thr3ads.net - Libguestfs - [Libguestfs] [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed [Mar 2019]

If this information is useful, please help other people find it:
Share via:

Pino Toscano

2019-Mar-28 16:59 UTC

[Libguestfs] [PATCH v2 0/4] OCaml tools: output messages as JSON machine

Enhance the output in machine parseable mode, by outputting all the
messages of OCaml tools as JSON to the machine parseable stream.

Related, although not strictly needed for this (and thus can be split
if requested), is the addition of the fd format for the machine
readable stream.

Changes from v1:
- use Obj.magic to convert int -> Unix.file_descr
- add tests

Pino Toscano (4):
  common/mltools: move the code for machine readable up
  common/mltools: make sure machine readable output is flushed
  common/mltools: allow fd for machine readable output
  OCaml tools: output messages into JSON for machine readable

 .gitignore                                  |   1 +
 common/mltools/Makefile.am                  |  39 ++++++-
 common/mltools/parse_tools_messages_test.py | 118 ++++++++++++++++++++
 common/mltools/test-machine-readable.sh     |   7 ++
 common/mltools/test-tools-messages.sh       |  28 +++++
 common/mltools/tools_messages_tests.ml      |  46 ++++++++
 common/mltools/tools_utils-c.c              |  51 +++++++++
 common/mltools/tools_utils.ml               |  89 ++++++++++-----
 lib/guestfs.pod                             |  24 ++++
 9 files changed, 371 insertions(+), 32 deletions(-)
 create mode 100644 common/mltools/parse_tools_messages_test.py
 create mode 100755 common/mltools/test-tools-messages.sh
 create mode 100644 common/mltools/tools_messages_tests.ml

-- 
2.20.1

Pino Toscano

2019-Mar-28 16:59 UTC

head link

[Libguestfs] [PATCH v2 1/4] common/mltools: move the code for machine readable up

Move the code for handling machine readable up in the file, so it can be
used by other functions.

Only code motion, no behaviour changes.
---
 common/mltools/tools_utils.ml | 60 +++++++++++++++++------------------
 1 file changed, 30 insertions(+), 30 deletions(-)

diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
index 24641369e..5a35708cd 100644
--- a/common/mltools/tools_utils.ml
+++ b/common/mltools/tools_utils.ml
@@ -33,6 +33,36 @@ external c_inspect_decrypt : Guestfs.t -> int64 ->
(string * key_store_key) list
 external c_set_echo_keys : unit -> unit =
"guestfs_int_mllib_set_echo_keys" "noalloc"
 external c_set_keys_from_stdin : unit -> unit =
"guestfs_int_mllib_set_keys_from_stdin" "noalloc"
 
+type machine_readable_fn = {
+  pr : 'a. ('a, unit, string, unit) format4 -> 'a;
+} (* [@@unboxed] *)
+
+type machine_readable_output_type +  | NoOutput
+  | Channel of out_channel
+  | File of string
+let machine_readable_output = ref NoOutput
+let machine_readable_channel = ref None
+let machine_readable () +  let chan +    if !machine_readable_channel = None
then (
+      let chan +        match !machine_readable_output with
+        | NoOutput -> None
+        | Channel chan -> Some chan
+        | File f -> Some (open_out f) in
+      machine_readable_channel := chan
+    );
+    !machine_readable_channel
+  in
+  match chan with
+  | None -> None
+  | Some chan ->
+    let pr fs +      ksprintf (output_string chan) fs
+    in
+    Some { pr }
+
 (* ANSI terminal colours. *)
 let istty chan    Unix.isatty (Unix.descr_of_out_channel chan)
@@ -236,36 +266,6 @@ let human_size i      )
   )
 
-type machine_readable_fn = {
-  pr : 'a. ('a, unit, string, unit) format4 -> 'a;
-} (* [@@unboxed] *)
-
-type machine_readable_output_type -  | NoOutput
-  | Channel of out_channel
-  | File of string
-let machine_readable_output = ref NoOutput
-let machine_readable_channel = ref None
-let machine_readable () -  let chan -    if !machine_readable_channel = None
then (
-      let chan -        match !machine_readable_output with
-        | NoOutput -> None
-        | Channel chan -> Some chan
-        | File f -> Some (open_out f) in
-      machine_readable_channel := chan
-    );
-    !machine_readable_channel
-  in
-  match chan with
-  | None -> None
-  | Some chan ->
-    let pr fs -      ksprintf (output_string chan) fs
-    in
-    Some { pr }
-
 type cmdline_options = {
   getopt : Getopt.t;
   ks : key_store;
-- 
2.20.1

