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Function: Advanced DELETE operation

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      Goal: Perform the Advanced DELETE operation where Eventing interacts with the Data service.

      • This function advancedDeleteOp merely demonstrates the Advanced DELETE operation.

      • 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 === "control_adv_delete".

      • Always tries to insert the test document, any insert error will be ignored.

      • There are 4 modes of operation: no_cas, bad_cas, no_key, and good_cas.

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

      • advancedDeleteOp

      • Input Data/Mutation

      • Output Data/Log

      // To run configure the settings for this Function, advancedDeleteOp, as follows:
      //
      // Version 7.1+
      //   "Function Scope"
      //     *.* (or try bulk.data if non-privileged)
      // Version 7.0+
      //   "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"
      //
      // Version 6.6.1
      //   "Source Bucket"
      //     source
      //   "MetaData Bucket"
      //     metadata
      //   Binding(s)
      //    1. "binding type", "alias name...", "bucket",     "Access"
      //       "bucket alias", "src_col",       "source",     "read and write"
      
      function OnUpdate(doc, meta) {
          if (!meta.id.startsWith("control_adv_delete")) return;
      
          log('input meta', meta);
          log('input doc ', doc);
      
          // Setup, make sure we have our doc to "delete", ignore any errors
          couchbase.insert(src_col,{"id":"test_adv_delete:" + doc.ins_id},{"a:": 1});
      
          var new_meta;
          if (doc.mode && doc.mode === "no_cas") {
              // Here we pass no CAS it will always succeed
              new_meta = {"id":"test_adv_delete:" + doc.ins_id};
          }
          if (doc.mode && doc.mode === "bad_cas") {
              // Here we pass a non-matching CAS it will always fail
              new_meta = {"id":"test_adv_delete:" + doc.ins_id, "cas":"1111111111111111111"};
          }
          if (doc.mode && doc.mode === "good_cas") {
              // Here we will pass the matching or current CAS it will succeed
              var tmp_r = couchbase.get(src_col,{"id":"test_adv_delete:" + doc.ins_id});
              if (tmp_r.success) {
                  // Here we use the current CAS just read via couchbase.get(...)
                  new_meta = {"id":"test_adv_delete:" + doc.ins_id, "cas": tmp_r.meta.cas};
              } else {
                  log('Cannot delete due to no such key',"test_adv_delete:" + doc.ins_id);
                  return;
              }
          }
          if (doc.mode && doc.mode === "no_key") {
              // Remove (delete with a basic bucket op) so that we have: no such key
              delete src_col["test_adv_delete:" + doc.ins_id]
              new_meta = {"id":"test_adv_delete:" + doc.ins_id};
          }
          var result = couchbase.delete(src_col,new_meta);
          if (result.success) {
              log('success adv. delete: result',result);
          } else {
              log('failure adv. delete: id',new_meta.id,'result',result);
          }
      }
      Mutation #1
      
      INPUT: KEY control_adv_delete::1
      
      {
        "id": 1,
        "type": "control_adv_delete",
        "ins_id": 10,
        "mode": "no_cas"
      }
      
      Mutation #2
      
      INPUT: KEY control_adv_delete::2
      
      {
        "id": 2,
        "type": "control_adv_delete",
        "ins_id": 10,
        "mode": "bad_cas"
      }
      
      Mutation #3
      
      INPUT: KEY control_adv_delete::3
      
      {
        "id": 3,
        "type": "control_adv_delete",
        "ins_id": 10,
        "mode": "no_key"
      }
      
      Mutation #4
      
      INPUT: KEY control_adv_delete::4
      
      {
        "id": 4,
        "type": "control_adv_delete",
        "ins_id": 10,
        "mode": "good_cas"
      }

      We do four (4) deletion attempts the second fails due to a CAS missmatch and the third fails due to no such key.

      Logs from Mutation #1
      
      2021-01-08T11:45:02.897-08:00 [INFO] "input meta"
      {
          "cas": "1610134800219308032",
          "id": "control_adv_delete::1",
          "expiration": 0,
          "flags": 33554438,
          "vb": 221,
          "seq": 1
      }
      2021-01-08T11:45:02.898-08:00 [INFO] "input doc "
      {
          "id": 1,
          "type": "control_adv_delete",
          "ins_id": 10,
          "mode": "no_cas"
      }
      2021-01-08T11:45:02.899-08:00 [INFO] "success adv. delete: result"
      {
          "meta": {
              "id": "test_adv_delete:10",
              "cas": "1610135102898962432"
          },
          "success": true
      }
      
      Logs from Mutation #2
      
      2021-01-08T11:46:11.225-08:00 [INFO] "input meta"
      {
          "cas": "1610135171148152832",
          "id": "control_adv_delete::2",
          "expiration": 0,
          "flags": 33554438,
          "vb": 468,
          "seq": 3
      }
      2021-01-08T11:46:11.225-08:00 [INFO] "input doc "
      {
          "id": 2,
          "type": "control_adv_delete",
          "ins_id": 10,
          "mode": "bad_cas"
      }
      2021-01-08T11:46:11.228-08:00 [INFO] "failure adv. delete: id" "test_adv_delete:10" "result"
      {
          "error": {
              "code": 272,
              "name": "LCB_KEY_EEXISTS",
              "desc": "The document key exists with a CAS value different than specified",
              "cas_mismatch": true
          },
          "success": false
      }
      
      Logs from Mutation #3
      
      2021-01-08T11:52:51.520-08:00 [INFO] "input meta"
      {
          "cas": "1610135571485425664",
          "id": "control_adv_delete::3",
          "expiration": 0,
          "flags": 33554438,
          "vb": 723,
          "seq": 5
      }
      2021-01-08T11:52:51.520-08:00 [INFO] "input doc "
      {
          "id": 3,
          "type": "control_adv_delete",
          "ins_id": 10,
          "mode": "no_key"
      }
      2021-01-08T11:52:51.522-08:00 [INFO] "failure adv. delete: id" "test_adv_delete:10" "result"
      {
          "error": {
              "code": 272,
              "name": "LCB_KEY_ENOENT",
              "desc": "The document key does not exist on the server",
              "key_not_found": true
          },
          "success": false
      }
      
      Logs from Mutation #4
      
      2021-01-08T11:53:36.070-08:00 [INFO] "input meta"
      {
          "cas": "1610135616063602688",
          "id": "control_adv_delete::4",
          "expiration": 0,
          "flags": 33554438,
          "vb": 183,
          "seq": 3
      }
      2021-01-08T11:53:36.070-08:00 [INFO] "input doc "
      {
          "id": 4,
          "type": "control_adv_delete",
          "ins_id": 10,
          "mode": "good_cas"
      }
      2021-01-08T11:53:36.074-08:00 [INFO] "success adv. delete: result"
      {
          "meta": {
              "id": "test_adv_delete:10",
              "cas": "1610135616073760768"
          },
          "success": true
      }