§2023-03-01

• [Creating a Full CRUD API with Ruby Sinatra(https://dev.to/alexmercedcoder/creating-a-full-crud-api-with-ruby-sinatra-15b4)

¶Summary of RESTful Convention

• server.rb as

require 'sinatra'

## Model/Dataset

posts = [
        {title: "First Post", body: "content of first post"},
        {title: "Second Post", body: "content of second post"},
        {title: "Third Post", body: "content of third post"}
        ]


## Custom Method for Getting Request body
def getBody (req)
    ## Rewind the body in case it has already been read
    req.body.rewind
    ## parse the body
    return JSON.parse(req.body.read)
end


## Index route
get '/posts' do
    # Return all the posts as JSON
    return posts.to_json
end

## Show Route
get '/posts/:id' do
    # return a particular post as json based on the id param from the url
    # Params always come to a string so we convert to an integer
    id = params["id"].to_i
    return posts[id].to_json
end

## Create Route
post '/posts' do
    # Pass the request into the custom getBody function
    body = getBody(request)
    # create the new post
    new_post = {title: body["title"], body: body["body"]}
    # push the new post into the array
    posts.push(new_post)
    # return the new post
    return new_post.to_json
end

## Update Route
put '/posts/:id' do
    # get the id from params
    id = params["id"].to_i
    # get the request body
    body = getBody(request)
    #update the item in question
    posts[id][:title] = body["title"]
    posts[id][:body] = body["body"]
    #return the updated post
    return posts[id].to_json
end

## Destroy Route
delete '/posts/:id' do
    # get the id from params
    id = params["id"].to_i
    # delete the item
    post = posts.delete_at(id)
    # return the deleted item as json
    return post.to_json
end

• run it with rerun ruby server.rb

• test with [curl](https://www.codejava.net/rest-api/curl-for-testing-crud-rest-apis)

  • test retrieve(R)

$ curl -i localhost:4567/posts
HTTP/1.1 200 OK
Content-Type: text/html;charset=utf-8
Content-Length: 165
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
Connection: keep-alive
Server: thin

[{"title":"First Post","body":"content of first post"},{"tille":"Second Post","body":"content of second post"},{"tille":"Third Post","body":"content of third post"}] 

$ curl -v localhost:4567/posts/1
*   Trying 127.0.0.1:4567...
* connect to 127.0.0.1 port 4567 failed: Connection refused
*   Trying [::1]:4567...
* Connected to localhost (::1) port 4567 (#0)
> GET /posts/1 HTTP/1.1
> Host: localhost:4567
> User-Agent: curl/7.87.0
> Accept: */*
> 
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Content-Type: text/html;charset=utf-8
< Content-Length: 55
< X-XSS-Protection: 1; mode=block
< X-Content-Type-Options: nosniff
< X-Frame-Options: SAMEORIGIN
< Connection: keep-alive
< Server: thin
< 
* Connection #0 to host localhost left intact
{"tille":"Second Post","body":"content of second post"}

$ curl -X POST -H "Content-Type: application/json" -d "{\"tille\": \"Fourth Post\", \"body\": \"content of fourth post\"}" localhost:4567/posts
{"title":null,"body":"content of fourhttp://localhost:4567/posts

$ curl http://localhost:4567/posts
[{"title":"First Post","body":"content of first post"},{"title":"Second Post","body":"content of second post"},{"title":"Third Post","body":"content of third post"},{"title":null,"body":"content of fourth post"}]

$  curl -X DELETE http://localhost:4567/posts/0
{"title":"First Post","body":"co

$ curl localhost:4567/posts
[{"title":"Second Post","body":"content of second post"},{"title":"Third Post","body":"content of third post"},{"title":null,"body":"content of fourth post"}]

$ curl -X PUT -H "Content-Type: application/json" -d "{\"title\": \"Fourth Post\", \"body\": \"content of fourth post\"}" localhost:4567/posts/2
{"title":"Fourth Post","body":"content of fourth post"}

- test Create with `curl -H`

curl -X POST -H "Content-Type: application/json" -d "{"title": "Fourth Post", "body": "content of fourth post"}" localhost:4567/posts/

curl -X PUT -H "Content-Type: application/json" -d "{"title": "Fourth Post", "body": "content of fourth post"}" localhost:4567/posts/2

                                        {\"tille\": \"Fourth Post\", \"body\": \"content of fourth post\"}

curl -X POST -i -d "userId=10&title=Hello World&body=This is the body." https://jsonplaceholder.typicode.com/posts

curl -d 'id=1&name=create' http://localhost:8080/new

curl -X POST -i -d "title=Fourth Post&body=content of fourth post" http://localhost:4567/posts

curl -X DELETE http://localhost:4567/posts/0