Recap of Part 7

We finished Part 7 of this document series by looking at the different processing segments and stages into which API Management divides the request/response cycle.

This is very important to understand because when we now look at the tool called the API Policy Designer, the graphical display will only show us one processing stage of one segment.

Remember, the overall request/response cycle has the following segments and processing stages.

But now, when we start using the API Policy Designer, at any one time, we will only be looking at a subset of these processing stages.  Therefore we need to spend some time looking at exactly how the Policy Designer display this data.  Without this knowledge, using the Policy Designer might become somewhat confusing.

The API Policy Designer

Log on to your API Portal.  From the Manage menu option, select the GWSAMPLE_BASIC API Proxy.  Towards the top right of the screen, there is the “Policies” option.  Click here to start the Policy Designer.

Since we have not yet assigned any policies to any processing stages, the display will look like this

Remember that down the left side of the screen, there is a tree menu called Flows.  just to orientate yourself, collapse the ProxyEndpoint and TargetEndpoint tree nodes.

When you select any processing stage belonging to the ProxyEndpoint segment, you are immediately focussing on only the policies assigned to this one segment.

In other words, you are focussing on these processing stages.

Similarly, when you select the TargetEndpoint…

You are focussing only on these processing stages.

Let’s now further narrow the focus by expanding the ProxyEndpoint node in the tree menu and selecting the Preflow processing stage.

In your scenario, you will see zero next to Preflow and not 3.  This is just because I’m taking screen screen shots from an API Proxy in which 3 policies have already been assigned to the Preflow stage of the Proxy Endpoint segment.

Having made this selection, the graphical display shows us only the policies assigned to these stages

Select PostFlow…

And now the graphical display shows us only the policies assigned to these stages

Finally, select one of the Condition Flows…

And now the graphical display shows us only the policies assigned to these stages

You get the idea…

So going back to the PreFlow example used above, the graphical editor will show us this.  (Don’t worry that your display does not show you this – we’ll fix this in the next document)

Based on the selection of PreFlow underneath ProxyEndpoint from the tree menu on the left, the editor now shows us only those policies assigned to the PreFlow processing stage of the ProxyEndpoint segment.

Similarly, by selecting PostFlow underneath ProxyEndpoint segment, the editor now shows us only those policies assigned to this processing stage of the selected segment.

So now that we understand what the editor is showing us, we can now proceed to assign some policies to the various processing stages within each segment.

Part 9 – Assigning Policies to an API Proxy

Chris W