The question may sound a bit stupid but I think it's interesting. Is it possible to upload a GAE application (java or python) from another GAE application ? I mean to use the first GAE app purely as a build server (e.g. http://www.atlassian.com/software/bamboo/overview ) to build / deploy an application.
It would be technically possible to do this with some tweaking, but the Terms of Service prohibit apps that upload other apps.
It sounds interesting to me, but ultimately I'm not sure of the practicality of it. You'd have to spend quite a bit of effort to modify the SDK to replace all file operations, and emulate the development filesystem on either the filestore or blobstore.
I say I don't think it's practical, because unless you're running strictly as backends (which ends up being expensive), none of the frontends really last long enough to emulate a debugger. It would be very difficult to develop software if you can't debug.
That and what Nick said.
Related
Such questions have been asked before - but all of the answers are outdated now.
I am looking forward to work on a Scala based webapp. I understand this question can be split into two, but I am posting them as one because they rely on same context, there being a dependency on the hosting platform and frameworks used.
I have read multiple (awesome) debates on Play! and Lift, but cannot find a good comparison between Play! 2.1 and Lift. How do I decide which one is better for my scenario (a social network website) ?
Similarly, this discussion has some very good arguments as to which platform to use for if I go with Lift, but it's from 2010 and seems outdated. The recommended provider (stax.net) is dead (or I guess it's merged with cloudbees.com). I am personally inclined towards GAE, as they are quick to start with, but unsure if the issues still prevail :
Support for actors (I am not sure if Akka helps us solve this problem)
Requests for a given session being served by different JVMs without notice to running app
Quoting David Pollak (lead author of Lift) :
GAE is slow and non-scalable, despite Google's claims (everyone I've
spoken with that have tried to scale GAE apps have failed and gone
elsewhere). GAE locks you into a tremendously suboptimal storage
mechanism. GAE is free, but so is Stax and there are many inexpensive
options including SliceHost. Next up, you've got Amazon EC2 and
RackSpace. So, I haven't found a good reason for anyone to use GAE.
And if there's no good reason to use GAE, devoting a pile of resources
to code around the GAE JVM incompatibilities (e.g., no new threads)
seems like a waste.
Another issue if I go with GAE is lack of Play! 2.1 support. I still don't see a module for that. Another issue is difficulty to migrate to other databases (although I hear migrating to MongoDB should be relatively easier) in the future. Worst case would be to move out of GAE and use AppScale.
Personally I use Lift, Cloudbees, and MongoLab as my first choice for most of my projects. I tried several cloud hosting services to no avail (Heroku and RedHat in particular. I don't think I tried GAE due to the post from David Pollak that you have already referenced). To use cloudbees, you just need an sbt plugin. Then it is as easy as running the cloudbees-deploy target. Within a minute, your code is up and running. I was floored by how easy it was. I went with Mongo primarily because of this excellent g8 template (note, there is now an SQL equivalent)
Another thing I really like about Cloudbees and MongoLab is they both have free services. It's great for me because I only work on these projects in my free time, so I don't want to spend any money while my ideas are half-baked.
As for Lift, I can't compare it much to Play. I downloaded/installed play and was immediately turned off by how MVC it is. I felt that the view-first approach, albeit foreign to me, seemed to be a much more intuitive and powerful way to build web applications. I love how Lift doesn't obscure from me the fact that I am indeed developing a web application. I often feel that MVC frameworks try to keep all of the HTML/CSS/JS etc at an arms-length.
The question is quite open so I will share my experience and opinion regarding Scala web app development as it might help you with your decision.
I built my first scala web application using Scalatra and Scalate using Jetty as the server. The app is hosted on an Amazon EC2 instance and I've had no problems with this... it's been running since the end of 2011 with only one small blip that took 10 mins to resolve. I found it a good experience for learning to use Scala in web applications.
http://www.scalatra.org/
Typesafe (http://typesafe.com) appear to have opted for the Play Framework and so for my next scala based web app I am likely to go for Play. A book I have been reading on the Play Framework is "Play for Scala". It has just been published this month (Oct 2013).
http://www.manning.com/hilton/
My impression is that Lift was the go-to framework in the past but that this has shifted to the Play Framework.
If I for some reason wanted to use my own private server to run my GAE app instead of deploying it to Google servers, could I simply use AppEngine SDK to do that? Are there any technical or legal limitations or problems that I should know about? I know that the SDK isn't designed to run heavy pages but for small websites it should work right?
The dev_appserver is not built to serve public-facing traffic. It's single-threaded, not built for performance, the backends are likewise limited, and it exposes administrative endpoints (such as /_ah/admin/) which users should not be able to access.
Alternatives exist for hosting your app yourself, such as TyphoonAE and AppScale.
Well, you could try. I'm not aware of any legal issues (with the caveat that I Am Not A Lawyer, and can't offer to interpret the license agreement for you), but I doubt you'd be happy with performance.
For one, the dev_appserver Datastore emulation (in both the Python and Java SDKs) doesn't scale all that well once you're past small amounts of data. It's not designed for performance; it's designed to accurately mimic the semantics of the real Datastore.
