feat: clean rules up with a bit of a visitor pattern

config/rollup.js

@@ -35,7 +35,7 @@ export default {
 		}),
 		commonjs({
 			namedExports: {
-				'node_modules/lodash/lodash.js': ['intersection', 'isNil', 'isString'],
+				'node_modules/lodash/lodash.js': ['cloneDeep', 'intersection', 'isNil', 'isString'],
 				'node_modules/noicejs/out/main-bundle.js': ['BaseError'],
 				'node_modules/js-yaml/index.js': [
 					'DEFAULT_SAFE_SCHEMA',

rules/salty-dog.yml

@@ -22,17 +22,26 @@ rules:
       properties:
         name:
           type: string
+          pattern: "[-a-z0-9]+"
         desc:
           type: string
+          minLength: 8
+          maxLength: 255
         level:
           type: string
+          enum:
+            - debug
+            - info
+            - warn
+            - error
         tags:
           type: array
           items:
             type: string
             pattern: "[-:a-z0-9]+"
         select:
           type: string
+          minLength: 1
         filter:
           type: object
         check:

src/config/index.ts

@@ -1,14 +1,13 @@
-import { readFile } from 'fs';
 import { DEFAULT_SAFE_SCHEMA, safeLoad, Schema } from 'js-yaml';
 import { isNil, isString } from 'lodash';
 import { join } from 'path';
-import { promisify } from 'util';
 
 import { envType } from 'src/config/type/Env';
 import { includeSchema, includeType } from 'src/config/type/Include';
 import { regexpType } from 'src/config/type/Regexp';
 import { streamType } from 'src/config/type/Stream';
 import { NotFoundError } from 'src/error/NotFoundError';
+import { readFileSync } from 'src/source';
 
 export const CONFIG_ENV = 'SALTY_HOME';
 export const CONFIG_SCHEMA = Schema.create([DEFAULT_SAFE_SCHEMA], [
@@ -20,8 +19,6 @@ export const CONFIG_SCHEMA = Schema.create([DEFAULT_SAFE_SCHEMA], [
 
 includeSchema.schema = CONFIG_SCHEMA;
 
-const readFileSync = promisify(readFile);
-
 /**
  * With the given name, generate all potential config paths in their complete, absolute form.
  *

src/index.ts

@@ -3,9 +3,10 @@ import { safeDump, safeLoad } from 'js-yaml';
 import { detailed, Options } from 'yargs-parser';
 
 import { CONFIG_SCHEMA, loadConfig } from 'src/config';
-import { checkRule, loadRules, resolveRules } from 'src/rule';
+import { loadRules, resolveRules } from 'src/rule';
 import { loadSource, writeSource } from 'src/source';
 import { VERSION_INFO } from 'src/version';
+import { VisitorContext } from 'src/visitor/context';
 
 const CONFIG_ARGS_NAME = 'config-name';
 const CONFIG_ARGS_PATH = 'config-path';
@@ -81,27 +82,26 @@ export async function main(argv: Array<string>): Promise<number> {
   const activeRules = await resolveRules(rules, args.argv as any);
 
   // run rules
-  let errors = 0;
+  const ctx = new VisitorContext(logger);
   switch (args.argv.mode) {
     case 'check':
       for (const rule of activeRules) {
-        if (checkRule(rule, data, logger)) {
+        if (rule.visit(ctx, data)) {
           logger.info({ rule }, 'passed rule');
         } else {
           logger.warn({ rule }, 'failed rule');
-          ++errors;
         }
       }
       break;
     default:
-      logger.error({ mode: args.argv.mode }, 'unsupported mode');
-      ++errors;
+      ctx.logger.error({ mode: args.argv.mode }, 'unsupported mode');
+      ctx.errors.push('unsupported mode');
   }
 
-  if (errors > 0) {
-    logger.error({ errors }, 'some rules failed');
+  if (ctx.errors.length > 0) {
+    logger.error({ errors: ctx.errors }, 'some rules failed');
     if (args.argv.count) {
-      return Math.min(errors, 255);
+      return Math.min(ctx.errors.length, 255);
     } else {
       return STATUS_ERROR;
     }

src/rule.ts

@@ -1,16 +1,16 @@
 import * as Ajv from 'ajv';
-import { readFile } from 'fs';
 import { safeLoad } from 'js-yaml';
 import { JSONPath } from 'jsonpath-plus';
-import { intersection, isNil } from 'lodash';
-import { Logger, LogLevel } from 'noicejs';
-import { promisify } from 'util';
+import { cloneDeep, intersection, isNil } from 'lodash';
+import { LogLevel } from 'noicejs';
 
-import { CONFIG_SCHEMA } from './config';
+import { CONFIG_SCHEMA } from 'src/config';
+import { readFileSync } from 'src/source';
 
