Skip to content

Latest commit

 

History

History
939 lines (766 loc) · 34.1 KB

UPGRADE.md

File metadata and controls

939 lines (766 loc) · 34.1 KB
Raw

This document guides you through the process of upgrading Kong. First, check if a section named "Upgrade to Kong x.x.x" exists, with x.x.x being the version you are planning to upgrade to. If such a section does not exist, the upgrade you want to perform does not have any particular instructions, and you can simply consult the Suggested upgrade path.

Suggested upgrade path

Unless indicated otherwise in one of the upgrade paths of this document, it is possible to upgrade Kong without downtime:

Assuming that Kong is already running on your system, acquire the latest version from any of the available installation methods and proceed to install it, overriding your previous installation.

If you are planning to make modifications to your configuration, this is a good time to do so.

Then, run migration to upgrade your database schema:

$ kong migrations up [-c configuration_file]

If the command is successful, and no migration ran (no output), then you only have to reload Kong:

$ kong reload [-c configuration_file]

Reminder: kong reload leverages the Nginx reload signal that seamlessly starts new workers, which take over from old workers before those old workers are terminated. In this way, Kong will serve new requests via the new configuration, without dropping existing in-flight connections.

Upgrade to 0.11.x

Along with the usual database migrations shipped with our major releases, this particular release introduces quite a few changes in behavior and, most notably, the enforced manual migrations process and the removal of the Serf dependency for cache invalidation between Kong nodes of the same cluster.

This document will only highlight the breaking changes that you need to be aware of, and describe a recommended upgrade path. We recommend that you consult the full 0.11.0 Changelog for a complete list of changes and new features.

Breaking changes

Configuration
  • Several updates were made to the Nginx configuration template. If you are using a custom template, you must apply those modifications. See below for a list of changes to apply.
Migrations & Deployment
  • Migrations are not executed automatically by kong start anymore. Migrations are now a manual process, which must be executed via the kong migrations command. In practice, this means that you have to run kong migrations up [-c kong.conf] in one of your nodes before starting your Kong nodes. This command should be run from a single node/container to avoid several nodes running migrations concurrently and potentially corrupting your database. Once the migrations are up-to-date, it is considered safe to start multiple Kong nodes concurrently.
  • Serf is not a dependency anymore. Kong nodes now handle cache invalidation events via a built-in database polling mechanism. See the new "Datastore Cache" section of the configuration file which contains 3 new documented properties: db_update_frequency, db_update_propagation, and db_cache_ttl. If you are using Cassandra, you should pay a particular attention to the db_update_propagation setting, as you should not use the default value of 0.

Note for Docker users: Because of the aforementioned breaking change, if you are running Kong with Docker, you will now need to run the migrations from a single, ephemeral container. You can follow the Docker installation instructions (see "2. Prepare your database") for more details about this process.

Core
  • Kong now requires OpenResty 1.11.2.4. OpenResty's LuaJIT can now be built with Lua 5.2 compatibility, and the --without-luajit-lua52 flag can be omitted.
  • While Kong now correctly proxies downstream X-Forwarded-* headers, the introduction of the new trusted_ips property also means that Kong will only do so when the request comes from a trusted client IP. This is also the condition under which the X-Real-IP header will be trusted by Kong or not. In order to enforce security best practices, we took the stance of not trusting any client IP by default. If you wish to rely on such headers, you will need to configure trusted_ips (see the Kong configuration file) to your needs.
  • The API Object property http_if_terminated is now set to false by default. For Kong to evaluate the client X-Forwarded-Proto header, you must now configure Kong to trust the client IP (see above change), and you must explicitly set this value to true. This affects you if you are doing SSL termination somewhere before your requests hit Kong, and if you have configured https_only on the API, or if you use a plugin that requires HTTPS traffic (e.g. OAuth2).
  • The internal DNS resolver now honours the search and ndots configuration options of your resolv.conf file. Make sure that DNS resolution is still consistent in your environment, and consider eventually not using FQDNs anymore.
Admin API
  • Due to the removal of Serf, Kong is now entirely stateless. As such, the /cluster endpoint has for now disappeared. This endpoint, in previous versions of Kong, retrieved the state of the Serf agent running on other nodes to ensure they were part of the same cluster. Starting from 0.11, all Kong nodes connected to the same datastore are guaranteed to be part of the same cluster without requiring additional channels of communication.
  • The Admin API /status endpoint does not return a count of the database entities anymore. Instead, it now returns a database.reachable boolean value, which reflects the state of the connection between Kong and the underlying database. Please note that this flag does not reflect the health of the database itself.
Plugins development
  • The upstream URI is now determined via the Nginx $upstream_uri variable. Custom plugins using the ngx.req.set_uri() API will not be taken into consideration anymore. One must now set the ngx.var.upstream_uri variable from the Lua land.
  • The hooks.lua module for custom plugins is dropped, along with the database_cache.lua module. Database entities caching and eviction has been greatly improved to simplify and automate most caching use-cases. See the plugins development guide for more details about the new underlying mechanism, or see the below section of this document on how to update your plugin's cache invalidation mechanism for 0.11.0.
  • To ensure that the order of execution of plugins is still the same for vanilla Kong installations, we had to update the PRIORITY field of some of our bundled plugins. If your custom plugin must run after or before a specific bundled plugin, you might have to update your plugin's PRIORITY field as well. The complete list of plugins and their priorities is available on the plugins development guide.

