[lvm-devel] master - libdm: report: implement DM_REPORT_GROUP_JSON for JSON report output
Peter Rajnoha
prajnoha at fedoraproject.org
Mon Jun 20 09:40:16 UTC 2016
Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=094fce37765964a9c3b32d1473e75c7d121eace1
Commit: 094fce37765964a9c3b32d1473e75c7d121eace1
Parent: 230b7ff0f6c844bde2185baa9db63961baefb3d0
Author: Peter Rajnoha <prajnoha at redhat.com>
AuthorDate: Mon May 2 14:21:40 2016 +0200
Committer: Peter Rajnoha <prajnoha at redhat.com>
CommitterDate: Mon Jun 20 10:42:26 2016 +0200
libdm: report: implement DM_REPORT_GROUP_JSON for JSON report output
This patch introduces DM_REPORT_GROUP_JSON report group type. When using
this group type and when pushing a report to such a group, these flags
are automatically unset:
DM_REPORT_OUTPUT_ALIGNED
DM_REPORT_OUTPUT_HEADINGS
DM_REPORT_OUTPUT_COLUMNS_AS_ROWS
...and this flag is set:
DM_REPORT_OUTPUT_BUFFERED
The whole group is encapsulated in { } for the outermost JSON object
and then each report is reported on output as array of objects where
each object is the row from report:
{
"report_name1": [
{field1="value", field2="value",...},
{field1="value", field2="value",...}
...
],
"report_name2": [
{field1="value", field2="value",...},
{field1="value", field2="value",...}
...
]
...
}
---
WHATS_NEW_DM | 1 +
libdm/libdevmapper.h | 3 +-
libdm/libdm-report.c | 241 +++++++++++++++++++++++++++++++++++++++++++++++---
3 files changed, 233 insertions(+), 12 deletions(-)
diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index 9e1985a..da36f49 100644
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
Version 1.02.128 -
=================================
+ Introduce DM_REPORT_GROUP_JSON for report group with JSON output format.
Introduce DM_REPORT_GROUP_BASIC for report group with basic report output.
Introduce DM_REPORT_GROUP_SINGLE for report group having single report only.
Add dm_report_group_{create,push,pop,destroy} to support report grouping.
diff --git a/libdm/libdevmapper.h b/libdm/libdevmapper.h
index fbe4322..cad79dd 100644
--- a/libdm/libdevmapper.h
+++ b/libdm/libdevmapper.h
@@ -2710,7 +2710,8 @@ struct dm_report_group;
typedef enum {
DM_REPORT_GROUP_SINGLE,
- DM_REPORT_GROUP_BASIC
+ DM_REPORT_GROUP_BASIC,
+ DM_REPORT_GROUP_JSON
} dm_report_group_type_t;
struct dm_report_group *dm_report_group_create(dm_report_group_type_t type, void *data);
diff --git a/libdm/libdm-report.c b/libdm/libdm-report.c
index d73598f..485bbdf 100644
--- a/libdm/libdm-report.c
+++ b/libdm/libdm-report.c
@@ -4203,6 +4203,16 @@ static int _sort_rows(struct dm_report *rh)
#define STANDARD_QUOTE "\'"
#define STANDARD_PAIR "="
+#define JSON_INDENT_UNIT 4
+#define JSON_SPACE " "
+#define JSON_QUOTE "\""
+#define JSON_PAIR ":"
+#define JSON_SEPARATOR ","
+#define JSON_OBJECT_START "{"
+#define JSON_OBJECT_END "}"
+#define JSON_ARRAY_START "["
+#define JSON_ARRAY_END "]"
+
#define UNABLE_TO_EXTEND_OUTPUT_LINE_MSG "dm_report: Unable to extend output line"
static int _is_basic_report(struct dm_report *rh)
@@ -4211,6 +4221,12 @@ static int _is_basic_report(struct dm_report *rh)
(rh->group_item->group->type == DM_REPORT_GROUP_BASIC);
}
+static int _is_json_report(struct dm_report *rh)
+{
+ return rh->group_item &&
