core: Add a ys::ext for extra / external functions

Author: ingydotnet

core/src/yamlscript/runtime.clj

@@ -27,6 +27,7 @@
    [ys.clj]
    [ys.csv]
    [ys.dwim]
+   [ys.ext]
    [ys.json]
    [ys.std]
    [ys.taptest]
@@ -123,6 +124,8 @@
   (sci/copy-ns babashka.process (sci/create-ns 'process)))
 (def set-namespace
   (sci/copy-ns clojure.set (sci/create-ns 'set)))
+(def ext-namespace
+  (sci/copy-ns ys.ext (sci/create-ns 'ys.ext)))
 (def std-namespace
   (sci/copy-ns ys.std (sci/create-ns 'std)))
 (def str-namespace
@@ -149,6 +152,7 @@
 
    'cli     cli-namespace  'ys.cli     cli-namespace
    'csv     csv-namespace  'ys.csv     csv-namespace
+   'ext     ext-namespace  'ys.ext     ext-namespace  'x ext-namespace
    'fs      fs-namespace   'ys.fs      fs-namespace
    'http    http-namespace 'ys.http    http-namespace
    'io      io-namespace   'ys.io      io-namespace

core/src/ys/ext.clj

@@ -0,0 +1,35 @@
+;; Copyright 2023-2025 Ingy dot Net
+;; This code is licensed under MIT license (See License for details)
+
+(ns ys.ext
+  (:require
+   [clojure.string :as str]
+   [babashka.process :as process]
+   [yamlscript.util :as util]
+   [ys.yaml :as yaml]))
+
+(defn github-raw-url [spec]
+  (let [[owner repo ref & path] (str/split spec #"/")]
+    (format
+      "https://raw.githubusercontent.com/%s/%s/refs/heads/%s/%s"
+      owner repo ref (str/join "/" path))))
+
+(defn yq [data cmd]
+  (let [yaml (yaml/dump data)
+        res (process/sh {:in yaml}
+              "yq" "-e" cmd)
+        {:keys [exit out err]} res]
+    (when (and
+            (not= 0 exit)
+            (not= err "Error: no matches found\n"))
+      (util/die "yq error: " (:err res)))
+
+    (let [data (if (str/blank? out)
+                 nil
+                 (yaml/load-all out))]
+      (if (= 1 (count data))
+        (first data)
+        data))))
+
+(comment
+  )