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mirror of https://github.com/postgres/postgres.git synced 2025-07-03 20:02:46 +03:00

Implement jsonpath .datetime() method

This commit implements jsonpath .datetime() method as it's specified in
SQL/JSON standard.  There are no-argument and single-argument versions of
this method.  No-argument version selects first of ISO datetime formats
matching input string.  Single-argument version accepts template string as
its argument.

Additionally to .datetime() method itself this commit also implements
comparison ability of resulting date and time values.  There is some difficulty
because exising jsonb_path_*() functions are immutable, while comparison of
timezoned and non-timezoned types involves current timezone.  At first, current
timezone could be changes in session.  Moreover, timezones themselves are not
immutable and could be updated.  This is why we let existing immutable functions
throw errors on such non-immutable comparison.  In the same time this commit
provides jsonb_path_*_tz() functions which are stable and support operations
involving timezones.  As new functions are added to the system catalog,
catversion is bumped.

Support of .datetime() method was the only blocker prevents T832 from being
marked as supported.  sql_features.txt is updated correspondingly.

Extracted from original patch by Nikita Glukhov, Teodor Sigaev, Oleg Bartunov.
Heavily revised by me.  Comments were adjusted by Liudmila Mantrova.

Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Discussion: https://postgr.es/m/CAPpHfdsZgYEra_PeCLGNoXOWYx6iU-S3wF8aX0ObQUcZU%2B4XTw%40mail.gmail.com
Author: Alexander Korotkov, Nikita Glukhov, Teodor Sigaev, Oleg Bartunov, Liudmila Mantrova
Reviewed-by: Anastasia Lubennikova, Peter Eisentraut
This commit is contained in:
Alexander Korotkov
2019-09-25 21:54:14 +03:00
parent 6dda292d4d
commit bffe1bd684
15 changed files with 1355 additions and 45 deletions

View File

@ -66,6 +66,7 @@
#include "miscadmin.h"
#include "regex/regex.h"
#include "utils/builtins.h"
#include "utils/datetime.h"
#include "utils/datum.h"
#include "utils/formatting.h"
#include "utils/float.h"
@ -107,6 +108,7 @@ typedef struct JsonPathExecContext
* ignored */
bool throwErrors; /* with "false" all suppressible errors are
* suppressed */
bool useTz;
} JsonPathExecContext;
/* Context for LIKE_REGEX execution. */
@ -173,7 +175,8 @@ typedef JsonPathBool (*JsonPathPredicateCallback) (JsonPathItem *jsp,
typedef Numeric (*BinaryArithmFunc) (Numeric num1, Numeric num2, bool *error);
static JsonPathExecResult executeJsonPath(JsonPath *path, Jsonb *vars,
Jsonb *json, bool throwErrors, JsonValueList *result);
Jsonb *json, bool throwErrors,
JsonValueList *result, bool useTz);
static JsonPathExecResult executeItem(JsonPathExecContext *cxt,
JsonPathItem *jsp, JsonbValue *jb, JsonValueList *found);
static JsonPathExecResult executeItemOptUnwrapTarget(JsonPathExecContext *cxt,
@ -214,6 +217,8 @@ static JsonPathBool executeLikeRegex(JsonPathItem *jsp, JsonbValue *str,
static JsonPathExecResult executeNumericItemMethod(JsonPathExecContext *cxt,
JsonPathItem *jsp, JsonbValue *jb, bool unwrap, PGFunction func,
JsonValueList *found);
static JsonPathExecResult executeDateTimeMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
JsonbValue *jb, JsonValueList *found);
static JsonPathExecResult executeKeyValueMethod(JsonPathExecContext *cxt,
JsonPathItem *jsp, JsonbValue *jb, JsonValueList *found);
static JsonPathExecResult appendBoolResult(JsonPathExecContext *cxt,
@ -225,7 +230,8 @@ static void getJsonPathVariable(JsonPathExecContext *cxt,
static int JsonbArraySize(JsonbValue *jb);
static JsonPathBool executeComparison(JsonPathItem *cmp, JsonbValue *lv,
JsonbValue *rv, void *p);
static JsonPathBool compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2);
static JsonPathBool compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2,
bool useTz);
static int compareNumeric(Numeric a, Numeric b);
static JsonbValue *copyJsonbValue(JsonbValue *src);
static JsonPathExecResult getArrayIndex(JsonPathExecContext *cxt,
@ -246,6 +252,8 @@ static JsonbValue *JsonbInitBinary(JsonbValue *jbv, Jsonb *jb);
static int JsonbType(JsonbValue *jb);
static JsonbValue *getScalar(JsonbValue *scalar, enum jbvType type);
static JsonbValue *wrapItemsInArray(const JsonValueList *items);
static int compareDatetime(Datum val1, Oid typid1, Datum val2, Oid typid2,
bool useTz, bool *have_error);
/****************** User interface to JsonPath executor ********************/
@ -261,8 +269,8 @@ static JsonbValue *wrapItemsInArray(const JsonValueList *items);
* SQL/JSON. Regarding jsonb_path_match(), this function doesn't have
* an analogy in SQL/JSON, so we define its behavior on our own.
