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#include "redismodule.h"
#include <string.h>
#include <strings.h>
#include <assert.h>
#include <unistd.h>
#include <errno.h>
/* Command which adds a stream entry with automatic ID, like XADD *.
*
* Syntax: STREAM.ADD key field1 value1 [ field2 value2 ... ]
*
* The response is the ID of the added stream entry or an error message.
*/
int stream_add(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
if (argc < 2 || argc % 2 != 0) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
RedisModuleStreamID id;
if (RedisModule_StreamAdd(key, REDISMODULE_STREAM_ADD_AUTOID, &id,
&argv[2], (argc-2)/2) == REDISMODULE_OK) {
RedisModuleString *id_str = RedisModule_CreateStringFromStreamID(ctx, &id);
RedisModule_ReplyWithString(ctx, id_str);
RedisModule_FreeString(ctx, id_str);
} else {
RedisModule_ReplyWithError(ctx, "ERR StreamAdd failed");
}
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
/* Command which adds a stream entry N times.
*
* Syntax: STREAM.ADD key N field1 value1 [ field2 value2 ... ]
*
* Returns the number of successfully added entries.
*/
int stream_addn(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
if (argc < 3 || argc % 2 == 0) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
long long n, i;
if (RedisModule_StringToLongLong(argv[2], &n) == REDISMODULE_ERR) {
RedisModule_ReplyWithError(ctx, "N must be a number");
return REDISMODULE_OK;
}
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
for (i = 0; i < n; i++) {
if (RedisModule_StreamAdd(key, REDISMODULE_STREAM_ADD_AUTOID, NULL,
&argv[3], (argc-3)/2) == REDISMODULE_ERR)
break;
}
RedisModule_ReplyWithLongLong(ctx, i);
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
/* STREAM.DELETE key stream-id */
int stream_delete(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
if (argc != 3) return RedisModule_WrongArity(ctx);
RedisModuleStreamID id;
if (RedisModule_StringToStreamID(argv[2], &id) != REDISMODULE_OK) {
return RedisModule_ReplyWithError(ctx, "Invalid stream ID");
}
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
if (RedisModule_StreamDelete(key, &id) == REDISMODULE_OK) {
RedisModule_ReplyWithSimpleString(ctx, "OK");
} else {
RedisModule_ReplyWithError(ctx, "ERR StreamDelete failed");
}
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
/* STREAM.RANGE key start-id end-id
*
* Returns an array of stream items. Each item is an array on the form
* [stream-id, [field1, value1, field2, value2, ...]].
*
* A funny side-effect used for testing RM_StreamIteratorDelete() is that if any
* entry has a field named "selfdestruct", the stream entry is deleted. It is
* however included in the results of this command.
*/
int stream_range(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
if (argc != 4) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
RedisModuleStreamID startid, endid;
if (RedisModule_StringToStreamID(argv[2], &startid) != REDISMODULE_OK ||
RedisModule_StringToStreamID(argv[3], &endid) != REDISMODULE_OK) {
RedisModule_ReplyWithError(ctx, "Invalid stream ID");
return REDISMODULE_OK;
}
/* If startid > endid, we swap and set the reverse flag. */
int flags = 0;
if (startid.ms > endid.ms ||
(startid.ms == endid.ms && startid.seq > endid.seq)) {
RedisModuleStreamID tmp = startid;
startid = endid;
endid = tmp;
flags |= REDISMODULE_STREAM_ITERATOR_REVERSE;
}
/* Open key and start iterator. */
int openflags = REDISMODULE_READ | REDISMODULE_WRITE;
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], openflags);
if (RedisModule_StreamIteratorStart(key, flags,
&startid, &endid) != REDISMODULE_OK) {
/* Key is not a stream, etc. */
RedisModule_ReplyWithError(ctx, "ERR StreamIteratorStart failed");
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
/* Check error handling: Delete current entry when no current entry. */
assert(RedisModule_StreamIteratorDelete(key) ==
REDISMODULE_ERR);
assert(errno == ENOENT);
