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    <title>epazote</title>
    <link>https://epazote.io/index.xml</link>
    <description>Recent content on epazote</description>
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    <language>en-us</language>
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    <lastBuildDate>Tue, 20 Sep 2016 21:26:25 +0200</lastBuildDate>
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    <item>
      <title>🌿  epazote</title>
      <link>https://epazote.io/about/</link>
      <pubDate>Tue, 20 Sep 2016 21:26:25 +0200</pubDate>
      
      <guid>https://epazote.io/about/</guid>
      <description>

&lt;h1 id=&#34;what-is-epazote&#34;&gt;What is epazote?&lt;/h1&gt;

&lt;p&gt;An automated HTTP (microservices) supervisor.&lt;/p&gt;

&lt;p&gt;&lt;a href=&#34;https://asciinema.org/a/86545&#34;&gt;&lt;img src=&#34;https://asciinema.org/a/86545.png&#34; alt=&#34;asciicast&#34; /&gt;&lt;/a&gt;&lt;/p&gt;

&lt;h2 id=&#34;why&#34;&gt;Why ?&lt;/h2&gt;

&lt;p&gt;Because of the need to monitor with simplicity for example:&lt;/p&gt;

&lt;ul&gt;
&lt;li&gt;A simple check (Status 200 OK) every 30 seconds.&lt;/li&gt;
&lt;li&gt;Receive an email/http alert if the SSL certifciate is about to expire.&lt;/li&gt;
&lt;li&gt;Check if the application is serving the proper headers.&lt;/li&gt;
&lt;li&gt;Restart DB/App/etc based on headers or staus codes.&lt;/li&gt;
&lt;/ul&gt;

&lt;hr /&gt;

&lt;p&gt;Once your site/application is up and running, it can become idle and
unresponsive, your &lt;a href=&#34;https://immortal.run&#34;&gt;supervisor&lt;/a&gt; will not notice
this, since in most of the cases is just responsible for keeping your
application process up and running no matter how it is behaving, therefore
exists the need to monitor the status of the application and based on the
responses take actions, here is where &lt;strong&gt;Epazote&lt;/strong&gt; comes into action.&lt;/p&gt;

&lt;p&gt;When doing Continuous Deployment
&amp;ldquo;&lt;a href=&#34;https://en.wikipedia.org/wiki/Continuous_delivery&#34;&gt;CD&lt;/a&gt;&amp;rdquo; if the ping,
healthcheck, status, etc; endpoints change, it implies making changes in order
to properly monitor the application, this creates a dependency or extra task
apart from the &amp;ldquo;CD&amp;rdquo; process, therefore exists the need to detect any changes and
automatically apply them upon request, this can be done easily with &lt;strong&gt;Epazote&lt;/strong&gt;.&lt;/p&gt;
</description>
    </item>
    
    <item>
      <title>How it works</title>
      <link>https://epazote.io/post/how-it-works/</link>
      <pubDate>Tue, 20 Sep 2016 04:00:00 +0000</pubDate>
      
      <guid>https://epazote.io/post/how-it-works/</guid>
      <description>&lt;p&gt;In its basic way of operation,  &lt;strong&gt;Epazote&lt;/strong&gt; periodically checks the services endpoints
&amp;ldquo;&lt;a href=&#34;https://en.wikipedia.org/wiki/Uniform_Resource_Locator&#34;&gt;URLs&lt;/a&gt;&amp;ldquo;
by doing an &lt;a href=&#34;https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Request_methods&#34;&gt;HTTP GET Request&lt;/a&gt;,
based on the response &lt;a href=&#34;https://en.wikipedia.org/wiki/List_of_HTTP_status_codes&#34;&gt;Status code&lt;/a&gt;,
&lt;a href=&#34;https://en.wikipedia.org/wiki/List_of_HTTP_header_fields&#34;&gt;Headers&lt;/a&gt; or
either the
&lt;a href=&#34;https://en.wikipedia.org/wiki/HTTP_message_body&#34;&gt;body&lt;/a&gt;, it executes a command.&lt;/p&gt;

