neil new: Add support for deps-based templates (#51)

neil

@@ -17,18 +17,15 @@
 (ns babashka.neil
   {:no-doc true})
 
-(require '[babashka.classpath :as cp]
-         '[babashka.cli :as cli]
+(require '[babashka.cli :as cli]
          '[babashka.curl :as curl]
          '[babashka.fs :as fs]
          '[borkdude.rewrite-edn :as r]
          '[cheshire.core :as cheshire]
          '[clojure.edn :as edn]
+         '[clojure.set :as set]
          '[clojure.string :as str])
 
-;; deps-new reads classpath from property
-(System/setProperty "java.class.path" (cp/get-classpath))
-
 (def spec {:lib {:desc "Fully qualified library name."}
            :version {:desc "Optional. When not provided, picks newest version from Clojars or Maven Central."}
            :sha {:desc "When provided, assumes lib refers to Github repo."}
@@ -42,15 +39,17 @@
            :deps-file {:ref "<file>"
                        :desc "Add to <file> instead of deps.edn."
                        :default "deps.edn"}
-           :limit {:coerce :long}
-           })
+           :limit {:coerce :long}})
+
 
 (import java.net.URLEncoder)
 
 (def version "0.0.33")
 
 (def windows? (str/includes? (System/getProperty "os.name") "Windows"))
 
+(def bb? (System/getProperty "babashka.version"))
+
 (defn url-encode [s] (URLEncoder/encode s "UTF-8"))
 
 (def curl-opts
@@ -113,11 +112,19 @@
                                 (namespace lib) (name lib) branch))
          :sha)))
 
-(defn latest-github-tag [lib]
+(defn list-github-tags [lib]
   (let [lib (clean-github-lib lib)]
-    (first
-     (curl-get-json (format "https://api.github.com/repos/%s/%s/tags"
-                            (namespace lib) (name lib))))))
+    (curl-get-json (format "https://api.github.com/repos/%s/%s/tags"
+                           (namespace lib) (name lib)))))
+
+(defn latest-github-tag [lib]
+  (-> (list-github-tags lib)
+      first))
+
+(defn find-github-tag [lib tag]
+  (->> (list-github-tags lib)
+       (filter #(= (:name %) tag))
+       first))
 
 (def deps-template
   (str/triml "
@@ -373,36 +380,195 @@
                :version (:version search-result)
                :description (pr-str (:description search-result))))))
 