*/
Datum
jsonb_path_exists(PG_FUNCTION_ARGS)
static Datum
jsonb_path_exists_internal(FunctionCallInfo fcinfo, bool tz)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
JsonPath *jp = PG_GETARG_JSONPATH_P(1);
@ -276,7 +284,7 @@ jsonb_path_exists(PG_FUNCTION_ARGS)
silent = PG_GETARG_BOOL(3);
}
res = executeJsonPath(jp, vars, jb, !silent, NULL);
res = executeJsonPath(jp, vars, jb, !silent, NULL, tz);
PG_FREE_IF_COPY(jb, 0);
PG_FREE_IF_COPY(jp, 1);
@ -287,6 +295,18 @@ jsonb_path_exists(PG_FUNCTION_ARGS)
PG_RETURN_BOOL(res == jperOk);
}
Datum
jsonb_path_exists(PG_FUNCTION_ARGS)
{
return jsonb_path_exists_internal(fcinfo, false);
}
Datum
jsonb_path_exists_tz(PG_FUNCTION_ARGS)
{
return jsonb_path_exists_internal(fcinfo, true);
}
/*
* jsonb_path_exists_opr
* Implementation of operator "jsonb @? jsonpath" (2-argument version of
@ -296,7 +316,7 @@ Datum
jsonb_path_exists_opr(PG_FUNCTION_ARGS)
{
/* just call the other one -- it can handle both cases */
return jsonb_path_exists(fcinfo);
return jsonb_path_exists_internal(fcinfo, false);
}
/*
@ -304,8 +324,8 @@ jsonb_path_exists_opr(PG_FUNCTION_ARGS)
* Returns jsonpath predicate result item for the specified jsonb value.
* See jsonb_path_exists() comment for details regarding error handling.
*/
Datum
jsonb_path_match(PG_FUNCTION_ARGS)
static Datum
jsonb_path_match_internal(FunctionCallInfo fcinfo, bool tz)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
JsonPath *jp = PG_GETARG_JSONPATH_P(1);
@ -319,7 +339,7 @@ jsonb_path_match(PG_FUNCTION_ARGS)
silent = PG_GETARG_BOOL(3);
}
(void) executeJsonPath(jp, vars, jb, !silent, &found);
(void) executeJsonPath(jp, vars, jb, !silent, &found, tz);
PG_FREE_IF_COPY(jb, 0);
PG_FREE_IF_COPY(jp, 1);
@ -343,6 +363,18 @@ jsonb_path_match(PG_FUNCTION_ARGS)
PG_RETURN_NULL();
}
Datum
jsonb_path_match(PG_FUNCTION_ARGS)
{
return jsonb_path_match_internal(fcinfo, false);
}
Datum
jsonb_path_match_tz(PG_FUNCTION_ARGS)
{
return jsonb_path_match_internal(fcinfo, true);
}
/*
* jsonb_path_match_opr
* Implementation of operator "jsonb @@ jsonpath" (2-argument version of
@ -352,7 +384,7 @@ Datum
jsonb_path_match_opr(PG_FUNCTION_ARGS)
{
/* just call the other one -- it can handle both cases */
return jsonb_path_match(fcinfo);
return jsonb_path_match_internal(fcinfo, false);
}
/*
@ -360,8 +392,8 @@ jsonb_path_match_opr(PG_FUNCTION_ARGS)
* Executes jsonpath for given jsonb document and returns result as
* rowset.