&lt;p&gt;In most scenarios, is desired to apply a command directly to the application in
cause, like a signal (&lt;code&gt;kill -HUP&lt;/code&gt;), or either a restart, therefore in this
case &lt;strong&gt;Epazote&lt;/strong&gt; and the application should be running on the same server.&lt;/p&gt;

&lt;p&gt;&lt;strong&gt;Epazote&lt;/strong&gt; can also work in a standalone mode by only monitoring and sending
alerts if desired.&lt;/p&gt;

&lt;p&gt;&lt;a href=&#34;https://asciinema.org/a/86545&#34;&gt;&lt;img src=&#34;https://asciinema.org/a/86545.png&#34; alt=&#34;asciicast&#34; /&gt;&lt;/a&gt;&lt;/p&gt;
</description>
    </item>
    
    <item>
      <title>How to use it</title>
      <link>https://epazote.io/post/how-to-use-it/</link>
      <pubDate>Tue, 20 Sep 2016 02:00:00 +0000</pubDate>
      
      <guid>https://epazote.io/post/how-to-use-it/</guid>
      <description>

&lt;h1 id=&#34;how-to-use-it&#34;&gt;How to use it&lt;/h1&gt;

&lt;p&gt;First you need to install &lt;strong&gt;Epazote&lt;/strong&gt;, either you can compile it from
&lt;a href=&#34;https://github.com/epazote/epazote&#34;&gt;source&lt;/a&gt;
or download a pre-compiled binary matching your operating system from here:
&lt;a href=&#34;https://bintray.com/nbari/epazote/epazote/_latestVersion&#34;&gt;https://bintray.com/nbari/epazote/epazote/_latestVersion&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;To compile from source, after downloading the sources use &lt;code&gt;make&lt;/code&gt; to build the
binary:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;~/projects/go/src/github.com/epazote/epazote
$ make
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;&lt;strong&gt;Epazote&lt;/strong&gt; was designed with simplicity in mind, as an easy tool for
 &lt;a href=&#34;https://en.wikipedia.org/wiki/DevOps&#34;&gt;DevOps&lt;/a&gt; and as a complement to
 infrastructure orchestration tools like &lt;a href=&#34;http://www.ansible.com/&#34;&gt;Ansible&lt;/a&gt; and
 &lt;a href=&#34;http://saltstack.com/&#34;&gt;SaltStack&lt;/a&gt;, because of this &lt;a href=&#34;http://www.yaml.org/&#34;&gt;YAML&lt;/a&gt;
 is used for the configuration files, avoiding with this, the learn of a new
 language or syntax and simplifying the setup.&lt;/p&gt;

&lt;h2 id=&#34;basic-example&#34;&gt;Basic example&lt;/h2&gt;

&lt;pre&gt;&lt;code&gt;services:
    google:
        url: https://www.google.com
        seconds: 5
        expect:
            status: 302
            ssl:
                hours: 72
            if_not:
                cmd: echo -n &amp;quot;google down&amp;quot;
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;To supervise &lt;code&gt;google&lt;/code&gt; you would run (basic.yml is a file containing the above code):&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;$ epazote -f /path/to/yaml/file/basic.yml -d
&lt;/code&gt;&lt;/pre&gt;

&lt;blockquote&gt;
&lt;p&gt;-d is for debugging, will print all output to standard output.&lt;/p&gt;
&lt;/blockquote&gt;

&lt;p&gt;&lt;a href=&#34;https://asciinema.org/a/86545&#34;&gt;&lt;img src=&#34;https://asciinema.org/a/86545.png&#34; alt=&#34;asciicast&#34; /&gt;&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;This example, will supervise every 5 seconds the service with name
&lt;code&gt;google&lt;/code&gt;, it will do an HTTP GET to &lt;code&gt;http://www.google.com&lt;/code&gt; and will expect
an &lt;code&gt;302 Status code&lt;/code&gt; if not,  it will &lt;code&gt;echo -n &amp;quot;google down&amp;quot;&lt;/code&gt;&lt;/p&gt;

&lt;p&gt;The &lt;code&gt;ssl: hours: 72&lt;/code&gt; means to send an alert if the certificate is about to
expire in the next 72 hours.&lt;/p&gt;