Pino Toscano

2019-Mar-28 16:59 UTC

head link

[Libguestfs] [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed

Enhance the helper printf function for machine readable output to always
flush after each string: this way, readers of the machine readable
stream can get the output as soon as it is outputted.
---
 common/mltools/tools_utils.ml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
index 5a35708cd..ade4cb37f 100644
--- a/common/mltools/tools_utils.ml
+++ b/common/mltools/tools_utils.ml
@@ -59,7 +59,11 @@ let machine_readable ()    | None -> None
   | Some chan ->
     let pr fs -      ksprintf (output_string chan) fs
+      let out s +        output_string chan s;
+        flush chan
+      in
+      ksprintf out fs
     in
     Some { pr }
 
-- 
2.20.1

Pino Toscano

2019-Mar-28 16:59 UTC

head link

[Libguestfs] [PATCH v2 3/4] common/mltools: allow fd for machine readable output

Allow to specify a file descriptor for the machine readable output.

Use the same assumption as done in v2v, i.e. that Unix.file_descr is
simply the int file descriptor.
---
 common/mltools/test-machine-readable.sh |  7 +++++++
 common/mltools/tools_utils.ml           | 11 ++++++++++-
 lib/guestfs.pod                         |  5 +++++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/common/mltools/test-machine-readable.sh
b/common/mltools/test-machine-readable.sh
index 1162c58e9..824460e6d 100755
--- a/common/mltools/test-machine-readable.sh
+++ b/common/mltools/test-machine-readable.sh
@@ -65,3 +65,10 @@ test $($t --machine-readable=stream:stdout |& wc -l) -eq
3
 # Output "stream:stderr".
 $t --machine-readable=stream:stderr 2>&1 >/dev/null | grep
'machine-readable'
 test $($t --machine-readable=stream:stderr 2>&1 >/dev/null | wc -l)
-eq 2
+
+# Output "fd:".
+fn="$tmpdir/fdfile"
+exec 4>"$fn"
+$t --machine-readable=fd:4
+exec 4>&-
+test $(cat "$fn" | wc -l) -eq 1
diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
index ade4cb37f..35478f39e 100644
--- a/common/mltools/tools_utils.ml
+++ b/common/mltools/tools_utils.ml
@@ -41,6 +41,7 @@ type machine_readable_output_type    | NoOutput
   | Channel of out_channel
   | File of string
+  | Fd of int
 let machine_readable_output = ref NoOutput
 let machine_readable_channel = ref None
 let machine_readable () @@ -50,7 +51,10 @@ let machine_readable ()         
match !machine_readable_output with
         | NoOutput -> None
         | Channel chan -> Some chan
-        | File f -> Some (open_out f) in
+        | File f -> Some (open_out f)
+        | Fd fd ->
+          (* Note that Unix.file_descr is really just an int. *)
+          Some (Unix.out_channel_of_descr (Obj.magic fd)) in
       machine_readable_channel := chan
     );
     !machine_readable_channel
@@ -296,6 +300,11 @@ let create_standard_options argspec ?anon_fun ?(key_opts =
false) ?(machine_read
           | n ->
             error (f_"invalid output stream for --machine-readable:
%s") fmt in
         machine_readable_output := Channel chan
+      | "fd" ->
+        (try
+          machine_readable_output := Fd (int_of_string outname)
+        with Failure _ ->
+          error (f_"invalid output fd for --machine-readable: %s")
fmt)
       | n ->
         error (f_"invalid output for --machine-readable: %s") fmt
       )
diff --git a/lib/guestfs.pod b/lib/guestfs.pod
index 53cece2da..f11028466 100644
--- a/lib/guestfs.pod
+++ b/lib/guestfs.pod
@@ -3287,6 +3287,11 @@ The possible values are:
 
 =over 4
 
+=item B<fd:>I<fd>
+
+The output goes to the specified I<fd>, which is a file descriptor
+already opened for writing.
+
 =item B<file:>F<filename>
 
 The output goes to the specified F<filename>.
-- 
2.20.1

Pino Toscano

2019-Mar-28 16:59 UTC

head link

[Libguestfs] [PATCH v2 4/4] OCaml tools: output messages into JSON for machine readable

When the machine readable mode is enabled, print all the messages
(progress, info, warning, and errors) also as JSON in the machine
readable stream: this way, users can easily parse the status of the
OCaml tool, and report that back.

