MEDIUM: stats: Add show json schema
This may be used to output the JSON schema which describes the output of
show info json and show stats json.
The JSON output is without any extra whitespace in order to reduce the
volume of output. For human consumption passing the output through a
pretty printer may be helpful.
e.g.:
$ echo "show schema json" | socat /var/run/haproxy.stat stdio | \
python -m json.tool
The implementation does not generate the schema. Some consideration could
be given to integrating the output of the schema with the output of
typed and json info and stats. In particular the types (u32, s64, etc...)
and tags.
A sample verification of show info json and show stats json using
the schema is as follows. It uses the jsonschema python module:
cat > jschema.py << __EOF__
import json
from jsonschema import validate
from jsonschema.validators import Draft3Validator
with open('schema.txt', 'r') as f:
schema = json.load(f)
Draft3Validator.check_schema(schema)
with open('instance.txt', 'r') as f:
instance = json.load(f)
validate(instance, schema, Draft3Validator)
__EOF__
$ echo "show schema json" | socat /var/run/haproxy.stat stdio > schema.txt
$ echo "show info json" | socat /var/run/haproxy.stat stdio > instance.txt
python ./jschema.py
$ echo "show stats json" | socat /var/run/haproxy.stat stdio > instance.txt
python ./jschema.py
Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/src/stats.c b/src/stats.c
index 66ab8d8..736852b 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -3299,6 +3299,234 @@
return 1;
}
+/* This function dumps the schema onto the stream interface's read buffer.
+ * It returns 0 as long as it does not complete, non-zero upon completion.
+ * No state is used.
+ *
+ * Integer values bouned to the range [-(2**53)+1, (2**53)-1] as
+ * per the recommendation for interoperable integers in section 6 of RFC 7159.
+ */
+static void stats_dump_json_schema(struct chunk *out)
+{
+
+ int old_len = out->len;
+
+ chunk_strcat(out,
+ "{"
+ "\"$schema\":\"http://json-schema.org/draft-04/schema#\","
+ "\"oneOf\":["
+ "{"
+ "\"title\":\"Info\","
+ "\"type\":\"array\","
+ "\"items\":{"
+ "\"properties\":{"
+ "\"title\":\"InfoItem\","
+ "\"type\":\"object\","
+ "\"field\":{\"$ref\":\"#/definitions/field\"},"
+ "\"processNum\":{\"$ref\":\"#/definitions/processNum\"},"
+ "\"tags\":{\"$ref\":\"#/definitions/tags\"},"
+ "\"value\":{\"$ref\":\"#/definitions/typedValue\"}"
+ "},"
+ "\"required\":[\"field\",\"processNum\",\"tags\","
+ "\"value\"]"
+ "}"
+ "},"
+ "{"
+ "\"title\":\"Stat\","
+ "\"type\":\"array\","
+ "\"items\":{"
+ "\"title\":\"InfoItem\","
+ "\"type\":\"object\","
+ "\"properties\":{"
+ "\"objType\":{"
+ "\"enum\":[\"Frontend\",\"Backend\",\"Listener\","
+ "\"Server\",\"Unknown\"]"
+ "},"
+ "\"proxyId\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0"
+ "},"
+ "\"id\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0"
+ "},"
+ "\"field\":{\"$ref\":\"#/definitions/field\"},"
+ "\"processNum\":{\"$ref\":\"#/definitions/processNum\"},"
+ "\"tags\":{\"$ref\":\"#/definitions/tags\"},"
+ "\"typedValue\":{\"$ref\":\"#/definitions/typedValue\"}"
+ "},"
+ "\"required\":[\"objType\",\"proxyId\",\"id\","
+ "\"field\",\"processNum\",\"tags\","
+ "\"value\"]"
+ "}"
+ "},"
+ "{"
+ "\"title\":\"Error\","
+ "\"type\":\"object\","
+ "\"properties\":{"
+ "\"errorStr\":{"
+ "\"type\":\"string\""
+ "},"
+ "\"required\":[\"errorStr\"]"
+ "}"
+ "}"
+ "],"
+ "\"definitions\":{"
+ "\"field\":{"
+ "\"type\":\"object\","
+ "\"pos\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0"
+ "},"
+ "\"name\":{"
+ "\"type\":\"string\""
+ "},"
+ "\"required\":[\"pos\",\"name\"]"
+ "},"
+ "\"processNum\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":1"
+ "},"
+ "\"tags\":{"
+ "\"type\":\"object\","
+ "\"origin\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"Metric\",\"Status\",\"Key\","
