Solved: API Proxy with hierarchical URLs - Page 2

Report Inappropriate Content · 06-01-2015 07:07 AM

Hello, and thanks in advance for any help you guys can give me...

I'm new to API Gee and I'm in the process of creating my API.

So far, I used Baas to create a collection and a few entities underneath.

I also created an API Proxy so I can expose that.

What I want to do now, is tell the API Proxy to "mask" some of my API calls. For example, I have a shops collection and a /shops method that lists all the shops. If I want to filter by shop ID, I can add ?ql=select * where _id=1. What I want to do, is set up my Proxy so I can mask that and simply call /shops/1

How can I do that?

Thanks in advance!

Report Inappropriate Content

This can be readily done with a combination of XML and JSC based policies. In the following snippet we extract one or more catalog IDs into a variable named catalog.id as indicated above:

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<ExtractVariables async="false" continueOnError="true" enabled="true" name="extractCatalogVariables">
    <DisplayName>extractCatalogVariables</DisplayName>
    <URIPath>
    	<!-- work from most specific to least specific-->
        <Pattern>/{version}/profile/{profile.alias}/catalog/{catalog.type}/{catalog.id}/entitled</Pattern>
        <Pattern>/{version}/profile/{profile.alias}/catalog/{catalog.type}/{catalog.id}</Pattern>
    </URIPath>
    <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
</ExtractVariables>

Our convention is that multiple IDs may be concatenated with the | character. Within a Javascript callout we construct a soap snippet for selecting one or more resources as follows:

var catalog.id = context.getVariable("catalog.id");
if (!catalog.id) catalog.id = "";

var resIDs = "";
if (catalog.id !== "") {
    resIDs = "<ResourceIds>";
    var iDsArr = catalog.id.split("|");
    iDsArr.forEach(function(id) {
        resIDs += ("<ResourceId>" + id + "</ResourceId>");
    });
    resIDs += "</ResourceIds>";
}
context.setVariable("catalog.resourceQuery", resIDs);

In a subsequent AssignMessage Policy we then insert this snippet into the target request:

<AssignMessage name="buildCatalogRequestById">
    <DisplayName>buildCatalogRequestById</DisplayName>
    <AssignTo createNew="true" type="request">request</AssignTo>
    <Set>
        <Headers>
            <Header name="Authorization">{request.header.Authorization}</Header>
            <Header name="user-agent">{request.header.user-agent}</Header>
            <Header name="Cookie">{request.header.Cookie}</Header>
        </Headers>
        <Verb>POST</Verb>
        <Payload contentType="text/xml">
            <Request xmlns="urn:foo:bar">
                {catalog.identityQuery}
                <ResourcesQuery>
                    {catalog.resourceQuery}
[snip]

This can be adapted to create your back end query to BaaS as well. Generally this pattern holds anytime you want to:

create uniform or simplified proxy for a more complex or proprietary target system
transform from one API style to another (REST to SOAP)

View solution in original post