Function: Advanced GET operation (with cache)

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    Couchbase Server 7.0.2 Goal: Perform the Advanced GET operation where Eventing interacts with the Data service.

    • This function advancedGetOpWithCache merely demonstrates the Advanced GET operation with Bucket Backed Cache enabled.

    • Requires Eventing Storage (or metadata collection) and a "source" collection.

    • Needs a Binding of type "bucket alias" (as documented in the Scriptlet).

    • Will operate on any mutation where doc.type === "test_adv_get".

    • The optional third parameter to couchbase.get of {"cache": true} enables caching of documents for up to 1 second.

    • This RYOW caching is 18X-25X faster than reading near static data directly from the Data Service (or KV).

    • For more information refer to Advanced GET operation in the detailed documentation.

    • advancedGetOpWithCache

    • Input Data/Mutation

    • Output Data/Logged

    // To run configure the settings for this Function, advancedGetOpWithCache, as follows:
    //
    // Version 7.1+
    //   "Function Scope"
    //     *.* (or try bulk.data if non-privileged)
    // Version 7.0.2+
    //   "Listen to Location"
    //     bulk.data.source
    //   "Eventing Storage"
    //     rr100.eventing.metadata
    //   Binding(s)
    //    1. "binding type", "alias name...", "bucket.scope.collection", "Access"
    //       "bucket alias", "src_col",       "bulk.data.source",        "read and write"
    
    function OnUpdate(doc, meta) {
        // filter out non-intersting documents
        if (!doc.type || doc.type !== "test_adv_get") return;
        log('input doc ', doc);
        log('input meta', meta);
        // let's read the same item and then try to read a non existent item
        var meta_ary = [{"id":"test_adv_get::1"}, {"id":"not_present::1"}];
        for (var i = 0; i < meta_ary.length; i++) {
            var result = couchbase.get(src_col,meta_ary[i],{"cache": true});
            if (result.success) {
                log('success adv. get with cache: result',result);
            } else {
                log('failure adv. get with cache: id',meta_ary[i].id,'result',result);
            }
        }
    }
    INPUT: KEY test_adv_get::1
    
    {
        "id": 1,
        "type": "test_adv_get"
    }
    2021-10-04T15:54:31.101-07:00 [INFO] "input doc " {
    	"id": 1,
    	"type": "test_adv_get"
    }
    2021-10-04T15:54:31.101-07:00 [INFO] "input meta" {
    	"cas": "1633388049399873536",
    	"id": "test_adv_get::1",
    	"expiration": 0,
    	"flags": 33554438,
    	"vb": 324,
    	"seq": 3,
    	"datatype": "json"
    }
    2021-10-04T15:54:31.102-07:00 [INFO] "success adv. get with cache: result" {
    	"doc": {
    		"id": 1,
    		"type": "test_adv_get"
    	},
    	"meta": {
    		"id": "test_adv_get::1",
    		"cas": "1633388049399873536",
    		"datatype": "json"
    	},
    	"success": true
    }
    2021-10-04T15:54:31.102-07:00 [INFO] "failure adv. get with cache: id" "not_present::1" "result" {
    	"error": {
    		"code": 1,
    		"name": "LCB_KEY_ENOENT",
    		"desc": "The document key does not exist on the server",
    		"key_not_found": true
    	},
    	"success": false
    }