+ (rh->group_item->group->type == DM_REPORT_GROUP_JSON);
+}
+
/*
* Produce report output
*/
@@ -4225,7 +4241,16 @@ static int _output_field(struct dm_report *rh, struct dm_report_field *field)
char *buf = NULL;
size_t buf_size = 0;
- if (rh->flags & DM_REPORT_OUTPUT_FIELD_NAME_PREFIX) {
+ if (_is_json_report(rh)) {
+ if (!dm_pool_grow_object(rh->mem, JSON_QUOTE, 1) ||
+ !dm_pool_grow_object(rh->mem, fields[field->props->field_num].id, 0) ||
+ !dm_pool_grow_object(rh->mem, JSON_QUOTE, 1) ||
+ !dm_pool_grow_object(rh->mem, JSON_PAIR, 1) ||
+ !dm_pool_grow_object(rh->mem, JSON_QUOTE, 1)) {
+ log_error("dm_report: Unable to extend output line");
+ return 0;
+ }
+ } else if (rh->flags & DM_REPORT_OUTPUT_FIELD_NAME_PREFIX) {
if (!(field_id = dm_strdup(fields[field->props->field_num].id))) {
log_error("dm_report: Failed to copy field name");
return 0;
@@ -4300,12 +4325,19 @@ static int _output_field(struct dm_report *rh, struct dm_report_field *field)
}
}
- if ((rh->flags & DM_REPORT_OUTPUT_FIELD_NAME_PREFIX) &&
- !(rh->flags & DM_REPORT_OUTPUT_FIELD_UNQUOTED))
- if (!dm_pool_grow_object(rh->mem, STANDARD_QUOTE, 1)) {
+ if (rh->flags & DM_REPORT_OUTPUT_FIELD_NAME_PREFIX) {
+ if (!(rh->flags & DM_REPORT_OUTPUT_FIELD_UNQUOTED)) {
+ if (!dm_pool_grow_object(rh->mem, STANDARD_QUOTE, 1)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ }
+ } else if (_is_json_report(rh)) {
+ if (!dm_pool_grow_object(rh->mem, JSON_QUOTE, 1)) {
log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
goto bad;
}
+ }
dm_free(buf);
return 1;
@@ -4407,39 +4439,78 @@ static int _output_as_columns(struct dm_report *rh)
struct dm_list *fh, *rowh, *ftmp, *rtmp;
struct row *row = NULL;
struct dm_report_field *field;
+ struct dm_list *last_row;
+ int do_field_delim;
+ char *line;
/* If headings not printed yet, calculate field widths and print them */
if (!(rh->flags & RH_HEADINGS_PRINTED))
_report_headings(rh);
/* Print and clear buffer */
+ last_row = dm_list_last(&rh->rows);
dm_list_iterate_safe(rowh, rtmp, &rh->rows) {
if (!dm_pool_begin_object(rh->mem, 512)) {
log_error("dm_report: Unable to allocate output line");
return 0;
}
+
+ if (_is_json_report(rh)) {
+ if (!dm_pool_grow_object(rh->mem, JSON_OBJECT_START, 0)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ }
+
row = dm_list_item(rowh, struct row);
+ do_field_delim = 0;
+
dm_list_iterate_safe(fh, ftmp, &row->fields) {
field = dm_list_item(fh, struct dm_report_field);
if (field->props->flags & FLD_HIDDEN)
continue;
+ if (do_field_delim) {
+ if (_is_json_report(rh)) {
+ if (!dm_pool_grow_object(rh->mem, JSON_SEPARATOR, 0) ||
+ !dm_pool_grow_object(rh->mem, JSON_SPACE, 0)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ } else {
+ if (!dm_pool_grow_object(rh->mem, rh->separator, 0)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ }
+ } else
+ do_field_delim = 1;
+
if (!_output_field(rh, field))
goto bad;
- if (!dm_list_end(&row->fields, fh))
- if (!dm_pool_grow_object(rh->mem, rh->separator, 0)) {
- log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
- goto bad;
- }
-
dm_list_del(&field->list);
}
+
+ if (_is_json_report(rh)) {
+ if (!dm_pool_grow_object(rh->mem, JSON_OBJECT_END, 0)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ if (rowh != last_row &&