&lt;p&gt;Extending the basic example for receiving notifications:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;config:
    smtp:
        username: smtp@domain.tld
        password: password
        server: mail.example.com
        port: 587
        headers:
            from: you@domain.tld
            to: team@domain.tld
            subject: &amp;quot;[_name_, _because_]&amp;quot;

services:
    google:
        url: http://www.google.com
        minutes: 3
        threshold:
            healthy: 2 # consecutive successes
            unhealthy: 2 # consecutive failures
        expect:
            status: 200
            if_not:
                cmd: echo -n &amp;quot;google down&amp;quot;
                notify: yes
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;In this case, every 3 minutes the service will be checked and in case of not
receiving a &lt;code&gt;200 Status code&lt;/code&gt; more than 2 times:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;threshold:
    unhealthy: 2
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;Besides executing the command: &lt;code&gt;echo -n &amp;quot;google down&amp;quot;&lt;/code&gt; an email is going to be
send to &lt;code&gt;team@domain.tld&lt;/code&gt;, this because of the &lt;code&gt;notify: yes&lt;/code&gt; setting.&lt;/p&gt;

&lt;p&gt;After getting 2 consecutive successful responses &lt;code&gt;200 status code&lt;/code&gt;, an alert
is also sent.&lt;/p&gt;

&lt;h2 id=&#34;the-configuration-file&#34;&gt;The configuration file&lt;/h2&gt;

&lt;p&gt;The configuration file (&lt;a href=&#34;https://en.wikipedia.org/wiki/YAML&#34;&gt;YAML formated&lt;/a&gt;)
consists of two parts, a &lt;a href=&#34;https://epazote.io/post/the-config/&#34;&gt;config&lt;/a&gt; and a &lt;a href=&#34;https://epazote.io/post/the-services&#34;&gt;services&lt;/a&gt; (Key-value pairs).&lt;/p&gt;
</description>
    </item>
    
    <item>
      <title>The config</title>
      <link>https://epazote.io/post/the-config/</link>
      <pubDate>Tue, 20 Sep 2016 02:00:00 +0000</pubDate>
      
      <guid>https://epazote.io/post/the-config/</guid>
      <description>

&lt;h1 id=&#34;the-config-section&#34;&gt;The config section&lt;/h1&gt;

&lt;p&gt;The &lt;strong&gt;config&lt;/strong&gt; section is composed of:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;- smtp (Email settings for sending notification)
- scan (Paths used to find the file &#39;epazote.yml&#39;)
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;Example:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;config:
    smtp:
        username: smtp@domain.tld
        password: password
        server: mail.example.com
        port: 587
        headers:
            from: epazote@domain.tld
            to: team@domain.tld ops@domain.tld etc@domain.tld
            subject: &amp;quot;[_name_, _because_]&amp;quot;
    scan:
        paths:
            - /arena/home/sites
            - /home/apps
        minutes: 5
&lt;/code&gt;&lt;/pre&gt;

&lt;h3 id=&#34;config-smtp&#34;&gt;config - smtp&lt;/h3&gt;

&lt;p&gt;Required to properly send alerts via email, all fields are required, the
&lt;code&gt;headers&lt;/code&gt; section can be extended with any desired key-pair values.&lt;/p&gt;

&lt;h3 id=&#34;config-smtp-subject&#34;&gt;config - smtp - subject&lt;/h3&gt;

&lt;p&gt;The subject can be formed by using this keywords:&lt;/p&gt;

&lt;pre&gt;&lt;code class=&#34;language-sh&#34;&gt;    _because_  _exit_ _name_ _output_ _status_ _url_
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;on the previous example, &lt;code&gt;subject: [_name_, _status_]&lt;/code&gt; would transform to
&lt;code&gt;[my service - 500]&lt;/code&gt; the &lt;code&gt;name&lt;/code&gt; has replaced by the service name, &lt;code&gt;my
service&lt;/code&gt; and &lt;code&gt;status&lt;/code&gt; by the response status code &lt;code&gt;500&lt;/code&gt; in this case.&lt;/p&gt;

&lt;h3 id=&#34;config-scan&#34;&gt;config - scan&lt;/h3&gt;

&lt;p&gt;Paths to scan every N &lt;code&gt;seconds&lt;/code&gt;, &lt;code&gt;minutes&lt;/code&gt; or &lt;code&gt;hours&lt;/code&gt;, a search for
services specified in a file call &lt;code&gt;epazote.yml&lt;/code&gt; is made.&lt;/p&gt;