The formatting of the current date time into the RFC 3999 format is done
in C, because of the lack of OCaml APIs for this.
---
 .gitignore                                  |   1 +
 common/mltools/Makefile.am                  |  39 ++++++-
 common/mltools/parse_tools_messages_test.py | 118 ++++++++++++++++++++
 common/mltools/test-tools-messages.sh       |  28 +++++
 common/mltools/tools_messages_tests.ml      |  46 ++++++++
 common/mltools/tools_utils-c.c              |  51 +++++++++
 common/mltools/tools_utils.ml               |  16 +++
 lib/guestfs.pod                             |  19 ++++
 8 files changed, 316 insertions(+), 2 deletions(-)
 create mode 100644 common/mltools/parse_tools_messages_test.py
 create mode 100755 common/mltools/test-tools-messages.sh
 create mode 100644 common/mltools/tools_messages_tests.ml

diff --git a/.gitignore b/.gitignore
index 9a448fc4e..bfe44cd97 100644
--- a/.gitignore
+++ b/.gitignore
@@ -147,6 +147,7 @@ Makefile.in
 /common/mltools/JSON_tests
 /common/mltools/JSON_parser_tests
 /common/mltools/machine_readable_tests
+/common/mltools/tools_messages_tests
 /common/mltools/tools_utils_tests
 /common/mltools/oUnit-*
 /common/mlutils/.depend
diff --git a/common/mltools/Makefile.am b/common/mltools/Makefile.am
index 37d10e610..ae78b84b7 100644
--- a/common/mltools/Makefile.am
+++ b/common/mltools/Makefile.am
@@ -27,6 +27,8 @@ EXTRA_DIST = \
 	machine_readable_tests.ml \
 	test-getopt.sh \
 	test-machine-readable.sh \
+	test-tools-messages.sh \
+	tools_messages_tests.ml \
 	tools_utils_tests.ml
 
 SOURCES_MLI = \
@@ -45,12 +47,12 @@ SOURCES_MLI = \
 
 SOURCES_ML = \
 	getopt.ml \
+	JSON.ml \
 	tools_utils.ml \
 	URI.ml \
 	planner.ml \
 	registry.ml \
 	regedit.ml \
-	JSON.ml \
 	JSON_parser.ml \
 	curl.ml \
 	checksums.ml \
@@ -196,6 +198,15 @@ machine_readable_tests_CPPFLAGS = \
 machine_readable_tests_BOBJECTS = machine_readable_tests.cmo
 machine_readable_tests_XOBJECTS = $(machine_readable_tests_BOBJECTS:.cmo=.cmx)
 
+tools_messages_tests_SOURCES = dummy.c
+tools_messages_tests_CPPFLAGS = \
+	-I. \
+	-I$(top_builddir) \
+	-I$(shell $(OCAMLC) -where) \
+	-I$(top_srcdir)/lib
+tools_messages_tests_BOBJECTS = tools_messages_tests.cmo
+tools_messages_tests_XOBJECTS = $(tools_messages_tests_BOBJECTS:.cmo=.cmx)
+
 # Can't call the following as <test>_OBJECTS because automake gets
confused.
 if !HAVE_OCAMLOPT
 tools_utils_tests_THEOBJECTS = $(tools_utils_tests_BOBJECTS)
@@ -212,6 +223,9 @@ JSON_parser_tests.cmo: OCAMLPACKAGES +=
$(OCAMLPACKAGES_TESTS)
 
 machine_readable_tests_THEOBJECTS = $(machine_readable_tests_BOBJECTS)
 machine_readable_tests.cmo: OCAMLPACKAGES += $(OCAMLPACKAGES_TESTS)
+
+tools_messages_tests_THEOBJECTS = $(tools_messages_tests_tests_BOBJECTS)
+tools_messages_tests.cmo: OCAMLPACKAGES += $(OCAMLPACKAGES_TESTS)
 else
 tools_utils_tests_THEOBJECTS = $(tools_utils_tests_XOBJECTS)
 tools_utils_tests.cmx: OCAMLPACKAGES += $(OCAMLPACKAGES_TESTS)
@@ -227,6 +241,9 @@ JSON_parser_tests.cmx: OCAMLPACKAGES +=
$(OCAMLPACKAGES_TESTS)
 
 machine_readable_tests_THEOBJECTS = $(machine_readable_tests_XOBJECTS)
 machine_readable_tests.cmx: OCAMLPACKAGES += $(OCAMLPACKAGES_TESTS)
+
+tools_messages_tests_THEOBJECTS = $(tools_messages_tests_XOBJECTS)
+tools_messages_tests.cmx: OCAMLPACKAGES += $(OCAMLPACKAGES_TESTS)
 endif
 