I have been doing high performance scientific computing in c++ most of my life. I am trying to learn to developing AJAXy web applications. As an exercise, I would like to build something that has a subset of functionality of facebook (profiles, posts with comment threads, friend lists) + the ability to search any post/comment.
I have no experience developing these kind of apps, except minor amount of toying with Google Appengine with GWT+Java and little bit of python. What tools/stack would you suggest using for it? I understand that this a very vague question, but I'd like to get a few opinions and your thought process about how would you go about using it.
How does the choice change, if you want a fast prototype as fast as possible, vs if you are trying to build something that can scale and last a few cycles of feature requests.
To be more specific, I'm lost in questions like, should I consider Drupal, should I consider Lucene for search, Would GWT get me what I want in the UI or would python+django be faster to develop. Probably I should not over think and pick something. But some perspective from others would be nice.
If you have started out with Python, that might be the easiest to get going with, especially since you have some experience with Google's App Engine already. However, if you have spent most of your time working with C++ ... did you know that C++ has at least two different full-stack web frameworks?
CppCMS
Wt (WebToolkit)
Remember, it's what you develop fastest in that makes the difference in the long run. What will slow you down most of all is dealing with what you dislike. So, if long compile times kill you, then try Python, Ruby, PHP, or some other dynamic language. If having code that is less than perfectly optimized (and slower that it could be) is what bothers you most, use C++, C#, or Java instead.
One disadvantage with google app engine is that there is no CMS like drupal or Joomla for google app engine so you're going to have to write your own if you want some of that functionality. The advantages of google app engine however outweigh the disadvantage since you have easier development, easier deployment, won't have to fiddle with phpmyadmin or other ugly sql interfaces, with app engine you also leverage google's huge infrastructure and since it's cloud computing you only pay for what you use. If you want something you as a developer will be most happy about - then I recommend you choose Google App Engine.
We are using GAE to host our web services, as far as I know GAE only support Java and python at the moment, however most of our engineers here are more comfortable with C/C++, so i was wondering if there is a way to integrate gsoap with GAE at all. Thanks for your help!
Though I am not an expert at Google App Engine, it is unlikely you'd be able to use native C++ code in the app engine. Based on experience with an app engine like Tomcat, the purpose of application engines is to make your application run on a shared service in its own little sandbox so that it can't affect the other shared services. With C++, you can get a pointer to the beginning of the process memory and start writing zeros if you so desired. This doesn't turn out to work too well in a shared computing environment.
The app engine pages indicate Java and Python runtime environments are available. I've been using C++ for many years and am a big fan of gSoap, but I think these are tools best used in limited cases these days. Web services for Java aren't that much different from gSoap in terms of ramp-up time anyway.
I've used Axis2 for Java web services and it isn't that difficult to use. However, I think it suffers from being overly complex and under documented. I have used WSO2 under PHP and was impressed with how easy it was to use. WSO2 is built on top of Axis and has a Java port too (though I have not used it). If your engineers want to dig in, WSO2 is probably going to be the easiest route.
Motivating them might be hard, but my take is that if they are real software engineers then they won't have a problem adapting.
This might be helpful too: http://code.google.com/appengine/docs/java/overview.html
The short answer is No, Google-App engine is very limited with what you can do (you can't even dynamically create new files).
I am trying to scrape some website and republish the data as a RSS feed. How hard is this to setup with Google App Engine? Disadvantages and Advantages using GAE. Any recommendations and guidelines greatly appreciated!
Google AppEngine offers much more functionality (and complexity) than you will need if truly all you will want to do is republish some structured data as RSS.
Personally, I would use something like Yahoo pipes for a task like this.
That being said... if you want/need to get your feet wet with GAE, go for it!
Working with Google App Engine is pretty straight forward. I would recommend going through the Getting Started guide. It's short and simple and touches on essential GAE topics. There are more pros and cons than I will list here.
Pros:
In general, App Engine is designed for high traffic web applications that need to scale. Furthermore, it is designed from a programmer's perspective. Much of the scalability issues (database optimization, server administration, etc) are dealt with by Google. Having said that, I find it to be a nice platform. It is still being actively developed by Google engineers, and scheduling of tasks (a feature that has been long requested) is in the current road map.
Cons:
Perhaps the biggest downside right now is again the lack of official scheduling support and the quota limits currently set for free accounts. However you can't complain much if its free. Currently it only supports Python as a programming interface (although a new language [Java I predict] is coming soon). Furthermore, Python 2.6 (and 3.0 for that matter) are not yet supported. In addition, Django 1.0 is not officially supported in App Engine (although you can package Django 1.0 with your application).
Harder than it would be in most other technologies.
GAE can sort of do scheduled batch stuff like this now, but it's really not intended for that type of thing. Pick pretty much any other language and platform for this particular task, and you'll make your life a lot easier.
I think BeautifulSoup could run on GAE, so all your scraping needs are handled :D
Also, GAE has a geturl thingy. The only problem I think you might have is not having enough time to get the data (30 secs limitation).
I am working on a same project and I've decided that it's easier to prepare the data on another server and push them to GAE.
You might also want to look into Yahoo! Query Language (YQL)