&lt;p&gt;The &lt;strong&gt;scan&lt;/strong&gt; setting is optional however is very useful when doing Continues
Deployments. for example if your code is automatically uploaded to the
directory &lt;code&gt;/arena/home/sites/application_1&lt;/code&gt; and your scan paths contain
&lt;code&gt;/arena/home/sites&lt;/code&gt;, you could simple upload on your application directory a
file named &lt;code&gt;epazote.yml&lt;/code&gt; with the service rules, thus achieving the deployment
of your application and the supervising at the same time.&lt;/p&gt;

&lt;h3 id=&#34;config-optional&#34;&gt;config (optional)&lt;/h3&gt;

&lt;p&gt;As you may notice the &lt;code&gt;config&lt;/code&gt; section contains mainly settings for sending
alerts/notifications apart from the &lt;code&gt;scan&lt;/code&gt; setting, therefore is totally
optional, meaning that &lt;strong&gt;Epazote&lt;/strong&gt; can still run and check your services without
the need of the &lt;code&gt;config&lt;/code&gt; section.&lt;/p&gt;

&lt;p&gt;If you want to automatically update/load services you will need the
&lt;code&gt;config - scan&lt;/code&gt; setting.&lt;/p&gt;
</description>
    </item>
    
    <item>
      <title>The services</title>
      <link>https://epazote.io/post/the-services/</link>
      <pubDate>Tue, 20 Sep 2016 01:00:00 +0000</pubDate>
      
      <guid>https://epazote.io/post/the-services/</guid>
      <description>

&lt;h1 id=&#34;the-services-section&#34;&gt;The services section&lt;/h1&gt;

&lt;p&gt;Services are the main functionality of &lt;strong&gt;Epazote&lt;/strong&gt;, is where the URL&amp;rsquo;s and the
rules based on the response are defined, since options vary from service to
service, an example could help better to understand the setup:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;services:
    my service 1:
        url: http://myservice.domain.tld/_healthcheck_
        timeout: 5
        seconds: 60
        log: http://monitor.domain.tld
        expect:
            status: 200
            header:
                content-type: application/json
            body: find this string on my site
            if_not:
                cmd: sv restart /services/my_service_1
                notify: team@domain.tld
                msg: |
                    line 1 bla bla
                    line 2
        if_status:
            500:
                cmd: reboot
            404:
                cmd: sv restart /services/cache
                msg: restarting cache
                notify: team@domain.tld x@domain.tld
        if_header:
            x-amqp-kapputt:
                cmd: restart abc
                notify: bunny@domain.tld
                msg: |
                    The rabbit is angry
                    &amp;amp; hungry
            x-db-kapputt:
                cmd: svc restart /services/db

    other service:
        url: https://self-signed.ssl.tld/ping
        header:
            Origin: http://localhost
            Accept-Encoding: gzip
        insecure: true
        ssl:
            hours: 48
        minutes: 3

    redirect service:
        url: http://test.domain.tld/
        follow: yes
        hour: 1
        threshold:
            unhealthy: 1
        expect:
            status: 302
            if_not:
                cmd: service restart abc
                notify: yes
                emoji: 1F600-1F621

    salt-master:
        test: pgrep -f salt
        if_not:
            cmd: service restart salt_master
            notify: operations@domain.tld
&lt;/code&gt;&lt;/pre&gt;

&lt;h3 id=&#34;services-name-of-service-string&#34;&gt;services - name of service (string)&lt;/h3&gt;

&lt;p&gt;An unique string that identifies your service, in the above example, there are 3
services named:
 - my service 1
 - other service
 - redirect service&lt;/p&gt;

&lt;h3 id=&#34;services-url-string&#34;&gt;services - url (string)&lt;/h3&gt;

&lt;p&gt;URL of the service to supervise&lt;/p&gt;

&lt;h3 id=&#34;services-follow-boolean-true-false&#34;&gt;services - follow (boolean true/false)&lt;/h3&gt;

