Merge pull request #11127 from zmstone/0622-refine-examples

0622 refine examples

.github/workflows/run_test_cases.yaml

@@ -88,6 +88,30 @@ jobs:
           name: source-${{ matrix.profile }}-${{ matrix.otp }}
           path: source.zip
 
+  check_examples:
+    needs:
+      - build-matrix
+      - prepare
+    runs-on: ${{ needs.build-matrix.outputs.runs-on }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include: ${{ fromJson(needs.build-matrix.outputs.prepare) }}
+    container: "ghcr.io/emqx/emqx-builder/${{ matrix.builder }}:${{ matrix.elixir }}-${{ matrix.otp }}-ubuntu22.04"
+    steps:
+      - uses: AutoModality/action-clean@v1
+      - uses: actions/download-artifact@v3
+        with:
+          name: source-${{ matrix.profile }}-${{ matrix.otp }}
+          path: .
+      - name: unzip source code
+        run: unzip -o -q source.zip
+      - name: check example config files
+        env:
+          PROFILE: ${{ matrix.profile }}
+        working-directory: source
+        run: ./scripts/test/check-example-configs.sh
+
   static_checks:
     needs:
       - build-matrix

apps/emqx/src/emqx_hocon.erl

@@ -24,7 +24,8 @@
     compact_errors/2,
     format_error/1,
     format_error/2,
-    make_schema/1
+    make_schema/1,
+    load_and_check/2
 ]).
 
 %% @doc Format hocon config field path to dot-separated string in iolist format.
@@ -135,3 +136,28 @@ compact_errors(SchemaModule, Error, Stacktrace) ->
         exception => Error,
         stacktrace => Stacktrace
     }}.
+
+%% @doc This is only used in static check scripts in the CI.
+-spec load_and_check(module(), filename:filename_all()) -> {ok, term()} | {error, any()}.
+load_and_check(SchemaModule, File) ->
+    try
+        do_load_and_check(SchemaModule, File)
+    catch
+        throw:Reason:Stacktrace ->
+            compact_errors(Reason, Stacktrace)
+    end.
+
+do_load_and_check(SchemaModule, File) ->
+    case hocon:load(File, #{format => map}) of
+        {ok, Conf} ->
+            Opts = #{atom_key => false, required => false},
+            %% here we check only the provided root keys
+            %% because the examples are all provided only with one (or maybe two) roots
+            %% and some roots have required fields.
+            RootKeys = maps:keys(Conf),
+            {ok, hocon_tconf:check_plain(SchemaModule, Conf, Opts, RootKeys)};
+        {error, {parse_error, Reason}} ->
+            {error, Reason};
+        {error, Reason} ->
+            {error, Reason}
+    end.

apps/emqx/src/emqx_schema.erl

@@ -3271,7 +3271,19 @@ tombstone() ->
 tombstone_map(Name, Type) ->
     %% marked_for_deletion must be the last member of the union
     %% because we need to first union member to populate the default values
-    map(Name, ?UNION([Type, ?TOMBSTONE_TYPE])).
+    map(
+        Name,
+        hoconsc:union(
+            fun
+                (all_union_members) ->
+                    [Type, ?TOMBSTONE_TYPE];
+                ({value, V}) when is_map(V) ->
+                    [Type];
+                ({value, _}) ->
+                    [?TOMBSTONE_TYPE]
+            end
+        )
+    ).
 
 %% inverse of mark_del_map
 get_tombstone_map_value_type(Schema) ->

apps/emqx_conf/src/emqx_conf_schema.erl

@@ -154,6 +154,8 @@ fields("cluster") ->
             sc(
                 node_array(),
                 #{
+                    %% This config is nerver needed (since 5.0.0)
+                    importance => ?IMPORTANCE_HIDDEN,
                     mapping => "mria.core_nodes",
                     default => [],
                     'readOnly' => true,

apps/emqx_conf/test/emqx_conf_schema_tests.erl

@@ -1,5 +1,17 @@
 %%--------------------------------------------------------------------
-%% Copyright (c) 2022-2023 EMQ Technologies Co., Ltd. All Rights Reserved.
+%% Copyright (c) 2023 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
 %%--------------------------------------------------------------------
 
 -module(emqx_conf_schema_tests).
@@ -488,3 +500,60 @@ check(Config) ->
         atom_key => false, required => false, format => map
     }),
     emqx_utils_maps:unsafe_atom_key_map(Conf).
+
+with_file(Path, Content, F) ->
+    ok = file:write_file(Path, Content),
+    try
+        F()
+    after
+        file:delete(Path)
+    end.
+
+load_and_check_test_() ->
+    [
+        {"non-existing file", fun() ->
+            File = "/tmp/nonexistingfilename.hocon",
+            ?assertEqual(
+                {error, {enoent, File}},
+                emqx_hocon:load_and_check(emqx_conf_schema, File)
+            )
+        end},
+        {"bad syntax", fun() ->
+            %% use abs path to match error return
+            File = "/tmp/emqx-conf-bad-syntax-test.hocon",
+            with_file(
+                File,
+                "{",
+                fun() ->
+                    ?assertMatch(
+                        {error, #{file := File}},
+                        emqx_hocon:load_and_check(emqx_conf_schema, File)
+                    )
+                end
+            )
+        end},
+        {"type-check failure", fun() ->
+            File = "emqx-conf-type-check-failure.hocon",
+            %% typecheck fail because cookie is required field
+            with_file(
+                File,
+                "node {}",
+                fun() ->
+                    ?assertMatch(
+                        {error, #{
+                            kind := validation_error,
+                            path := "node.cookie",
+                            reason := required_field
+                        }},
+                        emqx_hocon:load_and_check(emqx_conf_schema, File)
+                    )
+                end
+            )
+        end},
+        {"ok load", fun() ->
+            File = "emqx-conf-test-tmp-file-load-ok.hocon",
+            with_file(File, "plugins: {}", fun() ->
+                ?assertMatch({ok, _}, emqx_hocon:load_and_check(emqx_conf_schema, File))
+            end)
+        end}
+    ].

