新增learn-kubernetes（https://github.com/yyong-brs/learn-kubernetes）相关文件

learn/learn-kubernetes-master/kiamol/ch09/todo-list/db/todo-db-scripts.yaml

@@ -0,0 +1,44 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: todo-db-scripts
+  labels:
+    kiamol: ch09
+data:
+  wait-service.sh: |-
+    #!/bin/sh
+    if [ "$HOSTNAME" == "$POSTGRES_PRIMARY_NAME" ]; then
+      echo '** Postgres primary **'
+    else
+      echo '** Postgres standby - waiting on DNS for primary **'
+      until nslookup ${POSTGRES_PRIMARY_FQDN}; do echo Waiting for ${POSTGRES_PRIMARY_FQDN}; sleep 1; done
+    fi
+  initialize-replication.sh: |-
+    #!/bin/bash
+    if [ "$HOSTNAME" == "$POSTGRES_PRIMARY_NAME" ]; then
+      echo '** Postgres primary - creating replication user script **'
+      cp /scripts/create-replica-user.sh /docker-entrypoint-initdb.d/create-replica-user.sh
+      ls -l /docker-entrypoint-initdb.d
+    else
+      echo '** Postgres standby - waiting on primary **'
+      until pg_isready -h "$POSTGRES_PRIMARY_FQDN"; do echo Waiting for db to be ready; sleep 1; done        
+    fi
+  create-replica-user.sh: |-
+    #!/bin/bash
+    set -e
+    psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-EOSQL
+      CREATE ROLE replication WITH REPLICATION PASSWORD '$PGPASSWORD' LOGIN
+    EOSQL
+  startup.sh: |-
+    #!/bin/sh
+    if [ "$HOSTNAME" == "$POSTGRES_PRIMARY_NAME" ]; then
+      echo '** Postgres primary **'      
+      /docker-entrypoint.sh postgres -c config_file=/conf/primary.conf -c hba_file=/conf/pg_hba.conf
+    else
+      echo '** Postgres standby - initializing replication**'
+      if [ -z "$(ls -A ${PGDATA})" ]; then
+        pg_basebackup -R -h "$POSTGRES_PRIMARY_FQDN" -D "$PGDATA" -P -U replication
+        chown -R postgres:postgres $PGDATA
+      fi
+      /docker-entrypoint.sh postgres -c config_file=/conf/standby.conf
+    fi