&lt;p&gt;By default if a &lt;a href=&#34;https://en.wikipedia.org/wiki/HTTP_302&#34;&gt;302 Status code&lt;/a&gt; is
received, &lt;strong&gt;Epazote&lt;/strong&gt; will not follow it, if you would like to follow all
redirects, this setting must be set to &lt;strong&gt;true&lt;/strong&gt;.&lt;/p&gt;

&lt;h3 id=&#34;services-insecure-boolean-true-false&#34;&gt;services - insecure (boolean true/false)&lt;/h3&gt;

&lt;p&gt;This option explicitly allows &lt;strong&gt;Epazote&lt;/strong&gt; to perform &amp;ldquo;insecure&amp;rdquo; SSL connections.
It will disable the certificate verification.&lt;/p&gt;

&lt;h3 id=&#34;services-ssl-seconds-minutes-hours&#34;&gt;services - ssl (seconds, minutes, hours)&lt;/h3&gt;

&lt;p&gt;Alert before the certificate expires:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;ssl:
    hours: 24
&lt;/code&gt;&lt;/pre&gt;

&lt;h3 id=&#34;services-stop-int&#34;&gt;services - stop (int)&lt;/h3&gt;

&lt;p&gt;Defines the number or times the &lt;code&gt;cmd&lt;/code&gt; will be executed, by default the &lt;code&gt;cmd&lt;/code&gt;
is executed only once, with the intention to avoid indefinitely loops. If value
is set to &lt;code&gt;-1&lt;/code&gt; the &lt;code&gt;cmd&lt;/code&gt; never stops. defaults to 0, &lt;code&gt;stop 2&lt;/code&gt; will execute
&amp;ldquo;0, 1, 2&amp;rdquo; (3 times) the &lt;code&gt;cmd&lt;/code&gt;.&lt;/p&gt;

&lt;h3 id=&#34;services-timeout-in-seconds-int&#34;&gt;services - timeout in seconds (int)&lt;/h3&gt;

&lt;p&gt;Timeout specifies a time limit for the HTTP requests, A value of zero means no
timeout, defaults to 5 seconds.&lt;/p&gt;

&lt;h3 id=&#34;services-retry-limit-int&#34;&gt;services - retry_limit (int)&lt;/h3&gt;

&lt;p&gt;Specifies the number of times to retry an request, defaults to 3.&lt;/p&gt;

&lt;h3 id=&#34;services-retry-interval-int&#34;&gt;services - retry_interval (int)&lt;/h3&gt;

&lt;p&gt;Specifies the time between attempts in milliseconds. The default value is 500 (0.5 seconds).&lt;/p&gt;

&lt;h3 id=&#34;services-read-limit-int&#34;&gt;services - read_limit (int)&lt;/h3&gt;

&lt;p&gt;Read only &lt;code&gt;N&lt;/code&gt; number of bytes instead of the full
body. This helps to make a more &amp;ldquo;complete&amp;rdquo; request and
avoid getting an HTTP status code &lt;a href=&#34;http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/ts-el b-error-message.html#ts-elb-errorcodes-http408&#34;&gt;408 when testing aws ELB&lt;/a&gt;.&lt;/p&gt;

&lt;h3 id=&#34;services-threshold-healthy-unhealthy&#34;&gt;services - threshold (healthy/unhealthy)&lt;/h3&gt;

&lt;p&gt;Alert after the threshold has been reached, by default is set to 0 (disabled):&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;threshold:
    healthy: 2
    unhealth: 2
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;If set to 0 it will be disabled.&lt;/p&gt;

&lt;h3 id=&#34;services-seconds-minutes-hours&#34;&gt;services - seconds, minutes, hours&lt;/h3&gt;

&lt;p&gt;How often to check the service, the options are: (Only one should be used)&lt;/p&gt;

&lt;ul&gt;
&lt;li&gt;seconds N&lt;/li&gt;
&lt;li&gt;minutes N&lt;/li&gt;
&lt;li&gt;hours N&lt;/li&gt;
&lt;/ul&gt;

&lt;p&gt;&lt;code&gt;N&lt;/code&gt; should be an integer,  defaults to 60 seconds.&lt;/p&gt;

&lt;h3 id=&#34;services-log-url&#34;&gt;services - log (URL)&lt;/h3&gt;

