Question Re: Our experiences using SQLA HTTPS webclient in Technology Q&A

Our experiences using SQLA HTTPS webclient

PCollins — Tue, 02 May 2023 13:17:51 GMT

This more a post of observations we have following successfully deploying the SQLA webclient to communicate with a third party webserver as most of the information we found was out of date:

1) Sybase 17.0.11 on Windows uses the operating systems certificate store, provided the server is using a public CA there is no need to declare the certificate in the Procedure.

2) Remember to set "type 'HTTPS:POST'" rather then HTTP:POST or HTTP:GET etc

3) Set the header "Connection:keep-alive" otherwise you may get intermittent exception WW059 "The secure connection to the remote host failed: The connection was closed from the other side"

4) You probably want to ensure you use "set 'HTTP(EXCEPTIONS=off; VERSION=1.1)'"

5) set option "remote_idle_timeout", it defaults at 15 seconds which is no good, we have gone for 180 seconds

The above has certainly given us a rock solid https client which communicates with third parties nicely.

Re: Our experiences using SQLA HTTPS webclient

VolkerBarth — Wed, 03 May 2023 03:35:19 GMT

2) Remember to set "type 'HTTPS:POST'" rather then HTTP:POST or HTTP:GET etc

Are you sure on that? According to the 17.0.1. docs type is restricted to HTTP (or SOAP). We do use HTTP but provide an URL with https: for secure connections.

Great suggestions, anyway! FWIW, we have not needed to increase the default remote_idle_timeout value, probably as most web services are hosted locally.

Re: Our experiences using SQLA HTTPS webclient

PCollins — Wed, 03 May 2023 03:48:29 GMT

Yes, this tripped us up for awhile and we were getting inconsistent connections but if you read the examples on that page it shows using HTTPS:POST in a couple of the examples so we tried it and haven't reverted back.

The timeout issue is very much dependent on the servers, we didn't come across it as a problem when testing locally for sure and it really depends on the load of the server, some third parties servers don't get impacted, same again with "Connection:keep-alive"

Re: Our experiences using SQLA HTTPS webclient

VolkerBarth — Wed, 03 May 2023 04:03:32 GMT

Yes, I asked on the doc page for further clarification between the syntax description and the samples... (The 17.0.0 docs do have TYPE 'HTTPS:POST...' in their samples, too.)

Re: Our experiences using SQLA HTTPS webclient

VolkerBarth — Fri, 05 May 2023 06:36:30 GMT

Just to add: To understand and check requests and responses, particularly for newly embedded web services, we usually have to turn on "Web client logging debugging" temporarily, as described here.

FWIW, the usage of this feature via "dbsrvX -zoc MyWebClientLog.txt" or

call sa_server_option('WebClientLogFile', 'MyWebClientLog.txt');
call sa_server_option('WebClientLogging', 'On');

has not changed for newer versions.

Re: Our experiences using SQLA HTTPS webclient

PCollins — Fri, 05 May 2023 06:41:37 GMT

Yes, this was also useful.