### Start PostgreSQL Service

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/how-to/PostgreSQL-setup.md

Ensures the PostgreSQL service is running after installation.

```bash
sudo systemctl start postgresql
```

--------------------------------

### Example: Get Subscribers for a Visualization

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/metadata.md

Example of retrieving subscribers for a specific visualization object using its UID.

```http
/api/visualizations/DkPKc1EUmC2/subscribers
```

--------------------------------

### Enable and Start Prometheus Service

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/reference/monitoring.md

Enable the Prometheus service to start on boot and then start it immediately. Verify its status to ensure it's running.

```bash
systemctl enable prometheus
systemctl start prometheus
```

--------------------------------

### Install Nginx

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/reference/reverse_proxy_nginx.md

Installs the Nginx web server using apt-get. This is a prerequisite for setting up Nginx as a reverse proxy.

```bash
sudo apt-get install -y nginx
```

--------------------------------

### Install Nginx

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/reference/monitoring.md

Install the Nginx web server if it is not already present on the system.

```bash
apt update
apt-get install nginx
```

--------------------------------

### Ansible Playbook for PostgreSQL Installation

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/how-to/PostgreSQL-setup.md

Automates the setup of PostgreSQL on a Debian-based system. It updates the system, adds the PostgreSQL repository, installs the specified version along with PostGIS, and ensures the service is running.

```yaml
- hosts: 127.0.0.1
  become: true
  gather_facts: true
  vars:
    postgresql_version: 16
  tasks:
    - name: "Update and upgrade database"
      ansible.builtin.apt:
        upgrade: true
        update_cache: true
        cache_valid_time: 86400

    # Adding postgresql signing key
    - name: "Adding postgresql repo signing key"
      ansible.builtin.get_url:
        url: "https://www.postgresql.org/media/keys/ACCC4CF8.asc"
        dest: /etc/apt/trusted.gpg.d/postgresql.asc
        owner: root
        group: root
        mode: '0600'

    # adding apt signing key
    - name: "Adding postgres apt repository to sources list"
      ansible.builtin.apt_repository:
        repo: "deb [arch={{ guest_os_arch|default('amd64') }} signed-by=/etc/apt/trusted.gpg.d/postgresql.asc] https://apt.postgresql.org/pub/repos/apt {{ hostvars[inventory_hostname]['ansible_facts']['distribution_release'] }}-pgdg main"
        update_cache: true
        filename: apt_postgresql_org
        state: present

    # Install postgresql and python module for Postgres
    - name: "Installing postgres version {{ postgresql_version }}"
      ansible.builtin.apt:
        name:
          - ca-certificates
          - postgresql-{{ postgresql_version }}
          - postgresql-client-{{ postgresql_version }}
          - postgresql-{{ postgresql_version }}-postgis-{{ '2.5' if guest_os == '20.04' else '3' }}
          - python3-psycopg2
          - libdbd-pg-perl
    
    # sometimes postgres is installed but not started
    - name: "Ensure postgresql is running"
      become: true
      ansible.builtin.service:
        name: postgresql
        state: started
        enabled: true

```

--------------------------------

### Get Database Locales

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/i18n.md

Example request to get database locales for a specific country and language. Uses GET request.

```bash
/api/locales/dbLocales?country=US&language=en
```

--------------------------------

### Job Queue Details Example

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example JSON response showing the details of a job queue named 'myQ'.

```json
{
  "name": "myQ",
  "cronExpression": "0 0 1 ? * *",
  "sequence": ["FgAxa6eRSzQ", "BeclVERfWbg" ]
}
```

--------------------------------

### Get Details of a Specific Running Job (Example)

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example of retrieving the status of a running ANALYTICS_TABLE job.

```bash
GET /api/scheduling/running/ANALYTICS_TABLE
```

--------------------------------

### Analytics Explain Endpoint Example

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/analytics.md

This example shows a GET request to the analytics explain endpoint. It includes various parameters to specify dimensions, filters, and metadata details for analyzing query performance.

```http
GET /api/analytics/explain?displayProperty=NAME
  &dimension=dx:Uvn6LCg7dVU;sB79w2hiLp8,ou:USER_ORGUNIT
  &filter=pe:THIS_YEAR&includeNumDen=false&skipMeta=false
  &skipData=true&includeMetadataDetails=true
```