+ "\"Config\",\"Product\",\"Unknown\"]"
+ "},"
+ "\"nature\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"Gauge\",\"Limit\",\"Min\",\"Max\","
+ "\"Rate\",\"Counter\",\"Duration\","
+ "\"Age\",\"Time\",\"Name\",\"Output\","
+ "\"Avg\", \"Unknown\"]"
+ "},"
+ "\"scope\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"Cluster\",\"Process\",\"Service\","
+ "\"System\",\"Unknown\"]"
+ "},"
+ "\"required\":[\"origin\",\"nature\",\"scope\"]"
+ "},"
+ "\"typedValue\":{"
+ "\"type\":\"object\","
+ "\"oneOf\":["
+ "{\"$ref\":\"#/definitions/typedValue/definitions/s32Value\"},"
+ "{\"$ref\":\"#/definitions/typedValue/definitions/s64Value\"},"
+ "{\"$ref\":\"#/definitions/typedValue/definitions/u32Value\"},"
+ "{\"$ref\":\"#/definitions/typedValue/definitions/u64Value\"},"
+ "{\"$ref\":\"#/definitions/typedValue/definitions/strValue\"}"
+ "],"
+ "\"definitions\":{"
+ "\"s32Value\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"s32\"]"
+ "},"
+ "\"value\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":-2147483648,"
+ "\"maximum\":2147483647"
+ "}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "},"
+ "\"s64Value\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"s64\"]"
+ "},"
+ "\"value\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":-9007199254740991,"
+ "\"maximum\":9007199254740991"
+ "}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "},"
+ "\"u32Value\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"u32\"]"
+ "},"
+ "\"value\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0,"
+ "\"maximum\":4294967295"
+ "}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "},"
+ "\"u64Value\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"u64\"]"
+ "},"
+ "\"value\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0,"
+ "\"maximum\":9007199254740991"
+ "}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "},"
+ "\"strValue\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"str\"]"
+ "},"
+ "\"value\":{\"type\":\"string\"}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "},"
+ "\"unknownValue\":{"
+ "\"properties\":{"
+ "\"type\":{"
+ "\"type\":\"integer\","
+ "\"minimum\":0"
+ "},"
+ "\"value\":{"
+ "\"type\":\"string\","
+ "\"enum\":[\"unknown\"]"
+ "}"
+ "},"
+ "\"required\":[\"type\",\"value\"]"
+ "}"
+ "}"
+ "}"
+ "}"
+ "}");
+
+ if (old_len == out->len) {
+ chunk_reset(out);
+ chunk_appendf(out,
+ "{\"errorStr\":\"output buffer too short\"}");
+ }
+}
+
+/* This function dumps the schema onto the stream interface's read buffer.
+ * It returns 0 as long as it does not complete, non-zero upon completion.
+ * No state is used.
+ */
+static int stats_dump_json_schema_to_buffer(struct stream_interface *si)
+{
+ chunk_reset(&trash);
+
+ stats_dump_json_schema(&trash);
+
+ if (bi_putchk(si_ic(si), &trash) == -1) {
+ si_applet_cant_put(si);
+ return 0;
+ }
+
+ return 1;
+}
+
static int cli_parse_clear_counters(char **args, struct appctx *appctx, void *private)
{
struct proxy *px;
@@ -3420,11 +3648,17 @@
return stats_dump_stat_to_buffer(appctx->owner, NULL);
}
+static int cli_io_handler_dump_json_schema(struct appctx *appctx)
+{
+ return stats_dump_json_schema_to_buffer(appctx->owner);
+}
+
/* register cli keywords */
static struct cli_kw_list cli_kws = {{ },{
{ { "clear", "counters", NULL }, "clear counters : clear max statistics counters (add 'all' for all counters)", cli_parse_clear_counters, NULL, NULL },
{ { "show", "info", NULL }, "show info : report information about the running process", cli_parse_show_info, cli_io_handler_dump_info, NULL },
{ { "show", "stat", NULL }, "show stat : report counters for each proxy and server", cli_parse_show_stat, cli_io_handler_dump_stat, NULL },
+ { { "show", "schema", "json", NULL }, "show schema json : report schema used for stats", NULL, cli_io_handler_dump_json_schema, NULL },
{{},}
}};