Pull from Azure Blob Storage¶

Azure Blob Storage is an object storage solution for the cloud that is optimized for storing massive amounts of unstructured data.

Important

Use this data source to pull data to Amperity from Azure Data Lake Storage Gen1 or Azure Data Lake Storage Gen2.

This topic describes the steps that are required to pull files in any supported format to Amperity from Azure Blob Storage:

Get details
Add courier
Get sample files
Add feeds
Add load operations
Run courier
Add to courier group

Get details¶

Amperity can be configured to pull data from Azure Blob Storage. This may be done using Azure Data Share or by using Azure Blob Storage credentials.

Use credentials¶

A source that uses credentials to send data to Amperity from Azure Blob Storage requires the following information be sent to Amperity via SnapPass:

The URL for the Azure authentication endpoint. This is typically in the format of https://login.microsoftonline.com/<directory_id>/oauth2/token.
The information needed for the selected credentials method: shared access credentials, a storage URI, or a connection string.
The name of the container, the blob prefix, and credential details. (These vary depending on the chosen credential method.)
A list of files (by filename and file type) in Azure Blob Storage to be sent to Amperity.
A sample for each file to simplify feed creation.

Add courier¶

A courier brings data from external system to Amperity. A courier relies on a feed to know which fileset to bring to Amperity for processing.

Tip

You can run a courier without load operations. Use this approach to get files to upload during feed creation, as a feed requires knowing the schema of a file before you can apply semantic tagging and other feed configuration settings.

for Azure credentials¶

Credentials options to access Azure Blob Storage include shared access signatures, connection strings, and storage URLs.

To add a courier

From the Sources tab, click Add Courier. The Add Source page opens.
Find, and then click the icon for Azure Blob Storage. The Add Courier page opens.

This automatically selects azure-blob-connection-string as the Credential Type. You may switch to using azure-blob-storage-uri or azure-blob-shared-access-signature.
From the Credential drop-down, select Create a new credential. This opens the Create New Credential dialog box.
Enter a name for the credential, any credential type-specific settings, and then click Save.

For the “azure-blob-connection-string” credential type, enter the name of the credential and the connection string.

For the “azure-blob-storage-uri” credential type, enter the name of the credential and the URI for the Azure Data Lake Storage instance.

For the “azure-blob-shared-access-signature” credential type, enter the name of the credential, the account name, and the shared access signature.
Under Azure Blob Storage Settings, add the name of the container and the blob prefix.

Under Azure Blob Storage Settings configure the list of files to pull to Amperity. Configure the Entities List for each file to be loaded to Amperity. For example, two files: “CustomerRecords.csv” and “TransactionRecords.csv”.

[
  {
    "object/type": "file",
    "object/file-pattern": "'/path/to/CustomerRecords.csv'",
    "object/land-as": {
      "file/header-rows": 1,
      "file/tag": "customer-records-2019",
      "file/content-type": "text/csv"
    }
  },
  {
    "object/type": "file",
    "object/file-pattern": "'/path/to/TransactionRecords.csv'",
    "object/land-as": {
      "file/header-rows": 1,
      "file/tag": "transaction-records-2019",
      "file/content-type": "text/csv"
    }
  }
]

Under Azure Blob Storage Settings set the load operations to a string that is obviously incorrect, such as df-xxxxxx. (You may also set the load operation to empty: {}.)

Tip

If you use an obviously incorrect string, the load operation settings will be saved in the courier configuration. After the schema for the feed is defined and the feed is activated, you can edit the courier and replace the feed ID with the correct identifier.

Caution

If load operations are not set to {} the validation test for the courier configuration settings will fail.
Click Save.

Get sample files¶

Every Azure Blob Storage file that is pulled to Amperity must be configured as a feed. Before you can configure each feed you need to know the schema of that file. Run the courier without load operations to bring sample files from Azure Blob Storage to Amperity, and then use each of those files to configure a feed.

To get sample files

From the Sources tab, open the menu for a courier configured for Azure Blob Storage with empty load operations, and then select Run. The Run Courier dialog box opens.
Select Load data from a specific day, and then select today’s date.
Click Run.

Important

The courier run will fail, but this process will successfully return a list of files from Azure Blob Storage.

These files will be available for selection as an existing source from the Add Feed dialog box.

Wait for the notification for this courier run to return an error similar to:

Error running load-operations task
Cannot find required feeds: "df-xxxxxx"

Add feeds¶

A feed defines how data should be loaded into a domain table, including specifying which columns are required and which columns should be associated with a semantic tag that indicates that column contains customer profile (PII) and transactions data.

Note

A feed must be added for each file that is pulled from Azure Blob Storage, including all files that contain customer records and interaction records, along with any other files that will be used to support downstream workflows.

To add a feed

From the Sources tab, click Add Feed. This opens the Add Feed dialog box.
Under Data Source, select Create new source, and then enter “Azure Blob Storage”.
Enter the name of the feed in Feed Name. For example: “CustomerRecords”.

