Create ngx_mock module and avoid ad-hoc mocking of _G.ngx in specs

.busted

@@ -2,6 +2,7 @@
 
 return {
   _all = {
-    helper = 'spec/spec_helper'
+    helper = 'spec/spec_helper',
+    lpath = './src/?.lua;./spec/support/?.lua;'
   }
 }

spec/ngx-oauth/Cookies_spec.moon

@@ -23,17 +23,13 @@ describe '__call', ->
   setup ->
     _G.pairs = spec_helper.sorted_pairs
     export crypto_stub = mock {
-      encrypt: (bits, key, value) -> "<ENC[#{value}]>"
-      decrypt: (bits, key, value) -> "<DEC[#{value}]>"
+      encrypt: (bits, key, value) -> "~~ENC-#{value}~~"
+      decrypt: (bits, key, value) -> "~~DEC-#{value}~~"
     }
 
   before_each ->
     export cookies = Cookies(conf, crypto_stub)
-    _G.ngx =
-      var: {}
-      header: {}
-      escape_uri: (value) -> value\gsub(' ', '+')
-      unescape_uri: spec_helper.unescape_uri
+    _G.ngx = spec_helper.ngx_mock!
 
 
   describe 'add_token', ->
@@ -69,7 +65,7 @@ describe '__call', ->
       tkn = { access_token: 'acc-token', expires_in: conf.max_age / 2, refresh_token: 'ref-token' }
       expected = {
         access_token_cookie(tkn),
-        "#{prefix}refresh_token=<ENC[#{tkn.refresh_token}]>;max-age=#{conf.max_age};#{cookie_attrs}"
+        "#{prefix}refresh_token=~~ENC-#{tkn.refresh_token}~~;max-age=#{conf.max_age};#{cookie_attrs}"
       }
 
       it 'writes cookie with access token and encrypted refresh token', ->
@@ -114,7 +110,7 @@ describe '__call', ->
       it 'returns decrypted value of the cookie', ->
         set_cookie "#{prefix}refresh_token", 'token-123'
 
-        assert.same '<DEC[token-123]>', cookies.get_refresh_token()
+        assert.same '~~DEC-token-123~~', cookies.get_refresh_token()
         assert.stub(crypto_stub.decrypt).called_with(conf.aes_bits, conf.client_secret, 'token-123')
 
     context 'refresh_token cookie does not exist', ->

spec/ngx-oauth/config_spec.moon

@@ -14,8 +14,7 @@ describe 'load', ->
   }
 
   before_each ->
-    _G.ngx =
-      var: { scheme: 'https', server_name: 'example.org' }
+    _G.ngx.var = { scheme: 'https', server_name: 'example.org' }
 
 
   context 'when all variables are set', ->

spec/ngx-oauth/crypto_spec.moon

@@ -8,10 +8,6 @@ encrypted = 'I6u7/Lp5vS+APJJtBjVRGdteDmq0Fxt45xzrEb7Q9ag='
 
 
 describe 'encrypt/decrypt', ->
-  setup ->
-    _G.ngx = mock
-      encode_base64: (value) -> basexx.to_base64(value)
-      decode_base64: (value) -> basexx.from_base64(value)
 
   it 'encrypts and decryptes string', ->
     encrypted = crypto.encrypt(128, key, plain)
@@ -20,8 +16,6 @@ describe 'encrypt/decrypt', ->
 
 
 describe 'decrypt', ->
-  before_each ->
-    _G.ngx = decode_base64: (value) -> basexx.from_base64(value)
 
   context 'given correct key and encrypted value', ->
     it 'returns decrypted value', ->
@@ -47,5 +41,4 @@ describe 'decrypt', ->
 
   context 'given invalid base64 value', ->
     it 'returns nil', ->
-      _G.ngx.decode_base64 = -> nil
       assert.is_nil crypto.decrypt(128, key, '%invalid%')

spec/ngx-oauth/http_client_spec.moon

@@ -157,12 +157,10 @@ describe 'get_for_json', ->
 describe 'post_form_for_json', ->
 
   headers = { Cookie: 'foo=42;path=/' }
-  body = {foo: 42}
+  body = {colour: '#004b7e'}
   post_form_for_json = -> client.post_form_for_json(headers, url, body)
 
   setup ->
-    _G.ngx = mock
-      encode_args: (tab) -> '<encoded>'
     spy.on(client, 'request')
 
   teardown ->
@@ -188,6 +186,6 @@ describe 'post_form_for_json', ->
   it 'calls request() with body encoded using ngx.encode_args', ->
     post_form_for_json!
     assert.stub(_G.ngx.encode_args).called_with body
-    assert.spy(client.request).called_with(_, _, _, '<encoded>')
+    assert.spy(client.request).called_with(_, _, _, 'colour=%23004b7e')
 
   contexts_json_response -> post_form_for_json!

spec/ngx-oauth/nginx_spec.moon

@@ -6,7 +6,7 @@ nginx = require 'ngx-oauth.nginx'
 
 describe 'add_response_cookies', ->
   before_each ->
-    _G.ngx = { header: {} }
+    _G.ngx = spec_helper.ngx_mock!
 
   set_resp_cookie = (value) ->
     _G.ngx.header['Set-Cookie'] = value
@@ -37,8 +37,8 @@ describe 'add_response_cookies', ->
 
 
 describe 'fail', ->
-  setup ->
-    _G.ngx = mock { ERR: 4, WARN: 5, HTTP_OK: 200, header: {}, log: ->, say: ->, exit: -> }
+  before_each ->
+    _G.ngx = spec_helper.ngx_mock!
 