apps/emqx_prometheus/src/emqx_prometheus.app.src

@@ -2,7 +2,7 @@
 {application, emqx_prometheus, [
     {description, "Prometheus for EMQX"},
     % strict semver, bump manually!
-    {vsn, "5.0.12"},
+    {vsn, "5.0.13"},
     {modules, []},
     {registered, [emqx_prometheus_sup]},
     {applications, [kernel, stdlib, prometheus, emqx, emqx_management]},

apps/emqx_prometheus/src/emqx_prometheus_schema.erl

@@ -86,61 +86,67 @@ fields("prometheus") ->
             )},
         {vm_dist_collector,
             ?HOCON(
-                hoconsc:enum([enabled, disabled]),
+                hoconsc:enum([disabled, enabled]),
                 #{
-                    default => enabled,
+                    default => disabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(vm_dist_collector)
                 }
             )},
+        %% Mnesia metrics mainly using mnesia:system_info/1
         {mnesia_collector,
             ?HOCON(
                 hoconsc:enum([enabled, disabled]),
                 #{
                     default => enabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(mnesia_collector)
                 }
             )},
+        %% Collects Erlang VM metrics using erlang:statistics/1.
         {vm_statistics_collector,
             ?HOCON(
                 hoconsc:enum([enabled, disabled]),
                 #{
                     default => enabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(vm_statistics_collector)
                 }
             )},
+        %% Collects Erlang VM metrics using erlang:system_info/1.
         {vm_system_info_collector,
             ?HOCON(
                 hoconsc:enum([enabled, disabled]),
                 #{
                     default => enabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(vm_system_info_collector)
                 }
             )},
+        %% Collects information about memory dynamically allocated by the Erlang VM using erlang:memory/0,
+        %% it also provides basic (D)ETS statistics.
         {vm_memory_collector,
             ?HOCON(
                 hoconsc:enum([enabled, disabled]),
                 #{
                     default => enabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(vm_memory_collector)
                 }
             )},
+        %% Collects microstate accounting metrics using erlang:statistics(microstate_accounting).
         {vm_msacc_collector,
             ?HOCON(
                 hoconsc:enum([enabled, disabled]),
                 #{
                     default => enabled,
                     required => true,
-                    importance => ?IMPORTANCE_HIDDEN,
+                    importance => ?IMPORTANCE_LOW,
                     desc => ?DESC(vm_msacc_collector)
                 }
             )}

examples/README.md

@@ -1,16 +0,0 @@
-# Examples
-
-Here are examples of how to configure features In EMQX,  most of them can be used directly by copy-paste content into the `emqx.conf` file, others may need to be slightly modified to use, for example, you should change the listener port or HTTP URL to what you actually used.
-
-Although we have tried to show every configurable field in the example,
-you do not need to care about each one, since most of them already have default values and can be omitted in the configuration file.
-
-If you are confused about some fields, please refer to our documents, here are just some simple configuration examples with necessary descriptions.
-
-
-## Documentation
-
-The EMQX documentation is available at [www.emqx.io/docs/en/latest/](https://www.emqx.io/docs/en/latest/).
-
-The EMQX Enterprise documentation is available at [docs.emqx.com/en/](https://docs.emqx.com/en/).
-

examples/cluster-with-dns.conf.example

@@ -1,30 +0,0 @@
-##--------------------------------------------------------------------
-## Cluster in service discovery via DNS SRV records mode
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-cluster {
-    ## Human-friendly name of the EMQX cluster.
-    name = emqxcl
-
-    ## Service discovery method for the cluster nodes
-    discovery_strategy = dns
-
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
-    ## If true, the node will try to heal network partitions automatically
-    autoheal = true
-
-    dns {
-      ## The domain name from which to discover peer EMQX nodes' IP addresses
-      name = localhost
-
-      ## DNS record type
-      ## Type: enum: a | srv
-      record_type = a
-     }
- }

examples/cluster-with-etcd-ssl.conf.example

@@ -1,81 +0,0 @@
-##--------------------------------------------------------------------
-## Cluster in service discovery using 'etcd' service mode
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-cluster {
-    ## Human-friendly name of the EMQX cluster.
-    name = emqxcl
-
-    ## Service discovery method for the cluster nodes
-    discovery_strategy = etcd
-
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
-    ## If true, the node will try to heal network partitions automatically
-    autoheal = true
-
-    etcd {
-      ## List of endpoint URLs of the etcd cluster
-      server = "http://ur1,http://ur2"
-
-      ## Key prefix used for EMQX service discovery
-      prefix = emqxcl
-
-      ## Expiration time of the etcd key associated with the node.
-      node_ttl = 1m
-
-      ssl_options {
-          ## Trusted PEM format CA certificates bundle file
-          cacertfile = "data/certs/cacert.pem"
-
-          ## PEM format certificates chain file
-          certfile = "data/certs/cert.pem"
-
-          ## PEM format private key file
-          keyfile = "data/certs/key.pem"
-
-          ## Enable or disable peer verification
-          verify = verify_none ## use verify_peer to enable
-
-          ## if `verify' is ebabled, whit true, the connection fails if the client does not have a certificate to send
-          fail_if_no_peer_cert = false
-
-          ## Enable TLS session reuse
-          reuse_sessions = true
-
-          ## Maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path
-          depth = 10
-
-          ## Which versions are to be supported
-          versions = [tlsv1.3, tlsv1.2]
-
-          ## TLS cipher suite names
-          ## Note: By default, all available suites are supported, you do not need to set this
-          ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
-
-          ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
-          secure_renegotiate = true
-
-          ## Log level for SSL communication
-          ## Type: emergency | alert | critical | error | warning | notice | info | debug | none | all
-          log_level = notice
-
-          ## Hibernate the SSL process after idling for amount of time reducing its memory footprint
-          hibernate_after = 5s
-
-          ## Forces the cipher to be set based on the server-specified order instead of the client-specified order
-           honor_cipher_order = true
-
-          ##  Setting this to false to disable client-initiated renegotiation
-           client_renegotiation = true
-
-          ## Maximum time duration allowed for the handshake to complete
-           handshake_timeout = 15s
-      }
-    }
-}

examples/cluster-with-manual.conf.example

@@ -1,21 +0,0 @@
-##--------------------------------------------------------------------
-## Cluster in service discovery via manual join mode
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-cluster {
-    ## Human-friendly name of the EMQX cluster.
-    name = emqxcl
-
-    ## Service discovery method for the cluster nodes
-    discovery_strategy = manual
-
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
-    ## If true, the node will try to heal network partitions automatically
-    autoheal = true
- }

