copyto_json.000.diff

diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index cfad47b..bc1f684 100644
*** a/src/backend/commands/copy.c
--- b/src/backend/commands/copy.c
*************** ProcessCopyOptions(ParseState *pstate,
*** 443,448 ****
--- 443,450 ----
  				 /* default format */ ;
  			else if (strcmp(fmt, "csv") == 0)
  				opts_out->csv_mode = true;
+ 			else if (strcmp(fmt, "json") == 0)
+ 				opts_out->json_mode = true;
  			else if (strcmp(fmt, "binary") == 0)
  				opts_out->binary = true;
  			else
*************** ProcessCopyOptions(ParseState *pstate,
*** 667,672 ****
--- 669,679 ----
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("cannot specify HEADER in BINARY mode")));
  
+ 	if (opts_out->json_mode && opts_out->header_line)
+ 		ereport(ERROR,
+ 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ 				 errmsg("cannot specify HEADER in JSON mode")));
+ 
  	/* Check quote */
  	if (!opts_out->csv_mode && opts_out->quote != NULL)
  		ereport(ERROR,
diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c
index c66a047..f6ee771 100644
*** a/src/backend/commands/copyto.c
--- b/src/backend/commands/copyto.c
***************
*** 37,42 ****
--- 37,43 ----
  #include "rewrite/rewriteHandler.h"
  #include "storage/fd.h"
  #include "tcop/tcopprot.h"
+ #include "utils/json.h"
  #include "utils/lsyscache.h"
  #include "utils/memutils.h"
  #include "utils/partcache.h"
*************** typedef struct
*** 112,117 ****
--- 113,120 ----
  /* NOTE: there's a copy of this in copyfromparse.c */
  static const char BinarySignature[11] = "PGCOPY\n\377\r\n\0";
  
+ /* need delimiter to start next json array element */
+ static bool json_row_delim_needed = false;
  
  /* non-export function prototypes */
  static void EndCopy(CopyToState cstate);
*************** DoCopyTo(CopyToState cstate)
*** 845,850 ****
--- 848,861 ----
  
  			CopySendEndOfRow(cstate);
  		}
+ 
+ 		/* if a JSON has been requested send the opening bracket */
+ 		if (cstate->opts.json_mode)
+ 		{
+ 			CopySendChar(cstate, '[');
+ 			CopySendEndOfRow(cstate);
+ 			json_row_delim_needed = false;
+ 		}
  	}
  
  	if (cstate->rel)
*************** DoCopyTo(CopyToState cstate)
*** 892,897 ****
--- 903,915 ----
  		CopySendEndOfRow(cstate);
  	}
  
+ 	/* if a JSON has been requested send the closing bracket */
+ 	if (cstate->opts.json_mode)
+ 	{
+ 		CopySendChar(cstate, ']');
+ 		CopySendEndOfRow(cstate);
+ 	}
+ 
  	MemoryContextDelete(cstate->rowcontext);
  
  	if (fe_copy)
*************** DoCopyTo(CopyToState cstate)
*** 906,916 ****
  static void
  CopyOneRowTo(CopyToState cstate, TupleTableSlot *slot)
  {
- 	bool		need_delim = false;
- 	FmgrInfo   *out_functions = cstate->out_functions;
  	MemoryContext oldcontext;
- 	ListCell   *cur;
- 	char	   *string;
  
  	MemoryContextReset(cstate->rowcontext);
  	oldcontext = MemoryContextSwitchTo(cstate->rowcontext);
--- 924,930 ----
*************** CopyOneRowTo(CopyToState cstate, TupleTa
*** 921,974 ****
  		CopySendInt16(cstate, list_length(cstate->attnumlist));
  	}
  
! 	/* Make sure the tuple is fully deconstructed */
! 	slot_getallattrs(slot);
! 
! 	foreach(cur, cstate->attnumlist)
  	{
! 		int			attnum = lfirst_int(cur);
! 		Datum		value = slot->tts_values[attnum - 1];
! 		bool		isnull = slot->tts_isnull[attnum - 1];
  
! 		if (!cstate->opts.binary)
! 		{
! 			if (need_delim)
! 				CopySendChar(cstate, cstate->opts.delim[0]);
! 			need_delim = true;
! 		}
  
! 		if (isnull)
! 		{
! 			if (!cstate->opts.binary)
! 				CopySendString(cstate, cstate->opts.null_print_client);
! 			else
! 				CopySendInt32(cstate, -1);
! 		}
! 		else
  		{
  			if (!cstate->opts.binary)
  			{
! 				string = OutputFunctionCall(&out_functions[attnum - 1],
! 											value);
! 				if (cstate->opts.csv_mode)
! 					CopyAttributeOutCSV(cstate, string,
! 										cstate->opts.force_quote_flags[attnum - 1],
! 										list_length(cstate->attnumlist) == 1);
  				else
! 					CopyAttributeOutText(cstate, string);
  			}
  			else
  			{
! 				bytea	   *outputbytes;
  
! 				outputbytes = SendFunctionCall(&out_functions[attnum - 1],
! 											   value);
! 				CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ);
! 				CopySendData(cstate, VARDATA(outputbytes),
! 							 VARSIZE(outputbytes) - VARHDRSZ);
  			}
  		}
  	}
  
