Download photoshop plugins for free. Photo & Graphics tools downloads - Shutterstock Photoshop Plugin Installer by Shutterstock, Inc. And many more programs are available for instant and free download. Mix ecto.migrate. Now we can use the DynamicCron plugin and start scheduling periodic jobs! Using and Configuring To begin using DynamicCron, add the module to your list of Oban plugins in config.exs: config:myapp, Oban, plugins: Oban.Pro.Plugins.DynamicCron.
🌟 This plugin is available through Oban.Pro
The DynamicCron
plugin enhances Oban's built in cron scheduler by making itconfigurable at runtime, globally, across your entire cluster. DynamicCron
supports adding, updating, deleting, and pausing cron entries at boot time orruntime. It is an ideal solution for applications that must dynamically startand manage scheduled tasks at runtime.
Before running the DynamicCron
plugin you must run a migration to add theoban_cron
table to your database.
Open the generated migration in your editor and call the change
function onOban.Pro.Migrations.DynamicCron
:
As with the base Oban tables you can optionally provide a prefix
to'namespace' the table within your database. Here we specify a 'private'
prefix:
Run the migration to create the table:
Now we can use the DynamicCron
plugin and start scheduling periodic jobs!
To begin using DynamicCron
, add the module to your list of Oban plugins inconfig.exs
:
By itself, without providing a crontab or dynamically inserting cron entries,the plugin doesn't have anything to schedule. To get scheduling started, providea list of {cron, worker}
or {cron, worker, options}
tuples to the plugin.The syntax is identical to Oban's built in :crontab
option, which means youcan copying an existing standard :crontab
list into the plugin's :crontab
.
For more details about periodic jobs and cron expressions see the documentationon Periodic Jobs.
Now, when the dynamic pruner initializes, it will persist those cron entries tothe database and start scheduling them according to their CRON expression. Theplugin's crontab
format is nearly identical to Oban's standard crontab, with afew important enhancements we'll look at soon.
Each of the crontab entries are persisted to the database and referencedglobally, by all the other connected Oban instances. That allows us to insert,update, or delete cron entries at any time. In fact, changing the schedule oroptions of an entry in the crontab provided to the plugin will automaticallyupdate the persisted entry. To demonstrate, let's modify the MinuteJob
wespecified so that it runs every other minute in the :scheduled
queue:
Now it isn't really a 'minute job' any more, and the name is no longer suitable.However, we didn't provide a name for the entry and it's using the module nameinstead. To provide more flexibility we can add a :name
overrride, then we canupdate the worker's name as well:
All entries are referenced by name, which defaults to the worker's name and mustbe unique. You may define the same worker multiple times as long as youprovide a name override:
To temporarily disable scheduling jobs you can set the paused
flag:
To resume the job you must supply paused: false
(or use update/2
to resumeit manually), simply removing the paused
option will have no effect.
It is also possible to delete a persisted entry during initialization by passingthe :delete
option:
One or more entries can be deleted this way. Deleting entries is idempotent,nothing will happen if no matching entry can be found.
In the next section we'll look at how to list, insert, update and delete jobsdynamically at runtime.
Dynamic cron entries are persisted to the database, making it easy to manipulatethem through typical CRUD operations. The DynamicCron
plugin providesconvenience functions to simplify working those operations. In this sectionwe'll walk through each of the available functions and look at some examples.
📚 In order to bridge the gap between module level docs and a guide, each sectionincludes a typespec for the corresponding function. The snippet below defines thetypes listed in each section.
The insert/1
function takes a list of one or more tuples with the same{expression, worker}
or {expression, worker, options}
format as the plugin'scrontab
option:
Be aware that insert/1
acts like an 'upsert', making it possible to modifyexisting entries if the worker or name matches. Still, it is better to useupdate/2
to make targeted updates.
The update/2
function updates a single cron entry, as identified by the workeror name. Any option available when specifying an entry in the crontab
list orwhen calling insert/2
can be updated—that includes the cron expression
andthe worker
.
The following call demonstrates updating every possible option:
Naturally, individual options may be updated instead. For example, set paused: true
to pause an entry:
Since update/2
operates on a single entry at a time, it is possible to renamean entry without doing a delete
/insert
dance:
The delete/1
function operates on individual entries, by worker or name. Youcan use it to delete entries at runtime, rather than hard-coding the :delete
flag into the crontab
list at compile time.
Use all/0
to retrieve all persisted cron entries:
This returns a list of Oban.Pro.Cron
schemas with raw attributes. The all/0
function is provided as a convenience to inspect persisted entries.
As Oban.Pro.Cron
is an Ecto schema you're free to query the table however youwish using Ecto.Query
. For example, you can list all of the entries with aname like 'client-':
You can use functions like update
or update_all
to modify cron jobs inplace, but it is highly recommended that you use update/2
to ensure thatoptions are set correctly and to prevent breakage.
Without any configuration the default timezone is Etc/UTC
. You can overridethat for all cron entries by passing a timezone
option to the plugin:
You can also override the timezone for individual entries by passing it as anoption to the crontab
list or to DynamicCron.insert/1
:
All DynamicCron
functions have an alternate clause that accepts an Obaninstance name as the first argument. This is in line with base Oban
functionssuch as Oban.insert/2
, which allow you to seamlessly work with multipleOban instances and across multiple database prefixes. For example, you can uselist/1
to list all cron entries for the instance named ObanPrivate
:
Likewise, to insert a new entry using the configuration associated with theObanPrivate
instance:
The DynamicCron
plugin adds the following metadata to the [:oban, :plugin, :stop]
event:
:jobs
- a list of jobs that were inserted into the databaseSee the docs on Plugin Events fordetails.
How to use Timex DateTimes with Ecto.
Timex has can be integrated with Ecto via the timex_ecto
plugin which is available on hex.pm:
Timex-Ecto exposes a few different types for you to use:
Timex.Ecto.Date
: An ISO date (YYYY-MM-DD
)Timex.Ecto.Time
: An ISO time (hh:mm:ss.sss
)Timex.Ecto.DateTime
: An ISO 8601 datetime in UTCTimex.Ecto.DateTimeWithTimezone
: Same as DateTime, but contains the timezone, i.e. America/Chicago
as well. NOTE currently this is only supported with PostgreSQL, as it relies on complex types which are not currently supported in MySQL, and SQL Server user defined types require CLR types backing them which I have not explored in depth as of yet. See the section below titled Using DateTimeWithTimezone for details.In order to use the Timex DateTime type instead of the Ecto DateTime type, your model should look something like the following:
timestamps
macroSuper simple! Your timestamps will now be DateTime
structs instead of Ecto.DateTime
structs.
Phoenix allows you to apply defaults globally to Ecto models via web/web.ex
by changing the model
function like so:
By doing this, you bring the Timex timestamps into scope in all your models.
NOTE: This currently only applies to PostgreSQL.
You must run the following SQL against the database you plan on using this type with:
You can then use this type like so:
That's it!
The following is a simple test app I built for vetting this plugin:
And the results:
And that's all there is to it!