examples/cluster-with-static.conf.example

@@ -1,24 +0,0 @@
-##--------------------------------------------------------------------
-## Cluster in service discovery via static nodes mode
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-cluster {
-    ## Human-friendly name of the EMQX cluster.
-    name = emqxcl
-
-    ## Service discovery method for the cluster nodes
-    discovery_strategy = static
-
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
-    ## If true, the node will try to heal network partitions automatically
-    autoheal = true
-
-    ## List EMQX node names in the static cluster
-    static.seeds = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
- }

examples/conn_congestion.conf.example

@@ -1,15 +0,0 @@
-##--------------------------------------------------------------------
-## Connection Congestion
-##
-## Generating alarm when MQTT connection congested
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-conn_congestion {
-    ## Enable or disable connection congestion alarm
-    enable_alarm = true
-
-    ## Minimal time before clearing the alarm
-    min_alarm_sustain_duration = 1m
-}

examples/flapping_detect.conf.example

@@ -1,21 +0,0 @@
-##--------------------------------------------------------------------
-## Flapping Detect
-##
-## Ban the client when the times of connections exceed the limit in the time window
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-flapping_detect {
-    ## use false to disabled
-    enable = true
-
-    ## Time window for flapping detection
-    window_time = 1m
-
-    ## Maximum number of connects allowed for a MQTT Client in window_time
-    max_count = 15
-
-    ## How long the flapping clientid will be banned
-    ban_time = 5m
-}

examples/force_gc.conf.example

@@ -1,18 +0,0 @@
-##--------------------------------------------------------------------
-## Force garbage collection
-##
-## Force garbage collection in MQTT connection process after they process certain number of messages or bytes of data
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-force_gc {
-    ## set to false to disable this
-    enable = true
-
-    ## GC the process after this many received messages
-    count = 16000
-
-    ## GC the process after specified number of bytes have passed through
-    bytes = 16MB
-}

examples/force_shutdown.conf.example

@@ -1,19 +0,0 @@
-##--------------------------------------------------------------------
-## Force Shutdown
-##
-## Forced closing of the overloaded session
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-force_shutdown {
-    ## false to disable this
-    enable = true
-
-    ## Maximum mailbox size for each Erlang process
-    ## Note: Do not modify this unless you know what this is for
-    max_mailbox_size = 1000
-
-    ## Maximum heap size for each session process
-    max_heap_size = 32MB
-}

examples/node.conf.example

@@ -1,43 +0,0 @@
-##--------------------------------------------------------------------
-## Node
-##
-## configuring for current EMQX node
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-## Note: all fields in this section are immutable after EMQX started, and most of the time you only need to modify the value for the name and cookie.
-node {
-    ## The actions triggered when the alarm is activated
-    ## Type: Formatted String
-    ##   Format: any_name@any_domain or an_name@any_ip
-    ##   Note: Make sure the IP resolve from the domain is deterministic and unique and never change
-    name = "emqx@127.0.0.1"
-
-    ## Secret cookie is a random string that should be the same on all nodes in the given EMQX cluster, but unique per EMQX cluster
-    cookie = "Yzc0NGExM2RjYzYxYzM0YzQ5MWQ0NmI1NWM0MWRhMzY4NzgxYmFkMmI2MWJjZWQ5NTQzYTMxNjE1ODVmYmJmMyAgLQo="
-
-    ## Select a node role
-    ## Type:
-    ##   - core :: nodes provide durability of the data, and take care of writes
-    ##   - replicant :: nodes are ephemeral worker nodes
-    role = core
-
-    ## Maximum number of simultaneously existing processes for this Erlang system
-    ## Type: Range from 1024 to 134217727
-    process_limit = 2097152
-
-    ## Maximum number of simultaneously existing ports for this Erlang system
-    ## Type: Range from 1024 to 134217727
-    max_ports = 1048576
-
-    ## Erlang's distribution buffer busy limit in kilobytes
-    ## Type: Range from 1 to 2097152
-    dist_buffer_size = 8192
-
-    ## Path to the persistent data directory
-    data_dir = "var/emqx/data"
-
-    ## Type: Periodic garbage collection interval
-    global_gc_interval = 15m
-}

examples/prometheus.conf.example

@@ -1,28 +0,0 @@
-##--------------------------------------------------------------------
-## Prometheus
-##
-## Settings for reporting metrics to Prometheus
-##--------------------------------------------------------------------
-
-prometheus {
-    ## URL of Prometheus server
-    push_gateway_server = "http://127.0.0.1:9091"
-
-    ## Data reporting interval
-    interval = 15s
-
-    ## A HTTP Headers when pushing to Push Gateway.
-    headers = {
-        Authorization = "some-authz-tokens",
-        Connection = "keep-alive"
-    }
-
-    ## Job Name that is pushed to the Push Gateway.
-    ## Available variable:
-    ## - ${name}: Name of EMQX node
-    ## - ${host}: Host name of EMQX node
-    job_name = "${name}/instance/${name}~${host}"
-
-    ## set to false to enable this
-    enable = true
-}

mix.exs

@@ -539,11 +539,24 @@ defmodule EMQXUmbrella.MixProject do
     profile = System.get_env("MIX_ENV")
 
     File.cp_r!(
-      "examples",
+      "rel/config/examples",
       Path.join(etc, "examples"),
       force: overwrite?
     )
 
+    # copy /rel/config/ee-examples if profile is enterprise
+    case profile do
+      "emqx-enterprise" ->
+        File.cp_r!(
+          "rel/config/ee-examples",
+          Path.join(etc, "examples"),
+          force: overwrite?
+        )
+
+      _ ->
+        :ok
+    end
+
     # this is required by the produced escript / nodetool
     Mix.Generator.copy_file(
       Path.join(release.version_path, "start_clean.boot"),

rebar.config.erl

@@ -521,12 +521,12 @@ relx_overlay(ReleaseType, Edition) ->
         {copy, "bin/nodetool", "bin/nodetool-{{release_version}}"}
     ] ++ etc_overlay(ReleaseType, Edition).
 
