Tag Archives: Java SDK

12 B2 Power Tips for Experts and Developers

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/advanced-cloud-storage-tips/

B2 Tips for Pros
If you’ve been using B2 Cloud Storage for a while, you probably think you know all that you can do with it. But do you?

We’ve put together a list of blazing power tips for experts and developers that will take you to the next level. Take a look below.

If you’re new to B2, we have a list of power tips for you, too.
Visit 12 Power Tips for New B2 Users.
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1    Manage File Versions

Use Lifecycle Rules on a Bucket to set how many days to keep files that are no longer the current version. This is a great way to manage the amount of space your B2 account is using.

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2    Easily Stay on Top of Your B2 Account Limits

Set usage caps and get text/email alerts for your B2 account when you approach limits that you define.

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3    Bring on Your Big Files

You can upload files as large as 10TB to B2.

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4    You Can Use FedEx to Get Your Data into B2

If you have over 20TB of data, you can use Backblaze’s Fireball hard disk array to load large volumes of data directly into your B2 account. We ship a Fireball to you and you ship it back.

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5    You Have Command-Line Control of All B2 Functions

You have complete control over B2 using our command line tool that is available for Macintosh, Windows, and Linux.

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6    You Can Use Your Own Domain Name To Front a Public B2 Bucket

You can create a vanity URL for your B2 account.

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7    See What’s Happening in Your Account with Graphical Reports

You can view graphical reports summarizing your B2 usage — transactions, downloads, averages, data stored — in your B2 account dashboard.

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8    Create a B2 SDK

You can build your own B2 SDK for JVM-based or JVM-compatible languages using our B2 Java SDK on Github.

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9    B2’s API is Easy to Use

B2’s API is similar to, but simpler than Amazon’s S3 API, making it super easy for developers to integrate with B2 Cloud Storage.

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10    View Code Examples To Get Your B2 Project Started

The B2 API is well documented and has code examples for cURL, Java, Python, Swift, Ruby, C#, and PHP. For example, here’s how to create a B2 Bucket.

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11    Developers can set the B2 part size as low as 5 MB

When working with large files, the minimum file part size can be set as low as 5MB or as high as 5GB. This gives developers the ability to maximize the throughput of B2 data uploads and downloads. See Large Files and Downloading for more developer tips.

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12    Your App or Device Can Work with B2, as well

Your B2 integration can be listed on Backblaze’s website. Visit Submit an Integration to get started.

Want to Learn More About B2?

You can find more information on B2 on our website and in our help pages.

The post 12 B2 Power Tips for Experts and Developers appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

B2 Cloud Storage Roundup

Post Syndicated from Andy Klein original https://www.backblaze.com/blog/b2-cloud-storage-roundup/

B2 Integrations
Over the past several months, B2 Cloud Storage has continued to grow like we planted magic beans. During that time we have added a B2 Java SDK, and certified integrations with GoodSync, Arq, Panic, UpdraftPlus, Morro Data, QNAP, Archiware, Restic, and more. In addition, B2 customers like Panna Cooking, Sermon Audio, and Fellowship Church are happy they chose B2 as their cloud storage provider. If any of that sounds interesting, read on.

The B2 Java SDK

While the Backblaze B2 API is well documented and straight-forward to implement, we were asked by a few of our Integration Partners if we had an SDK they could use. So we developed one as an open-course project on GitHub, where we hope interested parties will not only use our Java SDK, but make it better for everyone else.

There are different reasons one might use the Java SDK, but a couple of areas where the SDK can simplify the coding process are:

Expiring Authorization — B2 requires an application key for a given account be reissued once a day when using the API. If the application key expires while you are in the middle of transferring files or some other B2 activity (bucket list, etc.), the SDK can be used to detect and then update the application key on the fly. Your B2 related activities will continue without incident and without having to capture and code your own exception case.

Error Handling — There are different types of error codes B2 will return, from expired application keys to detecting malformed requests to command time-outs. The SDK can dramatically simplify the coding needed to capture and account for the various things that can happen.