*/
Datum
jsonb_path_query(PG_FUNCTION_ARGS)
static Datum
jsonb_path_query_internal(FunctionCallInfo fcinfo, bool tz)
{
FuncCallContext *funcctx;
List *found;
@ -385,7 +417,7 @@ jsonb_path_query(PG_FUNCTION_ARGS)
vars = PG_GETARG_JSONB_P_COPY(2);
silent = PG_GETARG_BOOL(3);
(void) executeJsonPath(jp, vars, jb, !silent, &found);
(void) executeJsonPath(jp, vars, jb, !silent, &found, tz);
funcctx->user_fctx = JsonValueListGetList(&found);
@ -406,13 +438,25 @@ jsonb_path_query(PG_FUNCTION_ARGS)
SRF_RETURN_NEXT(funcctx, JsonbPGetDatum(JsonbValueToJsonb(v)));
}
Datum
jsonb_path_query(PG_FUNCTION_ARGS)
{
return jsonb_path_query_internal(fcinfo, false);
}
Datum
jsonb_path_query_tz(PG_FUNCTION_ARGS)
{
return jsonb_path_query_internal(fcinfo, true);
}
/*
* jsonb_path_query_array
* Executes jsonpath for given jsonb document and returns result as
* jsonb array.
*/
Datum
jsonb_path_query_array(PG_FUNCTION_ARGS)
static Datum
jsonb_path_query_array_internal(FunctionCallInfo fcinfo, bool tz)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
JsonPath *jp = PG_GETARG_JSONPATH_P(1);
@ -420,18 +464,30 @@ jsonb_path_query_array(PG_FUNCTION_ARGS)
Jsonb *vars = PG_GETARG_JSONB_P(2);
bool silent = PG_GETARG_BOOL(3);
(void) executeJsonPath(jp, vars, jb, !silent, &found);
(void) executeJsonPath(jp, vars, jb, !silent, &found, tz);
PG_RETURN_JSONB_P(JsonbValueToJsonb(wrapItemsInArray(&found)));
}
Datum
jsonb_path_query_array(PG_FUNCTION_ARGS)
{
return jsonb_path_query_array_internal(fcinfo, false);
}
Datum
jsonb_path_query_array_tz(PG_FUNCTION_ARGS)
{
return jsonb_path_query_array_internal(fcinfo, true);
}
/*
* jsonb_path_query_first
* Executes jsonpath for given jsonb document and returns first result
* item. If there are no items, NULL returned.
*/
Datum
jsonb_path_query_first(PG_FUNCTION_ARGS)
static Datum
jsonb_path_query_first_internal(FunctionCallInfo fcinfo, bool tz)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
JsonPath *jp = PG_GETARG_JSONPATH_P(1);
@ -439,7 +495,7 @@ jsonb_path_query_first(PG_FUNCTION_ARGS)
Jsonb *vars = PG_GETARG_JSONB_P(2);
bool silent = PG_GETARG_BOOL(3);
(void) executeJsonPath(jp, vars, jb, !silent, &found);
(void) executeJsonPath(jp, vars, jb, !silent, &found, tz);
if (JsonValueListLength(&found) >= 1)
PG_RETURN_JSONB_P(JsonbValueToJsonb(JsonValueListHead(&found)));
@ -447,6 +503,18 @@ jsonb_path_query_first(PG_FUNCTION_ARGS)
PG_RETURN_NULL();
}
Datum
jsonb_path_query_first(PG_FUNCTION_ARGS)
{
return jsonb_path_query_first_internal(fcinfo, false);
}
Datum
jsonb_path_query_first_tz(PG_FUNCTION_ARGS)
{
return jsonb_path_query_first_internal(fcinfo, true);
}
/********************Execute functions for JsonPath**************************/
/*
@ -470,7 +538,7 @@ jsonb_path_query_first(PG_FUNCTION_ARGS)
*/
static JsonPathExecResult
executeJsonPath(JsonPath *path, Jsonb *vars, Jsonb *json, bool throwErrors,
JsonValueList *result)
JsonValueList *result, bool useTz)
{
JsonPathExecContext cxt;
JsonPathExecResult res;
@ -500,6 +568,7 @@ executeJsonPath(JsonPath *path, Jsonb *vars, Jsonb *json, bool throwErrors,
cxt.lastGeneratedObjectId = vars ? 2 : 1;
cxt.innermostArraySize = -1;
cxt.throwErrors = throwErrors;
cxt.useTz = useTz;
if (jspStrictAbsenseOfErrors(&cxt) && !result)
{
@ -1028,6 +1097,12 @@ executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
}
break;
case jpiDatetime:
if (unwrap && JsonbType(jb) == jbvArray)
return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
return executeDateTimeMethod(cxt, jsp, jb, found);
case jpiKeyValue:
if (unwrap && JsonbType(jb) == jbvArray)
return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
@ -1214,7 +1289,7 @@ executeBoolItem(JsonPathExecContext *cxt, JsonPathItem *jsp,
jspGetLeftArg(jsp, &larg);
jspGetRightArg(jsp, &rarg);
return executePredicate(cxt, jsp, &larg, &rarg, jb, true,
executeComparison, NULL);
executeComparison, cxt);
case jpiStartsWith: /* 'whole STARTS WITH initial' */
jspGetLeftArg(jsp, &larg); /* 'whole' */
@ -1693,6 +1768,136 @@ executeNumericItemMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
return executeNextItem(cxt, jsp, &next, jb, found, false);
}
/*
* Implementation of the .datetime() method.
