Merge pull request #6270 from oranagra/modules_info

Extend modules API to allow modules report to redis INFO

9 files changed, 365 insertions, 6 deletions

diff --git a/runtest-moduleapi b/runtest-moduleapi
index e785447db..1f090ff65 100755
--- a/runtest-moduleapi
+++ b/runtest-moduleapi
@@ -13,4 +13,4 @@ then
 fi
 
 make -C tests/modules && \
-$TCLSH tests/test_helper.tcl --single unit/moduleapi/commandfilter --single unit/moduleapi/fork --single unit/moduleapi/testrdb "${@}"
+$TCLSH tests/test_helper.tcl --single unit/moduleapi/commandfilter --single unit/moduleapi/fork --single unit/moduleapi/testrdb --single unit/moduleapi/infotest "${@}"
diff --git a/src/debug.c b/src/debug.c
index 0d29165de..15db2157f 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -1365,6 +1365,12 @@ void sigsegvHandler(int sig, siginfo_t *info, void *secret) {
     /* Log dump of processor registers */
     logRegisters(uc);
 
+    /* Log Modules INFO */
+    serverLogRaw(LL_WARNING|LL_RAW, "\n------ MODULES INFO OUTPUT ------\n");
+    infostring = modulesCollectInfo(sdsempty(), NULL, 1, 0);
+    serverLogRaw(LL_WARNING|LL_RAW, infostring);
+    sdsfree(infostring);
+
 #if defined(HAVE_PROC_MAPS)
     /* Test memory */
     serverLogRaw(LL_WARNING|LL_RAW, "\n------ FAST MEMORY TEST ------\n");
diff --git a/src/module.c b/src/module.c
index 13353df2c..18622bd6b 100644
--- a/src/module.c
+++ b/src/module.c
@@ -42,6 +42,17 @@
  * pointers that have an API the module can call with them)
  * -------------------------------------------------------------------------- */
 
+typedef struct RedisModuleInfoCtx {
+    struct RedisModule *module;
+    sds requested_section;
+    sds info;           /* info string we collected so far */
+    int sections;       /* number of sections we collected so far */
+    int in_section;     /* indication if we're in an active section or not */
+    int in_dict_field;  /* indication that we're curreintly appending to a dict */
+} RedisModuleInfoCtx;
+
+typedef void (*RedisModuleInfoFunc)(RedisModuleInfoCtx *ctx, int for_crash_report);
+
 /* This structure represents a module inside the system. */
 struct RedisModule {
     void *handle;   /* Module dlopen() handle. */
@@ -54,6 +65,7 @@ struct RedisModule {
     list *filters;  /* List of filters the module has registered. */
     int in_call;    /* RM_Call() nesting level */
     int options;    /* Module options and capabilities. */
+    RedisModuleInfoFunc info_cb;     /* callback for module to add INFO fields. */
 };
 typedef struct RedisModule RedisModule;
 
@@ -4796,6 +4808,194 @@ int RM_DictCompare(RedisModuleDictIter *di, const char *op, RedisModuleString *k
     return res ? REDISMODULE_OK : REDISMODULE_ERR;
 }
 
