Configuration Resource, 4, 17, 147, 149,
151-156, 163, 165
Configuration Template, 165
EnvVar Configuration, 147, 149
Immutable Configuration, 163
Predictable Demands, 17
Configuration Template, 149, 165-171
EnvVar Configuration, 149
Container Linux Update Operator, 179
container orchestration platforms, xi, 3
containers
basics of, 4
enhancing through collaboration, 131
observability options, 39
resource demands, 49
runtime dependencies, 16
separating initialization from main duties,
125
upgrade and rollback of container groups,
25
volumes, 159
Continuous Delivery (CD), 221
Continuous Integration (CI), 221
Controller, 97, 175-187, 189, 192, 194
Operator, 189, 192, 194
Stateful Service, 97
convention over configuration paradigm, 148
CoreOS, 195
CPU and memory demands, 22
CRDs (see custom resource definitions)
CronJob implementation, 70
custom resource definitions (CRDs)
application CRDs, 193
installation CRDs, 192
managing domain concepts with, 190
operator development and deployment, 195
subresources, 191
support for, 194
uses for, 189
custom scheduling approach, 58
D
Daemon Service, 4, 63, 73-77
Batch Job, 63
daemonless builds, 222
DaemonSet, 63
data stores, decoupling access to external, 140
Declarative Deployment, 24, 25-33
Predictable Demands, 24
declarative resource-centric APIs, 175
declarative scaling, 204
default scheduling alteration, 58
default values, 148
dependencies, 16, 139
Deployment
blue-green, 30
fixed, 29
parallel, 95
resource, 25
rolling, 27
design patterns
concept of, xii
design patterns, xiii
pattern language, xii
discovery (see also Service Discovery)
service discovery in Kubernetes, 113
through DNS lookup, 103
through environment variables, 102
DNS lookup, 103
Docker builds, 227
Docker volumes, 158
Domain-Driven Design, 2
Downward API, 118
DRY configurations, 170
E
Elastic Scale, 79, 191, 203-220, 230
Image Builder, 230
Operator, 191
Singleton Service, 79
emptyDir volume type, 16
endpoints, discovering, 99
environment variables
versus ConfigMaps, 151
service discovery through, 102
storing application configuration in, 145
EnvVar Configuration, 145-149, 151, 157
Configuration Resource, 151
Immutable Configuration, 157
Etcd operator, 200
event-driven
application interactions, 69
architecture, 176
F
fabric8/configmapcontroller, 179
failures
detecting, 35
240 | Index