*
* Converts a string into a date/time value. The actual type is determined at run time.
* If an argument is provided, this argument is used as a template string.
* Otherwise, the first fitting ISO format is selected.
*/
static JsonPathExecResult
executeDateTimeMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
JsonbValue *jb, JsonValueList *found)
{
JsonbValue jbvbuf;
Datum value;
text *datetime;
Oid typid;
int32 typmod = -1;
int tz = 0;
bool hasNext;
JsonPathExecResult res = jperNotFound;
JsonPathItem elem;
if (!(jb = getScalar(jb, jbvString)))
RETURN_ERROR(ereport(ERROR,
(errcode(ERRCODE_INVALID_ARGUMENT_FOR_JSON_DATETIME_FUNCTION),
errmsg("jsonpath item method .%s() can only be applied to a string",
jspOperationName(jsp->type)))));
datetime = cstring_to_text_with_len(jb->val.string.val,
jb->val.string.len);
if (jsp->content.arg)
{
text *template;
char *template_str;
int template_len;
bool have_error = false;
jspGetArg(jsp, &elem);
if (elem.type != jpiString)
elog(ERROR, "invalid jsonpath item type for .datetime() argument");
template_str = jspGetString(&elem, &template_len);
template = cstring_to_text_with_len(template_str,
template_len);
value = parse_datetime(datetime, template, true,
&typid, &typmod, &tz,
jspThrowErrors(cxt) ? NULL : &have_error);
if (have_error)
res = jperError;
else
res = jperOk;
}
else
{
/*
* According to SQL/JSON standard enumerate ISO formats for: date,
* timetz, time, timestamptz, timestamp.
*/
static const char *fmt_str[] =
{
"yyyy-mm-dd",
"HH24:MI:SS TZH:TZM",
"HH24:MI:SS TZH",
"HH24:MI:SS",
"yyyy-mm-dd HH24:MI:SS TZH:TZM",
"yyyy-mm-dd HH24:MI:SS TZH",
"yyyy-mm-dd HH24:MI:SS"
};
/* cache for format texts */
static text *fmt_txt[lengthof(fmt_str)] = {0};
int i;
/* loop until datetime format fits */
for (i = 0; i < lengthof(fmt_str); i++)
{
bool have_error = false;
if (!fmt_txt[i])
{
MemoryContext oldcxt =
MemoryContextSwitchTo(TopMemoryContext);
fmt_txt[i] = cstring_to_text(fmt_str[i]);
MemoryContextSwitchTo(oldcxt);
}
value = parse_datetime(datetime, fmt_txt[i], true,
&typid, &typmod, &tz,
&have_error);
if (!have_error)
{
res = jperOk;
break;
}
}
if (res == jperNotFound)
RETURN_ERROR(ereport(ERROR,
(errcode(ERRCODE_INVALID_ARGUMENT_FOR_JSON_DATETIME_FUNCTION),
errmsg("datetime format is not unrecognized"),
errhint("use datetime template argument for explicit format specification"))));
}
pfree(datetime);
if (jperIsError(res))
return res;
hasNext = jspGetNext(jsp, &elem);
if (!hasNext && !found)
return res;
jb = hasNext ? &jbvbuf : palloc(sizeof(*jb));
jb->type = jbvDatetime;
jb->val.datetime.value = value;
jb->val.datetime.typid = typid;
jb->val.datetime.typmod = typmod;
jb->val.datetime.tz = tz;
return executeNextItem(cxt, jsp, &elem, jb, found, hasNext);
}
/*
* Implementation of .keyvalue() method.