&lt;p&gt;An URL to post all events, default disabled.&lt;/p&gt;

&lt;h3 id=&#34;services-expect&#34;&gt;services - expect&lt;/h3&gt;

&lt;p&gt;The &lt;code&gt;expect&lt;/code&gt; block options are:
- status (int)
- header (key, value)
- body   (regular expression)
- if_not (Action block)&lt;/p&gt;

&lt;h3 id=&#34;services-expect-status&#34;&gt;services - expect - status&lt;/h3&gt;

&lt;p&gt;An Integer representing the expected &lt;a href=&#34;https://en.wikipedia.org/wiki/List_of_HTTP_status_codes&#34;&gt;HTTP Status Code&lt;/a&gt;&lt;/p&gt;

&lt;h3 id=&#34;services-expect-header-start-with-match&#34;&gt;services - expect - header (start_with match)&lt;/h3&gt;

&lt;p&gt;A key-value map of expected headers, it can be only one or more.&lt;/p&gt;

&lt;p&gt;The headers will be considered valid if they starts with the required value,
for example if you want to check for &lt;code&gt;Content-type: application/json; charset=utf-8&lt;/code&gt;
you can simple do something like:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;header:
    Content-Type: application/json
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;This helps to simplify the matching and useful in cases where the headers
changes, for example: &lt;code&gt;Content-Range: bytes 100-64656926/64656927&lt;/code&gt; can be
matched with:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;header:
    Content-Range: bytes
&lt;/code&gt;&lt;/pre&gt;

&lt;h3 id=&#34;services-expect-body&#34;&gt;services - expect - body&lt;/h3&gt;

&lt;p&gt;A &lt;a href=&#34;https://en.wikipedia.org/wiki/Regular_expression&#34;&gt;regular expression&lt;/a&gt; used
to match a string on the body of the site, use full in cases you want to ensure
that the content delivered is always the same or keeps a pattern.&lt;/p&gt;

&lt;h3 id=&#34;services-expect-how-it-works&#34;&gt;services - expect (How it works)&lt;/h3&gt;

&lt;p&gt;The &lt;code&gt;expect&lt;/code&gt; logic tries to implement a
&lt;a href=&#34;https://en.wikipedia.org/wiki/if_else&#34;&gt;if-else&lt;/a&gt; logic &lt;code&gt;status&lt;/code&gt;, &lt;code&gt;header&lt;/code&gt;,
&lt;code&gt;body&lt;/code&gt; are the &lt;strong&gt;if&lt;/strong&gt; and the &lt;code&gt;if_not&lt;/code&gt; block becomes the &lt;strong&gt;else&lt;/strong&gt;.&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;if
    status
    header
    body
else:
    if_not
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;In must cases only one option is required, check on the above example for the service named &amp;ldquo;redirect service&amp;rdquo;.&lt;/p&gt;

&lt;p&gt;In case that more than one option is used, this is the order in how they are evaluated, no meter how they where introduced on the configuration file:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;1. body
2. status
3. header
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;The reason for this order is related to performance, at the end we want to
monitor/supervise the services in an efficient way avoiding to waste extra
resources, in must cases only the HTTP Headers are enough to take an action,
therefore we don&amp;rsquo;t need to read the full body page, because of this if no
&lt;code&gt;body&lt;/code&gt; is defined, &lt;strong&gt;Epazote&lt;/strong&gt; will only read the Headers saving with this
time and process time.&lt;/p&gt;

&lt;h3 id=&#34;services-expect-if-not&#34;&gt;services - expect - if_not&lt;/h3&gt;

&lt;p&gt;&lt;code&gt;if_not&lt;/code&gt; is a block with an action of what to do it we don&amp;rsquo;t get what we where
expecting (&lt;code&gt;expect&lt;/code&gt;). See services - Actions&lt;/p&gt;

&lt;h3 id=&#34;services-if-status-if-header&#34;&gt;services - if_status  &amp;amp; if_header&lt;/h3&gt;

&lt;p&gt;There maybe cases in where third-party dependencies are down and because of this
your application could not be working properly, for this cases the &lt;code&gt;if_status&lt;/code&gt;
and &lt;code&gt;if_header&lt;/code&gt; could be useful.&lt;/p&gt;

