Add collection function

go.mod

@@ -14,10 +14,13 @@ require (
 	github.com/gogo/protobuf v1.3.2
 	github.com/golang/mock v1.5.0
 	github.com/golang/protobuf v1.4.3
+	github.com/gookit/goutil v0.3.15
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0
 	github.com/hashicorp/go-hclog v0.0.0-20180709165350-ff2cf002a8dd
+	github.com/hashicorp/go-multierror v1.1.0
 	github.com/hashicorp/go-plugin v1.3.0
 	github.com/ipfs/go-cid v0.0.7
+	github.com/lestrrat-go/file-rotatelogs v2.2.0+incompatible
 	github.com/libp2p/go-libp2p-core v0.6.1
 	github.com/meshplus/bitxhub-core v1.3.1-0.20210524071255-789fd9ab501c
 	github.com/meshplus/bitxhub-kit v1.2.1-0.20210524063043-9afae78ac098
@@ -25,6 +28,7 @@ require (
 	github.com/meshplus/go-lightp2p v0.0.0-20200817105923-6b3aee40fa54
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/multiformats/go-multiaddr v0.3.0
+	github.com/rifflock/lfshook v0.0.0-20180920164130-b9218ef580f5
 	github.com/sirupsen/logrus v1.6.0
 	github.com/spf13/viper v1.7.0
 	github.com/stretchr/testify v1.7.0
@@ -49,10 +53,10 @@ require (
 	github.com/google/uuid v1.1.2 // indirect
 	github.com/gorilla/websocket v1.4.2 // indirect
 	github.com/hashicorp/errwrap v1.0.0 // indirect
-	github.com/hashicorp/go-multierror v1.1.0 // indirect
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb // indirect
+	github.com/huandu/xstrings v1.3.2 // indirect
 	github.com/huin/goupnp v1.0.0 // indirect
 	github.com/ipfs/go-datastore v0.4.4 // indirect
 	github.com/ipfs/go-ipfs-util v0.0.1 // indirect
@@ -63,11 +67,10 @@ require (
 	github.com/jbenet/go-temp-err-catcher v0.1.0 // indirect
 	github.com/jbenet/goprocess v0.1.4 // indirect
 	github.com/joho/godotenv v1.3.0 // indirect
-	github.com/json-iterator/go v1.1.9 // indirect
+	github.com/json-iterator/go v1.1.11 // indirect
 	github.com/konsorten/go-windows-terminal-sequences v1.0.3 // indirect
 	github.com/koron/go-ssdp v0.0.0-20191105050749-2e1c40ed0b5d // indirect
 	github.com/leodido/go-urn v1.2.0 // indirect
-	github.com/lestrrat-go/file-rotatelogs v2.2.0+incompatible // indirect
 	github.com/lestrrat-go/strftime v1.0.0 // indirect
 	github.com/libp2p/go-addr-util v0.0.2 // indirect
 	github.com/libp2p/go-buffer-pool v0.0.2 // indirect
@@ -131,18 +134,18 @@ require (
 	github.com/pelletier/go-toml v1.2.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/rifflock/lfshook v0.0.0-20180920164130-b9218ef580f5 // indirect
 	github.com/rogpeppe/go-internal v1.3.0 // indirect
 	github.com/russross/blackfriday/v2 v2.0.1 // indirect
 	github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
 	github.com/spacemonkeygo/spacelog v0.0.0-20180420211403-2296661a0572 // indirect
 	github.com/spaolacci/murmur3 v1.1.0 // indirect
 	github.com/spf13/afero v1.1.2 // indirect
-	github.com/spf13/cast v1.3.0 // indirect
+	github.com/spf13/cast v1.4.1 // indirect
 	github.com/spf13/jwalterweatherman v1.0.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/subosito/gotenv v1.2.0 // indirect
 	github.com/syndtr/goleveldb v1.0.1-0.20210305035536-64b5b1c73954 // indirect
+	github.com/thoas/go-funk v0.9.1 // indirect
 	github.com/tidwall/match v1.0.3 // indirect
 	github.com/tidwall/pretty v1.0.2 // indirect
 	github.com/ugorji/go/codec v1.1.7 // indirect
@@ -152,7 +155,7 @@ require (
 	go.uber.org/atomic v1.6.0 // indirect
 	go.uber.org/multierr v1.5.0 // indirect
 	go.uber.org/zap v1.15.0 // indirect
-	golang.org/x/crypto v0.0.0-20201117144127-c1f2f97bffc9 // indirect
+	golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad // indirect
 	golang.org/x/net v0.0.0-20201021035429-f5854403a974 // indirect
 	golang.org/x/sys v0.0.0-20210909193231-528a39cd75f3 // indirect
 	golang.org/x/text v0.3.3 // indirect

