Add linters

.gitignore

@@ -6,6 +6,7 @@
 *.so
 *.dylib
 bin
+tools/bin
 
 # Test binary, build with `go test -c`
 *.test

.golangci.yaml

@@ -0,0 +1,213 @@
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This file contains all available configuration options
+# with their documentation
+
+# options for analysis running
+run:
+  # default concurrency is a available CPU number
+  concurrency: 4
+
+  # timeout for analysis, e.g. 30s, 5m, default is 1m
+  timeout: 5m
+
+  # exit code when at least one issue was found, default is 1
+  issues-exit-code: 1
+
+  # include test files or not, default is true
+  tests: true
+
+  # list of build tags, all linters use it. Default is empty list.
+  # build-tags:
+  #   - mytag
+
+  # which dirs to skip: they won't be analyzed;
+  # can use regexp here: generated.*, regexp is applied on full path;
+  # default value is empty list, but next dirs are always skipped independently
+  # from this option's value:
+  #   	vendor$, third_party$, testdata$, examples$, Godeps$, builtin$
+  # skip-dirs:
+  #   - src/external_libs
+  #   - autogenerated_by_my_lib
+
+  # which files to skip: they will be analyzed, but issues from them
+  # won't be reported. Default value is empty list, but there is
+  # no need to include all autogenerated files, we confidently recognize
+  # autogenerated files. If it's not please let us know.
+  # skip-files:
+  #   - ".*\\.my\\.go$"
+  #   - lib/bad.go
+
+  # by default isn't set. If set we pass it to "go list -mod={option}". From "go help modules":
+  # If invoked with -mod=readonly, the go command is disallowed from the implicit
+  # automatic updating of go.mod described above. Instead, it fails when any changes
+  # to go.mod are needed. This setting is most useful to check that go.mod does
+  # not need updates, such as in a continuous integration and testing system.
+  # If invoked with -mod=vendor, the go command assumes that the vendor
+  # directory holds the correct copies of dependencies and ignores
+  # the dependency descriptions in go.mod.
+  # modules-download-mode: readonly|release|vendor
+
+
+# output configuration options
+output:
+  # colored-line-number|line-number|json|tab|checkstyle|code-climate, default is "colored-line-number"
+  format: colored-line-number
+
+  # print lines of code with issue, default is true
+  print-issued-lines: true
+
+  # print linter name in the end of issue text, default is true
+  print-linter-name: true
+
+
+# all available settings of specific linters
+linters-settings:
+
+  errcheck:
+    # report about not checking of errors in type assertions: `a := b.(MyStruct)`;
+    # default is false: such cases aren't reported by default.
+    check-type-assertions: true
+
+    # report about assignment of errors to blank identifier: `num, _ := strconv.Atoi(numStr)`;
+    # default is false: such cases aren't reported by default.
+    check-blank: true
+
+    # path to a file containing a list of functions to exclude from checking
+    # see https://github.com/kisielk/errcheck#excluding-functions for details
+    # exclude: /path/to/file.txt
+
+  goconst:
+    # minimal length of string constant, 3 by default
+    min-len: 4
+    # minimal occurrences count to trigger, 3 by default
+    min-occurrences: 5
+
+  gocritic:
+    # Which checks should be enabled; can't be combined with 'disabled-checks';
+    # See https://go-critic.github.io/overview#checks-overview
+    # To check which checks are enabled run `GL_DEBUG=gocritic golangci-lint run`
+    # By default list of stable checks is used.
+    enabled-checks:
+      - appendAssign
+      - appendCombine
+      - assignOp
+      - captLocal
+      - caseOrder
+      - commentedOutCode
+      - commentedOutImport
+      - defaultCaseOrder
+      - dupArg
+      - dupBranchBody
+      - dupCase
+      - dupSubExpr
+      - elseif
+      - equalFold
+      - flagDeref
+      - ifElseChain
+      - regexpMust
+      - singleCaseSwitch
+      - sloppyLen
+      - switchTrue
+      - typeAssertChain
+      - typeSwitchVar
+      - underef
+      - unlambda
+      - unslice
+
+    # Which checks should be disabled; can't be combined with 'enabled-checks'; default is empty
+    # disabled-checks:
+    #   - regexpMust
+
+    # Enable multiple checks by tags, run `GL_DEBUG=gocritic golangci-lint run` to see all tags and checks.
+    # Empty list by default. See https://github.com/go-critic/go-critic#usage -> section "Tags".
+    # enabled-tags:
+    #   - performance
+
+    settings: # settings passed to gocritic
+      captLocal:
+        paramsOnly: false
+
+  gocyclo:
+    # minimal code complexity to report, 30 by default (but we recommend 10-20)
+    min-complexity: 15
+
+  gofmt:
+    # simplify code: gofmt with `-s` option, true by default
+    simplify: true
+
+  goimports:
+    # put imports beginning with prefix after 3rd-party packages;
+    # it's a comma-separated list of prefixes
+    local-prefixes: opendev.org/airship/airshipctl
+
+  govet:
+    # report about shadowed variables
+    check-shadowing: true
+
+  misspell:
+    # Correct spellings using locale preferences for US or UK.
+    # Default is to use a neutral variety of English.
+    # Setting locale to US will correct the British spelling of 'colour' to 'color'.
+    locale: US
+    # ignore-words:
+    #   - someword
+
+  nakedret:
+    # make an issue if func has more lines of code than this setting and it has naked returns; default is 30
+    max-func-lines: 10
+
+  lll:
+    # max line length, lines longer will be reported. Default is 120.
+    # '\t' is counted as 1 character by default, and can be changed with the tab-width option
+    line-length: 120
+    # tab width in spaces. Default to 1.
+    tab-width: 1
+
+  unparam:
+    # Inspect exported functions, default is false. Set to true if no external program/library imports your code.
+    # XXX: if you enable this setting, unparam will report a lot of false-positives in text editors:
+    # if it's called for subdir of a project it can't find external interfaces. All text editor integrations
+    # with golangci-lint call it on a directory with the changed file.
+    check-exported: false
+
+  unused:
+    # treat code as a program (not a library) and report unused exported identifiers; default is false.
+    # XXX: if you enable this setting, unused will report a lot of false-positives in text editors:
+    # if it's called for subdirectory of a project it can't find funcs usages. All text editor integrations
+    # with golangci-lint call it on a directory with the changed file.
+    check-exported: false
+
+linters:
+  disable-all: true
+  enable:
+    - errcheck             # Errcheck is a program for checking for unchecked errors in go programs. These unchecked errors can be critical bugs in some cases
+    - goconst              # Finds repeated strings that could be replaced by a constant
+    - gocritic             # The most opinionated Go source code linter
+    - gocyclo              # Computes and checks the cyclomatic complexity of functions
+    - gofmt                # Gofmt checks whether code was gofmt-ed. By default this tool runs with -s option to check for code simplification
+    - goimports            # Goimports does everything that gofmt does. Additionally it checks unused imports
+    - gosec                # Inspects source code for security problems
+    - govet                # Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string
+    - ineffassign          # Detects when assignments to existing variables are not used
+    - lll                  # Reports long lines
+    - misspell             # Finds commonly misspelled English words in comments
+    - nakedret             # Finds naked returns in functions greater than a specified function length
+    - prealloc             # Finds slice declarations that could potentially be preallocated
+    - unconvert            # Remove unnecessary type conversions
+    - unparam              # Reports unused function parameters
+    - unused               # Checks Go code for unused constants, variables, functions and types
+    - varcheck             # Finds unused global variables and constants
+    - whitespace           # Tool for detection of leading and trailing whitespace NOTE(howell): This linter does _not_ check for trailing whitespace in multiline strings
+    - golint               # Finds all coding style mistakes
+    - asciicheck           # Simple linter to check that your code does not contain non-ASCII identifiers

