TChilkatAuthAws Delphi ActiveX Reference Documentation
Current Version: 220.127.116.11
Implements AWS Signature V4 for signing and authenticating AWS REST requests.
Importing the Chilkat ActiveX into Delphi
Important: When upgrading to a new version of Chilkat, make sure to re-imported ActiveX DLL into Delphi to regenerate the files described below.
Two things are required to use an ActiveX in Delphi:
- The ActiveX DLL needs to be registered via regsvr32 on the system where the Delphi application runs. See How To Register ActiveX DLLs for detailed information.
- See also: ActiveX Registration Tutorial
- The ActiveX component needs to be "imported". Use the Delphi Import Component Wizard to import the Chilkat type library. This creates the following files: Chilkat_v9_5_0_TLB.pas and Chilkat_v9_5_0_TLB.dcr. The Chilkat_v9_5_0_TLB.pas should be added to your project.
To import the Chilkat type library, do the following:
- In the Delphi RAD Studio, select the menu item "Component" --> "Import a Type Library".
- Find "Chilkat ActiveX v9.5.0" in the list and select it. This will only appear in the list if the ChilkatAx-9.5.0-win32.dll (or ChilkatAx-9.5.0-x64.dll) has been registered w/ regsvr32.
- Check the "Generate Component Wrappers" checkbox.
- Select a directory where the unit files (.pas and .dcr) should be generated.
- Select "Create Unit" and then "Finish".
- Add the .pas to your Delphi project.
To use a Chilkat ActiveX object in your Delphi code, add "Chilkat_v9_5_0_TLB" to the "uses" statement. For example:
uses Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_v9_5_0_TLB;
var obj: TChilkatAuthAws; ... begin obj := TChilkatAuthAws.Create(Self); ... // When finished, free the object instance. obj.Free();
The AWS access key.top
If AWS Signature Version V2 is used, then this property must be set. The rules for setting the canonicalized resource for the V2 signature method is described here: Constructing the CanonicalizedResource Element.
If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.
This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:
- a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
- the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
- there is an internal problem (bug) in the Chilkat code that causes the hang.
The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).top
Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.top
Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.top
Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.top
Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:
- Any method that returns a string.
- Any method returning a Chilkat object, binary bytes, or a date/time.
- Any method returning a standard boolean status value where success = 1 and failure = 0.
- Any method returning an integer where failure is defined by a return value less than zero.
Note: Methods that do not fit the above requirements will always set this property equal to 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.top
The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).
The length, in characters, of the string contained in the LastStringResult property.top
This property can optionally be set for AWS requests that have a non-empty request body. This should be the base64 encoding of the 16 bytes of the MD5 hash. The most common need for this is if doing an S3 upload from a stream. (If the pre-computed MD5 is not provided, then Chilkat is forced to stream the entire file into memory so that it can calculate the MD5 for authentication.)
Note: AWS Signature Version 2 uses the MD5, whereas Signature Version 4 uses SHA256.top
This property can optionally be set for AWS requests that have a non-empty request body. This should be the lowercase hex encoding of the 32-bytes of the SHA256 hash. The most common need for this is if doing an S3 upload from a stream. (If the pre-computed SHA-256 is not provided, then Chilkat is forced to stream the entire file into memory so that it can calculate the SHA-256 for authentication.)
Note: AWS Signature Version 4 uses the SHA256 hash. (AWS Signature Version 2 uses MD5)
The AWS region, such as "us-east-1", "us-west-2", "eu-west-1", "eu-central-1", etc. The default is "us-east-1". It is only used when the SignatureVersion property is set to 4. This property is unused when the SignatureVersion property is set to 2.top
The AWS secret key.top
The AWS service namespace, such as "s3", "ses", etc. See http://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html#genref-aws-service-namespaces
This property is unused when the SignatureVersion property is set to 2.top
The AWS Signature Version to be used in authentication. The default value is 4. This can optionally be set to the value 2 to use the older V2 signature version.top
If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.top
Version of the component/library, such as "18.104.22.168"top
Generates a temporary pre-signed URL for an Amazon AWS service using AWS Signature V4. Requires that the SecretKey, AccessKey, and Region properties be set to valid values prior to calling this method.
The URL that is generated has this format:
https://<domain>/<path> ?X-Amz-Algorithm=AWS4-HMAC-SHA256 &X-Amz-Credential=<AccessKey>/<currentDate>/<Region>/<awsService>/aws4_request &X-Amz-Date=<currentDateTime> &X-Amz-Expires=<numSecondsValid> &X-Amz-SignedHeaders=host &X-Amz-Signature=<signature-value>
The httpVerb is the HTTP verb such as "GET", "PUT", "POST", "DELETE", etc. The awsService is a string naming the AWS service, such as "s3", "execute-api", etc. If useHttps is 1, then the returned URL begins with "https://", otherwise it begins with "http://".
Returns a zero-length WideString on failuretop