+ !dm_pool_grow_object(rh->mem, JSON_SEPARATOR, 0)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+ }
+
if (!dm_pool_grow_object(rh->mem, "\0", 1)) {
log_error("dm_report: Unable to terminate output line");
goto bad;
}
- log_print("%s", (char *) dm_pool_end_object(rh->mem));
+
+ line = (char *) dm_pool_end_object(rh->mem);
+ log_print("%*s", rh->group_item ? rh->group_item->group->indent + (int) strlen(line) : 0, line);
dm_list_del(&row->list);
}
@@ -4469,6 +4540,70 @@ static struct report_group_item *_get_topmost_report_group_item(struct dm_report
return item;
}
+static int _json_output_array_start(struct dm_pool *mem, struct report_group_item *item)
+{
+ const char *name = (const char *) item->data;
+ char *output;
+
+ if (!dm_pool_begin_object(mem, 32)) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ return 0;
+ }
+
+ if (!dm_pool_grow_object(mem, JSON_QUOTE, 1) ||
+ !dm_pool_grow_object(mem, name, 0) ||
+ !dm_pool_grow_object(mem, JSON_QUOTE JSON_PAIR JSON_SPACE JSON_ARRAY_START, 0) ||
+ !dm_pool_grow_object(mem, "\0", 1) ||
+ !(output = dm_pool_end_object(mem))) {
+ log_error(UNABLE_TO_EXTEND_OUTPUT_LINE_MSG);
+ goto bad;
+ }
+
+ if (item->parent->store.finished_count > 0)
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_SEPARATOR) - 1, JSON_SEPARATOR);
+
+ if (item->parent->parent && item->parent->data) {
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_OBJECT_START) - 1, JSON_OBJECT_START);
+ item->group->indent += JSON_INDENT_UNIT;
+ }
+
+ log_print("%*s", item->group->indent + (int) strlen(output), output);
+ item->group->indent += JSON_INDENT_UNIT;
+
+ dm_pool_free(mem, output);
+ return 1;
+bad:
+ dm_pool_abandon_object(mem);
+ return 0;
+}
+
+static int _prepare_json_report_output(struct dm_report *rh)
+{
+ if (rh->group_item->output_done && dm_list_empty(&rh->rows))
+ return 1;
+
+ /*
+ * If this report is in JSON group, it must be at the
+ * top of the stack of reports so the output from
+ * different reports do not interleave with each other.
+ */
+ if (_get_topmost_report_group_item(rh->group_item->group) != rh->group_item) {
+ log_error("dm_report: dm_report_output: interleaved reports detected for JSON output");
+ return 0;
+ }
+
+ if (rh->group_item->needs_closing) {
+ log_error("dm_report: dm_report_output: unfinished JSON output detected");
+ return 0;
+ }
+
+ if (!_json_output_array_start(rh->mem, rh->group_item))
+ return_0;
+
+ rh->group_item->needs_closing = 1;
+ return 1;
+}
+
static int _print_basic_report_header(struct dm_report *rh)
{
const char *report_name = (const char *) rh->group_item->data;
@@ -4493,6 +4628,10 @@ int dm_report_output(struct dm_report *rh)
{
int r = 0;
+ if (_is_json_report(rh) &&
+ !_prepare_json_report_output(rh))
+ return_0;
+
if (dm_list_empty(&rh->rows)) {
r = 1;
goto out;
@@ -4524,6 +4663,13 @@ static int _report_group_create_basic(struct dm_report_group *group)
return 1;
}
+static int _report_group_create_json(struct dm_report_group *group)
+{
+ log_print(JSON_OBJECT_START);
+ group->indent += JSON_INDENT_UNIT;
+ return 1;
+}
+
struct dm_report_group *dm_report_group_create(dm_report_group_type_t type, void *data)
{
struct dm_report_group *group;
@@ -4560,6 +4706,10 @@ struct dm_report_group *dm_report_group_create(dm_report_group_type_t type, void