While Backblaze has created the Java SDK, developers in the GitHub community have also created other SDKs for B2, for example, for PHP (https://github.com/cwhite92/b2-sdk-php,) and Go (https://github.com/kurin/blazer.) Let us know in the comments about other SDKs you’d like to see or perhaps start your own GitHub project. We will publish any updates in our next B2 roundup.

What You Can Do with Affordable and Available Cloud Storage

You’re probably aware that B2 is up to 75% less expensive than other similar cloud storage services like Amazon S3 and Microsoft Azure. Businesses and organizations are finding that projects that previously weren’t economically feasible with other Cloud Storage services are now not only possible, but a reality with B2. Here are a few recent examples:

SermonAudio logoSermonAudio wanted their media files to be readily available, but didn’t want to build and manage their own internal storage farm. Until B2, cloud storage was just too expensive to use. Now they use B2 to store their audio and video files, and also as the primary source of downloads and streaming requests from their subscribers.
Fellowship Church logoFellowship Church wanted to escape from the ever increasing amount of time they were spending saving their data to their LTO-based system. Using B2 saved countless hours of personnel time versus LTO, fit easily into their video processing workflow, and provided instant access at any time to their media library.
Panna logoPanna Cooking replaced their closet full of archive hard drives with a cost-efficient hybrid-storage solution combining 45Drives and Backblaze B2 Cloud Storage. Archived media files that used to take hours to locate are now readily available regardless of whether they reside in local storage or in the B2 Cloud.

B2 Integrations

Leading companies in backup, archive, and sync continue to add B2 Cloud Storage as a storage destination for their customers. These companies realize that by offering B2 as an option, they can dramatically lower the total cost of ownership for their customers — and that’s always a good thing.

If your favorite application is not integrated to B2, you can do something about it. One integration partner told us they received over 200 customer requests for a B2 integration. The partner got the message and the integration is currently in beta test.

Below are some of the partner integrations completed in the past few months. You can check the B2 Partner Integrations page for a complete list.

Archiware — Both P5 Archive and P5 Backup can now store data in the B2 Cloud making your offsite media files readily available while keeping your off-site storage costs predictable and affordable.

Arq — Combine Arq and B2 for amazingly affordable backup of external drives, network drives, NAS devices, Windows PCs, Windows Servers, and Macs to the cloud.

GoodSync — Automatically synchronize and back up all your photos, music, email, and other important files between all your desktops, laptops, servers, external drives, and sync, or back up to B2 Cloud Storage for off-site storage.

QNAP — QNAP Hybrid Backup Sync consolidates backup, restoration, and synchronization functions into a single QTS application to easily transfer your data to local, remote, and cloud storage.

Morro Data — Their CloudNAS solution stores files in the cloud, caches them locally as needed, and syncs files globally among other CloudNAS systems in an organization.

Restic – Restic is a fast, secure, multi-platform command line backup program. Files are uploaded to a B2 bucket as de-duplicated, encrypted chunks. Each backup is a snapshot of only the data that has changed, making restores of a specific date or time easy.

Transmit 5 by Panic — Transmit 5, the gold standard for macOS file transfer apps, now supports B2. Upload, download, and manage files on tons of servers with an easy, familiar, and powerful UI.

UpdraftPlus — WordPress developers and admins can now use the UpdraftPlus Premium WordPress plugin to affordably back up their data to the B2 Cloud.

Getting Started with B2 Cloud Storage

If you’re using B2 today, thank you. If you’d like to try B2, but don’t know where to start, here’s a guide to getting started with the B2 Web Interface — no programming or scripting is required. You get 10 gigabytes of free storage and 1 gigabyte a day in free downloads. Give it a try.

