Merge branch 'editscript'

Author: reflechant

README.md

@@ -1,10 +1,16 @@
 # json-diff
 
-A console program to produce colorized **structural diff** of two JSON files
+A console program to produce **structural diff** of two JSON files
 
 ## Usage
 
-    $ java -jar json-diff.jar file1.json file2.json
+    $ java -jar json-diff.jar [-m {visual|patch}] file1.json file2.json
+
+`-m` or `--mode` lets you choose output format.
+
+`visual` prints **all** JSON, marking difference in-place. It's made with [deep-diff2](https://github.com/lambdaisland/deep-diff2).
+
+`patch` prints the minimal necessary changes needed to make file2 from file1. It's made with [editscript](https://github.com/juji-io/editscript).
 
 ## License
 

project.clj

@@ -4,9 +4,11 @@
   :license {:name "EPL-2.0 OR GPL-2.0-or-later WITH Classpath-exception-2.0"
             :url "https://www.eclipse.org/legal/epl-2.0/"}
   :dependencies [[org.clojure/clojure "1.10.1"]
-                 [lambdaisland/deep-diff2 "2.0.108"]
                  [org.clojure/data.json "1.0.0"]
-                 [org.clojure/core.async "1.3.610"]]
+                 [org.clojure/core.async "1.3.610"]
+                 [org.clojure/tools.cli "1.0.194"]
+                 [lambdaisland/deep-diff2 "2.0.108"]
+                 [juji/editscript "0.4.6"]]
   :main ^:skip-aot json-diff.core
   :target-path "target/%s"
   :profiles {:uberjar {:aot :all

src/json_diff/core.clj

@@ -1,32 +1,58 @@
 (ns json-diff.core
-  (:require [clojure.data.json :as json]
-            [clojure.core.async :refer [>! <!! go chan]]
+  (:require [clojure.string :as str]
+            [clojure.java.io :as io]
+            [clojure.data.json :as json]
+            [clojure.core.async :refer [<!! go]]
+            [clojure.tools.cli :refer [parse-opts]]
             [lambdaisland.deep-diff2 :as ddiff]
-            [clojure.java.io :as io])
+            [editscript.core :refer [diff] :rename {diff compact-diff}])
+
   (:gen-class))
 
+(def cli-options
+  [["-m" "--mode MODE" "operation mode: 'visual' or 'patch'"
+    :default :patch
+    :parse-fn #(keyword %)
+    :validate [#(% #{:visual :patch}) "possible modes are 'visual' or 'patch'"]]])
 
-(defn open-parse
-  "open JSON file and parses it"
+(defn parse-async
+  "opens JSON file and parses it asynchronously, returns channel"
   [file-name]
-  (with-open [f (io/reader file-name)]
-    (json/read f)))
+  (go (with-open [f (io/reader file-name)]
+        (json/read f))))
+
+(defn process
+  [f & files]
+  (->> files
+       (map parse-async)
+       (map <!!)
+       (apply f)))
+
+(defn patch
+  "prints compact patch between two JSON objects"
+  [left right]
+  (println (compact-diff left right {:algo :quick})))
 
 (defn diff
-  "returns diff between JSON files"
-  [file-name1 file-name2]
-  (let [c1 (chan)
-        c2 (chan)]
-    (go (>! c1 (open-parse file-name1)))
-    (go (>! c2 (open-parse file-name2)))
-    (ddiff/diff (<!! c1) (<!! c2))))
+  "prints visual diff between two JSON objects"
+  [left right]
+  (ddiff/pretty-print
+   (ddiff/diff left right)))
+
+(defn print-error-exit
+  "prints error message and exits with error code"
+  [msg code]
+  (println msg)
+  (System/exit code))
 
 (defn -main
-  "Main function"
+  "main function"
   [& args]
-  (if (> 2 (count args))
-    (println "Not enough parameters!")
-    (ddiff/pretty-print
-     (diff
-      (first args)
-      (second args)))))
+  (let [{files :arguments
+         errors :errors
+         {:keys [mode]} :options} (parse-opts args cli-options)]
+    (cond
+      errors (print-error-exit (str/join "\n" errors) 1)
+      (not= 2 (count files)) (print-error-exit "you need to pass two JSON files!" 1)
+      (= :visual mode) (apply process diff files)
+      (= :patch mode) (apply process patch files))))