Deprecations

CLI
  • The kong compile command has been deprecated. Instead, prefer using the new kong prepare command.

If you use a custom Nginx configuration template from Kong 0.10, before attempting to run any 0.11 node, make sure to apply the following changes to your template:

diff --git a/kong/templates/nginx_kong.lua b/kong/templates/nginx_kong.lua
index 3c038595..faa97ffe 100644
--- a/kong/templates/nginx_kong.lua
+++ b/kong/templates/nginx_kong.lua
@@ -19,25 +19,23 @@ error_log ${{PROXY_ERROR_LOG}} ${{LOG_LEVEL}};
 >-- reset_timedout_connection on; # disabled until benchmarked
 > end

-client_max_body_size 0;
+client_max_body_size ${{CLIENT_MAX_BODY_SIZE}};
 proxy_ssl_server_name on;
 underscores_in_headers on;

-real_ip_header X-Forwarded-For;
-set_real_ip_from 0.0.0.0/0;
-real_ip_recursive on;
-
 lua_package_path '${{LUA_PACKAGE_PATH}};;';
 lua_package_cpath '${{LUA_PACKAGE_CPATH}};;';
 lua_code_cache ${{LUA_CODE_CACHE}};
 lua_socket_pool_size ${{LUA_SOCKET_POOL_SIZE}};
 lua_max_running_timers 4096;
 lua_max_pending_timers 16384;
-lua_shared_dict kong 4m;
-lua_shared_dict cache ${{MEM_CACHE_SIZE}};
-lua_shared_dict cache_locks 100k;
-lua_shared_dict process_events 1m;
-lua_shared_dict cassandra 5m;
+lua_shared_dict kong                5m;
+lua_shared_dict kong_cache          ${{MEM_CACHE_SIZE}};
+lua_shared_dict kong_process_events 5m;
+lua_shared_dict kong_cluster_events 5m;
+> if database == "cassandra" then
+lua_shared_dict kong_cassandra      5m;
+> end
 lua_socket_log_errors off;
 > if lua_ssl_trusted_certificate then
 lua_ssl_trusted_certificate '${{LUA_SSL_TRUSTED_CERTIFICATE}}';
@@ -45,8 +43,6 @@ lua_ssl_verify_depth ${{LUA_SSL_VERIFY_DEPTH}};
 > end

 init_by_lua_block {
-    require 'luarocks.loader'
-    require 'resty.core'
     kong = require 'kong'
     kong.init()
 }
@@ -65,28 +61,19 @@ upstream kong_upstream {
     keepalive ${{UPSTREAM_KEEPALIVE}};
 }

-map $http_upgrade $upstream_connection {
-    default keep-alive;
-    websocket upgrade;
-}
-
-map $http_upgrade $upstream_upgrade {
-    default '';
-    websocket websocket;
-}
-
 server {
     server_name kong;
-    listen ${{PROXY_LISTEN}};
-    error_page 404 408 411 412 413 414 417 /kong_error_handler;
+    listen ${{PROXY_LISTEN}}${{PROXY_PROTOCOL}};
+    error_page 400 404 408 411 412 413 414 417 /kong_error_handler;
     error_page 500 502 503 504 /kong_error_handler;

     access_log ${{PROXY_ACCESS_LOG}};
     error_log ${{PROXY_ERROR_LOG}} ${{LOG_LEVEL}};