   context 'given valid status', ->
     before_each -> nginx.fail(503, 'Ay, %s!', 'caramba')
@@ -80,8 +80,6 @@ describe 'fail', ->
 describe 'format_cookie', ->
   setup ->
     _G.pairs = spec_helper.sorted_pairs
-    _G.ngx = mock
-      escape_uri: (value) -> string.gsub(value, ' ', '+')
 
   it 'returns correctly formated cookie with attributes', ->
     actual = nginx.format_cookie('foo', 'meh', version: 1, path: '/')
@@ -100,10 +98,7 @@ describe 'format_cookie', ->
 
 describe 'get_cookie', ->
   setup ->
-    _G.ngx = mock {
-      var: { cookie_plain: 'meh.', cookie_encod: '%2Fping%3F' }
-      unescape_uri: spec_helper.unescape_uri
-    }
+    _G.ngx.var = { cookie_plain: 'meh.', cookie_encod: '%2Fping%3F' }
 
   context 'existing cookie', ->
     it 'returns cookie value from ngx.var', ->
@@ -119,8 +114,6 @@ describe 'get_cookie', ->
 
 
 describe 'log', ->
-  before_each ->
-    _G.ngx = mock { ERR: 4, WARN: 5, INFO: 7, log: -> }
 
   it 'calls ngx.log with given level and message prefixed by [ngx-oauth]', ->
     nginx.log(ngx.WARN, 'allons-y!')

spec/ngx-oauth/oauth2_spec.moon

@@ -16,7 +16,7 @@ http_client_stub = { post_form_for_json: -> }
 
 
 setup ->
-  _G.ngx = { encode_args: spec_helper.encode_args, encode_base64: to_base64 }
+  _G.pairs = spec_helper.sorted_pairs
   -- Trick Lua to require our fake http_client instead of ngx-oauth.http_client module.
   package.loaded['ngx-oauth.http_client'] = http_client_stub
   export oauth = require 'ngx-oauth.oauth2'
@@ -28,7 +28,7 @@ teardown ->
 
 describe 'authorization_url', ->
   expected = 'https://oaas.org/authorize?client_id=client123&redirect_uri='..
-    'http%3A%2F%2Fexample%2Eorg&response_type=code&scope=email&state=xyz'
+    'http%3A%2F%2Fexample.org&response_type=code&scope=email&state=xyz'
 
   it 'returns encoded authorization url with correct query parameters', ->
     actual = oauth.authorization_url(conf, 'xyz')

spec/spec_helper.moon

@@ -1,5 +1,8 @@
 luassert = require 'luassert'
-say = require 'say'
+ngx_mock = require 'ngx_mock'
+say      = require 'say'
+
+_G.ngx = ngx_mock!
 
 -- Assertions
 
@@ -34,21 +37,7 @@ sorted_pairs = (tab) ->
     key, tab[key] if key
 
 
-encode_args = (tab) ->
-  encode_param = (str) ->
-    tostring(str)\gsub('\n', '\r\n')\gsub('([^%w_])', (c) ->
-      string.format('%%%02X', string.byte(c)))
-
-  table.concat([ encode_param(k)..'='..encode_param(v) for k, v in sorted_pairs(tab) ], '&')
-
-
-unescape_uri = (str) ->
-  tostring(str)\gsub('+', ' ')\gsub('\r\n', '\n')\gsub('%%(%x%x)', (h) ->
-    string.char(tonumber(h, 16)))
-
-
 export spec_helper = {
-  :encode_args
   :sorted_pairs
-  :unescape_uri
+  :ngx_mock
 }

spec/support/ngx_mock.lua

@@ -0,0 +1,65 @@
+---------
+-- Mock for global ngx table. This implementation is not complete, it contains
+-- just subset of variables and functions we need.
+
+local basexx = require 'basexx'
+local spy    = require 'luassert.spy'
+local stub   = require 'luassert.stub'
+
+
+local function escape_uri (str)
+  return tostring(str):gsub('\n', '\r\n'):gsub('([^%w%-_.~ ])', function(ch)
+    return string.format('%%%02X', string.byte(ch))
+  end):gsub(' ', '+')
+end
+
+local function encode_args (tab)
+  local list = {}
+  for k, v in pairs(tab) do
+    table.insert(list, escape_uri(k)..'='..escape_uri(v))
+  end
+  return table.concat(list, '&')
+end
+
+local function unescape_uri (str)
+  return tostring(str):gsub('+', ' '):gsub('\r\n', '\n'):gsub('%%(%x%x)', function(b)
+    return string.char(tonumber(b, 16))
+  end)
+end
+
+return function()
+  return {
+    -- Log constants
+    STDERR = 0,
+    EMERG  = 1,
+    ALERT  = 2,
+    CRIT   = 3,
+    ERR    = 4,
+    WARN   = 5,
+    NOTICE = 6,
+    INFO   = 7,
+    DEBUG  = 8,
+
+    -- Tables
+    var = {},
+    header = {},
+
+    -- Spied functions
+
+    -- nginx's implementation returns nil when input can't be decoded.
+    decode_base64 = spy(function(...)
+      local ok, ret = pcall(basexx.from_base64, ...)
+      if ok then return ret end
+    end),
+
+    encode_args   = spy(encode_args),
+    encode_base64 = spy(basexx.to_base64),
+    escape_uri    = spy(escape_uri),
+    unescape_uri  = spy(unescape_uri),
+
+    -- Stubs for functions without any return value
+    log           = stub(),
+    say           = stub(),
+    exit          = stub()
+  }
+end