I've been looking around at various APIs, and since twitter seems to be a common discussion point, I'll use it as an example.
A lot of APIs are implementing oAuth which is great for allowing the service to authenicate and authorize the application connecting to it, however, from what I have seen there doesnt seem to be a way for the application to verify that Twitter is actually Twitter (and not a man in the middle based attack)? I would expect to see some kind of signature (using a shared / public key) of the response body which I can use to validate that twitter signed it.
Is it just because currently there isnt really a point to a man in the middle attack with twitter tweets since currently, whats the worst that can happen (and why would someone want to give me invalid tweets)
On this point, if you were to sign the response, what method would you use? Im currently considering a HMAC-SHA1 signature of the response body using a shared key.
This is what the 'trust' part of SSL does.
-- Edit
I note this has been downvoted, but it's important that other readers realise it's due to a personal disagreement, not due to incorrectness.
In the .NET world we use WCF, which has many different security models, including signing (and if desired encrypting) each message/response. This adds up to a non-trivial amount of overhead, but can give you more 'trust' in the security model. You can switch to using binary-serialized data to cut down on the bloat and message size if you desire.
I'm not sure what other Web Service APIs offer in that area, though I'm sure someone else can add further details as needed.
Related
My aim is to select some text from a web page, start a google chrome extension and give the text to a google cloud api (Natural Language API) in my case.
I want to do some sentimental analysis and then get back the result to mark/ highlight positive sentences in green and negative ones in red.
I am new to this and do not know how to start.
The extension consists of manifest, popup etc. How should I call an API from there that does Natural Language Processing?
Should I create a Google Cloud Application with an API_KEY to call? In that case I would have to upload my credentials right?
Sorry sounds a bit confusing I know but I just don't know how I can bring this 2 things together an would be more than happy about any help
The best way to authenticate your app will depend on the specific needs and use cases of your application. You can see an overview of all the different methods here.
If you are not planning on identifying users nor on using a back end server that handles authenticating (as I assume to be your case), the best option would indeed be to use API keys. They do not identify the user, but are enough for the Natural Language APIs.
To do this you will need to create an API key for the services you want and add the necessary restrictions to make the key as secure as possible. Detailed instructions on how to do this and how to use the key in a url can be found here.
The API call could be made from within the Chrome extension with any JavaScript method capable of performing POST requests. For example using XMLHttpRequest or the Fetch API. You can find an example of the parameters that need to be included in the request here.
You may run into CORS issues when making the request directly from the extension. I recommend reading this answer, where a couple of workarounds for these issues are suggested.
How to get the API key for the authentication purposes for posting the request to get the email previews using Litmus?
There are actually a few different Litmus Preview APIs to cater to different use cases. We're in the process of simplifying this, partly in the hope of making the experience for a new API user a little more obvious.
If you reach out to hello#litmus.com we'll direct you to the appropriate API version and how to obtain your key.
I really don't understand this OAuth authentication method, so I just gave up. The reason I decided to create my own was because I believe the functions my API will carry out aren't that big, it'll mostly be able to read data and occasionally write too.
Here's my plan for API requests on my site.
Consumer API Request with a special key > User Authorise's Application (if not done so already) > Callback URL to consumer upon authorising > Run API Script on provider > return result to consumer.
Is this okay? This is my first time writing an API for any site, so I'm here to learn.
In general, I would say that if you're trying to roll your own authentication protocol because you don't understand the existing ones, you're making a Fatal Mistake™.
The only time you should consider doing this is if you totally understand the protocol in question, and require some functionality from it that you are 100% sure it does not offer. OAuth is complicated because it has to be. Certain requirements exist to make sure it's secure.
In writing your own without understanding the complexity, you're setting yourself up to fail.
I have a website that revolves around transactions between two users. Each user needs to agree to the same terms. If I want an API so other websites can implement this into their own website, then I want to make sure that the other websites cannot mess with the process by including more fields in between or things that are irrelevant to my application. Is this possible?