+    client_body_buffer_size ${{CLIENT_BODY_BUFFER_SIZE}};

 > if ssl then
-    listen ${{PROXY_LISTEN_SSL}} ssl;
+    listen ${{PROXY_LISTEN_SSL}} ssl${{HTTP2}}${{PROXY_PROTOCOL}};
     ssl_certificate ${{SSL_CERT}};
     ssl_certificate_key ${{SSL_CERT_KEY}};
     ssl_protocols TLSv1.1 TLSv1.2;
@@ -105,9 +92,22 @@ server {
     proxy_ssl_certificate_key ${{CLIENT_SSL_CERT_KEY}};
 > end

+    real_ip_header     ${{REAL_IP_HEADER}};
+    real_ip_recursive  ${{REAL_IP_RECURSIVE}};
+> for i = 1, #trusted_ips do
+    set_real_ip_from   $(trusted_ips[i]);
+> end
+
     location / {
-        set $upstream_host nil;
-        set $upstream_scheme nil;
+        set $upstream_host               '';
+        set $upstream_upgrade            '';
+        set $upstream_connection         '';
+        set $upstream_scheme             '';
+        set $upstream_uri                '';
+        set $upstream_x_forwarded_for    '';
+        set $upstream_x_forwarded_proto  '';
+        set $upstream_x_forwarded_host   '';
+        set $upstream_x_forwarded_port   '';

         rewrite_by_lua_block {
             kong.rewrite()
@@ -118,17 +118,18 @@ server {
         }

         proxy_http_version 1.1;
-        proxy_set_header X-Real-IP $remote_addr;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
-        proxy_set_header Host $upstream_host;
-        proxy_set_header Upgrade $upstream_upgrade;
-        proxy_set_header Connection $upstream_connection;
-        proxy_pass_header Server;
-
-        proxy_ssl_name $upstream_host;
-
-        proxy_pass $upstream_scheme://kong_upstream;
+        proxy_set_header   Host              $upstream_host;
+        proxy_set_header   Upgrade           $upstream_upgrade;
+        proxy_set_header   Connection        $upstream_connection;
+        proxy_set_header   X-Forwarded-For   $upstream_x_forwarded_for;
+        proxy_set_header   X-Forwarded-Proto $upstream_x_forwarded_proto;
+        proxy_set_header   X-Forwarded-Host  $upstream_x_forwarded_host;
+        proxy_set_header   X-Forwarded-Port  $upstream_x_forwarded_port;
+        proxy_set_header   X-Real-IP         $remote_addr;
+        proxy_pass_header  Server;
+        proxy_pass_header  Date;
+        proxy_ssl_name     $upstream_host;
+        proxy_pass         $upstream_scheme://kong_upstream$upstream_uri;

         header_filter_by_lua_block {
             kong.header_filter()
@@ -146,7 +147,7 @@ server {
     location = /kong_error_handler {
         internal;
         content_by_lua_block {
-            require('kong.core.error_handlers')(ngx)
+            kong.handle_error()
         }
     }
 }
@@ -162,7 +163,7 @@ server {
     client_body_buffer_size 10m;

 > if admin_ssl then
-    listen ${{ADMIN_LISTEN_SSL}} ssl;
+    listen ${{ADMIN_LISTEN_SSL}} ssl${{ADMIN_HTTP2}};
     ssl_certificate ${{ADMIN_SSL_CERT}};
     ssl_certificate_key ${{ADMIN_SSL_CERT_KEY}};
     ssl_protocols TLSv1.1 TLSv1.2;
@@ -176,15 +177,7 @@ server {
     location / {
         default_type application/json;
         content_by_lua_block {
-            ngx.header['Access-Control-Allow-Origin'] = '*'
-
-            if ngx.req.get_method() == 'OPTIONS' then
-                ngx.header['Access-Control-Allow-Methods'] = 'GET,HEAD,PUT,PATCH,POST,DELETE'
-                ngx.header['Access-Control-Allow-Headers'] = 'Content-Type'
-                ngx.exit(204)
-            end
-
-            require('lapis').serve('kong.api')
+            kong.serve_admin_api()
         }
     }

Once those changes have been applied, you will be able to benefit from the new configuration properties and bug fixes that 0.11 introduces.

If you are maintaining your own plugin, and if you are using the 0.10.x database_cache.lua module to cache your datastore entities, you probably included a hooks.lua module in your plugin as well.