if (!_report_group_create_basic(group))
goto_bad;
break;
+ case DM_REPORT_GROUP_JSON:
+ if (!_report_group_create_json(group))
+ goto_bad;
+ break;
default:
goto_bad;
}
@@ -4597,6 +4747,40 @@ static int _report_group_push_basic(struct report_group_item *item, const char *
return 1;
}
+static int _report_group_push_json(struct report_group_item *item, const char *name)
+{
+ if (name && !(item->data = dm_pool_strdup(item->group->mem, name))) {
+ log_error("dm_report: failed to duplicate json item name");
+ return 0;
+ }
+
+ if (item->report) {
+ item->report->flags &= ~(DM_REPORT_OUTPUT_ALIGNED |
+ DM_REPORT_OUTPUT_HEADINGS |
+ DM_REPORT_OUTPUT_COLUMNS_AS_ROWS);
+ item->report->flags |= DM_REPORT_OUTPUT_BUFFERED;
+ } else {
+ if (name) {
+ if (!_json_output_array_start(item->group->mem, item))
+ return_0;
+ } else {
+ if (!item->parent->parent) {
+ log_error("dm_report: can't use unnamed object at top level of JSON output");
+ return 0;
+ }
+ if (item->parent->store.finished_count > 0)
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_SEPARATOR) - 1, JSON_SEPARATOR);
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_OBJECT_START) - 1, JSON_OBJECT_START);
+ item->group->indent += JSON_INDENT_UNIT;
+ }
+
+ item->output_done = 1;
+ item->needs_closing = 1;
+ }
+
+ return 1;
+}
+
int dm_report_group_push(struct dm_report_group *group, struct dm_report *report, void *data)
{
struct report_group_item *item, *tmp_item;
@@ -4634,6 +4818,10 @@ int dm_report_group_push(struct dm_report_group *group, struct dm_report *report
if (!_report_group_push_basic(item, data))
goto_bad;
break;
+ case DM_REPORT_GROUP_JSON:
+ if (!_report_group_push_json(item, data))
+ goto_bad;
+ break;
default:
goto_bad;
}
@@ -4655,6 +4843,23 @@ static int _report_group_pop_basic(struct report_group_item *item)
return 1;
}
+static int _report_group_pop_json(struct report_group_item *item)
+{
+ if (item->output_done && item->needs_closing) {
+ if (item->data) {
+ item->group->indent -= JSON_INDENT_UNIT;
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_ARRAY_END) - 1, JSON_ARRAY_END);
+ }
+ if (item->parent->data && item->parent->parent) {
+ item->group->indent -= JSON_INDENT_UNIT;
+ log_print("%*s", item->group->indent + (int) sizeof(JSON_OBJECT_END) - 1, JSON_OBJECT_END);
+ }
+ item->needs_closing = 0;
+ }
+
+ return 1;
+}
+
int dm_report_group_pop(struct dm_report_group *group)
{
struct report_group_item *item;
@@ -4676,6 +4881,10 @@ int dm_report_group_pop(struct dm_report_group *group)
if (!_report_group_pop_basic(item))
return_0;
break;
+ case DM_REPORT_GROUP_JSON:
+ if (!_report_group_pop_json(item))
+ return_0;
+ break;
default:
return 0;
}
@@ -4704,6 +4913,12 @@ static int _report_group_destroy_basic(void)
return 1;
}
+static int _report_group_destroy_json(void)
+{
+ log_print(JSON_OBJECT_END);
+ return 1;
+}
+
int dm_report_group_destroy(struct dm_report_group *group)
{
struct report_group_item *item, *tmp_item;
@@ -4728,6 +4943,10 @@ int dm_report_group_destroy(struct dm_report_group *group)
if (!_report_group_destroy_basic())
goto_out;
break;
+ case DM_REPORT_GROUP_JSON:
+ if (!_report_group_destroy_json())
+ goto_out;
+ break;
default:
goto_out;
}
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