AuthAzureSAS Lua Reference Documentation
chilkat.AuthAzureSAS
Current Version: 11.7.0
Markdown version of this page for AI tools (v 11.7.0) · all AI docs
Chilkat.AuthAzureSAS
Generate a signed query-string token that authorizes limited access to an
Azure Storage resource.
Provide the exact Azure SAS string-to-sign required for the storage
service and resource being accessed.
Use the Azure Storage account access key to compute the signature placed
in the generated SAS token.
Add signed SAS parameters such as permissions, expiry, resource type, API
version, protocol, or IP restrictions.
Add query parameters that should accompany the request but should not be
included as part of the SAS token itself.
Use the generated SAS query string with Azure Storage requests built
using
For an extended overview, see
AuthAzureSAS Class Overview.
Create Azure Shared Access Signature tokens for signed Azure Storage requests.
Chilkat.AuthAzureSAS creates Azure Shared Access Signature
authentication tokens. It defines the SAS string-to-sign, supplies the Azure
Storage account access key used to compute the signature, and controls which
parameters are included in the generated SAS token query string. The
resulting token can be used with Chilkat.Rest,
Chilkat.Http, or other request-building code that needs
time-limited, permission-scoped access to Azure Storage resources.
SAS token generation
String-to-sign control
Account key signing
Token parameters
Non-token parameters
REST integration
Chilkat.Rest or other Chilkat HTTP workflows.
AuthAzureSAS object, set the Azure Storage
AccessKey, provide the required StringToSign, add
SAS token parameters with SetTokenParam, add any extra query
parameters with SetNonTokenParam, then call
GenerateToken. Use AuthAzureSAS when you need a SAS
query token; use Chilkat.AuthAzureStorage when you need Shared
Key authorization headers instead.
Object Creation
local chilkat = require("chilkat")
local auth_azure_sas = chilkat.AuthAzureSAS.new()Creates the object (chilkat.AuthAzureSAS() does the same). Lua's garbage collector frees it when it is no longer referenced; auth_azure_sas:dispose() frees it at once, and in Lua 5.4 and later local auth_azure_sas <close> = chilkat.AuthAzureSAS.new() frees it when the block ends. Calling a method of a disposed object raises an error.
Errors
A method that fails returns nil followed by the error text, as io.open does: local body, err = auth_azure_sas:method(...), where err is the object's last_error_text. Wrap the call in assert() to raise an error with that text instead. Methods that answer a question return true or false, numbers are returned as they are (check last_method_success where the description says a value means failure), and property reads and writes never fail for Chilkat reasons.
Misuse raises a Lua error: a wrong argument type or a missing argument (bad argument #1 to ...), an unknown property name, a write to a read-only property, an out-of-range integer, or an object of the wrong class.
Names are Chilkat's in snake_case: QuickGetStr is quick_get_str, LastErrorText is last_error_text. Properties are fields (auth_azure_sas.verbose_logging = true) and methods use the colon (auth_azure_sas:method(...)). Strings are UTF-8; binary data is a Lua string of bytes. Indexes are 0-based, as in every Chilkat API. Unlocking: call chilkat.unlock_bundle("...") once at startup.
Properties
AccessKey
local strVal = auth_azure_sas.access_key
auth_azure_sas.access_key = strVal
This is the signing key (access key) that must be kept private. It is a base64 string such as abdTvCZFFoWUyre6erlNN+IOb9qhXgDsyhrxmZvpmxqFDwpl9oD0X9Fy0hIQa6L5UohznRLmkCtUYySO4Y2eaw==
DebugLogFilePath
local strVal = auth_azure_sas.debug_log_file_path
auth_azure_sas.debug_log_file_path = strVal
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
LastErrorHtml
local strVal = auth_azure_sas.last_error_html
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
local strVal = auth_azure_sas.last_error_text
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
local strVal = auth_azure_sas.last_error_xml
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
local boolVal = auth_azure_sas.last_method_success
auth_azure_sas.last_method_success = boolVal
Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.
StringToSign
local strVal = auth_azure_sas.string_to_sign
auth_azure_sas.string_to_sign = strVal
Defines the format of the string to sign.
The format is specified as a comma-separated list of names. For example:
signedpermissions,signedstart,signedexpiry,canonicalizedresource,signedidentifier,signedIP,signedProtocol,signedversion,rscc,rscd,rsce,rscl,rsctThis will result in an actual string-to-sign that is composed of the values for each name separated by newline (LF) chars. For example:
signedpermissions +\n+ signedstart +\n+ signedexpiry +\n+ canonicalizedresource +\n+ signedidentifier +\n+ signedIP +\n+ signedProtocol +\n+ signedversion +\n+ rscc +\n+ rscd +\n+ rsce +\n+ rscl +\n+ rsct
VerboseLogging
local boolVal = auth_azure_sas.verbose_logging
auth_azure_sas.verbose_logging = boolVal
If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
local strVal = auth_azure_sas.version
Methods
Clear
Clears all params set by the methods SetNonTokenParam and SetTokenParam.
topGenerateToken
local str, err = auth_azure_sas:generate_token()
Generates and returns the SAS token based on the defined StringToSign and params.
Returns the string, or nil, err on failure (or when nothing is found). The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.
SetNonTokenParam
-- value is a string
-- ok is true, or nil and err on failure
local ok, err = auth_azure_sas:set_non_token_param(name, value)
Adds a non-token parameter name/value. This is a value that is included in the string to sign, but is NOT included in the token query params.
Returns true on success, nil, err on failure. The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.
SetTokenParam
-- auth_param_name is a string
-- value is a string
-- ok is true, or nil and err on failure
local ok, err = auth_azure_sas:set_token_param(name, auth_param_name, value)
Adds a token parameter name/value. This is a value that is included in the string to sign, and is also included in the token query params.
Returns true on success, nil, err on failure. The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.