I'm checking out amazon simpledb documentation. They mention only server si开发者_开发百科de languages.
Is there anyway to insert data into the db directly from the client side without going through a server?
If not, how come?
Yes and no. Since you need to protect your secret key for AWS (hackers could use it to abuse your account), you can't authenticate requests in JS directly.
While you could create an implementation in JS, it would be inherently insecure. Practical for some internal uses, it could never be safely deployed (as that would expose your secret key). What you could do instead is use your server to authenticate the requests to SimpleDB and let the JS perform the actual request to Amazon. Though it's a bit roundabout, it would work.
The downside is that you'd need to do a bunch of processing on the client side. You're also likely fetching more data than your app consumes/outputs, so processing the data on the client instead of on the server would likely encounter more latency simply because you're transferring more data to the user and processing it more slowly.
Hope this helps
If not, how come?
Security. You authenticate to the DB with your developer account. Amazon does not know about your end users (which it would need to, in order to authenticate access directly from the browser). It is up to the application code to determine what end users are allowed to do and what not.
That said, there is the Javascript Scratchpad for Amazon SimpleDB sample application. It does access SimpleDB directly from the browser (you have to type in your AWS credendials).
SimeplDBAdmin is a Javascript/PHP based interface:
http://awsninja.com/2010/07/08/simpledbadmin-a-phpmyadmin-like-interface-for-amazon-simpledb/
The PHP side is a relay script[relay.php] which will pass the requests made from the Javascript client and send them on to the server, takes the response from the server and reformats it for the client. This is to easily get around the cross-domain problems with Javascript[if the web client had downloaded the web page containing the javascript code from www.example.com it will only allow javascript to connect back to www.example.com by default].
Everything else, including request signing, is done by the Javascript code.
Also note that Amazon has released a new beta service recently to allow you to setup sub-accounts under your Amazon account. The simpleDB protection is very basic[either on or off per account] but as it does provide some limited form of request tracking, it could be argued that using Javascript and giving each user their OWN userid and key for request signing is MORE secure. Having every user use the SAME userid and certificate would, of course, be insecure.
There is a free, pure JavaScript interface available. Please see https://chrome.google.com/webstore/detail/ddhigekdfabonefhiildaiccafacphgg
See this answer to the similar question on allowing secure, anonymous, read-only access to SimpleDB from untrusted clients: anonymous read with amazon simpledb .
Some variations from that answer:
- don't set access policy to read-only. However, it allows fine grained control, so you may still wish to limit the kind of writes allowed
- don't be anonymous. The AWS docs on token based auth and example apps show parallel paths: anonymous access or non-anonymous AWS/federated access with your credentials but without exposing your secret key.
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