I would like my server that runs on Google App Engine to host large files such as audio scripts and images, is it possible to store them as a column in a database? If not, what mechanisms may I use?
You have two options:
Blobstore (currently available in Java, Python and Go).
Google Cloud Storage (currently available in Java, Python and PHP).
Blobstore and GCS are most likely what your are looking for.
Both services are not covered by the GAE SLAs however. If you need that kind of reliability promise you're stuck with the GAE datastore.
You can put your files in a BLOB property of a datastore entity and serve it from there. Datastore entities have a size limit of 1MB however.
To circumvent that, you must split and re-assemble your files using multiple entities. There again is a size limit to any GAE response which is 32MB.
Related
What is the difference between backing up my entities to the Google Blob store versus to Google Cloud Storage? There does not seem to have much explanation on the differences.
Honestly, now that they both have the same basic quota and paid limitations, I don't think there is much of a difference between both. It's going to be mostly how you access/do calls on both.
For the blobstore, there is a nifty API (in Python or in Java)
For Google Cloud Storage, you need to get the client library and add it to your project before using it (again, in Python or in Java)
At this point, it mostly has to do with my own experience, but if all you do is store files and retrieve them, I prefer the blobstore API to the GCS client library (easier to use, I find).
In terms of cost.... the GCS will be cheaper (they both provide the same free size, and the same price per storage, but blobstore charges more for calls).
I do believe that in the backend they are VERY similar, so the difference is mostly in how you pay for them/what you need to setup to
I need to store images and I have 2 options:
store the image into GAE datastore.
store the image somewhere (maybe also on Dropbox or another website) and store its link into GAE datastore.
What's the best practice when we need to store an image into DB, in the hypotesis that each image is bijectivelly linked to a specific element of the datastore?
I think it depends heavily on the use case.
I have a small company website running on appengine and the content images are all stored in the datastore and for that application it works well (they are all relatively small images).
If you have a high traffic site you may find storing them in GCS, or some other mechanism that supports a more cost effective CDN will be more appropriate.
If the images are large (more than 1MB) then the datastore isn't a practical solution.
There will be no hard and fast rule. Understand your use cases, your cost structure, how complex the solution will be to manage, and then choose the most appropriate solution.
Neither of the above. Google's cloud platform includes a service specifically for storing files, Google Cloud Storage, which is well integrated into GAE. You should use that.
I am writing a web application that requires a database which will have entities like user, friends etc. Since Cloud SQL service is not free so i am looking for alternatives. Amazon RDS is one option, since they have a free tier which would suit my needs in the short term but before I get into it I would like to know more about blobstores.
Is it ideal to use blobstore to store such kind of information?
There are questions like:
how will the read/write latency be compared to a traditional db ?
if i start with blobstore and later i want to move to relational db, what are the problems that i could face ?
The most important of all is, if it is ideal to use blobstore in my scenario.
After looking at the documentation on google dev site I have found that blobstores are used to store large/medium files like images and videos.
You can't and shouldn't try to use the blobstore for structured data. That's what the datastore is for. Blobstore is for unstructured data such as files.
If I were to make a project with the Google App Engine (using Python), and this project contained small user-generated images (which, once uploaded, will be accessed a lot, but won't change or altered dynamically anymore), would the Google App Engine BlobStore make sense to use (in terms of costs, speed etc.)? Or would GAE or the client connecting to Amazon S3 and storing images there make more sense, as these files will end up being static?
For what it's worth, the generated image files are all considered to be public, not user-private, and it would be perfectly fine for them to be on another subdomain. All files will be fixed-palette 16 colors PNGs of exactly 19x19 pixels. Their URL/ID would be referenced in the GAE datastore, with a couple of more attributes (like creatorId), for handling/ showing them in the web app.
Thanks!
If you are concerned about speed and cost, by far the best way is to store them in the blobstore and use get_serving_url() (link). These images are served by google's high performance image servers, and will never cost you instance hours, just bandwidth, and you don't have to worry about memcache.
I asked a similar question a few days ago.
Im sticking with storing the images in the DataStore as BLOBS (not in the BlobStore) and ensuring i set a Cache Control header to ensure they arent requested too many times.
For such small images, you can simply use the Datastore. Even with the 1Gb of space it gives you in the free quotas you should be able to store a few 19x19 pixels images easily. Using BlobStore is slightly more complicated as the API's are more complex and the actual sotorage procedure involves more steps than just storing binary data in the DataStore. I do recommend however that you implement memCache for the retrieval of these images, since you say that will not be modified afterwards. You don't want to query the same 19*19*4 bytes out of the database for each image over and over.
I'm reading up on Google App engine and I'm thinking of using it as a CDN for a project I'm working on. As far as I can tell, there's two ways to store data. I could use a datastore or I could put files in a directory.
I was brought up believing it's a bad idea to store large binary data in a database, but according to Google, the datastore isn't an RMDB, it just acts like one.
So my gut is telling me to upload files to a directory. However, I thought I'd best canvas an opinion on here before making my mind up.
Has anyone used GAE for stuff like this? And if so, what method did you choose for storing files, and why?
You cannot write to the file system in App Engine. You need to use the Datastore to store any data.
Note that if your "large binary files" are actually large, you're going to run in to the 1MB limit on all API calls. An API for storing larger blobs is on the roadmap, but there's no way of knowing when it will be released. At present, you need to split blobs larger than 1MB into multiple datastore entities.
The blobstore API lets you store files upto 50 mb ,though its an experimental api and requires billing be enabled.Also its its different from bigtable.
http://code.google.com/appengine/docs/java/blobstore/
Nowadays Google Cloud Storage is the way to go for large files.