--------------------------------

### Get Details of a Specific Completed Job (Example)

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example of retrieving details for a completed ANALYTICS_TABLE job.

```bash
GET /api/scheduling/completed/ANALYTICS_TABLE
```

--------------------------------

### Start and Enable PostgreSQL Service

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-manual-install.md

Ensures the PostgreSQL service is running and configured to start automatically on system boot.

```sh
sudo systemctl start postgresql
sudo systemctl enable postgresql
```

--------------------------------

### List of Job Queue Names Example

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example JSON response showing a list of job queue names.

```json
["queue_a", "queue_b"]
```

--------------------------------

### Enable and Start Redis Service

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/how-to/installing_redis.md

Ensure the Redis server service is enabled to start automatically on boot and start the service immediately.

```bash
sudo systemctl enable redis-server
sudo systemctl start redis-server
```

--------------------------------

### Start DHIS2 Instance

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-manual-install.md

Starts the DHIS2 instance by executing the Tomcat startup script as the 'dhis' user.

```bash
sudo -u dhis /home/dhis/tomcat-dhis/bin/startup.sh
```

--------------------------------

### Install Perl

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/tutorials/analysing-postgresql-logs-using-pgbadger.md

Ensure Perl is installed on your system, as it is a prerequisite for pgBadger.

```bash
sudo apt install perl
```

--------------------------------

### Install pgBadger

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/tutorials/analysing-postgresql-logs-using-pgbadger.md

Download, extract, and install the pgBadger tool. Adjust the version number in the commands to match the downloaded release.

```bash
tar xvf pgbadger-13.1.tar.gz
cd pgbadger-13.1
perl Makefile.PL
make && sudo make install
```

--------------------------------

### Example User Lookup Query

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/users.md

An example request to the user lookup endpoint with a query string to find users.

```HTTP
/api/userLookup?query=John
```

--------------------------------

### Install GoAccess on Ubuntu

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/tutorials/analysing-nginx-logs-using-goaccess.md

Installs the latest GoAccess version by adding its official repository and using apt-get. Ensure you have wget and gpg installed.

```bash
wget -O - https://deb.goaccess.io/gnugpg.key | gpg --dearmor | sudo tee /usr/share/keyrings/goaccess.gpg >/dev/null
echo "deb [signed-by=/usr/share/keyrings/goaccess.gpg] https://deb.goaccess.io/ $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/goaccess.list
sudo apt-get update
sudo apt-get install goaccess
```

--------------------------------

### Example User Retrieval by Identifier

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/users.md

An example of how to request a user's full details using their specific identifier.

```HTTP
/api/users/OYLGMiazHtW
```

--------------------------------

### Example JSON response for enrollments

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/tracker.md

This is an example of the JSON structure returned when querying the enrollments endpoint.

```JSON
{
  "pager": {
    "page": 1,
    "pageSize": 1
  },
  "enrollments": [
    {
      "enrollment": "TRE0GT7eh7Q",
      "createdAt": "2019-08-21T13:28:00.056",
      "createdAtClient": "2018-11-13T15:06:49.009",
      "updatedAt": "2019-08-21T13:29:44.942",
      "updatedAtClient": "2019-08-21T13:29:44.942",
      "trackedEntity": "s4NfKOuayqG",
      "program": "M3xtLkYBlKI",
      "status": "COMPLETED",
      "orgUnit": "DiszpKrYNg8",
      "enrolledAt": "2023-11-13T00:00:00.000",
      "occurredAt": "2023-11-13T00:00:00.000",
      "followUp": false,
      "deleted": false,
      "notes": []
    }
  ]
}
```

--------------------------------

### Get Organisation Unit Profile Data Example Request

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/organisation-unit-profile.md

Example of a GET request to retrieve profile data for a specific organisation unit and period. The 'period' parameter is optional.

```http
GET /api/organisationUnitProfile/DiszpKrYNg8/data?period=2021
```

--------------------------------

### Install an App

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/apps.md

Install a DHIS2 app by uploading a zip file using a POST request. Ensure the 'file' part is correctly formatted.

```bash
curl -X POST -u user:pass -F file=@app.zip "http://server.com/api/33/apps"
```

