Add support for tfsec Terraform linter (#4323)

1 files changed, 87 insertions, 0 deletions

diff --git a/ale_linters/terraform/tfsec.vim b/ale_linters/terraform/tfsec.vim
new file mode 100644
index 00000000..d29cdd13
--- /dev/null
+++ b/ale_linters/terraform/tfsec.vim
@@ -0,0 +1,87 @@
+" Description: tfsec for Terraform files
+"
+" See: https://www.terraform.io/
+"      https://github.com/aquasecurity/tfsec
+
+call ale#Set('terraform_tfsec_options', '')
+call ale#Set('terraform_tfsec_executable', 'tfsec')
+
+let s:separator = has('win32') ? '\' : '/'
+
+function! ale_linters#terraform#tfsec#Handle(buffer, lines) abort
+    let l:output = []
+    let l:json = ale#util#FuzzyJSONDecode(a:lines, {})
+
+    " if there's no warning, 'result' is `null`.
+    if empty(get(l:json, 'results'))
+        return l:output
+    endif
+
+    for l:result in get(l:json, 'results', [])
+        if l:result.severity is# 'LOW'
+            let l:type = 'I'
+        elseif l:result.severity is# 'CRITICAL'
+            let l:type = 'E'
+        else
+            let l:type = 'W'
+        endif
+
+        call add(l:output, {
+        \   'filename': l:result.location.filename,
+        \   'lnum': l:result.location.start_line,
+        \   'end_lnum': l:result.location.end_line,
+        \   'text': l:result.description,
+        \   'code': l:result.long_id,
+        \   'type': l:type,
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+" Construct command arguments to tfsec with `terraform_tfsec_options`.
+function! ale_linters#terraform#tfsec#GetCommand(buffer) abort
+    let l:cmd = '%e'
+
+    let l:config = ale_linters#terraform#tfsec#FindConfig(a:buffer)
+
+    if !empty(l:config)
+        let l:cmd .= ' --config-file ' . l:config
+    endif
+
+    let l:opts = ale#Var(a:buffer, 'terraform_tfsec_options')
+
+    if !empty(l:opts)
+        let l:cmd .= ' ' . l:opts
+    endif
+
+    let l:cmd .= ' --format json'
+
+    return l:cmd
+endfunction
+
+" Find the nearest configuration file of tfsec.
+function! ale_linters#terraform#tfsec#FindConfig(buffer) abort
+    let l:config_dir = ale#path#FindNearestDirectory(a:buffer, '.tfsec')
+
+    if !empty(l:config_dir)
+        " https://aquasecurity.github.io/tfsec/v1.28.0/guides/configuration/config/
+        for l:basename in ['config.yml', 'config.json']
+            let l:config = ale#path#Simplify(join([l:config_dir, l:basename], s:separator))
+
+            if filereadable(l:config)
+                return ale#Escape(l:config)
+            endif
+        endfor
+    endif
+
+    return ''
+endfunction
+
+call ale#linter#Define('terraform', {
+\   'name': 'tfsec',
+\   'executable': {b -> ale#Var(b, 'terraform_tfsec_executable')},
+\   'cwd': '%s:h',
+\   'command': function('ale_linters#terraform#tfsec#GetCommand'),
+\   'callback': 'ale_linters#terraform#tfsec#Handle',
+\})