The post B2 Cloud Storage Roundup appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

How to Use Batch References in Amazon Cloud Directory to Refer to New Objects in a Batch Request

Post Syndicated from Vineeth Harikumar original https://aws.amazon.com/blogs/security/how-to-use-batch-references-in-amazon-cloud-directory-to-refer-to-new-objects-in-a-batch-request/

In Amazon Cloud Directory, it’s often necessary to add new objects or add relationships between new objects and existing objects to reflect changes in a real-world hierarchy. With Cloud Directory, you can make these changes efficiently by using batch references within batch operations.

Let’s say I want to take an existing child object in a hierarchy, detach it from its parent, and reattach it to another part of the hierarchy. A simple way to do this would be to make a call to get the object’s unique identifier, another call to detach the object from its parent using the unique identifier, and a third call to attach it to a new parent. However, if I use batch references within a batch write operation, I can perform all three of these actions in the same request, greatly simplifying my code and reducing the round trips required to make such changes.

In this post, I demonstrate how to use batch references in a single write request to simplify adding and restructuring a Cloud Directory hierarchy. I have used the AWS SDK for Java for all the sample code in this post, but you can use other language SDKs or the AWS CLI in a similar way.

Using batch references

In my previous post, I demonstrated how to add AnyCompany’s North American warehouses to a global network of warehouses. As time passes and demand grows, AnyCompany launches multiple warehouses in North American cities to fulfill customer orders with continued efficiency. This requires the company to restructure the network to group warehouses in the same region so that the company can apply similar standards to them, such as delivery times, delivery areas, and types of products sold.

For instance, in the NorthAmerica object (see the following diagram), AnyCompany has launched two new warehouses in the Phoenix (PHX) area: PHX_2 and PHX_3. AnyCompany wants to add these new warehouses to the network and regroup them with existing warehouse PHX_1 under the new node, PHX.

The state of the hierarchy before this regrouping is shown in the following diagram, where I added the NorthAmerica warehouses (also represented as NA in the diagram) to the larger network of AnyCompany’s warehouses.

Diagram showing the state of the hierarchy before this post's regrouping

Adding and grouping new warehouses in the NorthAmerica network

I want to add and group the new warehouses with a single request, and using batch references in a batch write lets me do that. A batch reference is just another way of using object references that you are allowed to define arbitrarily. This allows you to chain operations, which means using the return value from one operation in a subsequent operation within the same batch write request

Let’s say I have a batch write request with two batch operations: operation A and operation B. Both batch operations operate on the same object X. In operation A, I use the object X found at /NorthAmerica/Phoenix, and I assign it to a batch reference that I call referencePhoenix. In operation B, I want to modify the same object X, so I use referencePhoenix as the object reference that points to the same unique object X used in operation A. I also will use the same helper method implementation from my previous post for getBatchCreateOperation. To learn more about batch references, see the ObjectReference documentation.

To add and group the new warehouses, I will take advantage of batch references to sequentially:

  1. Detach PHX_1 from the NA node and maintain a reference to PHX_1.
  2. Create a new child node, PHX, and attach it to the NA node.
  3. Create PHX_2 and PHX_3 nodes for the new warehouses.
  4. Link all three nodes—PHX_1 (using the batch reference), PHX_2, and PHX_3—to the PHX node.

The following code example achieves these changes in a single batch by using references. First, the code sets up a createObjectPHX operation to create the PHX parent object and attach it to the parent NorthAmerica object. It then sets up createObjectPHX_2 and createObjectPHX_3 and attaches these new objects to the new PHX object. The code then sets up a detachObject to detach the current PHX_1 object from its parent and assign it to a batch reference. The last operation uses that same batch reference to attach the PHX_1 object to the newly created PHX object. The code example orders these steps sequentially in a batch write operation.