--------------------------------

### Tracked Entity Single Object Example Request

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/tracker.md

This is an example GET request to retrieve a specific tracked entity using its UID.

```http
GET /api/tracker/trackedEntities/PQfMcpmXeFE
```

--------------------------------

### Install Glowroot and Set Permissions

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/tutorials/glowroot.md

Steps to download, unpack, and set ownership for Glowroot. Ensure the DHIS2 service user has write access to the installation directory.

```bash
mkdir -p /opt/glowroot
cd /opt/glowroot
wget https://github.com/glowroot/glowroot/releases/download/v0.13.6/glowroot-0.13.6-dist.zip
unzip glowroot-0.13.6-dist.zip
chown -R dhis: /opt/glowroot
```

--------------------------------

### Request Example for Tracker Job Status

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/tracker.md

An example of a GET request to retrieve the status of a tracker import job using its UID.

```http
GET /tracker/jobs/PQK63sMwjQp
```

--------------------------------

### Run DHIS2 Installation Script

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-automated-install.md

Navigate to the deploy directory, copy the host template, and execute the main deployment script to install DHIS2 and its components.

```bash
cd dhis2-server-tools/deploy
cp inventory/hosts.template inventory/hosts
sudo ./deploy.sh
```

--------------------------------

### Install Redis Server

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/how-to/installing_redis.md

Install the Redis server package using APT after updating your package list and adding the necessary repository.

```bash
sudo apt install redis-server
```

--------------------------------

### Request Example for Tracker Import Report

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/tracker.md

An example of a GET request to retrieve the report for a tracker import job, specifying the job UID and report mode.

```http
GET /tracker/jobs/mEfEaFSCKCC/report
```

--------------------------------

### Example Event Aggregate Query with Filters

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/analytics.md

An example query to get aggregate event counts for a program, filtering by specific data elements ('Gender', 'Age') and date range.

```HTTP
/api/analytics/events/aggregate/eBAyeGv0exc?startDate=2016-01-01&endDate=2016-10-31
&dimension=ou:O6uvpzGd5pu&dimension=oZg33kd9taw:EQ:Female&dimension=qrur9Dvnyt5:GT:50
```

--------------------------------

### Request to Get a Single Event by UID

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/tracker.md

This is an example of a GET request to retrieve a single event using its unique identifier (UID). The `fields` parameter can be used to specify which sub-objects to include in the response.

```http
GET /api/tracker/events/rgWr86qs0sI
```

--------------------------------

### Get All System Settings

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/settings-and-configuration.md

Retrieves all available system settings.

```APIDOC
## GET /api/33/systemSettings

### Description
Retrieves all system settings.

### Method
GET

### Endpoint
/api/33/systemSettings

### Response
#### Success Response (200)
- **(application/json)** - A JSON object containing all system settings as key-value pairs.

#### Response Example
```json
{
  "keyUiLocale": "en",
  "applicationTitle": "DHIS2",
  ...
}
```
```

--------------------------------

### GET /api/apps - List Installed Apps

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/apps.md

Retrieves a list of all installed DHIS2 apps. The response includes an 'key' property for each app. This endpoint can be filtered by app type and name using query parameters.

```APIDOC
## GET /api/apps

### Description
Lists all installed DHIS2 applications. The response contains a 'key' property for each app. Filtering by app type and name is supported.

### Method
GET

### Endpoint
`/api/{version}/apps`

### Query Parameters
- **filter** (string) - Optional - Allows filtering the list of apps. Supported formats include `appType:eq:DASHBOARD_APP` and `name:ilike:youtube`.
  - `appType` supports `eq` operator.
  - `name` supports `eq` and `ilike` operators.

### Request Example
```bash
curl -u user:pass -H "Accept: application/json" "http://server.com/api/33/apps"
```

### Response
#### Success Response (200)
- **apps** (array) - A list of installed app objects, each containing a 'key' property.

#### Response Example
```json
[
  {
    "key": "my-app-key",
    "name": "My App",
    "description": "An example app."
  }
]
```
```