 OCAMLLINKFLAGS = \
@@ -302,14 +319,32 @@ machine_readable_tests_LINK = \
 	  $(OCAMLPACKAGES) $(OCAMLPACKAGES_TESTS) \
 	  $(machine_readable_tests_THEOBJECTS) -o $@
 
+tools_messages_tests_DEPENDENCIES = \
+	$(tools_messages_tests_THEOBJECTS) \
+	../mlstdutils/mlstdutils.$(MLARCHIVE) \
+	../mlgettext/mlgettext.$(MLARCHIVE) \
+	../mlpcre/mlpcre.$(MLARCHIVE) \
+	$(MLTOOLS_CMA) \
+	$(top_srcdir)/ocaml-link.sh
+tools_messages_tests_LINK = \
+	$(top_srcdir)/ocaml-link.sh -cclib '-lutils -lgnu' -- \
+	  $(OCAMLFIND) $(BEST) $(OCAMLFLAGS) $(OCAMLLINKFLAGS) \
+	  $(OCAMLPACKAGES) $(OCAMLPACKAGES_TESTS) \
+	  $(tools_messages_tests_THEOBJECTS) -o $@
+
 TESTS_ENVIRONMENT = $(top_builddir)/run --test
 
 TESTS = \
 	test-getopt.sh \
 	test-machine-readable.sh
+if HAVE_PYTHON
+TESTS += \
+	test-tools-messages.sh
+endif
 check_PROGRAMS = \
 	getopt_tests \
-	machine_readable_tests
+	machine_readable_tests \
+	tools_messages_tests
 
 if HAVE_OCAML_PKG_OUNIT
 check_PROGRAMS += JSON_tests JSON_parser_tests tools_utils_tests
diff --git a/common/mltools/parse_tools_messages_test.py
b/common/mltools/parse_tools_messages_test.py
new file mode 100644
index 000000000..9dcd6cae6
--- /dev/null
+++ b/common/mltools/parse_tools_messages_test.py
@@ -0,0 +1,118 @@
+# Copyright (C) 2019 Red Hat Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import datetime
+import json
+import os
+import sys
+import unittest
+
+exe = "tools_messages_tests"
+
+if sys.version_info >= (3, 4):
+    def set_fd_inheritable(fd):
+        os.set_inheritable(fd, True)
+else:
+    def set_fd_inheritable(fd):
+        pass
+
+
+if sys.version_info >= (3, 0):
+    def fdopen(fd, mode):
+        return open(fd, mode)
+
+    def isModuleInstalled(mod):
+        import importlib
+        return bool(importlib.util.find_spec(mod))
+else:
+    def fdopen(fd, mode):
+        return os.fdopen(fd, mode)
+
+    def isModuleInstalled(mod):
+        import imp
+        try:
+            imp.find_module(mod)
+            return True
+        except ImportError:
+            return False
+
+
+def skipUnlessHasModule(mod):
+    if not isModuleInstalled(mod):
+        return unittest.skip("%s not available" % mod)
+    return lambda func: func
+
+
+def iterload(stream):
+    dec = json.JSONDecoder()
+    for line in stream:
+        yield dec.raw_decode(line)
+
+
+def loadJsonFromCommand(extraargs):
+    r, w = os.pipe()
+    set_fd_inheritable(r)
+    r = fdopen(r, "r")
+    set_fd_inheritable(w)
+    w = fdopen(w, "w")
+    pid = os.fork()
+    if pid:
+        w.close()
+        l = list(iterload(r))
+        l = [o[0] for o in l]
+        r.close()
+        return l
+    else:
+        r.close()
+        args = ["tools_messages_tests",
+                "--machine-readable=fd:%d" % w.fileno()] + extraargs
+        os.execvp("./" + exe, args)
+
+
+@skipUnlessHasModule('iso8601')
+class TestParseToolsMessages(unittest.TestCase):
+    def check_json(self, json, typ, msg):
+        import iso8601
+        # Check the type.
+        jsontype = json.pop("type")
+        self.assertEqual(jsontype, typ)
+        # Check the message.
+        jsonmsg = json.pop("message")
+        self.assertEqual(jsonmsg, msg)
+        # Check the timestamp.
+        jsonts = json.pop("timestamp")
+        dt = iso8601.parse_date(jsonts)
+        now = datetime.datetime.now(dt.tzinfo)
+        self.assertGreater(now, dt)
+        # Check there are no more keys left (and thus not previously tested).
+        self.assertEqual(len(json), 0)
+
+    def test_messages(self):
+        objects = loadJsonFromCommand([])
+        self.assertEqual(len(objects), 4)
+        self.check_json(objects[0], "message", "Starting")
+        self.check_json(objects[1], "info", "An information
message")
+        self.check_json(objects[2], "warning", "Warning: message
here")
+        self.check_json(objects[3], "message", "Finishing")
+
+    def test_error(self):
+        objects = loadJsonFromCommand(["--error"])
+        self.assertEqual(len(objects), 1)
+        self.check_json(objects[0], "error", "Error!")
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/common/mltools/test-tools-messages.sh
b/common/mltools/test-tools-messages.sh
new file mode 100755
index 000000000..0e24d6ce9
--- /dev/null
+++ b/common/mltools/test-tools-messages.sh
@@ -0,0 +1,28 @@
+#!/bin/bash -
+# libguestfs
+# Copyright (C) 2019 Red Hat Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+# Test the --machine-readable functionality of the module Tools_utils.
+# See also: machine_readable_tests.ml
+
+set -e
+set -x
+
+$TEST_FUNCTIONS
+skip_if_skipped
+
+$PYTHON parse_tools_messages_test.py
diff --git a/common/mltools/tools_messages_tests.ml
b/common/mltools/tools_messages_tests.ml
new file mode 100644
index 000000000..d5f9be89b
--- /dev/null
+++ b/common/mltools/tools_messages_tests.ml
@@ -0,0 +1,46 @@
+(*
+ * Copyright (C) 2019 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *)
+
+(* Test the message output for tools of the module Tools_utils.
+ * The tests are controlled by the test-tools-messages.sh script.
+ *)
+
+open Printf
+
+open Std_utils
+open Tools_utils
+open Getopt.OptionName
+
+let is_error = ref false
+
+let args = [
+  [ L "error" ], Getopt.Set is_error, "Only print the
error";
+]
+let usage_msg = sprintf "%s: test the message outputs" prog
+
+let opthandle = create_standard_options args ~machine_readable:true usage_msg
+let () +  Getopt.parse opthandle.getopt;
+
+  if !is_error then
+    error "Error!";
+
+  message "Starting";
+  info "An information message";
+  warning "Warning: message here";
+  message "Finishing"
diff --git a/common/mltools/tools_utils-c.c b/common/mltools/tools_utils-c.c
index c88c95082..b015dcace 100644
--- a/common/mltools/tools_utils-c.c
+++ b/common/mltools/tools_utils-c.c
@@ -23,6 +23,8 @@
 #include <unistd.h>
 #include <errno.h>
 #include <error.h>
+#include <time.h>
+#include <string.h>
 