   BatchWriteOperation createObjectPHX = getBatchCreateOperation(
   BatchWriteOperation createObjectPHX_2 = getBatchCreateOperation(
   BatchWriteOperation createObjectPHX_3 = getBatchCreateOperation(

   BatchDetachObject detachObject = new BatchDetachObject()
        .withParentReference(new ObjectReference()

   BatchAttachObject attachObject = new BatchAttachObject()
        .withChildReference(new ObjectReference().withSelector("#referenceToPHX_1"))
        .withParentReference(new ObjectReference()

   BatchWriteOperation detachOperation = new BatchWriteOperation()
   BatchWriteOperation attachOperation = new BatchWriteOperation()

   BatchWriteRequest request = new BatchWriteRequest();


In the preceding code example, I use the batch reference, referenceToPHX_1, in the same batch write operation because I do not have to know the object identifier of that object. If I couldn’t use such a batch reference, I would have to use separate requests to get the PHX_1 identifier, detach it from the NA node, and then attach it to the new PHX node.

I now have the network configuration I want, as shown in the following diagram. I have used a combination of batch operations with batch references to bring new warehouses into the network and regroup them within the same local group of warehouses.

Diagram showing the desired network configuration


In this post, I have shown how you can use batch references in a single batch write request to simplify adding and restructuring your existing hierarchies in Cloud Directory. You can use batch references in scenarios where you want to get an object identifier, but don’t want the overhead of using a read operation before a write operation. Instead, you can use a batch reference to refer to an object as part of the intermediate batch operation. To learn more about batch operations, see Batches, BatchWrite, and BatchRead.

If you have comments about this post, submit them in the “Comments” section below. If you have implementation questions, start a new thread on the Directory Service forum.

– Vineeth

Write and Read Multiple Objects in Amazon Cloud Directory by Using Batch Operations

Post Syndicated from Vineeth Harikumar original https://aws.amazon.com/blogs/security/write-and-read-multiple-objects-in-amazon-cloud-directory-by-using-batch-operations/

Amazon Cloud Directory is a hierarchical data store that enables you to build flexible, cloud-native directories for organizing hierarchies of data along multiple dimensions. For example, you can create an organizational structure that you can navigate through multiple hierarchies for reporting structure, location, and cost center.

In this blog post, I demonstrate how you can use Cloud Directory APIs to write and read multiple objects by using batch operations. With batch write operations, you can execute a sequence of operations atomically—meaning that all of the write operations must occur, or none of them do. You also can make your application efficient by reducing the number of required round trips to read and write objects to your directory. I have used the AWS SDK for Java for all the sample code in this blog post, but you can use other language SDKs or the AWS CLI in a similar way.

Using batch write operations

To demonstrate batch write operations, let’s say that AnyCompany’s warehouses are organized to determine the fastest methods to ship orders to its customers. In North America, AnyCompany plans to open new warehouses regularly so that the company can keep up with customer demand while continuing to meet the delivery times to which they are committed.

The following diagram shows part of AnyCompany’s global network, including Asian and European warehouse networks.

Let’s take a look at how I can use batch write operations to add NorthAmerica to AnyCompany’s global network of warehouses, with the first three warehouses in New York City (NYC), Las Vegas (LAS), and Phoenix (PHX).

Adding NorthAmerica to the global network

To add NorthAmerica to the global network, I can use a batch write operation to create and link all the objects in the existing network.

First, I set up a helper method, which performs repetitive tasks, for the getBatchCreateOperation object. The following lines of code help me create an NA object for NorthAmerica and then attach the three city-related nodes: NYC, LAS, and PHX. Because AnyCompany is planning to grow its network, I add a suffix of _1 to each city code (such as PHX_1), which will be helpful hierarchically when the company adds more warehouses within a city.

    private BatchWriteOperation getBatchCreateOperation(
            String warehouseName,
            String directorySchemaARN,
            String parentReference,
            String linkName) {

        SchemaFacet warehouse_facet = new SchemaFacet()

        AttributeKeyAndValue kv = new AttributeKeyAndValue()
            .withKey(new AttributeKey()
            .withValue(new TypedAttributeValue()

        List<SchemaFacet> facets = Lists.newArrayList(warehouse_facet);
        List<AttributeKeyAndValue> kvs = Lists.newArrayList(kv);

        BatchCreateObject createObject = new BatchCreateObject();

        createObject.withParentReference(new ObjectReference()


        return new BatchWriteOperation().withCreateObject

The parameters of this helper method include:

  • warehouseName – The name of the warehouse to create in the getBatchCreateOperation object.
  • directorySchemaARN – The Amazon Resource Name (ARN) of the schema applied to the directory.
  • parentReference – The object reference of the parent object.
  • linkName – The unique child path from the parent reference where the object should be attached.

