序

最近發現一個畫架構圖的神器diagrams，提供了很多云廠商及開源組件的圖標，相比于C4-PlantUML顯得更專業一點。
之前寫過技術文檔畫圖工具箱，diagrams屬于diagram as code工具派別。

mac安裝

brew install graphviz
pip install diagrams
brew install Python/ target=_blank class=infotextkey>[email protected]

示例

示例1

from diagrams import Diagram
from diagrams.aws.compute import EC2
from diagrams.aws.database import RDS
from diagrams.aws.NETwork import ELB

# python aws_example.py
with Diagram("Grouped Workers", show=False, direction="TB"):
    ELB("lb") >> [EC2("worker1"),
                  EC2("worker2"),
                  EC2("worker3"),
                  EC2("worker4"),
                  EC2("worker5")] >> RDS("events")

執行python example.py即可以在當前目錄生成png圖片

示例2

from diagrams import Cluster, Diagram
from diagrams.aws.compute import ECS
from diagrams.aws.database import ElastiCache, RDS
from diagrams.aws.network import ELB
from diagrams.aws.network import Route53

with Diagram("Clustered Web Services", show=False):
    DNS = Route53("dns")
    lb = ELB("lb")

    with Cluster("Services"):
        svc_group = [ECS("web1"),
                     ECS("web2"),
                     ECS("web3")]

    with Cluster("DB Cluster"):
        db_primary = RDS("userdb")
        db_primary - [RDS("userdb ro")]

    memcached = ElastiCache("memcached")

    dns >> lb >> svc_group
    svc_group >> db_primary
    svc_group >> memcached

基本語法就是import node，以with Diagram開始，之后聲明組件，然后使用with來進行分組，最后通過>>來串聯
默認文件名是Diagram名，空格替換為下劃線，可以用filename指定
圖片格式默認是png，可以用outformat=[“jpg”, “png”, “dot”]來指定要生成的圖片類型
show默認為True，也就是python生成完圖片會默認打開圖片

k8s示例

from diagrams import Cluster, Diagram
from diagrams.k8s.compute import Pod, StatefulSet
from diagrams.k8s.network import Service
from diagrams.k8s.storage import PV, PVC, StorageClass

with Diagram("Stateful Architecture", show=False):
    with Cluster("Apps"):
        svc = Service("svc")
        sts = StatefulSet("sts")

        apps = []
        for _ in range(3):
            pod = Pod("pod")
            pvc = PVC("pvc")
            pod - sts - pvc
            apps.append(svc >> pod >> pvc)

    apps << PV("pv") << StorageClass("sc")

開源組件示例

from diagrams import Cluster, Diagram
from diagrams.onprem.analytics import Spark
from diagrams.onprem.compute import Server
from diagrams.onprem.database import PostgreSQL
from diagrams.onprem.inmemory import redis
from diagrams.onprem.aggregator import Fluentd
from diagrams.onprem.monitoring import Grafana, Prometheus
from diagrams.onprem.network import Nginx
from diagrams.onprem.queue import Kafka

with Diagram("Advanced Web Service with On-Premise", show=False):
    ingress = Nginx("ingress")

    metrics = Prometheus("metric")
    metrics << Grafana("monitoring")

    with Cluster("Service Cluster"):
        grpcsvc = [
            Server("grpc1"),
            Server("grpc2"),
            Server("grpc3")]

    with Cluster("Sessions HA"):
        primary = Redis("session")
        primary - Redis("replica") << metrics
        grpcsvc >> primary

    with Cluster("Database HA"):
        primary = PostgreSQL("users")
        primary - PostgreSQL("replica") << metrics
        grpcsvc >> primary

    aggregator = Fluentd("logging")
    aggregator >> Kafka("stream") >> Spark("analytics")

    ingress >> grpcsvc >> aggregator

主要結構

node

# aws resources
from diagrams.aws.compute import ECS, Lambda
from diagrams.aws.database import RDS, ElastiCache
from diagrams.aws.network import ELB, Route53, VPC
...

# azure resources
from diagrams.azure.compute import FunctionApps
from diagrams.azure.storage import BlobStorage
...

# alibaba cloud resources
from diagrams.alibabacloud.compute import ECS
from diagrams.alibabacloud.storage import ObjectTableStore
...

# gcp resources
from diagrams.gcp.compute import AppEngine, GKE
from diagrams.gcp.ml import AutoML 
...

# k8s resources
from diagrams.k8s.compute import Pod, StatefulSet
from diagrams.k8s.network import Service
from diagrams.k8s.storage import PV, PVC, StorageClass
...

# oracle resources
from diagrams.oci.compute import VirtualMachine, ContAIner
from diagrams.oci.network import Firewall
from diagrams.oci.storage import FileStorage, StorageGateway

完整版見nodes

數據流及布局

• >>表示從左到右連接
• <<表示從右到左連接
• -表示無方向的連接

Diagram有個屬性direction來表示整體布局，可選的值有TB, BT, LR及RL，默認是LR，即從左到右

TB: top to bottom
BT: bottom to top
LR: left to right
RL: right to left

Cluster用于分組，也支持內嵌，比如

 with Cluster("Event Flows"):
        with Cluster("Event Workers"):
            workers = [ECS("worker1"),
                       ECS("worker2"),
                       ECS("worker3")]

        queue = SQS("event queue")

        with Cluster("Processing"):
            handlers = [Lambda("proc1"),
                        Lambda("proc2"),
                        Lambda("proc3")]

連接符之間可以用Edge來銜接，用于個性化處理邊的屬性，比如

metrics = Prometheus("metric")
    metrics << Edge(color="firebrick", style="dashed") << Grafana("monitoring")

小結

diagrams是基于python的一款diagram as code工具，它最大的特點就是提供了很多云廠商及開源組件的圖標，畫出來的圖顯得更專業一點，也更易懂一點。

doc

• diagrams
• Diagrams: Diagram as Code
• diagrams examples
• 技術文檔畫圖工具箱