+
+
+
+/* --------------------------------------------------------------------------
+ * Modules Info fields
+ * -------------------------------------------------------------------------- */
+
+int RM_InfoEndDictField(RedisModuleInfoCtx *ctx);
+
+/* Used to start a new section, before adding any fields. the section name will
+ * be prefixed by "<modulename>_" and must only include A-Z,a-z,0-9.
+ * NULL or empty string indicates the default section (only <modulename>) is used.
+ * When return value is REDISMODULE_ERR, the section should and will be skipped. */
+int RM_InfoAddSection(RedisModuleInfoCtx *ctx, char *name) {
+    sds full_name = sdsdup(ctx->module->name);
+    if (name != NULL && strlen(name) > 0)
+        full_name = sdscatfmt(full_name, "_%s", name);
+
+    /* Implicitly end dicts, instead of returning an error which is likely un checked. */
+    if (ctx->in_dict_field)
+        RM_InfoEndDictField(ctx);
+
+    /* proceed only if:
+     * 1) no section was requested (emit all)
+     * 2) the module name was requested (emit all)
+     * 3) this specific section was requested. */
+    if (ctx->requested_section) {
+        if (strcasecmp(ctx->requested_section, full_name) &&
+            strcasecmp(ctx->requested_section, ctx->module->name)) {
+            sdsfree(full_name);
+            ctx->in_section = 0;
+            return REDISMODULE_ERR;
+        }
+    }
+    if (ctx->sections++) ctx->info = sdscat(ctx->info,"\r\n");
+    ctx->info = sdscatfmt(ctx->info, "# %S\r\n", full_name);
+    ctx->in_section = 1;
+    sdsfree(full_name);
+    return REDISMODULE_OK;
+}
+
+/* Starts a dict field, similar to the ones in INFO KEYSPACE. Use normal
+ * RedisModule_InfoAddField* functions to add the items to this field, and
+ * terminate with RedisModule_InfoEndDictField. */
+int RM_InfoBeginDictField(RedisModuleInfoCtx *ctx, char *name) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    /* Implicitly end dicts, instead of returning an error which is likely un checked. */
+    if (ctx->in_dict_field)
+        RM_InfoEndDictField(ctx);
+    ctx->info = sdscatfmt(ctx->info,
+        "%s_%s:",
+        ctx->module->name,
+        name);
+    ctx->in_dict_field = 1;
+    return REDISMODULE_OK;
+}
+
+/* Ends a dict field, see RedisModule_InfoBeginDictField */
+int RM_InfoEndDictField(RedisModuleInfoCtx *ctx) {
+    if (!ctx->in_dict_field)
+        return REDISMODULE_ERR;
+    /* trim the last ',' if found. */
+    if (ctx->info[sdslen(ctx->info)-1]==',')
+        sdsIncrLen(ctx->info, -1);
+    ctx->info = sdscat(ctx->info, "\r\n");
+    ctx->in_dict_field = 0;
+    return REDISMODULE_OK;
+}
+
+/* Used by RedisModuleInfoFunc to add info fields.
+ * Each field will be automatically prefixed by "<modulename>_".
+ * Field names or values must not include \r\n of ":" */
+int RM_InfoAddFieldString(RedisModuleInfoCtx *ctx, char *field, RedisModuleString *value) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    if (ctx->in_dict_field) {
+        ctx->info = sdscatfmt(ctx->info,
+            "%s=%S,",
+            field,
+            (sds)value->ptr);
+        return REDISMODULE_OK;
+    }
+    ctx->info = sdscatfmt(ctx->info,
+        "%s_%s:%S\r\n",
+        ctx->module->name,
+        field,
+        (sds)value->ptr);
+    return REDISMODULE_OK;
+}
+
+int RM_InfoAddFieldCString(RedisModuleInfoCtx *ctx, char *field, char *value) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    if (ctx->in_dict_field) {
+        ctx->info = sdscatfmt(ctx->info,
+            "%s=%s,",
+            field,
+            value);
+        return REDISMODULE_OK;
+    }
+    ctx->info = sdscatfmt(ctx->info,
+        "%s_%s:%s\r\n",
+        ctx->module->name,
+        field,
+        value);
+    return REDISMODULE_OK;
+}
+
+int RM_InfoAddFieldDouble(RedisModuleInfoCtx *ctx, char *field, double value) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    if (ctx->in_dict_field) {
+        ctx->info = sdscatprintf(ctx->info,
