chrome error:
No data received
ERR_EMPTY_RESPONSE
EDIT Full Code:
package main
import (
"fmt"
"encoding/json"
"os"
"log"
"net/http"
"database/sql"
"strings"
"time"
"github.com/lib/pq"
)
func handler(w http.ResponseWriter, r *http.Request) {
f, err := os.OpenFile("pgdump_errorlog.txt", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)
log.Print("Couldn't open file")
defer f.Close()
log.SetOutput(f)
// Timing
start := time.Now()
// Postgres Credentials
const (
DB_USER = "postgres"
DB_PASSWORD = "OMITTED" // Removed details !
DB_PORT = "OMITTED"
DB_NAME = "OMITTED"
)
// Postgres Connect
dbinfo := fmt.Sprintf("user=%s password=%s dbname=%s port=%s sslmode=disable",
DB_USER, DB_PASSWORD, DB_NAME, DB_PORT)
db, err := sql.Open("postgres", dbinfo)
handleError(w, err)
defer db.Close()
table := r.FormValue("table")
feature := r.FormValue("id")
if table != "" {
//Postgres Query
var (
id int
geom string
)
table := pq.QuoteIdentifier(table)
identifier := pq.QuoteIdentifier("ID")
rows, qerr := db.Query( fmt.Sprintf("SELECT %s, ST_AsText(geom) FROM %s WHERE %s = $1", identifier, table, identifier), feature)
handleError(w, err)
defer rows.Close()
for rows.Next() {
err := rows.Scan(&id, &geom)
handleError(w, err)
}
err = rows.Err()
handleError(w, err)
// Maniplate Strings
returngeom := strings.Replace(geom, "1.#QNAN", "", -1)
i := strings.Index(returngeom, "(")
wkt := strings.TrimSpace(returngeom[:i])
returngeom = returngeom[i:]
type WTKJSON struct {
WTKType string
Geometry string
Elapsed time.Duration
}
returnjson := WTKJSON{Geometry: returngeom, WTKType: wkt , Elapsed: time.Since(start)/1000000.0}
json.NewEncoder(w).Encode(returnjson)
}
}
func handleError(w http.ResponseWriter, err error) {
if err != nil {
log.Print(err.Error() + "\r\n") // Logging
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
}
func main() {
http.HandleFunc("/", handler)
http.ListenAndServe(":8080", nil)
}
The following appeared to allow me to return JSON Errors:
func handleError(w http.ResponseWriter, err string) {
type APIError struct {
Error string
}
re, _ := json.Marshal(APIError{Error: err})
io.WriteString(w, string(re))
}
Used like so:
rows, err := db.Query( fmt.Sprintf("SELECT %s, ST_AsText(geom) FROM %s WHERE %s = $1", identifier, table, identifier), feature)
if err != nil {
handleError(w, err.Error())
return
}
Not suggesting this is the best method, but worked in my case.
When you are using the http.Error function the error message should a string. For simple testing I would suggest take this line
http.Error(w, err.Error(), http.StatusInternalServerError)
and change it to something like
http.Error(w,"there was an error", http.StatusInternalServerError)
and see if that response comes through. If it does its likely that you are trying to pass something that isn't a string in http.Error()