In 0.11, most of the clutter surrounding cache invalidation is now gone, and handled automatically by Kong for most use-cases.

  • The hooks.lua module is now ignored by Kong. You can safely remove it from your plugins.
  • The database_cache.lua module is replaced with singletons.cache. You should not require database_cache anymore in your plugin's code.

To update your plugin's caching mechanism to 0.11, you must implement automatic or manual invalidation.

Automatic cache invalidation

Let's assume your plugin had the following code that we wish to update for 0.11 compatibility:

local credential, err = cache.get_or_set(cache.keyauth_credential_key(key),
                                         nil, load_credential, key)
if err then
  return responses.send_HTTP_INTERNAL_SERVER_ERROR(err)
end

Along with the following hooks.lua file:

local events = require "kong.core.events"
local cache = require "kong.tools.database_cache"

local function invalidate(message_t)
  if message_t.collection == "keyauth_credentials" then
    cache.delete(cache.keyauth_credential_key(message_t.old_entity     and
                                              message_t.old_entity.key or
                                              message_t.entity.key))
  end
end

return {
  [events.TYPES.ENTITY_UPDATED] = function(message_t)
    invalidate(message_t)
  end,
  [events.TYPES.ENTITY_DELETED] = function(message_t)
    invalidate(message_t)
  end
}

By adding the following cache_key property to your custom entity's schema:

local SCHEMA = {
  primary_key = { "id" },
  table = "keyauth_credentials",
  cache_key = { "key" }, -- cache key for this entity
  fields = {
    id = { type = "id" },
    consumer_id = { type = "id", required = true, foreign = "consumers:id"},
    key = { type = "string", required = false, unique = true }
  }
}

return { keyauth_credentials = SCHEMA }

You can now generate a unique cache key for that entity and cache it like so in your business logic and hot code paths:

local singletons = require "kong.singletons"

local apikey = request.get_uri_args().apikey
local cache_key = singletons.dao.keyauth_credentials:cache_key(apikey)

local credential, err = singletons.cache:get(cache_key, nil, load_entity_key,
                                             apikey)
if err then
  return response.HTTP_INTERNAL_SERVER_ERROR(err)
end

-- do something with the retrieved credential

Now, cache invalidation will be an automatic process: every CRUD operation that affects this API key will be make Kong auto-generate the affected cache_key, and send broadcast it to all of the other nodes on the cluster so they can evict that particular value from their cache, and fetch the fresh value from the datastore on the next request.

When a parent entity is receiving a CRUD operation (e.g. the Consumer owning this API key, as per our schema's consumer_id attribute), Kong performs the cache invalidation mechanism for both the parent and the child entity.

Thanks to this new property, the hooks.lua module is not required anymore and your plugins can perform datastore caching much more easily.

Manual cache invalidation

In some cases, the cache_key property of an entity's schema is not flexible enough, and one must manually invalidate its cache. Reasons for this could be that the plugin is not defining a relationship with another entity via the traditional foreign = "parent_entity:parent_attribute" syntax, or because it is not using the cache_key method from its DAO, or even because it is somehow abusing the caching mechanism.

In those cases, you can manually setup your own subscriber to the same invalidation channels Kong is listening to, and perform your own, custom invalidation work. This process is similar to the old hooks.lua module.

To listen on invalidation channels inside of Kong, implement the following in your plugin's init_worker handler:

local singletons = require "kong.singletons"

function MyCustomHandler:init_worker()
  local worker_events = singletons.worker_events

  -- listen to all CRUD operations made on Consumers
  worker_events.register(function(data)

  end, "crud", "consumers")

  -- or, listen to a specific CRUD operation only
  worker_events.register(function(data)
    print(data.operation)  -- "update"
    print(data.old_entity) -- old entity table (only for "update")
    print(data.entity)     -- new entity table
    print(data.schema)     -- entity's schema
  end, "crud", "consumers:update")
end

Once the above listeners are in place for the desired entities, you can perform manual invalidations of any entity that your plugin has cached as you wish so. For instance:

singletons.worker_events.register(function(data)
  if data.operation == "delete" then
    local cache_key = data.entity.id
    singletons.cache:invalidate("prefix:" .. cache_key)
  end
end, "crud", "consumers")

You can now start migrating your cluster from 0.10.x to 0.11. If you are doing this upgrade "in-place", against the datastore of a running 0.10 cluster, then for a short period of time, your database schema won't be fully compatible with your 0.10 nodes anymore. This is why we suggest either performing this upgrade when your 0.10 cluster is warm and most entities are cached, or against a new database, if you can migrate your data. If you wish to temporarily make your APIs unavailable, you can leverage the new request-termination plugin.