+            "%s=%.17g,",
+            field,
+            value);
+        return REDISMODULE_OK;
+    }
+    ctx->info = sdscatprintf(ctx->info,
+        "%s_%s:%.17g\r\n",
+        ctx->module->name,
+        field,
+        value);
+    return REDISMODULE_OK;
+}
+
+int RM_InfoAddFieldLongLong(RedisModuleInfoCtx *ctx, char *field, long long value) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    if (ctx->in_dict_field) {
+        ctx->info = sdscatfmt(ctx->info,
+            "%s=%I,",
+            field,
+            value);
+        return REDISMODULE_OK;
+    }
+    ctx->info = sdscatfmt(ctx->info,
+        "%s_%s:%I\r\n",
+        ctx->module->name,
+        field,
+        value);
+    return REDISMODULE_OK;
+}
+
+int RM_InfoAddFieldULongLong(RedisModuleInfoCtx *ctx, char *field, unsigned long long value) {
+    if (!ctx->in_section)
+        return REDISMODULE_ERR;
+    if (ctx->in_dict_field) {
+        ctx->info = sdscatfmt(ctx->info,
+            "%s=%U,",
+            field,
+            value);
+        return REDISMODULE_OK;
+    }
+    ctx->info = sdscatfmt(ctx->info,
+        "%s_%s:%U\r\n",
+        ctx->module->name,
+        field,
+        value);
+    return REDISMODULE_OK;
+}
+
+int RM_RegisterInfoFunc(RedisModuleCtx *ctx, RedisModuleInfoFunc cb) {
+    ctx->module->info_cb = cb;
+    return REDISMODULE_OK;
+}
+
+sds modulesCollectInfo(sds info, sds section, int for_crash_report, int sections) {
+    dictIterator *di = dictGetIterator(modules);
+    dictEntry *de;
+
+    while ((de = dictNext(di)) != NULL) {
+        struct RedisModule *module = dictGetVal(de);
+        if (!module->info_cb)
+            continue;
+        RedisModuleInfoCtx info_ctx = {module, section, info, sections, 0};
+        module->info_cb(&info_ctx, for_crash_report);
+        /* Implicitly end dicts (no way to handle errors, and we must add the newline). */
+        if (info_ctx.in_dict_field)
+            RM_InfoEndDictField(&info_ctx);
+        info = info_ctx.info;
+        sections = info_ctx.sections;
+    }
+    dictReleaseIterator(di);
+    return info;
+}
+
 /* --------------------------------------------------------------------------
  * Modules utility APIs
  * -------------------------------------------------------------------------- */
@@ -5512,9 +5712,9 @@ sds genModulesInfoString(sds info) {
         sds usedby = genModulesInfoStringRenderModulesList(module->usedby);
         sds using = genModulesInfoStringRenderModulesList(module->using);
         sds options = genModulesInfoStringRenderModuleOptions(module);
-        info = sdscatprintf(info,
-            "module:name=%s,ver=%d,api=%d,filters=%d,"
-            "usedby=%s,using=%s,options=%s\r\n",
+        info = sdscatfmt(info,
+            "module:name=%S,ver=%i,api=%i,filters=%i,"
+            "usedby=%S,using=%S,options=%S\r\n",
                 name, module->ver, module->apiver,
                 (int)listLength(module->filters), usedby, using, options);
         sdsfree(usedby);
@@ -5761,4 +5961,13 @@ void moduleRegisterCoreAPI(void) {
     REGISTER_API(Fork);
     REGISTER_API(ExitFromChild);
     REGISTER_API(KillForkChild);
+    REGISTER_API(RegisterInfoFunc);
+    REGISTER_API(InfoAddSection);
+    REGISTER_API(InfoBeginDictField);
+    REGISTER_API(InfoEndDictField);
+    REGISTER_API(InfoAddFieldString);
+    REGISTER_API(InfoAddFieldCString);
+    REGISTER_API(InfoAddFieldDouble);
+    REGISTER_API(InfoAddFieldLongLong);
+    REGISTER_API(InfoAddFieldULongLong);
 }
diff --git a/src/redismodule.h b/src/redismodule.h
index 6a3a164b5..851bb8cde 100644
--- a/src/redismodule.h
+++ b/src/redismodule.h
@@ -167,6 +167,7 @@ typedef struct RedisModuleDict RedisModuleDict;
 typedef struct RedisModuleDictIter RedisModuleDictIter;
 typedef struct RedisModuleCommandFilterCtx RedisModuleCommandFilterCtx;
 typedef struct RedisModuleCommandFilter RedisModuleCommandFilter;
+typedef struct RedisModuleInfoCtx RedisModuleInfoCtx;
 