-etc_overlay(ReleaseType, _Edition) ->
+etc_overlay(ReleaseType, Edition) ->
     Templates = emqx_etc_overlay(ReleaseType),
     [
         {mkdir, "etc/"},
-        {copy, "{{base_dir}}/lib/emqx/etc/certs", "etc/"},
+        {copy, "{{base_dir}}/lib/emqx/etc/certs", "etc/"}
-        {copy, "examples", "etc/"}
+        | copy_examples(Edition)
     ] ++
         lists:map(
             fun
@@ -536,6 +536,14 @@ etc_overlay(ReleaseType, _Edition) ->
             Templates
         ).
 
+copy_examples(ce) ->
+    [{copy, "rel/config/examples", "etc/"}];
+copy_examples(ee) ->
+    [
+        {copy, "rel/config/examples", "etc/"},
+        {copy, "rel/config/ee-examples/*", "etc/examples/"}
+    ].
+
 emqx_etc_overlay(ReleaseType) ->
     emqx_etc_overlay_per_rel(ReleaseType) ++
         emqx_etc_overlay().

rel/config/ee-examples/file_transfer-with-local-exporter.conf.example

@@ -1,12 +1,6 @@
-##--------------------------------------------------------------------
+## File Transfer over MQTT exporting files to local file system
-## File Transfer
 ##
-## Enables the File Transfer over MQTT feature
+## NOTE: This configuration is only applicable in EMQX Enterprise edition 5.1 or later.
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-## Note: This configuration only works for the EMQX Enterprise version
 
 file_transfer {
     ## Enable the File Transfer feature

rel/config/ee-examples/file_transfer-with-s3-exporter.conf.example

@@ -1,12 +1,7 @@
-##--------------------------------------------------------------------
+## File Transfer over MQTT
-## File Transfer
 ##
 ## Enables the File Transfer over MQTT feature
-##--------------------------------------------------------------------
+## Note: This configuration is only applicable for EMQX Enterprise edition 5.1 or later.
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-## Note: This configuration only works for the EMQX Enterprise version
 
 file_transfer {
     ## Enable the File Transfer feature
@@ -62,9 +57,6 @@ file_transfer {
 
                     ## Timeout for connection attempts
                     connect_timeout = 15s
-
-                    ## Attempt to talk through IPv6 first
-                    ipv6_probe = true
                }
            }
         }

rel/config/ee-examples/license.conf.example

@@ -1,12 +1,6 @@
-##--------------------------------------------------------------------
+## EMQX Enterprise License
-## License
-##
-## Defines the EMQX Enterprise license
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## Note: This configuration only works for the EMQX Enterprise version
+## NOTE: This configuration is only applicable for the EMQX Enterprise eidtion
 
 license {
     ## License Key

rel/config/examples/README.md

@@ -0,0 +1,24 @@
+# Examples
+
+Here are examples of how to configure EMQX.
+The main purpose of the examples are to serve as a reference for configuration layout and syntax, but not a guide to how to configure EMQX.
+For more information about EMQX configuration, please refer to EMQX documentation (links below).
+
+There are two ways to extend the configuration of EMQX:
+
+* By adding the configs to `emqx.conf` file.
+* By adding the configs to a new file and include it in `emqx.conf` file. For example, add `include "mylisteners.conf"` to `emqx.conf` file and add the listeners to `mylisteners.conf`.
+
+EMQX configuration consists of two parts: static configs and dynamic configs.
+
+* Configs loaded from `emqx.conf` (and included files) are static configs.
+* Configs added or updated from the dashboard or CLI are dynamic configs which are synced to all nodes in the cluster and stored in the data directory on each node.
+
+It is important to note that static configs are loaded when EMQX starts and overlays on top of the dynamic configs,
+to avoid confusion, it is highly recommended NOT to use the same config name for both static and dynamic configs.
+
+## Documentation
+
+The EMQX documentation is available at [www.emqx.io/docs/en/latest/](https://www.emqx.io/docs/en/latest/).
+
+The EMQX Enterprise documentation is available at [docs.emqx.com/en/](https://docs.emqx.com/en/).

rel/config/examples/alarm.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## Alarm
-##
-## Configuring how to handle the alarms generated from sysmon.*.conf.example
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 alarm {
     ## The actions triggered when the alarm is activated

rel/config/examples/cluster-with-dns.conf.example

@@ -0,0 +1,21 @@
+## Cluster discovery via DNS resolution
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = dns
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    dns {
+      ## The domain name from which to discover peer EMQX nodes' IP addresses
+      name = localhost
+
+      ## DNS record type
+      ## Type: enum: a | srv
+      record_type = a
+     }
+ }

rel/config/examples/cluster-with-etcd-ssl.conf.example

@@ -0,0 +1,37 @@
+## Cluster discovery using 'etcd'
+## connect to etcd over TLS
+
+cluster {
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = etcd
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    etcd {
+      ## List of endpoint URLs of the etcd cluster
+      server = "http://ur1,http://ur2"
+
+      ## Key prefix used for EMQX service discovery
+      prefix = emqxcl
+
+      ## Expiration time of the etcd key associated with the node.
+      node_ttl = 1m
+
+      ssl_options {
+          ## Trusted PEM format CA certificates bundle file
+          cacertfile = "${EMQX_ETC_DIR}/certs/etcd-cacert.pem"
+
+          ## PEM format certificates chain file
+          certfile = "${EMQX_ETC_DIR}/certs/etcd-client-cert.pem"
+
+          ## PEM format private key file
+          keyfile = "${EMQX_ETC_DIR}/certs/etcd-client-key.pem"
+
+          ## Enable or disable peer verification
+          verify = verify_none ## use verify_peer to enable
+      }
+    }
+}

rel/config/examples/cluster-with-etcd.conf.example

@@ -1,10 +1,5 @@
-##--------------------------------------------------------------------
+## Cluster discovery using 'etcd' service
-## Cluster in service discovery using 'etcd' service mode
+## Connect to etcd over plain TCP (not TLS)
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 cluster {
     ## Human-friendly name of the EMQX cluster.
@@ -13,9 +8,6 @@ cluster {
     ## Service discovery method for the cluster nodes
     discovery_strategy = etcd
 
