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Can someone help me understand how block reads happen on Datanode in HDFS over http (basically in case of webhdfs)?

Can someone help me understand how block reads happen on Datanode in HDFS over http (basically in case of webhdfs)?

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I am trying to understand complete HDFS file read workflow over http in case of webhdfs.

When HTTP client request to read a file, the request goes to Namenode. Namenode responds back to client with the datanode address(block location) with block access token for client's authentication. This reponse of Namenode to client is in the form of redirect and with this redirect client send request to datanodes to read required blocks. Now my question is, how data streams are happening from datanode to client?