I then use this helper method to set up multiple create operations for NorthAmerica, NewYork, Phoenix, and LasVegas. For the sake of simplicity, I use airport codes to stand for the cities (for example, NYC stands for NewYork).

   BatchWriteOperation createObjectNA = getBatchCreateOperation(
   BatchWriteOperation createObjectNYC = getBatchCreateOperation(
   BatchWriteOperation createObjectPHX = getBatchCreateOperation(
   BatchWriteOperation createObjectLAS = getBatchCreateOperation(

   BatchWriteRequest request = new BatchWriteRequest();


Running the preceding code results in a hierarchy for the network with NA added to the network, as shown in the following diagram.

Using batch read operations

Now, let’s say that after I add NorthAmerica to AnyCompany’s global network, an analyst wants to see the updated view of the NorthAmerica warehouse network as well as some information about the newly introduced warehouse configurations for the Phoenix warehouses. To do this, I can use batch read operations to get the network of warehouses for NorthAmerica as well as specifically request the attributes and configurations of the Phoenix warehouses.

To list the children of the NorthAmerica warehouses, I use the BatchListObjectChildren API to get all the children at the path, /NorthAmerica. Next, I want to view the attributes of the Phoenix object, so I use the BatchListObjectAttributes API to read all the attributes of the object at /NorthAmerica/Phoenix, as shown in the following code example.

    BatchListObjectChildren listObjectChildrenRequest = new BatchListObjectChildren()
        .withObjectReference(new ObjectReference().withSelector("/NorthAmerica"));
    BatchListObjectAttributes listObjectAttributesRequest = new BatchListObjectAttributes()
        .withObjectReference(new ObjectReference()
    BatchReadRequest batchRead = new BatchReadRequest()
        .withOperations(Lists.newArrayList(listObjectChildrenRequest, listObjectAttributesRequest));

    BatchReadResult result = client.batchRead(batchRead);

Exception handling

Batch operations in Cloud Directory might sometimes fail, and it is important to know how to handle such failures, which differ for write operations and read operations.

Batch write operation failures

If a batch write operation fails, Cloud Directory fails the entire batch operation and returns an exception. The exception contains the index of the operation that failed along with the exception type and message. If you see RetryableConflictException, you can try again with exponential backoff. A simple way to do this is to double the amount of time you wait each time you get an exception or failure. For example, if your first batch write operation fails, wait 100 milliseconds and try the request again. If the second request fails, wait 200 milliseconds and try again. If the third request fails, wait 400 milliseconds and try again.

Batch read operation failures

If a batch read operation fails, the response contains either a successful response or an exception response. Individual batch read operation failures do not cause the entire batch read operation to fail—Cloud Directory returns individual success or failure responses for each operation.

Limits of batch operations

Batch operations are still constrained by the same Cloud Directory limits as other Cloud Directory APIs. A single batch operation does not limit the number of operations, but the total number of nodes or objects being written or edited in a single batch operation have enforced limits. For example, a total of 20 objects can be written in a single batch operation request to Cloud Directory, regardless of how many individual operations there are within that batch. Similarly, a total of 200 objects can be read in a single batch operation request to Cloud Directory. For more information, see limits on batch operations.


In this post, I have demonstrated how you can use batch operations to operate on multiple objects and simplify making complicated changes across hierarchies. In my next post, I will demonstrate how to use batch references within batch write operations. To learn more about batch operations, see Batches, BatchWrite, and BatchRead.

If you have comments about this post, submit them in the “Comments” section below. If you have implementation questions, start a new thread on the Directory Service forum.

– Vineeth