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
     ## If true, the node will try to heal network partitions automatically
     autoheal = true
 

rel/config/examples/cluster-with-k8s.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
+## Cluster discovery via Kubernetes API server mode
-## Cluster in service discovery via Kubernetes API server mode
-##
-## Configs to instruct how individual nodes can discover each other
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 cluster {
     ## Human-friendly name of the EMQX cluster.
@@ -13,9 +7,6 @@ cluster {
     ## Service discovery method for the cluster nodes
     discovery_strategy = k8s
 
-    ## List of core nodes that the replicant will connect to
-    core_nodes = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
-
     ## If true, the node will try to heal network partitions automatically
     autoheal = true
 

rel/config/examples/cluster-with-manual.conf.example

@@ -0,0 +1,12 @@
+## Cluster discovery via `emqx ctl cluster` command
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = manual
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+ }

rel/config/examples/cluster-with-static.conf.example

@@ -0,0 +1,15 @@
+## Cluster discovery via static seed nodes
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = static
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    ## List EMQX node names in the static cluster
+    static.seeds = ["emqx1@192.168.0.1", "emqx2@192.168.0.2"]
+ }

rel/config/examples/conn_congestion.conf.example

@@ -0,0 +1,11 @@
+## Connection Congestion
+##
+## Emit alarms when MQTT connection congested
+
+conn_congestion {
+    ## Enable or disable connection congestion alarm
+    enable_alarm = true
+
+    ## Minimal time before clearing the alarm
+    min_alarm_sustain_duration = 1m
+}

rel/config/examples/dashboard-with-http.conf.example

@@ -1,10 +1,6 @@
-##--------------------------------------------------------------------
+## Dashboard on HTTP
-## Dashboard with HTTP Listener
 ##
-## Configuration for EMQX dashboard
+## Configure HTTP for EMQX dashboard
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 dashboard {
     ## JWT token expiration time

rel/config/examples/dashboard-with-https.conf.example

@@ -1,10 +1,6 @@
-##--------------------------------------------------------------------
+## Dashboard on HTTPS
-## Dashboard with HTTPS Listener
 ##
-## Configuration for EMQX dashboard
+## Configure HTTPS for EMQX dashboard
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 dashboard {
     ## JWT token expiration time

rel/config/examples/exhook.conf.example

@@ -1,8 +1,6 @@
-##--------------------------------------------------------------------
 ## gRPC Hook Extension
 ##
-## Allows users to process EMQX Hooks using other programming languages
+## Allows users to provide hook callbacks over gRPC for EMQX message lifecycle events.
-##--------------------------------------------------------------------
 
 exhook.servers = [
     {

rel/config/examples/flapping_detect.conf.example

@@ -0,0 +1,17 @@
+## Flapping Detect
+##
+## Ban the client when the times of connections exceed the limit in the configured time window
+
+flapping_detect {
+    ## use 'true' to enable this feature
+    enable = false
+
+    ## Time window for flapping detection
+    window_time = 1m
+
+    ## Maximum number of connects allowed for a MQTT Client in window_time
+    max_count = 15
+
+    ## How long the flapping clientid will be banned
+    ban_time = 5m
+}

rel/config/examples/force_gc.conf.example

@@ -0,0 +1,12 @@
+## Force Elrang VM garbage collection
+
+force_gc {
+    ## set 'false' to disable this feature
+    enable = true
+
+    ## GC the process after this many received messages
+    count = 16000
+
+    ## GC the process after specified number of bytes have passed through
+    bytes = 16MB
+}

rel/config/examples/force_shutdown.conf.example

@@ -0,0 +1,15 @@
+## Force Shutdown
+##
+## Forced shutdown MQTT clients for overload protection
+
+force_shutdown {
+    ## set 'false' to disable force shutdown feature
+    enable = true
+
+    ## Maximum mailbox size for each Erlang process
+    ## Note: Do not modify this unless you know what this is for
+    max_mailbox_size = 1000
+
+    ## Maximum heap size for each session process
+    max_heap_size = 32MB
+}

rel/config/examples/gateway.exproto.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## Gateway Exproto
-##
-## Add an Exproto gateway
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 gateway.exproto {
 

rel/config/examples/gateway.lwm2m.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## Gateway LwM2M
-##
-## Add a LwM2M gateway
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 gateway.lwm2m {
 

rel/config/examples/gateway.mqttsn.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## Gateway MQTT-SN
-##
-## Add a MQTT-SN gateway
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 gateway.mqttsn {
 

rel/config/examples/gateway.stomp.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## Gateway STOMP
-##
-## Add STOMP CoAP gateway
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 gateway.stomp {
 

rel/config/examples/listeners.quic.conf.example

@@ -1,13 +1,6 @@
-##--------------------------------------------------------------------
+## MQTT over QUIC Listener
-## QUIC Listener
-##
-## Add a QUIC Listener
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## Note: Modifying the 'quicname' to what you need
+listeners.quic.my_quick_listener_name {
-listeners.quic.quicname {
     ## Port or Address to listen on, 0 means disable
     bind = 14567 ## or with an IP, e.g. "127.0.0.1:14567"
 
@@ -28,8 +21,8 @@ listeners.quic.quicname {
     ## Type: infinity | Integer
     max_connections = infinity
 
-    ## TLS cipher suite names
+    ## TLS v1.3 exclusive cipher suite names
-    ciphers = ["TLS_AES_256_GCM_SHA384", "TLS_AES_128_GCM_SHA256", "TLS_CHACHA20_POLY1305_SHA256"]
+    ciphers = "TLS_AES_256_GCM_SHA384,TLS_AES_128_GCM_SHA256,TLS_CHACHA20_POLY1305_SHA256"
 
     ssl_options {
         ## Trusted PEM format CA certificates bundle file

rel/config/examples/listeners.ssl.conf.example

@@ -1,16 +1,6 @@
-##--------------------------------------------------------------------
+## MQTT over TLS(SSL) Listener
-## SSL Listener
-##
-## Add a SSL Listener
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## The SSL listener also supports all the fields listed in listeners.tcp.conf.example
+listeners.ssl.my_ssl_listener_name {
-## only the SSL-specific fields are shown here
-
-## Note: Modifying the 'sslname' to what you need
-listeners.ssl.sslname {
     ## Port or Address to listen on, 0 means disable
     bind = 8883 ## or with an IP e.g. "127.0.0.1:8883"
     enabled = true
@@ -33,13 +23,13 @@ listeners.ssl.sslname {
     }
     ssl_options {
         ## Trusted PEM format CA certificates bundle file
-        cacertfile = "data/certs/cacert.pem"
+        cacertfile = "${EMQX_ETC_DIR}/certs/cacert.pem"
 