 #include <caml/alloc.h>
 #include <caml/fail.h>
@@ -37,6 +39,7 @@
 extern value guestfs_int_mllib_inspect_decrypt (value gv, value gpv, value
keysv);
 extern value guestfs_int_mllib_set_echo_keys (value unitv);
 extern value guestfs_int_mllib_set_keys_from_stdin (value unitv);
+extern value guestfs_int_mllib_rfc3999_date_time_string (value unitv);
 
 /* Interface with the guestfish inspection and decryption code. */
 int echo_keys = 0;
@@ -103,3 +106,51 @@ guestfs_int_mllib_set_keys_from_stdin (value unitv)
   keys_from_stdin = 1;
   return Val_unit;
 }
+
+value
+guestfs_int_mllib_rfc3999_date_time_string (value unitv)
+{
+  CAMLparam1 (unitv);
+  char buf[64];
+  struct timespec ts;
+  struct tm tm;
+  size_t ret;
+  size_t total = 0;
+
+  if (clock_gettime (CLOCK_REALTIME, &ts) == -1)
+    unix_error (errno, (char *) "clock_gettime", Val_unit);
+
+  if (localtime_r (&ts.tv_sec, &tm) == NULL)
+    unix_error (errno, (char *) "localtime_r", caml_copy_int64
(ts.tv_sec));
+
+  /* Sadly strftime does not support nanoseconds, so what we do is:
+   * - stringify everything before the nanoseconds
+   * - print the nanoseconds
+   * - stringify the rest (i.e. the timezone)
+   * then place ':' between the hours, and the minutes of the
+   * timezone offset.
+   */
+
+  ret = strftime (buf, sizeof (buf), "%Y-%m-%dT%H:%M:%S.", &tm);
+  if (ret == 0)
+    unix_error (errno, (char *) "strftime", Val_unit);
+  total += ret;
+
+  ret = snprintf (buf + total, sizeof (buf) - total, "%09ld",
ts.tv_nsec);
+  if (ret == 0)
+    unix_error (errno, (char *) "sprintf", caml_copy_int64
(ts.tv_nsec));
+  total += ret;
+
+  ret = strftime (buf + total, sizeof (buf) - total, "%z", &tm);
+  if (ret == 0)
+    unix_error (errno, (char *) "strftime", Val_unit);
+  total += ret;
+
+  /* Move the timezone minutes one character to the right, moving the
+   * null character too.
+   */
+  memmove (buf + total - 1, buf + total - 2, 3);
+  buf[total - 2] = ':';
+
+  CAMLreturn (caml_copy_string (buf));
+}
diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
index 35478f39e..de42df600 100644
--- a/common/mltools/tools_utils.ml
+++ b/common/mltools/tools_utils.ml
@@ -32,6 +32,7 @@ and key_store_key  external c_inspect_decrypt : Guestfs.t
-> int64 -> (string * key_store_key) list -> unit =
"guestfs_int_mllib_inspect_decrypt"
 external c_set_echo_keys : unit -> unit =
"guestfs_int_mllib_set_echo_keys" "noalloc"
 external c_set_keys_from_stdin : unit -> unit =
"guestfs_int_mllib_set_keys_from_stdin" "noalloc"
+external c_rfc3999_date_time_string : unit -> string =
"guestfs_int_mllib_rfc3999_date_time_string"
 