-(def deps-new-opts
-  [; main opts
-   :template
-   :name
-   :target-dir
-   :overwrite
-
-   ; optional overrides
-   :artifact/id
-   :description
-   :developer
-   :group/id
-   :main
-   :name
-   :now/date
-   :now/year
-   :raw-name
-   :scm/domain
-   :scm/user
-   :scm/repo
-   :top
-   :user
-   :version])
-
-(defn run-deps-new [{:keys [opts]}]
-  (let [{:keys [template]
-         :or {template "scratch"}} opts
-        template-fn (requiring-resolve (symbol "org.corfield.new" template))]
-    (template-fn (dissoc opts :template))
-    nil))
+(defn- built-in-template?
+  "Returns true if the template name maps to a function in org.corfield.new."
+  [template]
+  (contains? (set (map name (keys (ns-publics 'org.corfield.new)))) template))
+
+(defn- github-repo-http-url [lib]
+  (str "https://github.com/" (clean-github-lib lib)))
+
+(def github-repo-ssh-regex #"^[email protected]:([^/]+)/([^\.]+)\.git$")
+(def github-repo-http-regex #"^https://github.com/([^/]+)/([^\.]+)(\.git)?$")
+
+(defn- parse-git-url [git-url]
+  (let [[[_ gh-user repo-name]] (or (re-seq github-repo-ssh-regex git-url)
+                                    (re-seq github-repo-http-regex git-url))]
+    (if (and gh-user repo-name)
+      {:gh-user gh-user :repo-name repo-name}
+      (throw (ex-info "Failed to parse :git/url" {:git/url git-url})))))
+
+(defn- git-url->lib-sym [git-url]
+  (when-let [{:keys [gh-user repo-name]} (parse-git-url git-url)]
+    (symbol (str "io.github." gh-user) repo-name)))
+
+(def lib-opts->template-deps-fn
+  "A map to define valid CLI options for deps-new template deps.
+
+  - Each key is a sequence of valid combinations of CLI opts.
+  - Each value is a function which returns a tools.deps lib map."
+  {[#{:local/root}]
+   (fn [lib-sym lib-opts]
+     {lib-sym (select-keys lib-opts [:local/root])})
+
+   [#{} #{:git/url}]
+   (fn [lib-sym lib-opts]
+     (let [url (or (:git/url lib-opts) (github-repo-http-url lib-sym))
+           {:keys [name commit]} (latest-github-tag (git-url->lib-sym url))]
+       {lib-sym {:git/url url :git/tag name :git/sha (:sha commit)}}))
+
+   [#{:git/tag} #{:git/url :git/tag}]
+   (fn [lib-sym lib-opts]
+     (let [url (or (:git/url lib-opts) (github-repo-http-url lib-sym))
+           tag (:git/tag lib-opts)
+           {:keys [commit]} (find-github-tag (git-url->lib-sym url) tag)]
+       {lib-sym {:git/url url :git/tag tag :git/sha (:sha commit)}}))
+
+   [#{:git/sha} #{:git/url :git/sha}]
+   (fn [lib-sym lib-opts]
+     (let [url (or (:git/url lib-opts) (github-repo-http-url lib-sym))
+           sha (:git/sha lib-opts)]
+       {lib-sym {:git/url url :git/sha sha}}))
+
+   [#{:latest-sha} #{:git/url :latest-sha}]
+   (fn [lib-sym lib-opts]
+     (let [url (or (:git/url lib-opts) (github-repo-http-url lib-sym))
+           sha (latest-github-sha (git-url->lib-sym url))]
+       {lib-sym {:git/url url :git/sha sha}}))
+
+   [#{:git/url :git/tag :git/sha}]
+   (fn [lib-sym lib-opts]
+     {lib-sym (select-keys lib-opts [:git/url :git/tag :git/sha])})})
+
+(def valid-lib-opts
+  "The set of all valid combinations of deps-new template deps opts."
+  (into #{} cat (keys lib-opts->template-deps-fn)))
+
+(defn- deps-new-cli-opts->lib-opts
+  "Returns parsed deps-new template deps opts from raw CLI opts."
+  [cli-opts]
+  (-> cli-opts
+      (set/rename-keys {:sha :git/sha})
+      (select-keys (into #{} cat valid-lib-opts))))
+
+(defn- invalid-lib-opts-error [provided-lib-opts]
+  (ex-info (str "Provided invalid combination of CLI options for deps-new "
+                "template deps.")
+           {:provided-opts (set (keys provided-lib-opts))
+            :valid-combinations valid-lib-opts}))
+
+(defn- find-template-deps-fn
+  "Returns a template-deps-fn given lib-opts parsed from raw CLI opts."
+  [lib-opts]
+  (some (fn [[k v]] (and (contains? (set k) (set (keys lib-opts))) v))
+        lib-opts->template-deps-fn))
+
+(defn- template-deps
+  "Returns a tools.deps lib map for the given CLI opts."
+  [template cli-opts]
+  (let [lib-opts (deps-new-cli-opts->lib-opts cli-opts)
+        lib-sym (edn/read-string template)
+        template-deps-fn (find-template-deps-fn lib-opts)]
+    (if-not template-deps-fn
+      (throw (invalid-lib-opts-error lib-opts))
+      (template-deps-fn lib-sym lib-opts))))
+
+(def create-opts-deny-list
+  [:deps-file :dry-run :git/sha :git/url :latest-sha :local/root :sha])
+
+(defn- deps-new-plan
+  "Returns a plan for calling org.corfield.new/create.
+
+  :template-deps - These deps will be added with babashka.deps/add-deps before
+                   calling the create function.
+
+  :create-opts   - This map contains the options that will be passed to the
+                   create function."
+  [cli-opts]
+  (let [create-opts (merge {:template "scratch"}
+                           (apply dissoc cli-opts create-opts-deny-list))
+        tpl-deps (when (and bb? (not (built-in-template? (:template create-opts))))
+                   (template-deps (:template create-opts) cli-opts))]
+    (merge (when tpl-deps {:template-deps tpl-deps})
+           {:create-opts create-opts})))
+
+(defn- deps-new-create [create-opts]
+  ((requiring-resolve 'org.corfield.new/create) create-opts))
+
+(defn print-new-help []
+  (println (str/trim "
+Usage: neil new [template] [name] [target-dir] [options]
+
+Runs the org.corfield.new/create function from deps-new.
+
+All of the deps-new options can be provided as CLI options:
+
+https://github.com/seancorfield/deps-new/blob/develop/doc/options.md
+
+Both built-in and external templates are supported. Built-in templates use
+unqualified names (e.g. scratch) whereas external templates use fully-qualified
+names (e.g. io.github.kit/kit-clj).
+
+If an external template is provided, the babashka.deps/add-deps function will be
+called automatically before running org.corfield.new/create. The deps for the
+template are inferred automatically from the template name. The following
+options can be used to control the add-deps behavior:
+
+  --local/root
+    Override the :deps map to use the provided :local/root path.
+
+  --git/url
+    Override the :git/url in the :deps map. If no URL is provided, a template
+    name starting with io.github or com.github is expected and the URL will
+    point to GitHub.
+
+  --git/tag
+    Override the :git/tag in the :deps map. If no SHA or tag is provided, the
+    latest tag from the default branch of :git/url will be used.
+
+  --sha
+  --git/sha
+    Override the :git/sha in the :deps map. If no SHA or tag is provided, the
+    latest tag from the default branch of :git/url will be used.
+
+  --latest-sha
+    Override the :git/sha in the :deps map with the latest SHA from the
+    default branch of :git/url.")))
+
+(defn- deps-new-set-classpath
+  "Sets the java.class.path property.
+
+  This is required by org.corfield.new/create. In Clojure it's set by default,
+  but in Babashka it must be set explicitly."
+  []
+  (let [classpath ((requiring-resolve 'babashka.classpath/get-classpath))]
+    (System/setProperty "java.class.path" classpath)))
+
+(defn- deps-new-add-template-deps
+  "Adds template deps at runtime."
+  [template-deps]
+  ((requiring-resolve 'babashka.deps/add-deps) {:deps template-deps}))
+
+(defn run-deps-new
+  "Runs org.corfield.new/create using the provided CLI options.
+
+  To support the dry run feature, side-effects should be described in the plan
+  provided by deps-new-plan. This function's job is to execute side-effects
+  using the plan to provide repeatability."
+  [{:keys [opts]}]
+  (if (:help opts)
+    (print-new-help)
+    (do
+      (require 'org.corfield.new)
+      (let [plan (deps-new-plan opts)
+            {:keys [template-deps create-opts]} plan]
+        (if (:dry-run opts)
+          (do (prn plan) nil)
+          (do
+            (when template-deps (deps-new-add-template-deps template-deps))
+            (when bb? (deps-new-set-classpath))
+            (deps-new-create create-opts)
+            nil))))))
 