&lt;p&gt;For example if the database is your application could start responding an status
code 500 or either a custom header and based on does values take execute an
action:&lt;/p&gt;

&lt;p&gt;The format for &lt;code&gt;if_status&lt;/code&gt; is a key-pair where key is an int representing an
HTTP status code, and the value an Action option&lt;/p&gt;

&lt;p&gt;The format for &lt;code&gt;if_header&lt;/code&gt; is a key-pair where key is a string of something
you could relate/match and has in other if_X conditions, value is an Action.&lt;/p&gt;

&lt;p&gt;This are the only &lt;code&gt;if&#39;s&lt;/code&gt; and the order of execution:
 1. if_status
 2. if_header
 3. if_not&lt;/p&gt;

&lt;p&gt;This means that if a service uses &lt;code&gt;if_status&lt;/code&gt; and &lt;code&gt;if_not&lt;/code&gt;, it will
evaluate first the &lt;code&gt;if_status&lt;/code&gt; and execute an Action if required, in case
an &lt;code&gt;if_status&lt;/code&gt; and &lt;code&gt;if_header&lt;/code&gt; are set, same applies, first is evaluated
&lt;code&gt;if_status&lt;/code&gt;, then &lt;code&gt;if_header&lt;/code&gt; and last &lt;code&gt;if_not&lt;/code&gt;.&lt;/p&gt;

&lt;h2 id=&#34;services-actions&#34;&gt;services - Actions&lt;/h2&gt;

&lt;p&gt;An Action has five options:
 - cmd
 - notify
 - msg
 - emoji
 - http&lt;/p&gt;

&lt;p&gt;They can be used all together, only one or either none.&lt;/p&gt;

&lt;h3 id=&#34;services-actions-cmd-string&#34;&gt;services - Actions - cmd (string)&lt;/h3&gt;

&lt;p&gt;&lt;code&gt;cmd&lt;/code&gt; Contains the command to be executed.&lt;/p&gt;

&lt;h3 id=&#34;services-actions-notify-string&#34;&gt;services - Actions - notify (string)&lt;/h3&gt;

&lt;p&gt;&lt;code&gt;notify&lt;/code&gt; Should contain &lt;code&gt;yes&lt;/code&gt;, the email email address or addresses (space separated)
of the recipients that will be notified when the action is executed.&lt;/p&gt;

&lt;p&gt;If the string is &lt;code&gt;yes&lt;/code&gt; the global recipients will be used.&lt;/p&gt;

&lt;h3 id=&#34;services-actions-msg-list&#34;&gt;services - Actions - msg (list)&lt;/h3&gt;

&lt;pre&gt;&lt;code&gt;msg:
- send this if exit 0 (all OK)
- send this if exit 1 (something is wrong)
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;Based on the exit status either msg[0] or msg[1] is used,&lt;/p&gt;

&lt;h3 id=&#34;services-actions-emoji-list&#34;&gt;services - Actions - emoji (list)&lt;/h3&gt;

&lt;p&gt;&lt;code&gt;emoji&lt;/code&gt; &lt;a href=&#34;https://en.wikipedia.org/wiki/Unicode&#34;&gt;Unicode&lt;/a&gt; characters
to be used in the subject, example:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;emoji:
- 1F600
- 1F621
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;If services are OK they will use the first &lt;code&gt;1F600&lt;/code&gt; if not they will
use &lt;code&gt;1F621&lt;/code&gt;, if set to &lt;code&gt;0&lt;/code&gt; no emoji will be used. The idea behind using
&lt;a href=&#34;https://en.wikipedia.org/wiki/Emoticons_(Unicode_block)&#34;&gt;unicode/emoji&lt;/a&gt;
is to cough attention faster and not just ignore the email thinking is spam.&lt;/p&gt;

&lt;h3 id=&#34;service-actions-http-list-key-value&#34;&gt;service - Actions - http (list(key, value))&lt;/h3&gt;

