{"Msg":"IonLambdaException","Ex":{"Via":[{"Type":"java.lang.IllegalArgumentException","Message":"Key must be integer","At":["clojure.lang.APersistentVector","assoc","APersistentVector.java",347]}],"Trace":[["clojure.lang.APersistentVector","assoc","APersistentVector.java",347],["clojure.lang.APersistentVector","assoc","APersistentVector.java",18],["clojure.lang.RT","assoc","RT.java",823],["clojure.core$assoc__5401","invokeStatic","core.clj",191],["clojure.core$update","invokeStatic","core.clj",6198],["clojure.core$update","invoke","core.clj",6188],["datomic.ion.lambda.api_gateway$gateway__GT_edn","invokeStatic","api_gateway.clj",93],["datomic.ion.lambda.api_gateway$gateway__GT_edn","invoke","api_gateway.clj",87],["datomic.ion.lambda.api_gateway$edn_handler__GT_gateway_handler$fn__3198","invoke","api_gateway.clj",109],["datomic.ion.lambda.api_gateway$gateway_handler__GT_ion_handler$fn__3202","invoke","api_gateway.clj",114],["clojure.lang.Var","invoke","Var.java",384],["datomic.ion.lambda.dispatcher$fn__2154","invokeStatic","dispatcher.clj",47],["datomic.ion.lambda.dispatcher$fn__2154","invoke","dispatcher.clj",45],["clojure.lang.MultiFn","invoke","MultiFn.java",244],["datomic.ion.lambda.dispatcher$handler_fn$fn__2156","invoke","dispatcher.clj",61],["datomic.clojio$start_server$socket_loop__2356$fn__2360","invoke","clojio.clj",204],["datomic.clojio$start_server$socket_loop__2356","invoke","clojio.clj",203],["datomic.clojio$start_server$accept_loop__2363$fn__2364","invoke","clojio.clj",219],["clojure.core$binding_conveyor_fn$fn__5739","invoke","core.clj",2030],["clojure.lang.AFn","call","AFn.java",18],["java.util.concurrent.FutureTask","run","FutureTask.java",266],["java.util.concurrent.ThreadPoolExecutor","runWorker","ThreadPoolExecutor.java",1149],["java.util.concurrent.ThreadPoolExecutor$Worker","run","ThreadPoolExecutor.java",624],["java.lang.Thread","run","Thread.java",748]],"Cause":"Key must be integer"},"Type":"Event","Tid":1075,"Timestamp":1575271105341}

You are calling update on a vector using a non-integer key

I know what the exception means, it is not coming from my code, but datomic's

but it seems in this case it was due to trying to call the lambda with aws cli, instead of thru api gw