go.sum

@@ -258,6 +258,9 @@ github.com/google/uuid v1.1.2 h1:EVhdT+1Kseyi1/pUmXKaFxYsDNy9RQYkMWRH68J/W7Y=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
+github.com/gookit/color v1.4.2/go.mod h1:fqRyamkC1W8uxl+lxCQxOT09l/vYfZ+QeiX3rKQHCoQ=
+github.com/gookit/goutil v0.3.15 h1:nfMiE1nlBES16zOsLzNeR/vo6a7KlV58womgG6dB+JM=
+github.com/gookit/goutil v0.3.15/go.mod h1:2w7h+/CB6n2m4qzECHj6+TOmMR8q7ierD9+LyybGy3I=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1 h1:EGx4pi6eqNxGaHF6qqu48+N2wcFQ5qg5FXgOdqsJ5d8=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/context v1.1.1/go.mod h1:kBGZzfjB9CEq2AlWe17Uuf7NDRt0dE0s8S51q0aT7Yg=
@@ -317,6 +320,8 @@ github.com/hashicorp/serf v0.8.2/go.mod h1:6hOLApaqBFA1NXqRQAsxw9QxuDEvNxSQRwA/J
 github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb h1:b5rjCoWHc7eqmAS4/qyk21ZsHyb6Mxv/jykxvNTkU4M=
 github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb/go.mod h1:+NfK9FKeTrX5uv1uIXGdwYDTeHna2qgaIlx54MXqjAM=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
+github.com/huandu/xstrings v1.3.2 h1:L18LIDzqlW6xN2rEkpdV8+oL/IXWJ1APd+vsdYy4Wdw=
+github.com/huandu/xstrings v1.3.2/go.mod h1:y5/lhBue+AyNmUVz9RLU9xbLR0o4KIIExikq4ovT0aE=
 github.com/hudl/fargo v1.3.0/go.mod h1:y3CKSmjA+wD2gak7sUSXTAoopbhU08POFhmITJgmKTg=
 github.com/huin/goupnp v1.0.0 h1:wg75sLpL6DZqwHQN6E1Cfk6mtfzS45z8OV+ic+DtHRo=
 github.com/huin/goupnp v1.0.0/go.mod h1:n9v9KO1tAxYH82qOn+UTIFQDmx5n1Zxd/ClZDMX7Bnc=
@@ -397,8 +402,9 @@ github.com/jrick/logrotate v1.0.0/go.mod h1:LNinyqDIJnpAur+b8yyulnQw/wDuN1+BYKlT
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/json-iterator/go v1.1.7/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.8/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
-github.com/json-iterator/go v1.1.9 h1:9yzud/Ht36ygwatGx56VwCZtlI/2AD15T1X2sjSuGns=
 github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
+github.com/json-iterator/go v1.1.11 h1:uVUAXhF2To8cbw/3xN3pxj6kk7TYKs98NIrTqPlMWAQ=
+github.com/json-iterator/go v1.1.11/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7C0MuV77Wo=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
@@ -605,8 +611,8 @@ github.com/mattn/go-isatty v0.0.4/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNx
 github.com/mattn/go-isatty v0.0.5/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.10/go.mod h1:qgIWMr58cqv1PHHyhnkY9lrL7etaEgOFcMEpPG5Rm84=
-github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
+github.com/mattn/go-isatty v0.0.13/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
 github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/mattn/go-runewidth v0.0.2/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
@@ -842,6 +848,8 @@ github.com/spf13/afero v1.1.2 h1:m8/z1t7/fwjysjQRYbP0RD+bUIF/8tJwPdEZsI83ACI=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/cast v1.3.0 h1:oget//CVOEoFewqQxwr0Ej5yjygnqGkvggSE/gB35Q8=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
+github.com/spf13/cast v1.4.1 h1:s0hze+J0196ZfEMTs80N7UlFt0BDuQ7Q+JDnHiMWKdA=
+github.com/spf13/cast v1.4.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0 h1:XHEdyB+EcvlqZamSM4ZOMGlc93t6AcsBEu9Gc1vn7yk=
@@ -865,6 +873,7 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.6.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0 h1:Slr1R9HxAlEKefgq5jn9U+DnETlIUa6HfgEzj0g5d7s=
@@ -876,6 +885,8 @@ github.com/syndtr/goleveldb v1.0.1-0.20210305035536-64b5b1c73954 h1:xQdMZ1WLrgkk
 github.com/syndtr/goleveldb v1.0.1-0.20210305035536-64b5b1c73954/go.mod h1:u2MKkTVTVJWe5D1rCvame8WqhBd88EuIwODJZ1VHCPM=
 github.com/tebeka/strftime v0.1.3 h1:5HQXOqWKYRFfNyBMNVc9z5+QzuBtIXy03psIhtdJYto=
 github.com/tebeka/strftime v0.1.3/go.mod h1:7wJm3dZlpr4l/oVK0t1HYIc4rMzQ2XJlOMIUJUJH6XQ=
+github.com/thoas/go-funk v0.9.1 h1:O549iLZqPpTUQ10ykd26sZhzD+rmR5pWhuElrhbC20M=
+github.com/thoas/go-funk v0.9.1/go.mod h1:+IWnUfUmFO1+WVYQWQtIJHeRRdaIyyYglZN7xzUPe4Q=
 github.com/tidwall/gjson v1.6.8 h1:CTmXMClGYPAmln7652e69B7OLXfTi5ABcPPwjIWUv7w=
 github.com/tidwall/gjson v1.6.8/go.mod h1:zeFuBCIqD4sN/gmqBzZ4j7Jd6UcA2Fc56x7QFsv+8fI=
 github.com/tidwall/match v1.0.3 h1:FQUVvBImDutD8wJLN6c5eMzWtjgONK9MwIBCOrUJKeE=
@@ -916,6 +927,7 @@ github.com/whyrusleeping/multiaddr-filter v0.0.0-20160516205228-e903e4adabd7/go.
 github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c/go.mod h1:lB8K/P019DLNhemzwFU4jHLhdvlE6uDZjXFejJXr49I=
 github.com/xdg/stringprep v1.0.0/go.mod h1:Jhud4/sHMO4oL310DaZAKk9ZaJ08SJfe+sJh0HrGL1Y=
 github.com/xiang90/probing v0.0.0-20190116061207-43a291ad63a2/go.mod h1:UETIi67q53MR2AWcXfiuqkDkRtnGDLqkBTpCHuJHxtU=
+github.com/xo/terminfo v0.0.0-20210125001918-ca9a967f8778/go.mod h1:2MuV+tbUrU1zIOPMxZ5EncGwgmMJsa+9ucAQZXxsObs=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
@@ -967,8 +979,9 @@ golang.org/x/crypto v0.0.0-20200221231518-2aa609cf4a9d/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20200311171314-f7b00557c8c4/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200510223506-06a226fb4e37/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.0.0-20201117144127-c1f2f97bffc9 h1:phUcVbl53swtrUN8kQEXFhUxPlIlWyBfKmidCu7P95o=
 golang.org/x/crypto v0.0.0-20201117144127-c1f2f97bffc9/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
+golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad h1:DN0cp81fZ3njFcrLCytUHRSUkqBjfTo4Tx9RJTWs0EY=
+golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190510132918-efd6b22b2522/go.mod h1:ZjyILWgesfNpC6sMxTJOJm9Kp84zZh5NQWvqDGG3Qr8=
@@ -1083,8 +1096,8 @@ golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200519105757-fe76b779f299/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f h1:+Nyd8tzPX9R7BWHguqsrbFdRx3WQ/1ib8I44HXV5yTA=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210909193231-528a39cd75f3 h1:3Ad41xy2WCESpufXwgs7NpDSu+vjxqLt2UFqUV+20bI=
 golang.org/x/sys v0.0.0-20210909193231-528a39cd75f3/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

