feat: add CouchDB JavaScript context

implement #232

Author: fox1t

package.json

@@ -10,6 +10,7 @@
   "scripts": {
     "commit": "npx git-cz",
     "build": "npm run clean && tsc -p ./tsconfig.json",
+    "build:designs": "tsc -p ./src/db/tsconfig.json",
     "start": "node dist",
     "clean": "rimraf dist",
     "dev:db": "pouchdb-server --config ./db/config.json",

src/db/context.ts

@@ -0,0 +1,93 @@
+/**
+ * Emits a key-value pair for further processing by CouchDB after the map function is done.
+ * @param {string} key - The view key
+ * @param {any} value - The key’s associated value
+ * @returns {void}
+ */
+declare function emit(key: string, value: any): void
+/**
+ * @deprecated since version 2.0
+ * Extracts the next row from a related view result.
+ * @returns {Object} - View result row
+ */
+declare function getRow<T>(): T
+
+/**
+ * A helper function to check if the provided value is an Array.
+ * @param {Object} obj - Any JavaScript value
+ * @returns {boolean}
+ */
+declare function isArray<T>(obj: T): boolean
+
+/**
+ * Log a message to the CouchDB log (at the INFO level).
+ * @param {string} message - Message to be logged
+ * @returns {void}
+ */
+declare function log(message: string): void
+
+/**
+ * @deprecated since version 2.0
+ * Registers callable handler for specified MIME key.
+ * @param {string} key - MIME key previously defined by registerType()
+ * @param {Function} value - MIME type handler
+ * @returns {void}
+ */
+declare function provides(key: string, func: Function): void
+
+/**
+ * @deprecated since version 2.0
+ * Registers list of MIME types by associated key.
+ * @param {string} key - MIME types
+ * @param {string[]} mimes - MMIME types enumeration
+ * @returns {void}
+ */
+declare function registerType(key: string, mimes: string[]): void
+
+/**
+ * @deprecated since version 2.0
+ * Sends a single string chunk in response.
+ * @param {string} chunk - Text chunk
+ * @returns {void}
+ */
+declare function send(chunk: string): void
+
+interface InitResp {
+  code: number
+  json: object
+  body: string
+  base64: string
+  headers: any
+  stop: boolean
+}
+
+/**
+ * @deprecated since version 2.0
+ * Initiates chunked response. As an option, a custom response object may be sent at this point. For list-functions only!
+ * @param {Object} init_resp - InitResp object
+ * @returns {void}
+ */
+// eslint-disable-next-line
+declare function start(init_resp?: InitResp): void
+
+/**
+ * Sum arr’s items.
+ * @param {number[]} arr - Array of numbers
+ * @returns {number}
+ */
+declare function sum(arr: number[]): number
+
+/**
+ * Encodes obj to JSON string. This is an alias for the JSON.stringify method.
+ * @param {any} obj - Array of numbers
+ * @returns {string}
+ */
+declare function toJSON(obj: any): string
+
+/**
+ * Reduce functions take two required arguments of keys and values lists - the result of the related map function - and an optional third value which indicates if rereduce mode is active or not.
+ * Rereduce is used for additional reduce values list, so when it is true there is no information about related keys (first argument is null).
+ * @param {string[] | null} keys - Array of pairs of docid-key for related map function results. Always null if rereduce is running (has true value).
+ * @returns {void}
+ */
+declare type redfun = (keys: [string, string][] | null, values: any[], rereduce?: boolean) => any

src/db/design.ts

@@ -0,0 +1,40 @@
+export interface Design<T> {
+  _id: string
+  _rev?: string
+  language: 'javascript'
+  views?: {
+    [key: string]: {
+      /**
+       * Map functions accept a single document as the argument and (optionally) emit() key/value pairs that are stored in a view.
+       * Since version 1.1.0, map supports CommonJS modules and the require() function.
+       * @param {Object} doc - The document that is being processed
+       * @returns {void}
+       */
+      map?(doc: T): void
+      /**
+       * Reduce functions take two required arguments of keys and values lists - the result of the related map function - and an optional third value which indicates if rereduce mode is active or not.
+       * Rereduce is used for additional reduce values list, so when it is true there is no information about related keys (first argument is null).
+       * @param {string[] | null} keys - Array of pairs of docid-key for related map function results. Always null if rereduce is running (has true value).
+       * @returns {any}
+       */
+      reduce?(keys: [string, string][] | null, values: any[], rereduce?: boolean): any
+    }
+  }
+  shows?: {
+    [key: string]: () => void
+  }
+  lists?: {
+    [key: string]: () => void
+  }
+  updates?: {
+    [key: string]: () => void
+  }
+  filters?: {
+    [key: string]: () => void
+  }
+  validate_doc_update?: {
+    [key: string]: () => void
+  }
+}
+
+export default Design

src/db/tsconfig.json

@@ -0,0 +1,17 @@
+// we need this custom tsconfig.json to handle CouchDB Javascript Context locally to this folder
+{
+  "extends": "../../tsconfig.json",
+  "include": [
+    "."
+  ],
+  "exclude": [
+    "node_modules",
+  ],
+  "compilerOptions": {
+    "typeRoots": [
+      "../../node_modules/@types",
+      "./context.d.ts"
+    ],
+    "outDir": "../../dist/db",
+  }
+}

tsconfig.json

@@ -4,7 +4,8 @@
   ],
   "exclude": [
     "node_modules",
-    "dist"
+    "dist",
+    "src/db"
   ],
   "compilerOptions": {
     "typeRoots": [