如果文章中存在某些名词不理解，不用太在意，可先放过，先部署好 环境体验一下airflow功能，在后续学习中再深入理解。
更多airflow资料，可查看：airflow从入门到精通学习笔记系列
如安装过程中遇到问题，可查看 airflow安装及使用的常见问题
安装
实验环境：
centos7
python3.6
安装脚本：
yum install -y python36
yum install -y python36-pip
yum install -y python36-devel
pip3 install apache-airflow
pip3 install pymysql
设置airflow的根目录：
echo "export AIRFLOW_HOME=/data/airflow" >> /root/.bashrc
source /root/.bashrc
初始化
初始化数据库表（默认使用本地的sqlite数据库）：
[root@VM_7_246_centos /data]# airflow initdb
[2019-08-05 19:23:29,691] {__init__.py:51} INFO - Using executor SequentialExecutor
DB: sqlite:////data/airflow/airflow.db
[2019-08-05 19:23:30,019] {db.py:350} INFO - Creating tables
INFO [alembic.runtime.migration] Context impl SQLiteImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Running upgrade -> e3a246e0dc1, current schema
INFO [alembic.runtime.migration] Running upgrade e3a246e0dc1 -> 1507a7289a2f, create is_encrypted
/usr/local/lib/python3.6/site-packages/alembic/util/messaging.py:69: UserWarning: Skipping unsupported ALTER for creation of implicit constraint
warnings.warn(msg)
INFO [alembic.runtime.migration] Running upgrade 1507a7289a2f -> 13eb55f81627, maintain history for compatibility with earlier migrations
INFO [alembic.runtime.migration] Running upgrade 13eb55f81627 -> 338e90f54d61, More logging into task_instance
INFO [alembic.runtime.migration] Running upgrade 338e90f54d61 -> 52d714495f0, job_id indices
INFO [alembic.runtime.migration] Running upgrade 52d714495f0 -> 502898887f84, Adding extra to Log
INFO [alembic.runtime.migration] Running upgrade 502898887f84 -> 1b38cef5b76e, add dagrun
INFO [alembic.runtime.migration] Running upgrade 1b38cef5b76e -> 2e541a1dcfed, task_duration
INFO [alembic.runtime.migration] Running upgrade 2e541a1dcfed -> 40e67319e3a9, dagrun_config
INFO [alembic.runtime.migration] Running upgrade 40e67319e3a9 -> 561833c1c74b, add password column to user
INFO [alembic.runtime.migration] Running upgrade 561833c1c74b -> 4446e08588, dagrun start end
INFO [alembic.runtime.migration] Running upgrade 4446e08588 -> bbc73705a13e, Add notification_sent column to sla_miss
INFO [alembic.runtime.migration] Running upgrade bbc73705a13e -> bba5a7cfc896, Add a column to track the encryption state of the 'Extra' field in connection
INFO [alembic.runtime.migration] Running upgrade bba5a7cfc896 -> 1968acfc09e3, add is_encrypted column to variable table
INFO [alembic.runtime.migration] Running upgrade 1968acfc09e3 -> 2e82aab8ef20, rename user table
INFO [alembic.runtime.migration] Running upgrade 2e82aab8ef20 -> 211e584da130, add TI state index
INFO [alembic.runtime.migration] Running upgrade 211e584da130 -> 64de9cddf6c9, add task fails journal table
INFO [alembic.runtime.migration] Running upgrade 64de9cddf6c9 -> f2ca10b85618, add dag_stats table
INFO [alembic.runtime.migration] Running upgrade f2ca10b85618 -> 4addfa1236f1, Add fractional seconds to mysql tables
INFO [alembic.runtime.migration] Running upgrade 4addfa1236f1 -> 8504051e801b, xcom dag task indices
INFO [alembic.runtime.migration] Running upgrade 8504051e801b -> 5e7d17757c7a, add pid field to TaskInstance
INFO [alembic.runtime.migration] Running upgrade 5e7d17757c7a -> 127d2bf2dfa7, Add dag_id/state index on dag_run table
INFO [alembic.runtime.migration] Running upgrade 127d2bf2dfa7 -> cc1e65623dc7, add max tries column to task instance
INFO [alembic.runtime.migration] Running upgrade cc1e65623dc7 -> bdaa763e6c56, Make xcom value column a large binary
INFO [alembic.runtime.migration] Running upgrade bdaa763e6c56 -> 947454bf1dff, add ti job_id index
INFO [alembic.runtime.migration] Running upgrade 947454bf1dff -> d2ae31099d61, Increase text size for MySQL (not relevant for other DBs' text types)
INFO [alembic.runtime.migration] Running upgrade d2ae31099d61 -> 0e2a74e0fc9f, Add time zone awareness
INFO [alembic.runtime.migration] Running upgrade d2ae31099d61 -> 33ae817a1ff4, kubernetes_resource_checkpointing
INFO [alembic.runtime.migration] Running upgrade 33ae817a1ff4 -> 27c6a30d7c24, kubernetes_resource_checkpointing