The path to upgrade a 0.10 datastore is identical to the one of previous major releases:

  1. If you are planning on upgrading Kong while 0.10 nodes are running against the same datastore, make sure those nodes are warm enough (they should have most of your entities cached already), or temporarily disable your APIs.
  2. Provision a 0.11 node and configure it as you wish (environment variables/ configuration file). Make sure to point this new 0.11 node to your current datastore.
  3. Without starting the 0.11 node, run the 0.11 migrations against your current datastore:
$ kong migrations up [-c kong.conf]

As usual, this step should be executed from a single node.

  1. You can now provision a fresh 0.11 cluster pointing to your migrated datastore and start your 0.11 nodes.
  2. Gradually switch your traffic from the 0.10 cluster to the new 0.11 cluster. Remember, once your database is migrated, your 0.10 nodes will rely on their cache and not on the underlying database. Your traffic should switch to the new cluster as quickly as possible.
  3. Once your traffic is fully migrated to the 0.11 cluster, decommission your 0.10 cluster.

Once all of your 0.10 nodes are fully decommissioned, you can consider removing the Serf executable from your environment as well, since Kong 0.11 does not depend on it anymore.

Upgrade to 0.10.x

Due to the breaking changes introduced in this version, we recommend that you carefully test your cluster deployment.

Kong 0.10 introduced the following breaking changes:

  • API Objects (as configured via the Admin API) do not support the request_host and request_uri fields anymore. The 0.10 migrations should upgrade your current API Objects, but make sure to read the new 0.10 Proxy Guide to learn the new routing capabilities of Kong. This means that Kong can now route incoming requests according to a combination of Host headers, URIs, and HTTP methods.
  • The upstream_url field of API Objects does not accept trailing slashes anymore.
  • Dynamic SSL certificates serving is now handled by the core, and not through the ssl plugin anymore. This version introduced the /certificates and /snis endpoints. See the new 0.10 Proxy Guide to learn more about how to configure your SSL certificates on your APIs. The ssl plugin has been removed.
  • The preferred version of OpenResty is now 1.11.2.2. However, this version requires that you compiled OpenResty with the --without-luajit-lua52 flag. Make sure to do so if you install OpenResty and Kong from source.
  • Dnsmasq is not a dependency anymore (However, be careful before removing it if you configured it to be your DNS name server via Kong's resolver property)
  • The cassandra_contact_points property does not allow specifying a port anymore. All Cassandra nodes must listen on the same port, which can be tweaked via the cassandra_port property.
  • If you are upgrading to 0.10.1 or 0.10.2 and using the CORS plugin, pay extra attention to a regression that was introduced in 0.10.1: Previously, the plugin would send the * wildcard when config.origin was not specified. With this change, the plugin does not send the * wildcard by default anymore. You will need to specify it manually when configuring the plugin, with config.origins=*. This behavior is to be fixed in a future release.

We recommend that you consult the full 0.10.0 Changelog for a full list of changes and new features, including load balancing capabilities, support for Cassandra 3.x, SRV records resolution, and much more.

Here is how to ensure a smooth upgrade from a Kong 0.9.x cluster to 0.10:

  1. Make sure your 0.9 cluster is warm because your datastore will be incompatible with your 0.9 Kong nodes once migrated. Most of your entities should be cached by the running Kong nodes already (APIs, Consumers, Plugins).
  2. Provision a 0.10 node and configure it as you wish (environment variables/ configuration file). Make sure to point this new 0.10 node to your current datastore.
  3. Without starting the 0.10 node, run the 0.10 migrations against your current datastore:
$ kong migrations up <-c kong.conf>

As usual, this step should be executed from a single node.

  1. You can now provision a fresh 0.10 cluster pointing to your migrated datastore and start your 0.10 nodes.
  2. Gradually switch your traffic from the 0.9 cluster to the new 0.10 cluster. Remember, once your database is migrated, your 0.9 nodes will rely on their cache and not on the underlying database. Your traffic should switch to the new cluster as quickly as possible.
  3. Once your traffic is fully migrated to the 0.10 cluster, decommission your 0.9 cluster.

Upgrade to 0.9.x

PostgreSQL is the new default datastore for Kong. If you were using Cassandra and you are upgrading, you must explicitly set cassandra as your database.

