flask

Question 1

Flask: To import the flask class, type

Answer 1

from flask import Flask

Question 2

Flask: To create an instance of the Flask class, type

Answer 2

app = Flask(__name__)

Question 3

Flask: To make an app run but automatically use changes to the server code, type

Answer 3

app.run(debug=True)

Question 4

Flask: To create the route for an app, type

Answer 4

@app.route("/")
def index():
  return "This is my route"

Question 5

Flask: To import the request library, type

Answer 5

form flask import request

Answer 6

@app.route("/")
def index(name_var="Default Name"):
    name = request.args.get("name", name_var)
    return name
note: .get returns either the value on query string and if none present, returns whatever is after the comma.

Answer 7

Yes e.g.

@app.route(“/route_one”)
@app.route(“/route_two”)

Answer 8

from flask import Flask

app = Flask(__name__)

@app.route("//")
def my_function(name, age):
    return "Im {}, {}".format(name, age)

Question 9

Flask: Values pulled from the url are automatically the type

Answer 9

string

Answer 10

name the parameter in the function the same as what you are naming the url slash index, e.g.

@app.route("/")
def my_function(name):
    return "Im {}".format(age)

Question 11

Flask: To run a flask app on the local host, type

Answer 11

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello World!'

if __name__ == ‘__main__’:
app.run()

Then save it and run it in python from the command line.

Question 12

Flask: Triple quotes allow you to

Answer 12

Use line breaks by pressing enter

Question 13

Flask: Flask automatically looks for a directory in the same directory as the app called

Answer 13

Templates. And it will automatically serve whats in it when you reference templates in your view.

Question 14

Flask: To import templates in the app, type

Answer 14

from flask import render_template

Question 15

Flask: To make a view return a template and pass it the variables, type

Answer 15

@app.route("/")
def my_function():
    return render_template("name.html", var_1=name, var_2=age)

Question 16

Flask: When making views, make sure to always

Answer 16

pass in all of the variables you declare in the view.

Question 17

Flask: To make the html template pull variables from the view, type

Answer 17

{{ var_name }}

Question 18

Flask: html templates can be altered in just a small portion, by changing a

Answer 18

block

Question 19

Flask: To imbed blocks inside the html templates, type

Answer 19

{% block block_name %}{% endblock %}

Question 20

Flask: To create an extends html block, type

Answer 20

{% extends “layout.html” %}

Question 21

Flask: The extends block

Answer 21

Imports all of the html of the file you link to except what is contained in the blocks which you need to replace with your own block contents (using the same block names).

Question 22

Flask: To use the contents of a block from the html file you are extending, type

Answer 22

{{ super() }}

Question 23

Flask: Static files should be saved in

Answer 23

A directory called “static” in the same directory as the app.

Question 24

Flask: An example of a static file that goes in the static directory is

Answer 24

styles.css, javascript, images

Question 25

Flask: using __name__, passes in

Answer 25

the current namespace.

Question 26

Flask: The request object holds an attribute called

Answer 26

request.args

Question 27

Flask: args holds all of the

Answer 27

parameters in the request (url) in a dictionary

Question 28

Flask: To retrieve an object from the url request and set it to a variable, type

Answer 28

my_var = request.args.get("parameter value", "default")

Question 29

Flask: to accept a url request with and take the value into the view function, type

Answer 29

``` @app.route("/-parameter_value>") def index(paramer_value="yo"): return "hello {}".format(parameter_value) ```

Question 30

flask: To turn values coming in from a request into integers, make the route

Answer 30

app.route("/-int:assigned_variable>")

Question 31

flask: flask view functions (in order to work properly) can only return a

Answer 31

string

Question 32

flask: flask views can have multiple

Answer 32

routes which can accept request values in all of the arrangements they may come in. app. route("/-int:num1>/-float:num2>" app. route("/-float:num1>/-int:num2>"

Question 33

Flask: for a basic flask app with two views, multiple routes, and character conversion, type

Answer 33

from flask import Flask from flask import request app = Flask(__name__) ``` @app.route("/") def index(parameter_value="default"): parameter_value = request.args.get("sent in value", parameter_value) return "hello {}".format(parameter_value) ``` @app.route("/add//") @app.route("/add//") def add(num1, num2): return "sum {}".format(num1+num2) app.run(debug=True)

Question 34

flask: To send a dataframe to an layout in html format, type

Answer 34

``` app.route("/analysis") def analysis(): df = pandas.DataFrame() return render_template("analysis.html", data=df.to_html()) ``` {% extends "layout.html" %} {% block body %} {{ data | safe }} {% endblock %}

Question 35

python: To find the files you just installed through pip

Answer 35

lib/python2.7/site-packages/module_name.egg/

Question 36

python: It seems that if you have multiple files inside one module you can just

Answer 36

import a class straight from the module and do not have to go into the specific file in the module

Question 37

flask: To use minimongo through flask, type

Answer 37

from flask import Flask, render_template, request from minimongo import Model, configure app = Flask(__name__) configure(host="ds029824.mongolab.com", port=29824, username="al", password="al") ``` class collectionDocument(Model): class Meta: database = "databaseName" collection = "collectionName" ``` @app.route('/') def hello_world(): instance = collectionDocument() instance.hello = request.args.get("key") instance.save() instance = collectionDocument({"x": 1, "y": 2}).save() collectionDocument.collection.find_one() instance = collectionDocument.collection.find_one({"x": 1}) return 'String!'

Question 38

flask: To convert a request object into json format, type

Answer 38

request.get_json()

Question 39

flask: To get a field from a post request, type

Answer 39

request.form.get("field_name")

Question 40

flask: To turn an array of dicts into a json response, tyep

Answer 40

from flask import jsonify ... return jsonify(data = [{"key":"value"}, {"key2":"value2"}]) note:key-name (e.g. data) is required

Question 41

flask: To make static files serve from flask paths

Answer 41

from flask import Flask, request, send_from_directory ``` @app.route('/') def send_static(path): return send_from_directory('static', path) ```

Question 42

flask: To allow post and get requests, type

Answer 42

@app.route('/', methods=['GET', 'POST']) def view_function(): if request.method == 'POST': ...

Question 43

flask: To get a file from a post request, type

Answer 43

request.files.get("file_name")