INFO [alembic.runtime.migration] Running upgrade 27c6a30d7c24 -> 86770d1215c0, add kubernetes scheduler uniqueness
INFO [alembic.runtime.migration] Running upgrade 86770d1215c0, 0e2a74e0fc9f -> 05f30312d566, merge heads
INFO [alembic.runtime.migration] Running upgrade 05f30312d566 -> f23433877c24, fix mysql not null constraint
INFO [alembic.runtime.migration] Running upgrade f23433877c24 -> 856955da8476, fix sqlite foreign key
INFO [alembic.runtime.migration] Running upgrade 856955da8476 -> 9635ae0956e7, index-faskfail
INFO [alembic.runtime.migration] Running upgrade 9635ae0956e7 -> dd25f486b8ea
INFO [alembic.runtime.migration] Running upgrade dd25f486b8ea -> bf00311e1990, add index to taskinstance
INFO [alembic.runtime.migration] Running upgrade 9635ae0956e7 -> 0a2a5b66e19d, add task_reschedule table
INFO [alembic.runtime.migration] Running upgrade 0a2a5b66e19d, bf00311e1990 -> 03bc53e68815, merge_heads_2
INFO [alembic.runtime.migration] Running upgrade 03bc53e68815 -> 41f5f12752f8, add superuser field
INFO [alembic.runtime.migration] Running upgrade 41f5f12752f8 -> c8ffec048a3b, add fields to dag
INFO [alembic.runtime.migration] Running upgrade c8ffec048a3b -> a56c9515abdc, Remove dag_stat table
INFO [alembic.runtime.migration] Running upgrade c8ffec048a3b -> dd4ecb8fbee3, Add schedule interval to dag
INFO [alembic.runtime.migration] Running upgrade dd4ecb8fbee3 -> 939bb1e647c8, task reschedule fk on cascade delete
WARNI [airflow.utils.log.logging_mixin.LoggingMixin] cryptography not found - values will not be stored encrypted.
Done.
查看其生成文件：
[root@VM_7_246_centos /data]# ls $AIRFLOW_HOME
airflow.cfg airflow.db logs unittests.cfg
配置
配置MySQL数据库（创建airflow数据库，并创建用户和授权，给airflow访问数据库使用）：
# 新建airflow的数据库
MariaDB [(none)]> CREATE DATABASE airflow;
# 授权从localhost登录的root账号对airflow的所有操作
MariaDB [(none)]> GRANT all privileges on root.* TO 'root'@'localhost' IDENTIFIED BY '123456';
MariaDB [(none)]> FLUSH PRIVILEGES;
配置airflow使用LocalExecutor执行器，及使用MySQL数据库：
vim airflow/airflow.cfg
# The executor class that airflow should use. Choices include
# SequentialExecutor, LocalExecutor, CeleryExecutor, DaskExecutor, KubernetesExecutor
#executor = SequentialExecutor
executor = LocalExecutor
# The SqlAlchemy connection string to the metadata database.
# SqlAlchemy supports many different database engine, more information
# their website
#sql_alchemy_conn = sqlite:////data/airflow/airflow.db
sql_alchemy_conn = mysql+pymysql://root:123456@localhost:3306/airflow
再次初始化数据库表（在MySQL中创建）：
airflow initdb
查看创建的airflow数据表：
MariaDB [None] > use airflow;
MariaDB [airflow]> show tables;
+-------------------+
| Tables_in_airflow |
+-------------------+
| alembic_version |
| chart |
| connection |
| dag |
| dag_pickle |
| dag_run |
| dag_stats |
| import_error |
| job |
| known_event |
| known_event_type |
| log |
| sla_miss |
| slot_pool |
| task_fail |
| task_instance |
| users |
| variable |
| xcom |
+-------------------+
服务启动
添加airflow-scheduler服务启动脚本：
/usr/lib/systemd/system/airflow-scheduler.service
[Unit]
Description=Airflow Scheduler
Wants=network-online.target
After=network-online.target
[Service]
User=root
Group=root
Type=simple
Restart=on-failure
Environment=export AIRFLOW_HOME=/data/airflow
ExecStart=/usr/local/bin/airflow scheduler
LimitNOFILE=10000
TimeoutStopSec=20
[Install]
WantedBy=multi-user.target
启动airflow-scheduler服务：
systemctl start airflow-scheduler
添加airflow-webserver服务启动脚本：
/usr/lib/systemd/system/airflow-webserver.service
[Unit]
Description=Airflow Scheduler
Wants=network-online.target
After=network-online.target
[Service]
User=root
Group=root
Type=simple
Restart=on-failure
Environment=export AIRFLOW_HOME=/data/airflow
ExecStart=/usr/local/bin/airflow webserver
LimitNOFILE=10000
TimeoutStopSec=20
[Install]
WantedBy=multi-user.target
启动airflow-webserver服务：
systemctl start airflow-webserver
使用
访问http://localhost:8080地址，看到首页界面即成功；
首页
更多airflow资料，可查看：airflow从入门到精通学习笔记系列
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