 type machine_readable_fn = {
   pr : 'a. ('a, unit, string, unit) format4 -> 'a;
@@ -86,12 +87,24 @@ let ansi_magenta ?(chan = stdout) ()  let ansi_restore
?(chan = stdout) ()    if colours () || istty chan then output_string chan
"\x1b[0m"
 
+let log_as_json msgtype msg +  match machine_readable () with
+  | None -> ()
+  | Some { pr } ->
+    let json = [
+      "message", JSON.String msg;
+      "timestamp", JSON.String (c_rfc3999_date_time_string ());
+      "type", JSON.String msgtype;
+    ] in
+    pr "%s\n" (JSON.string_of_doc ~fmt:JSON.Compact json)
+
 (* Timestamped progress messages, used for ordinary messages when not
  * --quiet.
  *)
 let start_t = Unix.gettimeofday ()
 let message fs    let display str +    log_as_json "message" str;
     if not (quiet ()) then (
       let t = sprintf "%.1f" (Unix.gettimeofday () -. start_t) in
       printf "[%6s] " t;
@@ -106,6 +119,7 @@ let message fs  (* Error messages etc. *)
 let error ?(exit_code = 1) fs    let display str +    log_as_json
"error" str;
     let chan = stderr in
     ansi_red ~chan ();
     wrap ~chan (sprintf (f_"%s: error: %s") prog str);
@@ -124,6 +138,7 @@ let error ?(exit_code = 1) fs  
 let warning fs    let display str +    log_as_json "warning" str;
     let chan = stdout in
     ansi_blue ~chan ();
     wrap ~chan (sprintf (f_"%s: warning: %s") prog str);
@@ -134,6 +149,7 @@ let warning fs  
 let info fs    let display str +    log_as_json "info" str;
     let chan = stdout in
     ansi_magenta ~chan ();
     wrap ~chan (sprintf (f_"%s: %s") prog str);
diff --git a/lib/guestfs.pod b/lib/guestfs.pod
index f11028466..3c1d635c5 100644
--- a/lib/guestfs.pod
+++ b/lib/guestfs.pod
@@ -3279,6 +3279,25 @@ Some of the tools support a I<--machine-readable>
option, which is
 generally used to make the output more machine friendly, for easier
 parsing for example.  By default, this output goes to stdout.
 
+When using the I<--machine-readable> option, the progress,
+information, warning, and error messages are also printed in JSON
+format for easier log tracking.  Thus, it is highly recommended to
+redirect the machine-readable output to a different stream.  The
+format of these JSON messages is like the following (actually printed
+within a single line, below it is indented for readability):
+
+ {
+   "message": "Finishing off",
+   "timestamp": "2019-03-22T14:46:49.067294446+01:00",
+   "type": "message"
+ }
+
+C<type> can be: C<message> for progress messages, C<info> for
+information messages, C<warning> for warning messages, and C<error>
+for error message.
+C<timestamp> is the L<RFC
3999|https://www.ietf.org/rfc/rfc3339.txt>
+timestamp of the message.
+
 In addition to that, a subset of these tools support an extra string
 passed to the I<--machine-readable> option: this string specifies
 where the machine-readable output will go.
-- 
2.20.1

Richard W.M. Jones

2019-Mar-29 12:49 UTC

head link

Re: [Libguestfs] [PATCH v2 1/4] common/mltools: move the code for machine readable up

On Thu, Mar 28, 2019 at 05:59:28PM +0100, Pino Toscano
wrote:> Move the code for handling machine readable up in the file, so it can be
> used by other functions.
> 
> Only code motion, no behaviour changes.
ACKed before, ACKed again.