If I was to implement such a thing, I would allow other websites to use tokens/URLs/widgets that would link them to my website. So, for example, website X wants to use my service to agree user A and B on the same terms. Their page will have an embedded form/frame which would be generated from my website and user B will also receive an email with link to my website's page (or a page of website X with a form/frame generated from my server).
Consider how different sites use eBay to enable users to pay. You buy everything on the site but when you are paying, either you are taken to ebay page and come back after payment, or the website has a small form/frame that is directly linked to ebay.
But this is my solution, one way of doing it. Hope this helps.
It depends on how your API is implemented. It takes considerably more work, thought, and engineering to build an API that can literally take any kind of data or to build an API that can take additional, named, key/value pairs as fields.
If you have implemented your API in this manner, then it's quite possible that users of this API could use it to extend functionality or build something slightly different by passing in additional data.
However, if your API is built to where specific values must be passed and these fields are required, then it becomes much more difficult for your API to be used in a manner that differs from what you originally intended.
For example, Google has many different API's for different purposes, and each API has a very specific number of required parameters that a developer must use in order to make a successful HTTP request. While the goal of these API's are to allow developers to extend functionality, they do allow access to only very specific pieces of data.
Lastly, you can use authentication to prevent unauthorized access to your API. The specific implementation details depend largely on the platform you're working with as well as how the API will be used. For instance, if users must login to use services provided by your API, then a form of OAuth may suffice. However, if other servers will consume your API, then the authorization will have to take place in the HTTP headers.
For more information on API best practices, see 7 Rules of Thumb When You Build an API, and a slideshow from a Google Engineer titled How to Design a Good API and Why That Matters.
What things should a developer designing and implementing an API for a community based website know before starting the heavy coding? There are a bunch of APIs out there like Twitter API, Facebook API, Flickr API, etc which are all good examples. But how would you build your own API?
What technologies would you use? I think it's a good idea to use REST-like interface so that the API is accessible from different platforms/clients/browsers/command line tools (like curl). Am I right? I know that all the principles of web development should be met like caching, availability, scalability, security, protection against potential DOS attacks, validation, etc. And when it comes to APIs some of the most important things are backward compatibility and documentation. Am I missing something?
On the other hand, thinking from user's point of view (I mean the developer who is going to use your API), what would you look for in an API? Good documentation? Lots of code samples?
This question was inspired by Joel Coehoorn's question "What should a developer know before building a public web site?".
This question is a community wiki, so I hope you will help me put in one place all the things that should be addressed when building an API for a community based website.
If you really want to define a REST api, then do the following:
forget all technology issues other than HTTP and media types.
Identify the major use cases where a client will interact with the API
Write client code that perform those "use cases" against a hypothetical HTTP server. The only information that client should start with is the response from a GET request to the root API url. The client should identify the media-type of the response from the HTTP content-type header and it should parse the response. That response should contain links to other resources that allow the client to perform all of the APIs required operations.
When creating a REST api it is easier to think of it as a "user interface" for a machine rather than exposing an object model or process model. Imagine the machine navigating the api programmatically by retrieving a response, following a link, processing the response and following the next link. The client should never construct a URL based on its knowledge of how the server organizes resources.
How those links are formatted and identified is critical. The most important decision you will make in defining a REST API is your choice of media types. You either need to find standard ways of representing that link information (think Atom, microformats, atom link-relations, Html5 link relations) or if you have specialized needs and you don't need really wide reach to many clients, then you could create your own media-types.
Document how those media types are structured and what links/link-relations they may contain. Specific information about media types is critical to the client. Having a server return Content-Type:application/xml is useless to a client if it wants to do anything more than parse the response. The client cannot know what is contained in a response of type application/xml. Some people do believe you can use XML schema to define this but there are several disadvantages to this and it violates the REST "self-descriptive message" constraint.
Remember that what the URL looks like has absolutely no bearing on how the client should operate. The only exception to this, is that a media type may specify the use of templated URIs and may define parameters of those templates. The structure of the URL will become significant when it comes to choosing a server side framework. The server controls the URL structure, the client should not care. However, do not let the server side framework dictate how the client interacts with the API and be very cautious about choosing a framework that requires you to change your API. HTTP should be the only constraint regarding the client/server interaction.