Use of Batch adds duplicate, redundant gcloud-python/x.xx.x to User-Agent header in an unbounded fashion #565

from google.api_core import exceptions as g_exc
from google.cloud.storage.blob import Blob
from google.cloud.storage.client import Client

project = '<GCP PROJCT NAME>'
bucket_name = '<GCS BUCKET NAME>'

# Client.__init__ initializes self._connection which initiallizes a Connection object as defined in
# google.cloud.storage._http.py which automatically appends a 'gcloud-python/x.xx.x' spec to the
# the user_agent property
c = Client(project=project)
print(c._connection._client_info.user_agent)

bucket = c.get_bucket(bucket_name)
blobs = list(c.list_blobs(bucket))[:1]

# ----- First batch call adds duplicate user_agent spec
print("Before batch: "  + c._connection._client_info.user_agent)

try:
    # Creation of a Batch object results in another call which again appends another (duplicate) 
    # 'gcloud-python/x.xx.x' to the user_agent property.
    with c.batch()as batch:
        print("Batch context: " + batch._client_info.user_agent)
        for blob in blobs:
            blob.reload()
except g_exc.NotFound:
    pass
print("After batch: "  + c._connection._client_info.user_agent)

# ----- Subsequent batch calls continue to add more duplicates ad nauseam
for i in range(5):
    try:
        with c.batch()as batch:
            print(f"Iteration {i} - Batch context: " + batch._client_info.user_agent)
            for blob in blobs:
                blob.reload()
    except g_exc.NotFound:
        pass