This release introduces a new CLI, which uses the lua-resty-cli interpreter. As such, the resty executable (shipped in the OpenResty bundle) must be available in your $PATH. Additionally, the bin/kong executable is not installed through Luarocks anymore, and must be placed in your $PATH as well. This change of behavior is taken care of if you are using one of the official Kong packages.

Once Kong updated, familiarize yourself with its new configuration format, and consider setting some of its properties via environment variables, if the need arises. This behavior as well as all available settings are documented in the kong.conf.default file shipped with this version.

Once your nodes configured, we recommend that you seamingly redirect your traffic through the new Kong 0.9 nodes before decomissioning your old nodes.

Upgrade to 0.8.x

No important breaking changes for this release, just be careful to not use the long deprecated routes /consumers/:consumer/keyauth/ and /consumers/:consumer/basicauth/ as instructed in the Changelog. As always, also make sure to check the configuration file for new properties (this release allows you to configure the read/write consistency of Cassandra).

Let's talk about PostgreSQL. To use it instead of Cassandra, follow those steps:

  • Get your hands on a 9.4+ server (being compatible with Postgres 9.4 allows you to use Amazon RDS)
  • Create a database, (maybe a user too?), let's say kong
  • Update your Kong configuration:
# as always, be careful about your YAML formatting
database: postgres
postgres:
  host: "127.0.0.1"
  port: 5432
  user: kong
  password: kong
  database: kong

As usual, migrations should run from kong start, but as a reminder and just in case, here are some tips:

Reset the database with (careful, you'll lose all data):

$ kong migrations reset --config kong.yml

Run the migrations manually with:

$ kong migrations up --config kong.yml

If needed, list your migrations for debug purposes with:

$ kong migrations list --config kong.yml

Note: This release does not provide a mean to migrate from Cassandra to PostgreSQL. Additionally, we recommend that you do not use kong reload if you switch your cluster from Cassandra to PostgreSQL. Instead, we recommend that you migrate by spawning a new cluster and gradually redirect your traffic before decomissioning your old nodes.

Upgrade to 0.7.x

If you are running a source installation, you will need to upgrade OpenResty to its 1.9.7.* version. The good news is that this family of releases does not need to patch the NGINX core anymore to enable SSL support. If you install Kong from one of the distribution packages, they already include the appropriate OpenResty, simply download and install the appropriate package for your platform.

As described in the Changelog, this upgrade has benefits, such as the SSL support and fixes for critical NGINX vulnerabilities, but also requires that you upgrade the nginx property of your Kong config, because it is not backwards compatible.

  • We advise that you retrieve the nginx property from the 0.7.x configuration file, and use it in yours with the changes you feel are appropriate.

  • Finally, you can reload Kong as usual:

$ kong reload [-c configuration_file]

Note: We expose the underlying NGINX configuration as a way for Kong to be as flexible as possible and allow you to bend your NGINX instance to your needs. We are aware that many of you do not need to customize it and such changes should not affect you. Plans are to embed the NGINX configuration in Kong, while still allowing customization for the most demanding users. #217 is the place to discuss this and share thoughts/needs.

Upgrade to 0.6.x

Note: if you are using Kong 0.4.x or earlier, you must first upgrade to Kong 0.5.x.

The configuration file changed in this release. Make sure to check out the new default one and update it to your needs. In particular, make sure that:

plugins_available:
  - key-auth
  - ...
  - custom-plugin
proxy_port: ...
proxy_ssl_port: ...
admin_api_port: ...
databases_available:
  cassandra:
    properties:
      contact_points:
        - ...

becomes:

custom_plugins:
  - only-custom-plugins
proxy_listen: ...
proxy_listen_ssl: ...
admin_api_listen: ...
cassandra:
  contact_points:
    - ...

Secondly, if you installed Kong from source or maintain a development installation, you will need to have Serf installed on your system and available in your $PATH. Serf is included with all the distribution packages and images available at getkong.org/install.

The same way, this should already be the case but make sure that LuaJIT is in your $PATH too as the CLI interpreter switched from Lua 5.1 to LuaJIT. Distribution packages also include LuaJIT.

In order to start Kong with its new clustering and cache invalidation capabilities, you will need to restart your node(s) (and not reload):

$ kong restart [-c configuration_file]

Read more about the new clustering capabilities of Kong 0.6.0 and its configurations in the Clustering documentation.