         ## PEM format certificates chain file
-        certfile = "data/certs/cert.pem"
+        certfile = "${EMQX_ETC_DIR}/certs/cert.pem"
 
         ## PEM format private key file
-        keyfile = "data/certs/key.pem"
+        keyfile = "${EMQX_ETC_DIR}/certs/key.pem"
 
         ## Enable or disable peer verification
         verify = verify_none  ## use verify_peer to enable
@@ -58,7 +48,7 @@ listeners.ssl.sslname {
 
         ## TLS cipher suite names
         ## Note: By default, all available suites are supported, you do not need to set this
-        ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+        ciphers = "TLS_AES_256_GCM_SHA384,TLS_AES_128_GCM_SHA256,ECDHE-RSA-AES256-GCM-SHA384"
 
         ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
         secure_renegotiate = true
@@ -82,7 +72,7 @@ listeners.ssl.sslname {
         ocsp {
              enable_ocsp_stapling = false
              responder_url = "http://ocsp.example.com"
-             issuer_pem = true
+             issuer_pem = "${EMQX_ETC_DIR}/certs/ocsp-issuer-cert.pem"
              refresh_http_timeout = 15s
              refresh_interval = 5m
         }

rel/config/examples/listeners.tcp.conf.example

@@ -1,13 +1,6 @@
-##--------------------------------------------------------------------
+## MQTT over TCP Listener
-## TCP Listener
-##
-## Add a TCP Listener
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## Note: Modifying the 'tcpname' to what you need
+listeners.tcp.my_tcp_listener_name {
-listeners.tcp.tcpname {
     ## Port or Address to listen on, 0 means disable
     bind = 1883 ## or with an IP e.g. "127.0.0.1:1883"
 

rel/config/examples/listeners.ws.conf.example

@@ -1,16 +1,6 @@
-##--------------------------------------------------------------------
+## MQTT over WebSocket (HTTP) Listener
-## WebSocket Listener
-##
-## Add a WebSocket Listener
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## The WebSocket listener supports all the fields listed in listeners.tcp.conf.example
+listeners.ws.my_ws_listener_name {
-## only the WebSocket-specific fields are shown here
-
-## Note: Modifying the 'wsname' to what you need
-listeners.ws.wsname {
     ## Port or Address to listen on, 0 means disable
     bind = "0.0.0.0:8083" # or just a port number, e.g. 8083
     enabled = true

rel/config/examples/listeners.wss.conf.example

@@ -1,16 +1,6 @@
-##--------------------------------------------------------------------
+## MQTT over Secured Websocket (HTTPS) Listener
-## WSS Listener
-##
-## Add a WSS Listener
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## The WSS listener supports all the fields listed in listeners.ws.conf.example
+listeners.wss.my_wss_listener_name = {
-## only the WSS-specific fields are shown here
-
-## Note: Modifying the 'wssname' to what you need
-listeners.wss.wssname {
     ## Port or Address to listen on, 0 means disable
     bind = 8084 ## or with an IP, e.g. "127.0.0.1:8084"
     enabled = true
@@ -76,11 +66,11 @@ listeners.wss.wssname {
         depth = 10
 
         ## Which versions are to be supported
-        versions = [tlsv1.3, tlsv1.2]
+        versions = ["tlsv1.3", "tlsv1.2"]
 
         ## TLS cipher suite names
         ## Note: By default, all available suites are supported, you do not need to set this
-        ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+        ciphers = "TLS_AES_256_GCM_SHA384,TLS_AES_128_GCM_SHA256,ECDHE-RSA-AES256-GCM-SHA384"
 
         ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
         secure_renegotiate = true

rel/config/examples/log.console.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
+## Log to console
-## Log
-##
-## Configure the log output location, log level, log file storage path, and parameters
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 log.console {
     ## set true to enable this

rel/config/examples/log.file.conf.example

@@ -1,21 +1,14 @@
-##--------------------------------------------------------------------
+## Log to file
-## Log
-##
-## Configure the log output location, log level, log file storage path, and parameters
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
-## The default-enabled log handler can use all the above fields listed fields
 log.file {
-    ## use false to disable this
+    ## Enable file log handler
     enable = true
 
     ## Log level
     ## Type: debug | info | notice | warning | error | critical | alert | emergency
     level = warning
 
-    ## Log formatter, text for free text, and json for structured logging
+    ## Log formatter, text for free text, and json for more structured logging
     ## Type: text | json
     formatter = text
 

rel/config/examples/mqtt.conf.example

@@ -1,10 +1,5 @@
-##--------------------------------------------------------------------
+## MQTT protocol related settings
-## MQTT
+## Settings in this section is applied globally to all MQTT connections/sessions in this node
-##
-##  MQTT configuration
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 mqtt {
     ## After the TCP connection is established,

rel/config/examples/node.conf.example

@@ -0,0 +1,39 @@
+## EMQX Node
+
+## Note: all fields in this section are immutable after EMQX started, and most of the time you only need to modify the value for the name and cookie.
+node {
+    ## The actions triggered when the alarm is activated
+    ## Type: Formatted String
+    ##   Format: any_name@any_domain or an_name@any_ip
+    ##   Note: Make sure the IP resolve from the domain is deterministic and unique and never change
+    name = "emqx@127.0.0.1"
+
+    ## Secret cookie is a random string that should be the same on all nodes in the cluster, but unique per EMQX cluster
+    cookie = "Yzc0NGExM2Rj"
+
+    ## Select a node role
+    ## Possible values:
+    ##   - core: This is a core node which provides durability of the client states, and takes care of writes
+    ##   - replicant: This is a stateless worker node
+    role = core
+
+    ## Maximum number of simultaneously existing processes for this Erlang system
+    process_limit = 2097152
+
+    ## Maximum number of simultaneously open files and sockets for this Erlang system
+    max_ports = 1048576
+
+    ## Erlang's distribution buffer busy limit in kilobytes.
+    ## Range from 1 to 2097152
+    dist_buffer_size = 8192
+
+    ## NOTE: keep this the same for all nodes in the cluster.
+    ## Path to the persistent data directory.
+    ## This config is pre-filled when the EMQX distribution package is built.
+    ## You are advised to use the default value.
+    data_dir = "data" # when running a zip package or in docker container
+    #data_dir = "/var/lib/emqx" # when installed from deb/rpm packages
+
+    ## Type: Periodic garbage collection interval
+    global_gc_interval = 15m
+}

