Merge pull request #306 from jetstack/refactoring-III

In order to reduce the memory usage we are going substitute golang json encoder library with https://github.com/json-iterator/go, from pprof we can both Marshalling and Unmarshalling hug much of the cumulative memory.

Author: Oluwole Fadeyi

go.mod

@@ -39,6 +39,7 @@ require (
 	k8s.io/api v0.20.1
 	k8s.io/apimachinery v0.20.1
 	k8s.io/client-go v11.0.0+incompatible
+	github.com/json-iterator/go v1.1.12
 	k8s.io/utils v0.0.0-20201110183641-67b214c5f920
 	sigs.k8s.io/yaml v1.3.0
 )

go.sum

@@ -581,6 +581,8 @@ github.com/json-iterator/go v1.1.7/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/u
 github.com/json-iterator/go v1.1.8/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.10 h1:Kz6Cvnvv2wGdaG/V8yMvfkmNiXq9Ya2KUv4rouJJr68=
 github.com/json-iterator/go v1.1.10/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
+github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
+github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
@@ -697,6 +699,8 @@ github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJ
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9AWI=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
+github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
+github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/morikuni/aec v1.0.0/go.mod h1:BbKIizmSmc5MMPqRYbxO4ZU0S0+P200+tUnFx7PXmsc=
 github.com/munnerz/goautoneg v0.0.0-20120707110453-a547fc61f48d/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=

pkg/agent/run.go

@@ -3,7 +3,6 @@ package agent
 import (
 	"bytes"
 	"context"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -23,6 +22,7 @@ import (
 	"github.com/jetstack/preflight/pkg/datagatherer"
 	dgerror "github.com/jetstack/preflight/pkg/datagatherer/error"
 	"github.com/jetstack/preflight/pkg/version"
+	json "github.com/json-iterator/go"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/spf13/cobra"
 )

pkg/datagatherer/k8s/fieldfilter.go

@@ -1,11 +1,11 @@
 package k8s
 
 import (
-	"encoding/json"
 	"fmt"
 	"strings"
 
 	"github.com/Jeffail/gabs/v2"
+	json "github.com/json-iterator/go"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 )