/* Check error handling: Fetch fields when no current entry. */
assert(RedisModule_StreamIteratorNextField(key, NULL, NULL) ==
REDISMODULE_ERR);
assert(errno == ENOENT);
/* Return array. */
RedisModule_ReplyWithArray(ctx, REDISMODULE_POSTPONED_LEN);
RedisModule_AutoMemory(ctx);
RedisModuleStreamID id;
long numfields;
long len = 0;
while (RedisModule_StreamIteratorNextID(key, &id,
&numfields) == REDISMODULE_OK) {
RedisModule_ReplyWithArray(ctx, 2);
RedisModuleString *id_str = RedisModule_CreateStringFromStreamID(ctx, &id);
RedisModule_ReplyWithString(ctx, id_str);
RedisModule_ReplyWithArray(ctx, numfields * 2);
int delete = 0;
RedisModuleString *field, *value;
for (long i = 0; i < numfields; i++) {
assert(RedisModule_StreamIteratorNextField(key, &field, &value) ==
REDISMODULE_OK);
RedisModule_ReplyWithString(ctx, field);
RedisModule_ReplyWithString(ctx, value);
/* check if this is a "selfdestruct" field */
size_t field_len;
const char *field_str = RedisModule_StringPtrLen(field, &field_len);
if (!strncmp(field_str, "selfdestruct", field_len)) delete = 1;
}
if (delete) {
assert(RedisModule_StreamIteratorDelete(key) == REDISMODULE_OK);
}
/* check error handling: no more fields to fetch */
assert(RedisModule_StreamIteratorNextField(key, &field, &value) ==
REDISMODULE_ERR);
assert(errno == ENOENT);
len++;
}
RedisModule_ReplySetArrayLength(ctx, len);
RedisModule_StreamIteratorStop(key);
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
/*
* STREAM.TRIM key (MAXLEN (=|~) length | MINID (=|~) id)
*/
int stream_trim(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
if (argc != 5) {
RedisModule_WrongArity(ctx);
return REDISMODULE_OK;
}
/* Parse args */
int trim_by_id = 0; /* 0 = maxlen, 1 = minid */
long long maxlen;
RedisModuleStreamID minid;
size_t arg_len;
const char *arg = RedisModule_StringPtrLen(argv[2], &arg_len);
if (!strcasecmp(arg, "minid")) {
trim_by_id = 1;
if (RedisModule_StringToStreamID(argv[4], &minid) != REDISMODULE_OK) {
RedisModule_ReplyWithError(ctx, "ERR Invalid stream ID");
return REDISMODULE_OK;
}
} else if (!strcasecmp(arg, "maxlen")) {
if (RedisModule_StringToLongLong(argv[4], &maxlen) == REDISMODULE_ERR) {
RedisModule_ReplyWithError(ctx, "ERR Maxlen must be a number");
return REDISMODULE_OK;
}
} else {
RedisModule_ReplyWithError(ctx, "ERR Invalid arguments");
return REDISMODULE_OK;
}
/* Approx or exact */
int flags;
arg = RedisModule_StringPtrLen(argv[3], &arg_len);
if (arg_len == 1 && arg[0] == '~') {
flags = REDISMODULE_STREAM_TRIM_APPROX;
} else if (arg_len == 1 && arg[0] == '=') {
flags = 0;
} else {
RedisModule_ReplyWithError(ctx, "ERR Invalid approx-or-exact mark");
return REDISMODULE_OK;
}
/* Trim */
RedisModuleKey *key = RedisModule_OpenKey(ctx, argv[1], REDISMODULE_WRITE);
long long trimmed;
if (trim_by_id) {
trimmed = RedisModule_StreamTrimByID(key, flags, &minid);
} else {
trimmed = RedisModule_StreamTrimByLength(key, flags, maxlen);
}
/* Return result */
if (trimmed < 0) {
RedisModule_ReplyWithError(ctx, "ERR Trimming failed");
} else {
RedisModule_ReplyWithLongLong(ctx, trimmed);
}
RedisModule_CloseKey(key);
return REDISMODULE_OK;
}
int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
REDISMODULE_NOT_USED(argv);
REDISMODULE_NOT_USED(argc);
if (RedisModule_Init(ctx, "stream", 1, REDISMODULE_APIVER_1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "stream.add", stream_add, "write",
1, 1, 1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "stream.addn", stream_addn, "write",
1, 1, 1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "stream.delete", stream_delete, "write",
1, 1, 1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "stream.range", stream_range, "write",
1, 1, 1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_CreateCommand(ctx, "stream.trim", stream_trim, "write",
1, 1, 1) == REDISMODULE_ERR)
return REDISMODULE_ERR;
return REDISMODULE_OK;
}
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