Merge pull request #86 from spacecowboy/default_plain

automatically select output format when terminal is interactive or not

Author: spacecowboy

Makefile

@@ -5,7 +5,7 @@ gitdescribe := $(shell git describe --tags --match [0-9]*)
 lasttag := $(shell git describe --tags --match [0-9]* --abbrev=0)
 
 version ?= $(lasttag)
-versionlabel = $(shell echo ${version} | awk '{ sub("^[0-9]+\.[0-9]+\.[0-9]+-?", "", $$1); print }')
+versionlabel = $(shell echo ${version} | awk '{ sub("^[0-9]+.[0-9]+.[0-9]+-?", "", $$1); print }')
 versionnumber = $(shell echo ${version} | awk '{ sub("-.*$$", "", $$1); print }')
 
 pkgversion ?= 1

cypher-shell/src/main/java/org/neo4j/shell/ShellRunner.java

@@ -12,6 +12,7 @@
 import java.io.IOException;
 
 import static org.fusesource.jansi.internal.CLibrary.STDIN_FILENO;
+import static org.fusesource.jansi.internal.CLibrary.STDOUT_FILENO;
 import static org.fusesource.jansi.internal.CLibrary.isatty;
 import static org.neo4j.shell.system.Utils.isWindows;
 
@@ -74,7 +75,7 @@ static boolean shouldBeInteractive(@Nonnull CliArgs cliArgs) {
      * Checks if STDIN is a TTY. In case TTY checking is not possible (lack of libc), then the check falls back to
      * the built in Java {@link System#console()} which checks if EITHER STDIN or STDOUT has been redirected.
      *
-     * @return true if the shell reading from an interactive terminal, false otherwise (e.g., we are reading from a
+     * @return true if the shell is reading from an interactive terminal, false otherwise (e.g., we are reading from a
      * file).
      */
     static boolean isInputInteractive() {
@@ -91,4 +92,26 @@ static boolean isInputInteractive() {
             return System.console() != null;
         }
     }
+
+    /**
+     * Checks if STDOUT is a TTY. In case TTY checking is not possible (lack of libc), then the check falls back to
+     * the built in Java {@link System#console()} which checks if EITHER STDIN or STDOUT has been redirected.
+     *
+     * @return true if the shell is outputting to an interactive terminal, false otherwise (e.g., we are outputting
+     * to a file)
+     */
+    static boolean isOutputInteractive() {
+        if (isWindows()) {
+            // Input will never be a TTY on windows and it isatty seems to be able to block forever on Windows so avoid
+            // calling it.
+            return System.console() != null;
+        }
+        try {
+            return 1 == isatty(STDOUT_FILENO);
+        } catch (Throwable ignored) {
+            // system is not using libc (like Alpine Linux)
+            // Fallback to checking stdin OR stdout
+            return System.console() != null;
+        }
+    }
 }

cypher-shell/src/main/java/org/neo4j/shell/cli/CliArgHelper.java

@@ -148,10 +148,13 @@ private static ArgumentParser setupParser()
         parser.setDefault("fail-behavior", FAIL_FAST);
 
         parser.addArgument("--format")
-                .help("desired output format, verbose(default) displays statistics, plain only displays data")
+                .help("desired output format, verbose displays results in tabular format and prints statistics, " +
+                        "plain displays data with minimal formatting")
                 .choices(new CollectionArgumentChoice<>(
-                        Format.VERBOSE.name().toLowerCase(), Format.PLAIN.name().toLowerCase()))
-                .setDefault(Format.VERBOSE.name().toLowerCase());
+                        Format.AUTO.name().toLowerCase(),
+                        Format.VERBOSE.name().toLowerCase(),
+                        Format.PLAIN.name().toLowerCase()))
+                .setDefault(Format.AUTO.name().toLowerCase());
 
         parser.addArgument("--debug")
                 .help("print additional debug information")

cypher-shell/src/main/java/org/neo4j/shell/cli/CliArgs.java

@@ -11,7 +11,7 @@ public class CliArgs {
     private String username = "";
     private String password = "";
     private FailBehavior failBehavior = FailBehavior.FAIL_FAST;
-    private Format format = Format.VERBOSE;
+    private Format format = Format.AUTO;
     private Optional<String> cypher = Optional.empty();
     private boolean encryption;
     private boolean debugMode;

cypher-shell/src/main/java/org/neo4j/shell/cli/Format.java

@@ -1,16 +1,25 @@
 package org.neo4j.shell.cli;
 
+import javax.annotation.Nonnull;
+
+import static org.neo4j.shell.ShellRunner.isOutputInteractive;
+
 public enum Format {
+    // Will select depending on if stdout is redirected or not
+    AUTO,
     // Intended for human consumption
     VERBOSE,
     // Intended for machine consumption (nothing except data is printed
     PLAIN;
     // TODO JSON, strictly intended for machine consumption with data formatted in JSON
 
-    public static Format parse(String format) {
+    public static Format parse(@Nonnull String format) {
         if (format.equalsIgnoreCase(PLAIN.name())) {
             return PLAIN;
+        } else if (format.equalsIgnoreCase( VERBOSE.name() )) {
+            return VERBOSE;
+        } else {
+            return isOutputInteractive() ? VERBOSE : PLAIN;
         }
-        return VERBOSE;
     }
 }

cypher-shell/src/test/java/org/neo4j/shell/cli/CliArgsTest.java

@@ -61,10 +61,13 @@ public void setFailBehavior() throws Exception {
     @Test
     public void setFormat() throws Exception {
         // default
-        assertEquals(Format.VERBOSE, cliArgs.getFormat());
+        assertEquals(Format.AUTO, cliArgs.getFormat());
 
         cliArgs.setFormat(Format.PLAIN);
         assertEquals(Format.PLAIN, cliArgs.getFormat());
+
+        cliArgs.setFormat(Format.VERBOSE);
+        assertEquals(Format.VERBOSE, cliArgs.getFormat());
     }
 
     @Test