tool/errorgroup.go

+// Package errgroup provides synchronization, error propagation, and Context
+// cancelation for groups of goroutines working on subtasks of a common task.
+// Based on golangorg/x/sync
+package tool
+
+import (
+	"context"
+	"sync"
+
+	multierror "github.com/hashicorp/go-multierror"
+)
+
+// A Group is a collection of goroutines working on subtasks that are part of
+// the same overall task.
+//
+// A zero Group is valid and does not cancel on error.
+type Group struct {
+	cancel func()
+
+	wg sync.WaitGroup
+
+	errOnce sync.Once
+	errs    error // appended with each error
+	errLock sync.RWMutex
+}
+
+// WithContext returns a new Group and an associated Context derived from ctx.
+//
+// The derived Context is canceled the first time a function passed to Go
+// returns a non-nil error or the first time Wait returns, whichever occurs
+// first.
+func WithContext(ctx context.Context) (*Group, context.Context) {
+	ctx, cancel := context.WithCancel(ctx)
+	return &Group{cancel: cancel}, ctx
+}
+
+// Wait blocks until all function calls from the Go method have returned, then
+// returns an error representing all errors encountered from any goroutines in the group.
+func (g *Group) Wait() error {
+	g.wg.Wait()
+	if g.cancel != nil {
+		g.cancel()
+	}
+	g.errLock.RLock()
+	err := g.errs
+	g.errLock.RUnlock()
+	return err
+}
+
+// Go calls the given function in a new goroutine.
+//
+// The first call to return a non-nil error cancels the group; its error will be
+// returned by Wait.
+func (g *Group) Go(f func() error) {
+	g.wg.Add(1)
+
+	go func() {
+		defer g.wg.Done()
+
+		if err := f(); err != nil {
+			g.errLock.Lock()
+			g.errs = multierror.Append(g.errs, err)
+			g.errLock.Unlock()
+			g.errOnce.Do(func() {
+				if g.cancel != nil {
+					g.cancel()
+				}
+			})
+		}
+	}()
+}

tool/tool.go

 package tool
 
-import "os"
+import (
+	"os"
+
+	"github.com/gookit/goutil/fsutil"
+	"github.com/huandu/xstrings"
+	"github.com/spf13/cast"
+	funk "github.com/thoas/go-funk"
+)
+
+var (
+	ErrorCheck = Asset
+	IsDir      = fsutil.IsDir
+	PWD        = os.Getwd
+	TempDir    = os.TempDir
+	ToString   = cast.ToString
+	Map        = funk.Map
+	Reverse    = xstrings.Reverse
+	WordCount  = xstrings.WordCount
+)
 
 func Asset(err error) {
 	if err != nil {