-const readFileSync = promisify(readFile);
+import { Visitor } from 'src/visitor';
+import { VisitorContext } from 'src/visitor/context';
 
-export interface Rule {
+export interface RuleData {
   // metadata
   desc: string;
   level: LogLevel;
@@ -43,7 +43,7 @@ export async function loadRules(paths: Array<string>): Promise<Array<Rule>> {
       schema: CONFIG_SCHEMA,
     });
 
-    rules.push(...data.rules);
+    rules.push(...data.rules.map((data: any) => new Rule(data)));
   }
 
   return rules;
@@ -83,44 +83,69 @@ export async function resolveRules(rules: Array<Rule>, selector: RuleSelector):
   return Array.from(activeRules);
 }
 
-export function checkRule(rule: Rule, data: any, logger: Logger): boolean {
-  const ajv = new ((Ajv as any).default)()
-  const check = ajv.compile(rule.check);
-  const filter = compileFilter(rule, ajv);
-  const scopes = JSONPath({
-    json: data,
-    path: rule.select,
-  });
-
-  if (isNil(scopes) || scopes.length === 0) {
-    logger.debug('no data selected');
-    return true;
+export class Rule implements RuleData, Visitor {
+  public readonly check: any;
+  public readonly desc: string;
+  public readonly filter?: any;
+  public readonly level: LogLevel;
+  public readonly name: string;
+  public readonly select: string;
+  public readonly tags: string[];
+
+  constructor(data: RuleData) {
+    this.desc = data.desc;
+    this.level = data.level;
+    this.name = data.name;
+    this.select = data.select;
+    this.tags = Array.from(data.tags);
+
+    // copy schema objects
+    this.check = cloneDeep(data.check);
+    if (!isNil(data.filter)) {
+      this.filter = cloneDeep(data.filter);
+    }
   }
 
-  for (const item of scopes) {
-    logger.debug({ item }, 'filtering item');
-    if (filter(item)) {
-      logger.debug({ item }, 'checking item')
-      if (!check(item)) {
-        logger.warn({
-          desc: rule.desc,
-          errors: check.errors,
-          item,
-        }, 'rule failed on item');
-        return false;
+  public async visit(ctx: VisitorContext, node: any): Promise<VisitorContext> {
+    const ajv = new ((Ajv as any).default)()
+    const check = ajv.compile(this.check);
+    const filter = this.compileFilter(ajv);
+    const scopes = JSONPath({
+      json: node,
+      path: this.select,
+    });
+
+    if (isNil(scopes) || scopes.length === 0) {
+      ctx.logger.debug('no data selected');
+      return ctx;
+    }
+
+    for (const item of scopes) {
+      ctx.logger.debug({ item }, 'filtering item');
+      if (filter(item)) {
+        ctx.logger.debug({ item }, 'checking item')
+        if (!check(item)) {
+          ctx.logger.warn({
+            desc: this.desc,
+            errors: check.errors,
+            item,
+          }, 'rule failed on item');
+          ctx.errors.push(...check.errors);
+          return ctx;
+        }
+      } else {
+        ctx.logger.debug({ errors: filter.errors, item }, 'skipping item');
       }
-    } else {
-      logger.debug({ errors: filter.errors, item }, 'skipping item');
     }
-  }
 
-  return true;
-}
+    return ctx;
+  }
 
-export function compileFilter(rule: Rule, ajv: any): any {
-  if (isNil(rule.filter)) {
-    return () => true;
-  } else {
-    return ajv.compile(rule.filter);
+  protected compileFilter(ajv: any): any {
+    if (isNil(this.filter)) {
+      return () => true;
+    } else {
+      return ajv.compile(this.filter);
+    }
   }
 }

src/source.ts

@@ -1,8 +1,8 @@
 import { promisify } from 'util';
 import { readFile, writeFile } from 'fs';
 
-const readFileSync = promisify(readFile);
-const writeFileSync = promisify(writeFile);
+export const readFileSync = promisify(readFile);
+export const writeFileSync = promisify(writeFile);
 
 export async function loadSource(path: string): Promise<string> {
   if (path === '-') {

src/visitor/context.ts

@@ -0,0 +1,13 @@
+import { Logger } from 'noicejs';
+
+export class VisitorContext {
+  public readonly changes: Array<any>;
+  public readonly errors: Array<any>;
+  public readonly logger: Logger;
+
+  constructor(logger: Logger) {
+    this.changes = [];
+    this.errors = [];
+    this.logger = logger;
+  }
+}

src/visitor/index.ts

@@ -0,0 +1,5 @@
+import { VisitorContext } from 'src/visitor/context';
+
+export interface Visitor {
+  visit(ctx: VisitorContext, node: any): Promise<VisitorContext>;
+}