 typedef int (*RedisModuleCmdFunc)(RedisModuleCtx *ctx, RedisModuleString **argv, int argc);
 typedef void (*RedisModuleDisconnectFunc)(RedisModuleCtx *ctx, RedisModuleBlockedClient *bc);
@@ -183,6 +184,7 @@ typedef void (*RedisModuleClusterMessageReceiver)(RedisModuleCtx *ctx, const cha
 typedef void (*RedisModuleTimerProc)(RedisModuleCtx *ctx, void *data);
 typedef void (*RedisModuleCommandFilterFunc) (RedisModuleCommandFilterCtx *filter);
 typedef void (*RedisModuleForkDoneHandler) (int exitcode, int bysignal, void *user_data);
+typedef void (*RedisModuleInfoFunc)(RedisModuleInfoCtx *ctx, int for_crash_report);
 
 #define REDISMODULE_TYPE_METHOD_VERSION 2
 typedef struct RedisModuleTypeMethods {
@@ -333,6 +335,15 @@ RedisModuleString *REDISMODULE_API_FUNC(RedisModule_DictNext)(RedisModuleCtx *ct
 RedisModuleString *REDISMODULE_API_FUNC(RedisModule_DictPrev)(RedisModuleCtx *ctx, RedisModuleDictIter *di, void **dataptr);
 int REDISMODULE_API_FUNC(RedisModule_DictCompareC)(RedisModuleDictIter *di, const char *op, void *key, size_t keylen);
 int REDISMODULE_API_FUNC(RedisModule_DictCompare)(RedisModuleDictIter *di, const char *op, RedisModuleString *key);
+int REDISMODULE_API_FUNC(RedisModule_RegisterInfoFunc)(RedisModuleCtx *ctx, RedisModuleInfoFunc cb);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddSection)(RedisModuleInfoCtx *ctx, char *name);
+int REDISMODULE_API_FUNC(RedisModule_InfoBeginDictField)(RedisModuleInfoCtx *ctx, char *name);
+int REDISMODULE_API_FUNC(RedisModule_InfoEndDictField)(RedisModuleInfoCtx *ctx);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddFieldString)(RedisModuleInfoCtx *ctx, char *field, RedisModuleString *value);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddFieldCString)(RedisModuleInfoCtx *ctx, char *field, char *value);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddFieldDouble)(RedisModuleInfoCtx *ctx, char *field, double value);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddFieldLongLong)(RedisModuleInfoCtx *ctx, char *field, long long value);
+int REDISMODULE_API_FUNC(RedisModule_InfoAddFieldULongLong)(RedisModuleInfoCtx *ctx, char *field, unsigned long long value);
 
 /* Experimental APIs */
 #ifdef REDISMODULE_EXPERIMENTAL_API
@@ -512,6 +523,15 @@ static int RedisModule_Init(RedisModuleCtx *ctx, const char *name, int ver, int
     REDISMODULE_GET_API(DictPrev);
     REDISMODULE_GET_API(DictCompare);
     REDISMODULE_GET_API(DictCompareC);
+    REDISMODULE_GET_API(RegisterInfoFunc);
+    REDISMODULE_GET_API(InfoAddSection);
+    REDISMODULE_GET_API(InfoBeginDictField);
+    REDISMODULE_GET_API(InfoEndDictField);
+    REDISMODULE_GET_API(InfoAddFieldString);
+    REDISMODULE_GET_API(InfoAddFieldCString);
+    REDISMODULE_GET_API(InfoAddFieldDouble);
+    REDISMODULE_GET_API(InfoAddFieldLongLong);
+    REDISMODULE_GET_API(InfoAddFieldULongLong);
 