Tip

The name of the domain table will be “<data-source-name>:<feed-name>”. For example: “Azure Blob Storage:CustomerRecords”.
Under Sample File, select Select existing file, and then choose from the list of files. For example: “filename_YYYY-MM-DD.csv”.

Tip

The list of files that is available from this drop-down menu is sorted from newest to oldest.
Select Load sample file on feed activation.
Click Continue. This opens the Feed Editor page.
Select the primary key.
Apply semantic tags to customer records and interaction records, as appropriate.
Under Last updated field, specify which field best describes when records in the table were last updated.

Tip

Choose Generate an “updated” field to have Amperity generate this field. This is the recommended option unless there is a field already in the table that reliably provides this data.
For feeds with customer records (PII data), select Make available to Stitch.
Click Activate. Wait for the feed to finish loading data to the domain table, and then review the sample data for that domain table from the Data Explorer.

Add load operations¶

After the feeds are activated and domain tables are available, add the load operations to the courier used for Azure Blob Storage.

Example load operations

Load operations must specify each file that will be pulled to Amperity from Azure Blob Storage.

For example:

{
  "CUSTOMER-RECORDS-FEED-ID": [
    {
      "type": "truncate"
    },
    {
      "type": "load",
      "file": "customer-records"
    }
  ],
  "TRANSACTION-RECORDS-FEED-ID": [
    {
      "type": "load",
      "file": "transaction-records"
    }
  ]
}

To add load operations

From the Sources tab, open the menu for the courier that was configured for Azure Blob Storage, and then select Edit. The Edit Courier dialog box opens.
Edit the load operations for each of the feeds that were configured for Azure Blob Storage so they have the correct feed ID.
Click Save.

Run courier manually¶

Run the courier again. This time, because the load operations are present and the feeds are configured, the courier will pull data from Azure Blob Storage.

To run the courier manually

From the Sources tab, open the menu for the courier with updated load operations that is configured for Azure Blob Storage, and then select Run. The Run Courier dialog box opens.
Select the load option, either for a specific time period or all available data. Actual data will be loaded to a domain table because the feed is configured.
Click Run.

This time the notification will return a message similar to:
```
Completed in 5 minutes 12 seconds
```

Add to courier group¶

A courier group is a list of one (or more) couriers that are run as a group, either ad hoc or as part of an automated schedule. A courier group can be configured to act as a constraint on downstream workflows.

To add the courier to a courier group

From the Sources tab, click Add Courier Group. This opens the Create Courier Group dialog box.
Enter the name of the courier. For example: “Azure Blob Storage”.
Add a cron string to the Schedule field to define a schedule for the orchestration group.

A schedule defines the frequency at which a courier group runs. All couriers in the same courier group run as a unit and all tasks must complete before a downstream process can be started. The schedule is defined using cron.

Cron syntax specifies the fixed time, date, or interval at which cron will run. Each line represents a job, and is defined like this:
```
┌───────── minute (0 - 59)
│ ┌─────────── hour (0 - 23)
│ │ ┌───────────── day of the month (1 - 31)
│ │ │ ┌────────────── month (1 - 12)
│ │ │ │ ┌─────────────── day of the week (0 - 6) (Sunday to Saturday)
│ │ │ │ │
│ │ │ │ │
│ │ │ │ │
* * * * * command to execute
```
For example, 30 8 * * * represents “run at 8:30 AM every day” and 30 8 * * 0 represents “run at 8:30 AM every Sunday”. Amperity validates your cron syntax and shows you the results. You may also use crontab guru to validate cron syntax.
Set Status to Enabled.
Specify a time zone.

A courier group schedule is associated with a time zone. The time zone determines the point at which a courier group’s scheduled start time begins. A time zone should be aligned with the time zone of system from which the data is being pulled.

Note

The time zone that is chosen for an courier group schedule should consider every downstream business processes that requires the data and also the time zone(s) in which the consumers of that data will operate.
Set SLA? to False. (You can change this later after you have verified the end-to-end workflows.)
Add at least one courier to the courier group. Select the name of the courier from the Courier drop-down. Click + Add Courier to add more couriers.
Click Add a courier group constraint, and then select a courier group from the drop-down list.

A wait time is a constraint placed on a courier group that defines an extended time window for data to be made available at the source location.

A courier group typically runs on an automated schedule that expects customer data to be available at the source location within a defined time window. However, in some cases, the customer data may be delayed and isn’t made available within that time window.
For each courier group constraint, apply any offsets.

An offset is a constraint placed on a courier group that defines a range of time that is older than the scheduled time, within which a courier group will accept customer data as valid for the current job. Offset times are in UTC.

A courier group offset is typically set to be 24 hours. For example, it’s possible for customer data to be generated with a correct file name and datestamp appended to it, but for that datestamp to represent the previous day because of the customer’s own workflow. An offset ensures that the data at the source location is recognized by the courier as the correct data source.

Warning

An offset affects couriers in a courier group whether or not they run on a schedule.
Click Save.