rel/config/examples/plugins.conf.example

@@ -1,12 +1,5 @@
-##--------------------------------------------------------------------
+## Plugin management
-## Plugin
+plugins {
-##
-## Manage EMQX plugins
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
-
-plugin {
     ## Plugins declaration
     ## Note: The plugins are started in the defined order
     states = [

rel/config/examples/prometheus-pushgateway.conf.example

@@ -0,0 +1,28 @@
+## Prometheus push-gateway integration
+
+## EMQX's Prometheus scraping endpoint is enabled by default without authentication.
+## e.g. curl -f "127.0.0.1:18083/api/v5/prometheus/stats"
+## If you want to use push-gateway
+
+prometheus {
+    ## Set to true to make EMQX send metrics to push-gateway
+    enable = false
+
+    ## URL of push-gateway server
+    push_gateway_server = "http://127.0.0.1:9091"
+
+    ## Data push interval
+    interval = 15s
+
+    ## A HTTP Headers when pushing to Push-gateway
+    headers = {
+        Authorization = "some-authz-tokens",
+        Connection = "keep-alive"
+    }
+
+    ## Job Name that is pushed to the Push-gateway
+    ## Available variable:
+    ## - ${name}: Name of EMQX node
+    ## - ${host}: Host name of EMQX node
+    job_name = "${name}/instance/${name}~${host}"
+}

rel/config/examples/prometheus.conf.example

@@ -0,0 +1,10 @@
+## Prometheus
+
+## EMQX's Prometheus scraping endpoint is enabled by default without authentication.
+## And there is no way to turn it off.
+## You can inspect it with a curl command: curl -f "127.0.0.1:18083/api/v5/prometheus/stats"
+
+prometheus {
+    # turn off this expensive collector
+    vm_dist_collector = disabled
+}

rel/config/examples/psk_authentication.conf.example

@@ -1,13 +1,7 @@
-##--------------------------------------------------------------------
 ## Pre-Shared Keys authentication
-##
-## Config to enable TLS-PSK authentication
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 psk_authentication {
-    ## set to false to disable
+    ## Set to false to disable
     enable = true
 
     ## If init_file is specified, EMQX will import PSKs from the file into the built-in database at startup for use by the runtime

rel/config/examples/retainer.conf.example

@@ -3,20 +3,12 @@
 ##
 ## Configuration related to handling PUBLISH packets with a retain flag set to 1
 ##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 retainer {
-    ## set to false to disable this
+    ## set to false to disable retainer
     enable = true
 
-    ## Message retention time. 0 means message will never be expired
+    ## Maximum message size allowed
-    msg_expiry_interval = 0s
-
-    ## Periodic interval for cleaning up expired messages. Never clear if the value is 0
-    msg_clear_interval = 0s
-
-    ## Maximum retained message size
     max_payload_size = 1MB
 
     ## When the retained flag of the PUBLISH message is set and Payload is empty, whether to continue to publish the message
@@ -27,10 +19,10 @@ retainer {
 
     ## Retained messages store backend
     backend {
-      ## Backend type
+      ## Built-in database (Mnesia)
       type = built_in_database
 
-      ## Specifies whether the messages are stored in RAM or persisted on disc
+      ## Specifies whether the messages are stored in RAM or persisted on disk
       ## Type: enum: ram | disc
       storage_type = ram
 

rel/config/examples/sys_topics.conf.example

@@ -1,10 +1,5 @@
-##--------------------------------------------------------------------
 ## System Topic
-##
 ## Publishing client lifecycle events to "$SYS" topics
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 sys_topics {
     ## Time interval of publishing `$SYS` messages

rel/config/examples/sysmon.os.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
+## System Monitoring of the host machine
-## System Monitoring For System
-##
-## System monitoring and introspection
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 sysmon.os {
     ## Time interval for the periodic CPU check
@@ -17,9 +11,9 @@ sysmon.os {
     cpu_low_watermark = 60%
 
     ## Time interval for the periodic memory check
-    ## Type:
+    ## Possible values:
-    ##   - disabled :: Never check
+    ##   disabled: Never check
-    ##   - Time Duration :: The time period
+    ##   Duration: Check every Duration 
     mem_check_interval = 60s
 
     ## For how much system memory can be allocated before the corresponding alarm is raised

rel/config/examples/sysmon.vm.conf.example

@@ -1,10 +1,4 @@
-##--------------------------------------------------------------------
 ## System Monitoring For Erlang VM
-##
-## System monitoring and introspection
-##--------------------------------------------------------------------
-## Note: This is an example of how to configure this feature
-##       you should copy and paste the below data into the emqx.conf for working
 
 sysmon.vm {
     ## Time interval for the periodic process limit check
@@ -25,7 +19,7 @@ sysmon.vm {
     ## Generating an alarm is generated when the Erlang VM detect a task scheduled for too long
     ## Type:
     ##   - disabled :: Never alarm
-    ##   - Time During :: The maximum schedule time for generating an alarm
+    ##   - Duration:: The maximum schedule time for generating an alarm
     long_schedule = 240ms
 
     ## Generating an alarm when an Erlang process consumed a large amount of memory for its heap space

rel/i18n/emqx_conf_schema.hocon

@@ -135,7 +135,7 @@ log_overload_kill_restart_after.label:
 """Handler Restart Timer"""
 
 log_file_handler_max_size.desc:
-"""This parameter controls log file rotation. The value `infinity` means the log file will grow indefinitely, otherwise the log file will be rotated once it reaches `max_size` in bytes."""
+"""This parameter controls log file rotation. The value `infinity` means the log file will grow indefinitely, otherwise the log file will be rotated once it reaches `rotation_size` in bytes."""
 
 log_file_handler_max_size.label:
 """Rotation Size"""
@@ -389,17 +389,6 @@ cluster_mcast_ttl.desc:
 cluster_mcast_ttl.label:
 """Cluster Multicast TTL"""
 
-db_core_nodes.desc:
-"""List of core nodes that the replicant will connect to.<br/>
-Note: this parameter only takes effect when the <code>backend</code> is set
-to <code>rlog</code> and the <code>role</code> is set to <code>replicant</code>.<br/>
-This value needs to be defined for manual or static cluster discovery mechanisms.<br/>
-If an automatic cluster discovery mechanism is being used (such as <code>etcd</code>),
-there is no need to set this value."""
-
-db_core_nodes.label:
-"""Db Core Node"""
-
 log_file_handler_file.desc:
 """Name the log file."""
 