*
@ -1953,7 +2158,9 @@ JsonbArraySize(JsonbValue *jb)
static JsonPathBool
executeComparison(JsonPathItem *cmp, JsonbValue *lv, JsonbValue *rv, void *p)
{
return compareItems(cmp->type, lv, rv);
JsonPathExecContext *cxt = (JsonPathExecContext *) p;
return compareItems(cmp->type, lv, rv, cxt->useTz);
}
/*
@ -2048,7 +2255,7 @@ compareStrings(const char *mbstr1, int mblen1,
* Compare two SQL/JSON items using comparison operation 'op'.
*/
static JsonPathBool
compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2)
compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2, bool useTz)
{
int cmp;
bool res;
@ -2089,6 +2296,21 @@ compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2)
cmp = compareStrings(jb1->val.string.val, jb1->val.string.len,
jb2->val.string.val, jb2->val.string.len);
break;
case jbvDatetime:
{
bool have_error = false;
cmp = compareDatetime(jb1->val.datetime.value,
jb1->val.datetime.typid,
jb2->val.datetime.value,
jb2->val.datetime.typid,
useTz,
&have_error);
if (have_error)
return jpbUnknown;
}
break;
case jbvBinary:
case jbvArray:
@ -2348,3 +2570,205 @@ wrapItemsInArray(const JsonValueList *items)
return pushJsonbValue(&ps, WJB_END_ARRAY, NULL);
}
/*
* Cross-type comparison of two datetime SQL/JSON items. If items are
* uncomparable, 'error' flag is set.
*/
static int
compareDatetime(Datum val1, Oid typid1, Datum val2, Oid typid2,
bool useTz, bool *have_error)
{
PGFunction cmpfunc = NULL;
switch (typid1)
{
case DATEOID:
switch (typid2)
{
case DATEOID:
cmpfunc = date_cmp;
break;
case TIMESTAMPOID:
val1 = date2timestamp_opt_error(val1, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMESTAMPTZOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"date", "timestamptz"),
errhint("use *_tz() function for timezone support")));
val1 = date2timestamptz_opt_error(val1, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMEOID:
case TIMETZOID:
*have_error = true;
return 0;
}
break;
case TIMEOID:
switch (typid2)
{
case TIMEOID:
cmpfunc = time_cmp;
break;
case TIMETZOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"time", "timetz"),
errhint("use *_tz() function for timezone support")));
val1 = DirectFunctionCall1(time_timetz, val1);
cmpfunc = timetz_cmp;
break;
case DATEOID:
case TIMESTAMPOID:
case TIMESTAMPTZOID:
*have_error = true;
return 0;
}
break;
case TIMETZOID:
switch (typid2)
{
case TIMEOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"time", "timetz"),
errhint("use *_tz() function for timezone support")));
val2 = DirectFunctionCall1(time_timetz, val2);
cmpfunc = timetz_cmp;
break;
case TIMETZOID:
cmpfunc = timetz_cmp;
break;
case DATEOID:
case TIMESTAMPOID:
case TIMESTAMPTZOID:
*have_error = true;
return 0;
}
break;
case TIMESTAMPOID:
switch (typid2)
{
case DATEOID:
val2 = date2timestamp_opt_error(val2, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMESTAMPOID:
cmpfunc = timestamp_cmp;
break;
case TIMESTAMPTZOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"timestamp", "timestamptz"),
errhint("use *_tz() function for timezone support")));
val1 = timestamp2timestamptz_opt_error(val1, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMEOID:
case TIMETZOID:
*have_error = true;
return 0;
}
break;
case TIMESTAMPTZOID:
switch (typid2)
{
case DATEOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"date", "timestamptz"),
errhint("use *_tz() function for timezone support")));
val2 = date2timestamptz_opt_error(val2, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMESTAMPOID:
if (!useTz)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot convert value from %s to %s without timezone usage",
"timestamp", "timestamptz"),
errhint("use *_tz() function for timezone support")));
val2 = timestamp2timestamptz_opt_error(val2, have_error);
if (have_error && *have_error)
return 0;
cmpfunc = timestamp_cmp;
break;
case TIMESTAMPTZOID:
cmpfunc = timestamp_cmp;
break;
case TIMEOID:
case TIMETZOID:
*have_error = true;
return 0;
}
break;
default:
elog(ERROR, "unrecognized SQL/JSON datetime type oid: %d",
typid1);
}
if (*have_error)
return 0;
if (!cmpfunc)
elog(ERROR, "unrecognized SQL/JSON datetime type oid: %d",
typid2);
*have_error = false;
return DatumGetInt32(DirectFunctionCall2(cmpfunc, val1, val2));
}