Upgrade to 0.5.x

Migrating to 0.5.x can be done without downtime by following those instructions. It is important that you be running Kong 0.4.2 and have the latest release of Python 2.7 on your system when executing those steps.

Several changes were introduced in this version: some plugins and properties were renamed and the database schema slightly changed to introduce "plugins migrations". Now, each plugin can have its own migration if it needs to store data in your cluster. This is not a regular migration since the schema of the table handling the migrations itself changed.

1. Configuration file

You will need to update your configuration file. Replace the plugins_available values with:

plugins_available:
  - ssl
  - jwt
  - acl
  - cors
  - oauth2
  - tcp-log
  - udp-log
  - file-log
  - http-log
  - key-auth
  - hmac-auth
  - basic-auth
  - ip-restriction
  - mashape-analytics
  - request-transformer
  - response-transformer
  - request-size-limiting
  - rate-limiting
  - response-ratelimiting

You can still remove plugins you don't use for a lighter Kong.

Also replace the Cassandra hosts property with contact_points:

properties:
  contact_points:
    - "..."
    - "..."
  timeout: 1000
  keyspace: kong
  keepalive: 60000
2. Migration script

This Python script will take care of migrating your database schema should you execute the following instructions:

# First, make sure you are already running Kong 0.4.2

# Clone the Kong git repository if you don't already have it:
$ git clone https://github.com/Kong/kong.git

# Go to the 'scripts/' folder:
$ cd kong/scripts

# Install the Python script dependencies:
$ pip install cassandra-driver==2.7.2 pyyaml

# The script will use the first Cassandra contact point in your Kong configuration file
# (the first of the 'contact_points' property) so make sure it is valid and has the format 'host:port'.

# Run the migration script:
$ python migration.py -c /path/to/kong/config

If everything went well the script should print a success message. At this point, your database is compatible with both Kong 0.4.2 and 0.5.x. If you are running more than one Kong node, you simply have to follow step 3. for each one of them now.

3. Upgrade without downtime

You can now upgrade Kong to 0.5.x. Proceed as a regular upgrade and follow the suggested upgrade path, in particular the kong reload command.

4. Purge your Cassandra cluster

Finally, once Kong has restarted in 0.5.x, run the migration script again, with the --purge flag:

$ python migration.py -c /path/to/kong/config --purge

Your cluster is now fully migrated to 0.5.x.

Other changes to acknowledge

Some entities and properties were renamed to avoid confusion:

  • Properties belonging to APIs entities have been renamed for clarity:
    • public_dns -> request_host
    • path -> request_path
    • strip_path -> strip_request_path
    • target_url -> upstream_url
  • plugins_configurations have been renamed to plugins, and their value property has been renamed to config to avoid confusions.
  • The Key authentication and Basic authentication plugins routes have changed:
Old route                             New route
/consumers/:consumer/keyauth       -> /consumers/:consumer/key-auth
/consumers/:consumer/keyauth/:id   -> /consumers/:consumer/key-auth/:id
/consumers/:consumer/basicauth     -> /consumers/:consumer/basic-auth
/consumers/:consumer/basicauth/:id -> /consumers/:consumer/basic-auth/:id

The old routes are still maintained but will be removed in upcoming versions. Consider them deprecated.

  • Admin API:
    • The route to retrieve enabled plugins is now under /plugins/enabled.
    • The route to retrieve a plugin's configuration schema is now under /plugins/schema/{plugin name}.

Upgrade to Kong 0.4.2

The configuration format for specifying the port of your Cassandra instance changed. Replace:

cassandra:
  properties:
    hosts: "localhost"
    port: 9042

by:

cassandra:
  properties:
    hosts:
      - "localhost:9042"

Upgrade to 0.3.x

Kong now requires a patch on OpenResty for SSL support. On Homebrew you will need to reinstall OpenResty.

Homebrew

$ brew update
$ brew reinstall mashape/kong/ngx_openresty
$ brew upgrade kong

Troubleshoot

If you are seeing a similar error on kong start:

nginx: [error] [lua] init_by_lua:5: Startup error: Cassandra error: Failed to
prepare statement: "SELECT id FROM apis WHERE path = ?;". Cassandra returned
error (Invalid): "Undefined name path in where clause ('path = ?')"

You can run the following command to update your schema:

$ kong migrations up

Please consider updating to 0.3.1 or greater which automatically handles the schema migration.