@@ -514,15 +503,13 @@ cluster_autoclean.label:
 
 process_limit.desc:
 """Maximum number of simultaneously existing processes for this Erlang system.
-The actual maximum chosen may be much larger than the Number passed.
 For more information, see: https://www.erlang.org/doc/man/erl.html"""
 
 process_limit.label:
 """Erlang Process Limit"""
 
 max_ports.desc:
-"""Maximum number of simultaneously existing ports for this Erlang system.
+"""Maximum number of simultaneously open files and sockets for this Erlang system.
-The actual maximum chosen may be much larger than the Number passed.
 For more information, see: https://www.erlang.org/doc/man/erl.html"""
 
 max_ports.label:

rel/i18n/emqx_prometheus_schema.hocon

@@ -18,30 +18,32 @@ For example, when the EMQX node name is <code>emqx@127.0.0.1</code> then the <co
 Default value is: <code>${name}/instance/${name}~${host}</code>"""
 
 mnesia_collector.desc:
-"""Enable or disable Mnesia collector, collects Mnesia metrics mainly using mnesia:system_info/1 ."""
+"""Enable or disable Mnesia metrics collector"""
 
 prometheus.desc:
-"""Settings for reporting metrics to Prometheus"""
+"""EMQX's Prometheus scraping endpoint is enabled by default without authentication.
+You can inspect it with a `curl` command like this: `curl -f "127.0.0.1:18083/api/v5/prometheus/stats"`<br/>
+The 'enable' flag is used to turn on and off for the push-gateway integration."""
 
 prometheus.label:
 """Prometheus"""
 
 push_gateway_server.desc:
-"""URL of Prometheus server"""
+"""URL of Prometheus server. Pushgateway is optional, should not be configured if prometheus is to scrape EMQX."""
 
 vm_dist_collector.desc:
 """Enable or disable VM distribution collector, collects information about the sockets and processes involved in the Erlang distribution mechanism."""
 
 vm_memory_collector.desc:
-"""Enable or disable VM memory collector, collects information about memory dynamically allocated by the Erlang emulator using erlang:memory/0 , also provides basic (D)ETS statistics ."""
+"""Enable or disable VM memory metrics collector."""
 
 vm_msacc_collector.desc:
-"""Enable or disable VM msacc collector, collects microstate accounting metrics using erlang:statistics(microstate_accounting) ."""
+"""Enable or disable VM microstate accounting metrics collector."""
 
 vm_statistics_collector.desc:
-"""Enable or disable VM statistics collector, collects Erlang VM metrics using erlang:statistics/1 ."""
+"""Enable or disable VM statistics collector."""
 
 vm_system_info_collector.desc:
-"""Enable or disable VM system info collector, collects Erlang VM metrics using erlang:system_info/1 ."""
+"""Enable or disable VM system info collector."""
 
 }

rel/i18n/emqx_retainer_schema.hocon

@@ -34,11 +34,11 @@ mnesia_config_type.desc:
 """Backend type."""
 
 msg_clear_interval.desc:
-"""Periodic interval for cleaning up expired messages.
+"""Interval for EMQX to scan expired messages and delete them. Never scan if the value is 0."""
-Never clear if the value is 0."""
 
 msg_expiry_interval.desc:
-"""Message retention time. 0 means message will never be expired."""
+"""Message retention time. This config is only applicable for messages without the Message Expiry Interval message property.
+0 means message will never expire."""
 
 stop_publish_clear_msg.desc:
 """When the retained flag of the `PUBLISH` message is set and Payload is empty,

scripts/test/check-example-configs.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+PROJ_DIR="$(git rev-parse --show-toplevel)"
+
+PROFILE="${PROFILE:-emqx}"
+DIR_NAME='examples'
+SCHEMA_MOD='emqx_conf_schema'
+if [ "${PROFILE}" = 'emqx-enterprise' ]; then
+    DIR_NAME='ee-examples'
+    SCHEMA_MOD='emqx_enterprise_schema'
+fi
+
+IFS=$'\n' read -r -d '' -a FILES < <(find "${PROJ_DIR}/rel/config/${DIR_NAME}" -name "*.example" 2>/dev/null | sort && printf '\0')
+
+prepare_erl_libs() {
+    local libs_dir="$1"
+    local erl_libs="${ERL_LIBS:-}"
+    local sep=':'
+    for app in "${libs_dir}"/*; do
+        if [ -d "${app}/ebin" ]; then
+            if [ -n "$erl_libs" ]; then
+                erl_libs="${erl_libs}${sep}${app}"
+            else
+                erl_libs="${app}"
+            fi
+        fi
+    done
+    export ERL_LIBS="$erl_libs"
+}
+
+# This is needed when checking schema
+export EMQX_ETC_DIR="${PROJ_DIR}/apps/emqx/etc"
+
+prepare_erl_libs "_build/$PROFILE/lib"
+
+check_file() {
+    local file="$1"
+    erl -noshell -eval \
+        "File=\"$file\",
+         case emqx_hocon:load_and_check($SCHEMA_MOD, File) of
+            {ok, _} ->
+                io:format(\"check_example_config_ok: ~s~n\", [File]),
+                halt(0);
+            {error, Reason} ->
+                io:format(\"failed_to_check_example_config: ~s~n~p~n\", [File, Reason]),
+                halt(1)
+        end."
+}
+
+for file in "${FILES[@]}"; do
+    check_file "$file"
+done