JNaeemGitonga

Perl and PHP Regular Expressions

PHP regexes are based on the PCRE (Perl-Compatible Regular Expressions), so any regexp that works for one should be compatible with the other or any other language that makes use of the PCRE format. Here are some commonly needed regular expressions for both PHP and Perl. Each regex will be in string format and will include delimiters.
All Major Credit Cards

This regular expression will validate all major credit cards: American Express (Amex), Discover, Mastercard, and Visa.

    //All major credit cards regex
    '/^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6011[0-9]{12}|622((12[6-9]|1[3-9][0-9])|([2-8][0-9][0-9])|(9(([0-1][0-9])|(2[0-5]))))[0-9]{10}|64[4-9][0-9]{13}|65[0-9]{14}|3(?:0[0-5]|[68][0-9])[0-9]{11}|3[47][0-9]{13})*$/'

JNaeemGitonga

export GOPATH=$HOME/porjects/go
export PATH="$PATH:$HOME/projects/go/bin"

JNaeemGitonga

type Story struct {
	ID      primitive.ObjectID `json:"_id,omitempty" bson:"_id,omitempty"`
	Author  string             `json:"author,,omitempty" bson:"author,,omitempty"`
	Title   string             `json:"title,,omitempty" bson:"title,,omitempty"`
	Content string             `json:"content,,omitempty" bson:"content,,omitempty"`
	Likes   int                `json:"likes,,omitempty" bson:"likes,,omitempty"`
}

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func updateStory(ctx context.Context, update string) (events.APIGatewayProxyResponse, error) {
	var raw Story // <--- this line and the following two are important here because if we didn't do this
	data := []byte(update) // we wouldn't be able to use the incoming data as is since it is of type `string`.
	if err := json.Unmarshal(data, &raw); err != nil {
		handleError(err)
	}

	filter := bson.D{{"_id", raw.ID}} // <-- this is how we access those objects
	upDate := bson.D{{"$set", bson.D{{"likes", raw.Likes}}}}
	result, err := collection.UpdateOne(ctx, filter, upDate)

JNaeemGitonga

func postStory(ctx context.Context, story string) (events.APIGatewayProxyResponse, error) {
	err := client.Ping(ctx, readpref.Primary())
	if err != nil {
		return handleError(err)
	}

	var raw Story // <--- this and the folowing two lines was a big gotcha 
	s := strings.NewReader(story) // ^---> because the type of response.Body is `string` and you need it 
	json.NewDecoder(s).Decode(&raw) // ^---> to be what's defined in your schema/json

JNaeemGitonga

func marshalJSONAndSend(res []Story) (events.APIGatewayProxyResponse, error) {
	response, err := json.Marshal(res)
	if err != nil {
		return handleError(err)
	}
	return events.APIGatewayProxyResponse{
		Body:       string(response),
		StatusCode: 200,
	}, nil
}

JNaeemGitonga

/*
	handleResultSendDbResponse is used to handle multiple db responses
	from insert and update operations it can also be extended to handle
	delete operations when we are ready to add that functionality to the
	API
*/
func handleResultSendDbResponse(whichType string) (events.APIGatewayProxyResponse, error) {
	/*
		you have to use reflect to dynamically get a value from a struct as
		I am doing below. I used a struct so that I could reuse some code

JNaeemGitonga

func handleError(err error) (events.APIGatewayProxyResponse, error) {
	return events.APIGatewayProxyResponse{
		Body:       err.Error(),
		StatusCode: 502,
	}, err
}

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func getStories(ctx context.Context) (events.APIGatewayProxyResponse, error) {
	err := client.Ping(ctx, readpref.Primary())
	if err != nil {
		return handleError(err)
	}

	cursor, err := collection.Find(ctx, bson.D{})
	defer cursor.Close(ctx)

	if err != nil {

JNaeemGitonga

func defaultReturn() (events.APIGatewayProxyResponse, error) {
	return events.APIGatewayProxyResponse{
		Body:       "whatever you did, it worked!",
		StatusCode: 200,
	}, nil
}