--------------------------------

### POST /api/apps - Install an App

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/apps.md

Installs a new app by uploading a ZIP archive. The request must be a POST request with the file part containing the app's ZIP file.

```APIDOC
## POST /api/apps

### Description
Installs a DHIS2 application by uploading a ZIP archive.

### Method
POST

### Endpoint
`/api/{version}/apps`

### Request Body
- **file** (file) - Required - The ZIP archive of the app to be installed.

### Request Example
```bash
curl -X POST -u user:pass -F file=@app.zip "http://server.com/api/33/apps"
```
```

--------------------------------

### Get id and name from data elements and associated data sets

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/metadata.md

To retrieve fields from nested objects, use bracket notation. This example gets the `id` and `name` from data elements and their associated data sets.

```HTTP
/api/dataElements?fields=id,name,dataSets[id,name]
```

--------------------------------

### Example Enrollment Query with Program Indicator and Relationship

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/analytics.md

Example of a query to retrieve enrollments for a specific program and date range, displaying counts of linked entities via a specified relationship type and program indicator.

```HTTP
/api/analytics/enrollments/query/WSGAb5XwJ3Y.json?dimension=mxZDvSZYxlw.nFICjJluo74
&startDate=2019-01-01&endDate=2019-01-31
```

--------------------------------

### Create DHIS2 Instance Configuration File

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-automated-install.md

Create a configuration file for a DHIS2 instance by copying the template provided in `dhis2-server-tools/deploy/inventory/host_vars/`. This allows for instance-specific variable definitions.

```bash
cp dhis2-server-tools/deploy/inventory/host_vars/dhis.template dhis2-server-tools/deploy/inventory/host_vars/dhis
```

--------------------------------

### GET /api/dataItems - Pagination

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/visualizations.md

Details on how pagination is handled for the /api/dataItems endpoint, including how to disable it and an example of a paginated response.

```APIDOC
## GET /api/dataItems - Pagination

### Description
Pagination is enabled by default for the `/api/dataItems` endpoint. You can disable it by setting the `paging` query parameter to `false`.

### Method
GET

### Endpoint
/api/dataItems

### Parameters
#### Query Parameters
- **paging** (boolean) - Optional - Set to `false` to disable pagination. Defaults to `true`.

### Request Example (Disabling Pagination)
```
GET /api/dataItems?filter=dimensionItemType:in:[INDICATOR]&paging=false
```

### Response Example (Paginated Response)
```json
{
  "pager": {
    "page": 1,
    "pageCount": 20,
    "total": 969,
    "pageSize": 50
  },
  "dataItems": [...] 
}
```

### Notes
- For elements associated with a Program, the program name is prefixed to the element name, except for `Program Indicators`.
- The endpoint returns only aggregatable data items. Valid aggregatable types include: `TEXT, LONG_TEXT, LETTER, BOOLEAN, TRUE_ONLY, NUMBER, UNIT_INTERVAL, PERCENTAGE, INTEGER, INTEGER_POSITIVE, INTEGER_NEGATIVE, INTEGER_ZERO_OR_POSITIVE, COORDINATE`.
- Filtering is supported for the following attributes: `displayName`, `name`, `valueType`, `id`, `dimensionItemType`, `programId`.
- Ordering might be considered invalid if conflicting filters are applied (e.g., ordering by `name` while filtering by `displayName`).
```

--------------------------------

### Manage Nginx Service

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/reference/reverse_proxy_nginx.md

Commands to start, reload, and stop the Nginx service. Use these to manage the Nginx process after installation or configuration changes.

```bash
sudo /etc/init.d/nginx start
```

```bash
sudo /etc/init.d/nginx reload
```

```bash
sudo /etc/init.d/nginx stop
```

--------------------------------

### Example Wildcard Route Usage

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/route.md

Demonstrates how to run a wildcard route with sub-paths. The specified sub-paths are appended to the base wildcard URL for the upstream request.

```bash
GET /api/routes/{id}/run/get
GET /api/routes/postman-wildcard/run/get
POST /api/routes/{id}/run/post
POST /api/routes/postman-wildcard/run/post
```

--------------------------------

### Search for Job Execution Errors Including Input

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example of a GET request to search for job execution errors, including the input payload of the job run.

```http
GET /api/jobConfigurations/errors?includeInput=true
```