Makefile

@@ -4,6 +4,12 @@ IMG ?= controller:latest
 # Produce CRDs that work back to Kubernetes 1.11 (no version conversion)
 CRD_OPTIONS ?= "crd:trivialVersions=true"
 
+TOOLBINDIR          := tools/bin
+
+# linting
+LINTER              := $(TOOLBINDIR)/golangci-lint
+LINTER_CONFIG       := .golangci.yaml
+
 # Get the currently used golang install path (in GOPATH/bin, unless GOBIN is set)
 ifeq (,$(shell go env GOBIN))
 GOBIN=$(shell go env GOPATH)/bin
@@ -78,3 +84,16 @@ CONTROLLER_GEN=$(GOBIN)/controller-gen
 else
 CONTROLLER_GEN=$(shell which controller-gen)
 endif
+
+.PHONY: lint
+lint: $(LINTER)
+	@echo "Performing linting step..."
+	@./tools/whitespace_linter
+	@./$(LINTER) run --config $(LINTER_CONFIG)
+	@echo "Linting completed successfully"
+
+$(LINTER): $(TOOLBINDIR)
+	./tools/install_linter
+
+$(TOOLBINDIR):
+	mkdir -p $(TOOLBINDIR)

tools/install_linter

@@ -0,0 +1,11 @@
+#!/bin/bash
+set -x
+
+tools_bin_dir="${BASH_SOURCE%/*}"
+download_url=https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh
+version=v1.29.0
+
+if ! curl -sfL "$download_url" | sh -s -- -b "$tools_bin_dir/bin" "$version"; then
+  printf "Something went wrong while installing golangci-lint\n" 1>&2
+  exit 1
+fi

tools/whitespace_linter

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+# git 1.9.0+ allows for exclusions in pathspecs via ':!foo' syntax.
+# However, until git 2.13.0 there must be at least one "inclusive" pathspec, hence the './*'
+trailing_whitespace=$(git grep -E -n -- ' +$' -- './*' ':!*.png')
+
+if [[ -n "$trailing_whitespace" ]]; then
+  printf "ERROR: Trailing whitespaces:\n"
+  awk 'BEGIN {FS=":"} {printf " * %s:%s\n", $1, $2}' <<< "$trailing_whitespace"
+  exit 1
+fi