 #ifdef REDISMODULE_EXPERIMENTAL_API
     REDISMODULE_GET_API(GetThreadSafeContext);
diff --git a/src/server.c b/src/server.c
index cacce6dc2..9380a840a 100644
--- a/src/server.c
+++ b/src/server.c
@@ -3861,12 +3861,15 @@ sds genRedisInfoString(char *section) {
     time_t uptime = server.unixtime-server.stat_starttime;
     int j;
     struct rusage self_ru, c_ru;
-    int allsections = 0, defsections = 0;
+    int allsections = 0, defsections = 0, everything = 0, modules = 0;
     int sections = 0;
 
     if (section == NULL) section = "default";
     allsections = strcasecmp(section,"all") == 0;
     defsections = strcasecmp(section,"default") == 0;
+    everything = strcasecmp(section,"everything") == 0;
+    modules = strcasecmp(section,"modules") == 0;
+    if (everything) allsections = 1;
 
     getrusage(RUSAGE_SELF, &self_ru);
     getrusage(RUSAGE_CHILDREN, &c_ru);
@@ -4425,6 +4428,17 @@ sds genRedisInfoString(char *section) {
             }
         }
     }
+
+    /* Get info from modules.
+     * if user asked for "everything" or "modules", or a specific section
+     * that's not found yet. */
+    if (everything || modules ||
+        (!allsections && !defsections && sections==0)) {
+        info = modulesCollectInfo(info,
+                                  everything || modules ? NULL: section,
+                                  0, /* not a crash report */
+                                  sections);
+    }
     return info;
 }
 
diff --git a/src/server.h b/src/server.h
index 91c7219a0..6e011a2ca 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1555,6 +1555,7 @@ void ModuleForkDoneHandler(int exitcode, int bysignal);
 int TerminateModuleForkChild(int child_pid, int wait);
 ssize_t rdbSaveModulesAux(rio *rdb, int when);
 int moduleAllDatatypesHandleErrors();
+sds modulesCollectInfo(sds info, sds section, int for_crash_report, int sections);
 
 /* Utils */
 long long ustime(void);
diff --git a/tests/modules/Makefile b/tests/modules/Makefile
index 650e757a9..e669d8e5e 100644
--- a/tests/modules/Makefile
+++ b/tests/modules/Makefile
@@ -13,7 +13,7 @@ endif
 
 .SUFFIXES: .c .so .xo .o
 
-all: commandfilter.so testrdb.so fork.so
+all: commandfilter.so testrdb.so fork.so infotest.so
 
 .c.xo:
 	$(CC) -I../../src $(CFLAGS) $(SHOBJ_CFLAGS) -fPIC -c $< -o $@
@@ -21,6 +21,7 @@ all: commandfilter.so testrdb.so fork.so
 commandfilter.xo: ../../src/redismodule.h
 fork.xo: ../../src/redismodule.h
 testrdb.xo: ../../src/redismodule.h
+infotest.xo: ../../src/redismodule.h
 
 commandfilter.so: commandfilter.xo
 	$(LD) -o $@ $< $(SHOBJ_LDFLAGS) $(LIBS) -lc
@@ -30,3 +31,7 @@ fork.so: fork.xo
 