 (defn print-help [_]
   (println (str/trim "
@@ -426,14 +592,13 @@ dep
   add: Adds --lib, a fully qualified symbol, to deps.edn :deps.
     Run neil add dep --help to see all options.
 
-new: Create a new project using deps-new
-  Runs one of the template functions in org.corfield.new.
-
-  See the deps-new docs for all available options:
-  https://github.com/seancorfield/deps-new/blob/develop/doc/options.md
+new:
+  Create a project using deps-new
+    Run neil new --help to see all options.
 
   Examples:
     neil new scratch foo --overwrite
+    neil new io.github.rads/neil-new-test-template foo2 --latest-sha
 
 license
   list   Lists commonly-used licenses available to be added to project. Takes an optional search string to filter results.
@@ -503,7 +668,7 @@ license
     {:cmds ["license" "list"] :fn license-search :cmds-opts [:search-term]}
     {:cmds ["license" "search"] :fn license-search :cmds-opts [:search-term]}
     {:cmds ["license" "add"] :fn add-license :cmds-opts [:license]}
-    {:cmds ["new"] :fn run-deps-new :cmds-opts deps-new-opts}
+    {:cmds ["new"] :fn run-deps-new :cmds-opts [:template :name :target-dir]}
     {:cmds ["version"] :fn print-version}
     {:cmds ["help"] :fn print-help}
     {:cmds [] :fn (fn [{:keys [opts] :as m}]