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Tcl

Manage Cloud Storage Bucket Labels

See more Google Cloud Storage Examples

Demonstrates how to add, update, and delete labels for a Cloud Storage bucket.

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

set success 0

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# This example uses a previously obtained access token having permission for the 
# scope "https://www.googleapis.com/auth/cloud-platform"

# In this example, Get Google Cloud Storage OAuth2 Access Token, 
# the service account access token was saved to a text file.  This example fetches the access token from the file..
set sbToken [new_CkStringBuilder]

CkStringBuilder_LoadFile $sbToken "qa_data/tokens/googleCloudStorageAccessToken.txt" "utf-8"

# ---- Step 1
# Create the JSON body of the PATCH request that will be sent.
# This specifies labels to be added, updated, and/or deleted.
# (To delete a label, set its value equal to null.)

# {
#   "labels": {
#     "new_label_key": "new_label_value",
#     "existing_label_key": "updated_label_value",
#     "old_label_key": null
#   }
# }

# ---------
# Important
# ---------
# You can apply multiple labels to each bucket, with a maximum of 64 labels per bucket.

#     - Keys and values cannot be longer than 63 characters each.
#     - Keys and values can only contain lowercase letters, numeric characters, underscores, and dashes. International characters are allowed.
#     - Label keys must start with a lowercase letter and international characters are allowed.
#     - Label keys cannot be empty.

# Build JSON to update labels.
# 
# During the testing of this example, my bucket already has the following labels:
# {
#  "labels": {
#   "test1": "xyz",
#   "test": "abc",
#   "a": "abc"
#  }
# }

# For this example, I'm going to add a label "b", delete the label "test1", and update
# the label "test".
set json [new_CkJsonObject]

CkJsonObject_UpdateString $json "labels.b" "bbb"
CkJsonObject_UpdateString $json "labels.test" "abc123"
CkJsonObject_UpdateNull $json "labels.test1"

# ---- Step 2
# Send a PATCH equivalent to this curl command

# curl -X PATCH --data-binary @[JSON_FILE_NAME].json \
#     -H "Authorization: Bearer [OAUTH2_TOKEN]" \
#     -H "Content-Type: application/json" \
#     "https://www.googleapis.com/storage/v1/b/[BUCKET_NAME]?fields=labels"

set http [new_CkHttp]

CkHttp_put_AuthToken $http [CkStringBuilder_getAsString $sbToken]

CkHttp_SetUrlVar $http "bucket_name" "chilkat-ocean"
set url "https://www.googleapis.com/storage/v1/b/{$bucket_name}?fields=labels"
set resp [new_CkHttpResponse]

set success [CkHttp_HttpJson $http "PATCH" $url $json "application/json" $resp]
if {$success == 0} then {
    puts [CkHttp_lastErrorText $http]
    delete_CkStringBuilder $sbToken
    delete_CkJsonObject $json
    delete_CkHttp $http
    delete_CkHttpResponse $resp
    exit
}

set responseCode [CkHttpResponse_get_StatusCode $resp]
if {$responseCode == 401} then {
    puts [CkHttpResponse_bodyStr $resp]
    puts "If invalid credentials, then it is likely the access token expired."
    puts "Your app should automatically fetch a new access token and re-try."
    delete_CkStringBuilder $sbToken
    delete_CkJsonObject $json
    delete_CkHttp $http
    delete_CkHttpResponse $resp
    exit
}

# Note: A 400 response code is likely caused by illegal characters used for a label name and/or value.

puts "Response code: $responseCode"
puts "Response body"
puts [CkHttpResponse_bodyStr $resp]

# A response code = 200 indicates success, and the response body contains the JSON
# for the new/updated set of labels
# Response code: 200
# Response body
# {
#  "labels": {
#   "test": "abc123",
#   "a": "abc",
#   "b": "bbb"
#  }
# }

delete_CkStringBuilder $sbToken
delete_CkJsonObject $json
delete_CkHttp $http
delete_CkHttpResponse $resp