Rich.
>  common/mltools/tools_utils.ml | 60 +++++++++++++++++------------------
>  1 file changed, 30 insertions(+), 30 deletions(-)
> 
> diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
> index 24641369e..5a35708cd 100644
> --- a/common/mltools/tools_utils.ml
> +++ b/common/mltools/tools_utils.ml
> @@ -33,6 +33,36 @@ external c_inspect_decrypt : Guestfs.t -> int64 ->
(string * key_store_key) list
>  external c_set_echo_keys : unit -> unit =
"guestfs_int_mllib_set_echo_keys" "noalloc"
>  external c_set_keys_from_stdin : unit -> unit =
"guestfs_int_mllib_set_keys_from_stdin" "noalloc"
>  
> +type machine_readable_fn = {
> +  pr : 'a. ('a, unit, string, unit) format4 -> 'a;
> +} (* [@@unboxed] *)
> +
> +type machine_readable_output_type > +  | NoOutput
> +  | Channel of out_channel
> +  | File of string
> +let machine_readable_output = ref NoOutput
> +let machine_readable_channel = ref None
> +let machine_readable () > +  let chan > +    if
!machine_readable_channel = None then (
> +      let chan > +        match !machine_readable_output with
> +        | NoOutput -> None
> +        | Channel chan -> Some chan
> +        | File f -> Some (open_out f) in
> +      machine_readable_channel := chan
> +    );
> +    !machine_readable_channel
> +  in
> +  match chan with
> +  | None -> None
> +  | Some chan ->
> +    let pr fs > +      ksprintf (output_string chan) fs
> +    in
> +    Some { pr }
> +
>  (* ANSI terminal colours. *)
>  let istty chan >    Unix.isatty (Unix.descr_of_out_channel chan)
> @@ -236,36 +266,6 @@ let human_size i >      )
>    )
>  
> -type machine_readable_fn = {
> -  pr : 'a. ('a, unit, string, unit) format4 -> 'a;
> -} (* [@@unboxed] *)
> -
> -type machine_readable_output_type > -  | NoOutput
> -  | Channel of out_channel
> -  | File of string
> -let machine_readable_output = ref NoOutput
> -let machine_readable_channel = ref None
> -let machine_readable () > -  let chan > -    if
!machine_readable_channel = None then (
> -      let chan > -        match !machine_readable_output with
> -        | NoOutput -> None
> -        | Channel chan -> Some chan
> -        | File f -> Some (open_out f) in
> -      machine_readable_channel := chan
> -    );
> -    !machine_readable_channel
> -  in
> -  match chan with
> -  | None -> None
> -  | Some chan ->
> -    let pr fs > -      ksprintf (output_string chan) fs
> -    in
> -    Some { pr }
> -
>  type cmdline_options = {
>    getopt : Getopt.t;
>    ks : key_store;
> -- 
> 2.20.1
> 
> _______________________________________________
> Libguestfs mailing list
> Libguestfs@redhat.com
> https://www.redhat.com/mailman/listinfo/libguestfs
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org

Richard W.M. Jones

2019-Mar-29 12:49 UTC

head link

Re: [Libguestfs] [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed

On Thu, Mar 28, 2019 at 05:59:29PM +0100, Pino Toscano
wrote:> Enhance the helper printf function for machine readable output to always
> flush after each string: this way, readers of the machine readable
> stream can get the output as soon as it is outputted.
> ---
>  common/mltools/tools_utils.ml | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
> index 5a35708cd..ade4cb37f 100644
> --- a/common/mltools/tools_utils.ml
> +++ b/common/mltools/tools_utils.ml
> @@ -59,7 +59,11 @@ let machine_readable () >    | None -> None
>    | Some chan ->
>      let pr fs > -      ksprintf (output_string chan) fs
> +      let out s > +        output_string chan s;
> +        flush chan
> +      in
> +      ksprintf out fs
>      in
>      Some { pr }
ACK

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW

Richard W.M. Jones

2019-Mar-29 12:50 UTC

head link

Re: [Libguestfs] [PATCH v2 3/4] common/mltools: allow fd for machine readable output