&lt;p&gt;A custom URL to GET/POST depending on the exit status, example:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;http:
- url: &amp;quot;https://api.hipchat.com/v1/rooms/message?auth_token=your_token&amp;amp;room_id=7&amp;amp;from=Alerts&amp;amp;message=service+OK+_name_+_because_&amp;quot;
- url: &amp;quot;https://api.hipchat.com/&amp;quot;
    header:
    Content-Type: application/x-www-form-urlencoded
    data: |
    room_id=10&amp;amp;from=Alerts&amp;amp;message=_name_+exit+code+_exit_
    method: POST
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;When a service fails or returns an exit 1 the second url
&lt;code&gt;https://api.hipchat.com/&lt;/code&gt; with method &lt;code&gt;POST&lt;/code&gt; and the custom &lt;code&gt;data&lt;/code&gt;
will be used, notice that all the ocurances on the data that are within an
&lt;code&gt;_(key)_&lt;/code&gt; will be replaced with the corresponding value, in this case:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt; room_id=10&amp;amp;from=Alerts&amp;amp;message=_name_+exit+code+_exit_
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;will be replaced with:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt; room_id=10&amp;amp;from=Alerts&amp;amp;message=SERVICE NAME+exit+code+0
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;When recovery the first url will be used, in this case will be a GET instead of a post, so:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;https://api.hipchat.com/v1/rooms/message?auth_token=your_token&amp;amp;room_id=7&amp;amp;from=Alerts&amp;amp;message=service+OK+_name_+_because_
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;becomes:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;https://api.hipchat.com/v1/rooms/message?auth_token=your_token&amp;amp;room_id=7&amp;amp;from=Alerts&amp;amp;message=service+OK+SERVICE+NAME+STATUS+200
&lt;/code&gt;&lt;/pre&gt;

&lt;blockquote&gt;
&lt;p&gt;notice that the &lt;em&gt;name&lt;/em&gt;, &lt;em&gt;exit&lt;/em&gt;, &lt;em&gt;because&lt;/em&gt; are been replaced with the values of name, exit, because of the service.&lt;/p&gt;
&lt;/blockquote&gt;

&lt;h2 id=&#34;services-test&#34;&gt;services - Test&lt;/h2&gt;

&lt;p&gt;&lt;strong&gt;Epazote&lt;/strong&gt; It is mainly used for HTTP services, for supervising other
applications that don&amp;rsquo;t listen or accept HTTP connections, like a database,
cache engine, etc. There are tools like
&lt;a href=&#34;https://cr.yp.to/daemontools.html&#34;&gt;daemontools&lt;/a&gt;,
&lt;a href=&#34;https://immortal.run&#34;&gt;immortal&lt;/a&gt; as already mentioned, even so, &lt;strong&gt;Epazote&lt;/strong&gt;
can eventually be used to execute an action based on the exit of a command
for example:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;salt-master:
    test: pgrep -f salt
    if_not:
        cmd: service restart salt_master
        notify: operations@domain.tld
&lt;/code&gt;&lt;/pre&gt;

&lt;p&gt;In this case: &lt;code&gt;test: pgrep -f salt&lt;/code&gt; will execute the &lt;code&gt;cmd&lt;/code&gt; on the &lt;code&gt;if_not&lt;/code&gt;
block in case the exit code is &amp;gt; 0, from the &lt;code&gt;pgrep&lt;/code&gt; man page:&lt;/p&gt;

&lt;pre&gt;&lt;code&gt;EXIT STATUS
    The pgrep and pkill utilities return one of the following values upon exit:

        0       One or more processes were matched.
        1       No processes were matched.
        2       Invalid options were specified on the command line.
        3       An internal error occurred.
&lt;/code&gt;&lt;/pre&gt;

&lt;h2 id=&#34;extra-setup&#34;&gt;Extra setup&lt;/h2&gt;

&lt;p&gt;&lt;em&gt;green dots give some comfort&lt;/em&gt; &amp;ndash; Because of this when using the &lt;code&gt;log&lt;/code&gt;
option an extra service could be configure as a receiver for all the post
that &lt;strong&gt;Epazote&lt;/strong&gt; produce and based on the data obtained create a custom
dashboard, something similar to: &lt;a href=&#34;https://status.cloud.google.com/&#34;&gt;https://status.cloud.google.com/&lt;/a&gt; or
&lt;a href=&#34;http://status.aws.amazon.com/&#34;&gt;http://status.aws.amazon.com/&lt;/a&gt;&lt;/p&gt;
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