  	CopySendEndOfRow(cstate);
  
--- 935,1015 ----
  		CopySendInt16(cstate, list_length(cstate->attnumlist));
  	}
  
! 	if (!cstate->opts.json_mode)
  	{
! 		bool		need_delim = false;
! 		FmgrInfo   *out_functions = cstate->out_functions;
! 		ListCell   *cur;
! 		char	   *string;
  
! 		/* Make sure the tuple is fully deconstructed */
! 		slot_getallattrs(slot);
  
! 		foreach(cur, cstate->attnumlist)
  		{
+ 			int			attnum = lfirst_int(cur);
+ 			Datum		value = slot->tts_values[attnum - 1];
+ 			bool		isnull = slot->tts_isnull[attnum - 1];
+ 
  			if (!cstate->opts.binary)
  			{
! 				if (need_delim)
! 					CopySendChar(cstate, cstate->opts.delim[0]);
! 				need_delim = true;
! 			}
! 
! 			if (isnull)
! 			{
! 				if (!cstate->opts.binary)
! 					CopySendString(cstate, cstate->opts.null_print_client);
  				else
! 					CopySendInt32(cstate, -1);
  			}
  			else
  			{
! 				if (!cstate->opts.binary)
! 				{
! 					string = OutputFunctionCall(&out_functions[attnum - 1],
! 												value);
! 					if (cstate->opts.csv_mode)
! 						CopyAttributeOutCSV(cstate, string,
! 											cstate->opts.force_quote_flags[attnum - 1],
! 											list_length(cstate->attnumlist) == 1);
! 					else
! 						CopyAttributeOutText(cstate, string);
! 				}
! 				else
! 				{
! 					bytea	   *outputbytes;
  
! 					outputbytes = SendFunctionCall(&out_functions[attnum - 1],
! 												   value);
! 					CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ);
! 					CopySendData(cstate, VARDATA(outputbytes),
! 								 VARSIZE(outputbytes) - VARHDRSZ);
! 				}
  			}
  		}
  	}
+ 	else
+ 	{
+ 		Datum	rowdata = ExecFetchSlotHeapTupleDatum(slot);
+ 		StringInfo	result;
+ 
+ 		result = makeStringInfo();
+ 		composite_to_json(rowdata, result, false);
+ 
+ 		if (json_row_delim_needed)
+ 			CopySendChar(cstate, ',');
+ 		else
+ 		{
+ 			/* first row needs no delimiter */
+ 			CopySendChar(cstate, ' ');
+ 			json_row_delim_needed = true;
+ 		}
+ 
+ 		CopyAttributeOutText(cstate, result->data);
+ 	}
  
  	CopySendEndOfRow(cstate);
  
diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c
index 71ae53f..cb4311e 100644
*** a/src/backend/utils/adt/json.c
--- b/src/backend/utils/adt/json.c
*************** typedef struct JsonAggState
*** 83,90 ****
  	JsonUniqueBuilderState unique_check;
  } JsonAggState;
  
- static void composite_to_json(Datum composite, StringInfo result,
- 							  bool use_line_feeds);
  static void array_dim_to_json(StringInfo result, int dim, int ndims, int *dims,
  							  Datum *vals, bool *nulls, int *valcount,
  							  JsonTypeCategory tcategory, Oid outfuncoid,
--- 83,88 ----
*************** array_to_json_internal(Datum array, Stri
*** 490,497 ****
  
  /*
   * Turn a composite / record into JSON.
   */
! static void
  composite_to_json(Datum composite, StringInfo result, bool use_line_feeds)
  {
  	HeapTupleHeader td;
--- 488,496 ----
  
  /*
   * Turn a composite / record into JSON.
+  * Exported so COPY TO can use it.
   */
! void
  composite_to_json(Datum composite, StringInfo result, bool use_line_feeds)
  {
  	HeapTupleHeader td;
diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h
index f2cca0b..e66bd01 100644
*** a/src/include/commands/copy.h
--- b/src/include/commands/copy.h
*************** typedef struct CopyFormatOptions
*** 43,48 ****
--- 43,49 ----
  	bool		binary;			/* binary format? */
  	bool		freeze;			/* freeze rows on loading? */
  	bool		csv_mode;		/* Comma Separated Value format? */
+ 	bool		json_mode;		/* JSON format? */
  	CopyHeaderChoice header_line;	/* header line? */
  	char	   *null_print;		/* NULL marker string (server encoding!) */
  	int			null_print_len; /* length of same */
diff --git a/src/include/utils/json.h b/src/include/utils/json.h
index f07e82c..badc5a6 100644
*** a/src/include/utils/json.h
--- b/src/include/utils/json.h
***************
*** 17,22 ****
--- 17,24 ----
  #include "lib/stringinfo.h"
  
  /* functions in json.c */
+ extern void composite_to_json(Datum composite, StringInfo result,
+ 							  bool use_line_feeds);
  extern void escape_json(StringInfo buf, const char *str);
  extern char *JsonEncodeDateTime(char *buf, Datum value, Oid typid,
  								const int *tzp);