On Thu, Mar 28, 2019 at 05:59:30PM +0100, Pino Toscano
wrote:> Allow to specify a file descriptor for the machine readable output.
> 
> Use the same assumption as done in v2v, i.e. that Unix.file_descr is
> simply the int file descriptor.
> ---
>  common/mltools/test-machine-readable.sh |  7 +++++++
>  common/mltools/tools_utils.ml           | 11 ++++++++++-
>  lib/guestfs.pod                         |  5 +++++
>  3 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/common/mltools/test-machine-readable.sh
b/common/mltools/test-machine-readable.sh
> index 1162c58e9..824460e6d 100755
> --- a/common/mltools/test-machine-readable.sh
> +++ b/common/mltools/test-machine-readable.sh
> @@ -65,3 +65,10 @@ test $($t --machine-readable=stream:stdout |& wc -l)
-eq 3
>  # Output "stream:stderr".
>  $t --machine-readable=stream:stderr 2>&1 >/dev/null | grep
'machine-readable'
>  test $($t --machine-readable=stream:stderr 2>&1 >/dev/null | wc
-l) -eq 2
> +
> +# Output "fd:".
> +fn="$tmpdir/fdfile"
> +exec 4>"$fn"
> +$t --machine-readable=fd:4
> +exec 4>&-
> +test $(cat "$fn" | wc -l) -eq 1
> diff --git a/common/mltools/tools_utils.ml b/common/mltools/tools_utils.ml
> index ade4cb37f..35478f39e 100644
> --- a/common/mltools/tools_utils.ml
> +++ b/common/mltools/tools_utils.ml
> @@ -41,6 +41,7 @@ type machine_readable_output_type >    | NoOutput
>    | Channel of out_channel
>    | File of string
> +  | Fd of int
>  let machine_readable_output = ref NoOutput
>  let machine_readable_channel = ref None
>  let machine_readable () > @@ -50,7 +51,10 @@ let machine_readable ()
>          match !machine_readable_output with
>          | NoOutput -> None
>          | Channel chan -> Some chan
> -        | File f -> Some (open_out f) in
> +        | File f -> Some (open_out f)
> +        | Fd fd ->
> +          (* Note that Unix.file_descr is really just an int. *)
> +          Some (Unix.out_channel_of_descr (Obj.magic fd)) in
>        machine_readable_channel := chan
>      );
>      !machine_readable_channel
> @@ -296,6 +300,11 @@ let create_standard_options argspec ?anon_fun
?(key_opts = false) ?(machine_read
>            | n ->
>              error (f_"invalid output stream for --machine-readable:
%s") fmt in
>          machine_readable_output := Channel chan
> +      | "fd" ->
> +        (try
> +          machine_readable_output := Fd (int_of_string outname)
> +        with Failure _ ->
> +          error (f_"invalid output fd for --machine-readable:
%s") fmt)
>        | n ->
>          error (f_"invalid output for --machine-readable: %s")
fmt
>        )
> diff --git a/lib/guestfs.pod b/lib/guestfs.pod
> index 53cece2da..f11028466 100644
> --- a/lib/guestfs.pod
> +++ b/lib/guestfs.pod
> @@ -3287,6 +3287,11 @@ The possible values are:
>  
>  =over 4
>  
> +=item B<fd:>I<fd>
> +
> +The output goes to the specified I<fd>, which is a file descriptor
> +already opened for writing.
> +
>  =item B<file:>F<filename>
>  
>  The output goes to the specified F<filename>.
Much simpler :-)

ACK

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW

Richard W.M. Jones

2019-Mar-29 12:51 UTC

head link

Re: [Libguestfs] [PATCH v2 4/4] OCaml tools: output messages into JSON for machine readable

Yes this is fine too, so ACK series.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org

Possibly Parallel Threads

Search for more maybe matching threads

Libguestfs - Mar 2019 - [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed

[Libguestfs] [PATCH v2 0/4] OCaml tools: output messages as JSON machine

[Libguestfs] [PATCH v2 1/4] common/mltools: move the code for machine readable up

[Libguestfs] [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed

[Libguestfs] [PATCH v2 3/4] common/mltools: allow fd for machine readable output

[Libguestfs] [PATCH v2 4/4] OCaml tools: output messages into JSON for machine readable

Re: [Libguestfs] [PATCH v2 1/4] common/mltools: move the code for machine readable up

Re: [Libguestfs] [PATCH v2 2/4] common/mltools: make sure machine readable output is flushed

Re: [Libguestfs] [PATCH v2 3/4] common/mltools: allow fd for machine readable output

Re: [Libguestfs] [PATCH v2 4/4] OCaml tools: output messages into JSON for machine readable

Possibly Parallel Threads