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Sage 300c Web Services

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Introduction

Hand in hand with true HTML/JavaScript/CSS Web UI’s you also want to access the same logic from other general programs using RESTful Web Services. This gives a general API to access the application which doesn’t require any Sage 300 components be installed on the client computer and doesn’t require the calling application be on the same computer or even at the same location.

ASP.Net MVC Web screens tend to have quite quickly changing interfaces between the Views, Controllers and Models which makes using then same Web Services as the UI a bit problematic, especially as the screens evolve quickly. You want a stable Web Services interface that preserves compatibility from version to version and provides a wider more general interface. At the same time the developer of an ASP.Net MVC program doesn’t want to do a completely different implementation for exposing Web Services.

The way ASP.Net MVC solves this dilemma is by allowing you to add a Web Services stack on top of your existing models (which in our case means fully leveraging the business repositories and Sage 300 Business Logic as well). But it uses a custom controller to handle the Web Services requests. In the Microsoft stack there are several supported standards for Web Services, but the one we used is OData. This means that using our Web Services you can do all the standard OData queries and supports the standard OData meta-data.

With our Sage 300 2016 Product Update 1 we have included a number of Web Services in the product. These are automatically installed if you select the Web UIs option from the main installation. So if the Web UIs are up and running then you can try playing with the Web Services. In this article we’ll show how to get started using these. Over next couple of releases, we’ll be fleshing these out to support all the Business logic as well as services beyond the basic CRUD operations.

Some Examples

If you type:

https://yourservername/Sage300webapi/sdata/-/SAMLTD/GL/Accounts

into the Chrome browser you will be prompted for your Sage 300 login credentials, which you can enter. Note that from this browser prompt the password is case sensitive, so you need to uppercase your normal Sage 300 password (since our regular login screen normally does this).

webserv1

Then after entering the correct data you will get back a JSON object with all the information in your chart of Accounts (including details like optional fields):

webserv2

Working with the Browser directly, although fun, will soon become tedious. Another easier approach is to install the Chrome add-in PostMan which will remember your Web Services so you can adjust and repeat them. You need to set the Basic Authorization header with your Sage 300 login and password. Below we use the shortened URL to get the list of all the available feeds for SAMLTD with the URL:

https://yourservername/Sage300webapi/sdata/-/SAMLTD

using PostMan:

webserv3

And we get the returned JSON object containing the list of Web Services we support. It by company since not all accounting application may be activated in the database.

Queries

You can do standard OData queries to filter the returned data. For instance:

https://yourservername/Sage300webapi/sdata/-/SAMLTD/GL/Accounts?$filter=UnformattedAccount eq ‘1020’

will result in just this one account being returned:

webserv4

The way we implement queries is via adding LINQ support that will convert the LINQ query to a Browse filter for our Sage 300 View. This means we will support any query as long as we can translated it into a Browse filter. If the filter contains a SQL function we don’t support, then you will get back a not supported error for your query. Note that often people writing code for the regular Web UIs just use our C# LINQ support to browse/fetch rather than calling browse/fetch directly since this lets you leverage other advanced features in C# and .Net.

Other Clauses

You can specify a sort order as long as what you requests matches an index in the Sage 300 database:

https://yourservername/Sage300webapi/sdata/-/SAMLTD/GL/Accounts?$orderby=UnformattedAccount desc

webserv5

You can specify to get the top n records or to skip n records via:

https://yourservername/Sage300webapi/sdata/-/SAMLTD/GL/Accounts?$top=2

https://yourservername/Sage300webapi/sdata/-/SAMLTD/GL/Accounts?$skip=2

which is useful to page data.

Meta Data

You can get meta data for all the feeds using the $metadata tag. For instance:

https://yourservername/Sage300webapi/sdata/-/SAMLTD/$metadata

will return the meta data for all the feeds that are relevant for SAMLTD:

webserv6

(Note that this is quite a large JSON object to process).

Updating/Inserting/Deleting

This initial implementation includes sufficient G/L feeds for supporting financial reporting. Hence these G/L feeds are read only at this point. We do support inserting G/L Batches, O/E Orders and A/R Customers. Many of the non-G/L feeds support updating, inserting and deleting. If the entity supports these then you can delete the record by specifying DELETE as the HTTP verb (which is easy in PostMan), similarly insert if via POST and update if via PUT or PATCH.

Generally, the best way to figure out the format of the payload to include with these is to do a GET and then use that payload as a template to build the JSON object with the data you want to update or insert.

Since these Web APIs are built on the Sage 300 Business Logic all the usual validation will take place and you will get back Sage 300 error messages in the response payload if the request fails.

Troubleshooting

Ideally the responses from the server will include error messages to tell you what went wrong, so always check these. If they aren’t helpful, then on your web server check the Web API trace log which is located at:

Sage300InstallDir/Online/WebApi/Logs/trace.log

This will usually have the raw error when something has gone wrong.

If you don’t see anything in either of these places, perhaps check your IIS log to make sure that the request didn’t get rejected for some other reason. Especially remember to include your basic authorization header.

Security

If you expose your Web Services to the general Internet, ensure that you follow all the security measures in this article. You will need to do this if you are integrating with an external cloud service or other client located outside your network. Generally, you want to keep your Web Service communications private, so they can’t be accessed by hackers or spied on by hackers. Using good practices around enforcing HTTPS is crucial here.

Summary

The set of Web Services included in the Sage 300 2016 Product Update 1 are intended to support Financial Reporting on General Ledger as well as basic e-Commerce functionality like accessing Customers and entering Orders. Part of the intent of this release is to let people play with these and provide feedback as we move to complete out the full set of Web Services for our next version.

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Written by smist08

February 15, 2016 at 11:26 pm