Merge pull request #39 from Sardtok/print-usage-on-invalid-args

Prints usage when there are unparsed args

Author: macourtney

src/drift/args.clj

@@ -1,10 +1,12 @@
-(ns drift.args)
+(ns drift.args
+  (:require [clojure.string :as string]
+            [drift.config :as config]))
 
 (defn split-args
   "split an arglist using a matcher fn : returns
    [args-before-match, args-including-and-after-match]"
   [args matcher]
-  (split-with #(not (matcher %)) args))
+  (split-with #(not-any? (partial = %) matcher) args))
 
 (defn remove-opt
   "given a matched option and whatever is after it in the arg list, remove the option
@@ -27,22 +29,35 @@
           [{} args]
           specs))
 
+(def config-arg-spec
+  {:key :config
+   :matcher ["-c" "-config" "--config"]
+   :parser symbol
+   :default config/default-config-fn-symbol
+   :desc "Fully qualified name of function returning a Drift configuration map."})
+
 (def migrate-arg-specs
   [{:key :version
-    :matcher #{"-v" "-version" "--version"}}
-   {:key :config
-    :matcher #{"-c" "-config" "--config"}
-    :parser symbol}])
+    :matcher ["-v" "-version" "--version"]
+    :desc "The version number to migrate to. Can be lower than the current version to roll back migrations."}
+   config-arg-spec])
 
 (defn parse-migrate-args
   [args]
   (parse-args args migrate-arg-specs))
 
 (def create-migration-arg-specs
-  [{:key :config
-    :matcher #{"-c" "-config" "--config"}
-    :parser symbol}])
+  [config-arg-spec])
 
 (defn parse-create-migration-args
   [args]
   (parse-args args create-migration-arg-specs))
+
+(defn print-usage
+  #^{:doc "Prints out how to use a command with a given name and specification."}
+  [cmd spec & [required-arg]]
+  (println "Usage: lein" cmd "[options]" (or required-arg ""))
+  (println "Options:")
+  (doseq [arg spec]
+    (println (str " " (string/join " " (:matcher arg)) "\t" (:desc arg)))
+    (when (:default arg) (println "\t\t\tDefault value:" (:default arg)))))

src/drift/execute.clj

@@ -1,5 +1,6 @@
 (ns drift.execute
-  (:require [clojure.tools.logging :as logging]
+  (:require [clojure.string :as string]
+            [clojure.tools.logging :as logging]
             [drift.args :as args]
             [drift.config :as config]
             [drift.core :as core]
@@ -30,6 +31,10 @@
 (defn
   run [args]
   (let [[opts remaining] (args/parse-migrate-args args)]
-    (config/with-config-fn-symbol (:config opts)
-      (fn []
-        (migrate (:version opts) remaining)))))
+    (if (empty? remaining)
+      (config/with-config-fn-symbol
+        (:config opts)
+        (fn []
+          (migrate (:version opts) remaining)))
+      (do (logging/error "Invalid arguments:" (string/join " " remaining))
+          (args/print-usage "migrate" args/migrate-arg-specs)))))

src/drift/generator.clj

@@ -1,8 +1,10 @@
 (ns drift.generator
-  (:require [drift.args :as args]
+  (:require [clojure.string :as string]
+            [clojure.tools.logging :as logging]
+            [drift.args :as args]
             [drift.builder :as builder]
-            [drift.core :as core]
-            [drift.config :as config]))
+            [drift.config :as config]
+            [drift.core :as core]))
 
 (defn
 #^{ :doc "Prints out how to use the generate migration command." }
@@ -13,7 +15,7 @@
 (defn
   create-file-content [migration-namespace ns-content up-content down-content]
   (let [migration-number (core/migration-number-from-namespace migration-namespace)]
-    (str "(ns " migration-namespace (or ns-content (config/default-ns-content))  ")
+    (str "(ns " migration-namespace (or ns-content (config/default-ns-content)) ")
 
 (defn up
   \"Migrates the database up to version " migration-number ".\"
@@ -49,8 +51,11 @@
   "parse command-line args from lein, set up any custom config,
    and invoke generate-migration-file"
   [args]
-  (let [[opts remaining] (args/parse-create-migration-args args)
-        migration-name (first remaining)]
-    (config/with-config-fn-symbol (:config opts)
-      (fn []
-        (generate-migration-file migration-name)))))
+  (let [[opts [migration-name & remaining]] (args/parse-create-migration-args args)]
+    (if (empty? remaining)
+      (config/with-config-fn-symbol
+        (:config opts)
+        (fn []
+          (generate-migration-file migration-name)))
+      (do (logging/error "Invalid arguments:" (string/join " " remaining))
+          (args/print-usage "create-migration" args/create-migration-arg-specs "migration-name")))))