 testrdb.so: testrdb.xo
 	$(LD) -o $@ $< $(SHOBJ_LDFLAGS) $(LIBS) -lc
+
+infotest.so: infotest.xo
+	$(LD) -o $@ $< $(SHOBJ_LDFLAGS) $(LIBS) -lc
+
diff --git a/tests/modules/infotest.c b/tests/modules/infotest.c
new file mode 100644
index 000000000..d28410932
--- /dev/null
+++ b/tests/modules/infotest.c
@@ -0,0 +1,41 @@
+#include "redismodule.h"
+
+#include <string.h>
+
+void InfoFunc(RedisModuleInfoCtx *ctx, int for_crash_report) {
+    RedisModule_InfoAddSection(ctx, "");
+    RedisModule_InfoAddFieldLongLong(ctx, "global", -2);
+
+    RedisModule_InfoAddSection(ctx, "Spanish");
+    RedisModule_InfoAddFieldCString(ctx, "uno", "one");
+    RedisModule_InfoAddFieldLongLong(ctx, "dos", 2);
+
+    RedisModule_InfoAddSection(ctx, "Italian");
+    RedisModule_InfoAddFieldLongLong(ctx, "due", 2);
+    RedisModule_InfoAddFieldDouble(ctx, "tre", 3.3);
+
+    RedisModule_InfoAddSection(ctx, "keyspace");
+    RedisModule_InfoBeginDictField(ctx, "db0");
+    RedisModule_InfoAddFieldLongLong(ctx, "keys", 3);
+    RedisModule_InfoAddFieldLongLong(ctx, "expires", 1);
+    RedisModule_InfoEndDictField(ctx);
+
+    if (for_crash_report) {
+        RedisModule_InfoAddSection(ctx, "Klingon");
+        RedisModule_InfoAddFieldCString(ctx, "one", "wa’");
+        RedisModule_InfoAddFieldCString(ctx, "two", "cha’");
+        RedisModule_InfoAddFieldCString(ctx, "three", "wej");
+    }
+
+}
+
+int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
+    REDISMODULE_NOT_USED(argv);
+    REDISMODULE_NOT_USED(argc);
+    if (RedisModule_Init(ctx,"infotest",1,REDISMODULE_APIVER_1)
+            == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    if (RedisModule_RegisterInfoFunc(ctx, InfoFunc) == REDISMODULE_ERR) return REDISMODULE_ERR;
+
+    return REDISMODULE_OK;
+}
diff --git a/tests/unit/moduleapi/infotest.tcl b/tests/unit/moduleapi/infotest.tcl
new file mode 100644
index 000000000..659ee79d7
--- /dev/null
+++ b/tests/unit/moduleapi/infotest.tcl
@@ -0,0 +1,63 @@
+set testmodule [file normalize tests/modules/infotest.so]
+
+# Return value for INFO property
+proc field {info property} {
+    if {[regexp "\r\n$property:(.*?)\r\n" $info _ value]} {
+        set _ $value
+    }
+}
+
+start_server {tags {"modules"}} {
+    r module load $testmodule log-key 0
+
+    test {module info all} {
+        set info [r info all]
+        # info all does not contain modules
+        assert { ![string match "*Spanish*" $info] }
+        assert { ![string match "*infotest_*" $info] }
+        assert { [string match "*used_memory*" $info] }
+    }
+
+    test {module info everything} {
+        set info [r info everything]
+        # info everything contains all default sections, but not ones for crash report
+        assert { [string match "*infotest_global*" $info] }
+        assert { [string match "*Spanish*" $info] }
+        assert { [string match "*Italian*" $info] }
+        assert { [string match "*used_memory*" $info] }
+        assert { ![string match "*Klingon*" $info] }
+        field $info infotest_dos
+    } {2}
+
+    test {module info modules} {
+        set info [r info modules]
+        # info all does not contain modules
+        assert { [string match "*Spanish*" $info] }
+        assert { [string match "*infotest_global*" $info] }
+        assert { ![string match "*used_memory*" $info] }
+    }
+
+    test {module info one module} {
+        set info [r info INFOTEST]
+        # info all does not contain modules
+        assert { [string match "*Spanish*" $info] }
+        assert { ![string match "*used_memory*" $info] }
+        field $info infotest_global
+    } {-2}
+
+    test {module info one section} {
+        set info [r info INFOTEST_SPANISH]
+        assert { ![string match "*used_memory*" $info] }
+        assert { ![string match "*Italian*" $info] }
+        assert { ![string match "*infotest_global*" $info] }
+        field $info infotest_uno
+    } {one}
+
+    test {module info dict} {
+        set info [r info infotest_keyspace]
+        set keyspace [field $info infotest_db0]
+        set keys [scan [regexp -inline {keys\=([\d]*)} $keyspace] keys=%d]
+    } {3}
+
+    # TODO: test crash report.
+}