--------------------------------

### Retrieve List of Configured Gateways

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/sms.md

Use this GET endpoint to retrieve a list of all configured SMS gateways. No specific setup is required beyond having gateways configured.

```bash
GET /api/33/gateways
```

--------------------------------

### Basic Enrollment Query Example

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/analytics.md

Retrieve enrollments from a specific program with dimensions and filters for data elements and attributes. Filters can include operators like 'eq' for equality.

```HTTP
/api/analytics/enrollments/query/WSGAb5XwJ3Y.json
  ?dimension=ou:ImspTQPwCqd
  &dimension=w75KJ2mc4zz
  &dimension=WZbXY0S00lP.de0FEHSIoxh:eq:1
  &dimension=w75KJ2mc4zz
  &dimension=WZbXY0S00lP.sWoqcoByYmD
  &dimension=edqlbukwRfQ.vANAXwtLwcT
  &startDate=2019-01-01&endDate=2019-01-31
```

--------------------------------

### Check User Authority

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/overview.md

Check whether the currently authenticated user has a specific authority by making a GET request to the /api/me/authorization/{authority} endpoint. For example, to check for 'F_CONSTANT_ADD'.

```HTTP
GET /api/me/authorization/F_CONSTANT_ADD
```

--------------------------------

### Search for Job Execution Errors with Specific Criteria

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/scheduling.md

Example of a GET request to search for job execution errors, filtering by job type, error code, and date range.

```http
GET /api/jobConfigurations/errors?type=TRACKER_IMPORT_JOB&code=E1002&from=2024-01-01&to=2024-01-02
```

--------------------------------

### SQL View API Request with Filtering (Not Like Operator)

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/visualizations.md

Example of excluding organization units whose names start with 'Bo' using the '!like' operator in SQL view filtering.

```http
/api/sqlViews/w3UxFykyHFy/data.json?filter=orgunit_name:!like:Bo
```

--------------------------------

### Create SQL Views

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/maintenance.md

Recreates all SQL views in the database. Use POST or PUT method.

```bash
POST PUT /api/maintenance/sqlViewsCreate
```

--------------------------------

### Example of using 'size' and 'rename' transformers

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/metadata-gist.md

Demonstrates how to use the 'size' transformer to get the count of children and 'rename' to change the field name. This is useful for optimizing responses by only fetching necessary data.

```api
/api/organisationUnits/gist?fields=*,children::size~rename(child-count)
```

--------------------------------

### List Ansible Connection Plugins

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/dhis2-tools.md

Use this command to list all available Ansible connection plugins. This is useful for understanding the different ways Ansible can connect to target hosts.

```bash
ansible-doc -t connection --list
```

--------------------------------

### Example: Check if orgunit code starts with WB_

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/user/configure-programs-in-the-maintenance-app.md

Uses the `d2:left` function to extract the first three characters of the `orgunit_code` and compares them to a prefix. This is useful for filtering based on organizational unit hierarchy or naming conventions.

```text
d2:left(V{orgunit_code},3) == 'WB_'
```

--------------------------------

### Install Recommended JRE

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-manual-install.md

Installs the recommended Java Runtime Environment (JRE) for a specific DHIS2 version. Replace <jre_version> with the appropriate version number from the documentation table.

```sh
sudo apt-get install -y openjdk-<jre_version>-jre-headless
```

--------------------------------

### Verify Java Installation

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/sysadmin/getting-started/linux-manual-install.md

Checks the installed Java version to confirm the installation was successful.

```sh
java -version
```

--------------------------------

### Retrieve Multiple Data Values with Date Range and Children - cURL

Source: https://github.com/dhis2/dhis2-docs/blob/master/src/developer/web-api/data.md

This cURL example demonstrates fetching a larger bulk of data values using start and end dates, multiple data sets, multiple organisation units, and including child organisation units. The 'period' parameter takes precedence over 'startDate' and 'endDate' if both are provided.

```bash
curl "https://play.dhis2.org/demo/api/dataValueSets?dataSet=pBOMPrpg1QX&dataSet=BfMAe6Itzgt
  &startDate=2013-01-01&endDate=2013-01-31&orgUnit=YuQRtpLP10I&orgUnit=vWbkYPRmKyS&children=true"
  -H "Accept:application/xml" -u admin:district
```